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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * intel_pt_decoder.c: Intel Processor Trace support
   4 * Copyright (c) 2013-2014, Intel Corporation.
   5 */
   6
   7#ifndef _GNU_SOURCE
   8#define _GNU_SOURCE
   9#endif
  10#include <stdlib.h>
  11#include <stdbool.h>
  12#include <string.h>
  13#include <errno.h>
  14#include <stdint.h>
  15#include <inttypes.h>
  16#include <linux/compiler.h>
  17#include <linux/string.h>
  18#include <linux/zalloc.h>
  19
  20#include "../auxtrace.h"
  21
  22#include "intel-pt-insn-decoder.h"
  23#include "intel-pt-pkt-decoder.h"
  24#include "intel-pt-decoder.h"
  25#include "intel-pt-log.h"
  26
  27#define BITULL(x) (1ULL << (x))
  28
  29/* IA32_RTIT_CTL MSR bits */
  30#define INTEL_PT_CYC_ENABLE		BITULL(1)
  31#define INTEL_PT_CYC_THRESHOLD		(BITULL(22) | BITULL(21) | BITULL(20) | BITULL(19))
  32#define INTEL_PT_CYC_THRESHOLD_SHIFT	19
  33
  34#define INTEL_PT_BLK_SIZE 1024
  35
  36#define BIT63 (((uint64_t)1 << 63))
  37
  38#define SEVEN_BYTES 0xffffffffffffffULL
  39
  40#define NO_VMCS 0xffffffffffULL
  41
  42#define INTEL_PT_RETURN 1
  43
  44/*
  45 * Default maximum number of loops with no packets consumed i.e. stuck in a
  46 * loop.
  47 */
  48#define INTEL_PT_MAX_LOOPS 100000
  49
  50struct intel_pt_blk {
  51	struct intel_pt_blk *prev;
  52	uint64_t ip[INTEL_PT_BLK_SIZE];
  53};
  54
  55struct intel_pt_stack {
  56	struct intel_pt_blk *blk;
  57	struct intel_pt_blk *spare;
  58	int pos;
  59};
  60
  61enum intel_pt_p_once {
  62	INTEL_PT_PRT_ONCE_UNK_VMCS,
  63	INTEL_PT_PRT_ONCE_ERANGE,
  64};
  65
  66enum intel_pt_pkt_state {
  67	INTEL_PT_STATE_NO_PSB,
  68	INTEL_PT_STATE_NO_IP,
  69	INTEL_PT_STATE_ERR_RESYNC,
  70	INTEL_PT_STATE_IN_SYNC,
  71	INTEL_PT_STATE_TNT_CONT,
  72	INTEL_PT_STATE_TNT,
  73	INTEL_PT_STATE_TIP,
  74	INTEL_PT_STATE_TIP_PGD,
  75	INTEL_PT_STATE_FUP,
  76	INTEL_PT_STATE_FUP_NO_TIP,
  77	INTEL_PT_STATE_FUP_IN_PSB,
  78	INTEL_PT_STATE_RESAMPLE,
  79	INTEL_PT_STATE_VM_TIME_CORRELATION,
  80};
  81
  82static inline bool intel_pt_sample_time(enum intel_pt_pkt_state pkt_state)
  83{
  84	switch (pkt_state) {
  85	case INTEL_PT_STATE_NO_PSB:
  86	case INTEL_PT_STATE_NO_IP:
  87	case INTEL_PT_STATE_ERR_RESYNC:
  88	case INTEL_PT_STATE_IN_SYNC:
  89	case INTEL_PT_STATE_TNT_CONT:
  90	case INTEL_PT_STATE_RESAMPLE:
  91	case INTEL_PT_STATE_VM_TIME_CORRELATION:
  92		return true;
  93	case INTEL_PT_STATE_TNT:
  94	case INTEL_PT_STATE_TIP:
  95	case INTEL_PT_STATE_TIP_PGD:
  96	case INTEL_PT_STATE_FUP:
  97	case INTEL_PT_STATE_FUP_NO_TIP:
  98	case INTEL_PT_STATE_FUP_IN_PSB:
  99		return false;
 100	default:
 101		return true;
 102	};
 103}
 104
 105#ifdef INTEL_PT_STRICT
 106#define INTEL_PT_STATE_ERR1	INTEL_PT_STATE_NO_PSB
 107#define INTEL_PT_STATE_ERR2	INTEL_PT_STATE_NO_PSB
 108#define INTEL_PT_STATE_ERR3	INTEL_PT_STATE_NO_PSB
 109#define INTEL_PT_STATE_ERR4	INTEL_PT_STATE_NO_PSB
 110#else
 111#define INTEL_PT_STATE_ERR1	(decoder->pkt_state)
 112#define INTEL_PT_STATE_ERR2	INTEL_PT_STATE_NO_IP
 113#define INTEL_PT_STATE_ERR3	INTEL_PT_STATE_ERR_RESYNC
 114#define INTEL_PT_STATE_ERR4	INTEL_PT_STATE_IN_SYNC
 115#endif
 116
 117struct intel_pt_decoder {
 118	int (*get_trace)(struct intel_pt_buffer *buffer, void *data);
 119	int (*walk_insn)(struct intel_pt_insn *intel_pt_insn,
 120			 uint64_t *insn_cnt_ptr, uint64_t *ip, uint64_t to_ip,
 121			 uint64_t max_insn_cnt, void *data);
 122	bool (*pgd_ip)(uint64_t ip, void *data);
 123	int (*lookahead)(void *data, intel_pt_lookahead_cb_t cb, void *cb_data);
 124	struct intel_pt_vmcs_info *(*findnew_vmcs_info)(void *data, uint64_t vmcs);
 125	void *data;
 126	struct intel_pt_state state;
 127	const unsigned char *buf;
 128	size_t len;
 129	bool return_compression;
 130	bool branch_enable;
 131	bool mtc_insn;
 132	bool pge;
 133	bool have_tma;
 134	bool have_cyc;
 135	bool fixup_last_mtc;
 136	bool have_last_ip;
 137	bool in_psb;
 138	bool hop;
 
 139	bool leap;
 140	bool emulated_ptwrite;
 141	bool vm_time_correlation;
 142	bool vm_tm_corr_dry_run;
 143	bool vm_tm_corr_reliable;
 144	bool vm_tm_corr_same_buf;
 145	bool vm_tm_corr_continuous;
 146	bool nr;
 147	bool next_nr;
 148	bool iflag;
 149	bool next_iflag;
 150	enum intel_pt_param_flags flags;
 151	uint64_t pos;
 152	uint64_t last_ip;
 153	uint64_t ip;
 154	uint64_t pip_payload;
 155	uint64_t timestamp;
 156	uint64_t tsc_timestamp;
 157	uint64_t ref_timestamp;
 158	uint64_t buf_timestamp;
 159	uint64_t sample_timestamp;
 160	uint64_t ret_addr;
 161	uint64_t ctc_timestamp;
 162	uint64_t ctc_delta;
 163	uint64_t cycle_cnt;
 164	uint64_t cyc_ref_timestamp;
 165	uint64_t first_timestamp;
 166	uint64_t last_reliable_timestamp;
 167	uint64_t vmcs;
 168	uint64_t print_once;
 169	uint64_t last_ctc;
 170	uint32_t last_mtc;
 171	uint32_t tsc_ctc_ratio_n;
 172	uint32_t tsc_ctc_ratio_d;
 173	uint32_t tsc_ctc_mult;
 174	uint32_t tsc_slip;
 175	uint32_t ctc_rem_mask;
 176	int mtc_shift;
 177	struct intel_pt_stack stack;
 178	enum intel_pt_pkt_state pkt_state;
 179	enum intel_pt_pkt_ctx pkt_ctx;
 180	enum intel_pt_pkt_ctx prev_pkt_ctx;
 181	enum intel_pt_blk_type blk_type;
 182	int blk_type_pos;
 183	struct intel_pt_pkt packet;
 184	struct intel_pt_pkt tnt;
 185	int pkt_step;
 186	int pkt_len;
 187	int last_packet_type;
 188	unsigned int cbr;
 189	unsigned int cbr_seen;
 190	unsigned int max_non_turbo_ratio;
 191	double max_non_turbo_ratio_fp;
 192	double cbr_cyc_to_tsc;
 193	double calc_cyc_to_tsc;
 194	bool have_calc_cyc_to_tsc;
 195	int exec_mode;
 196	unsigned int insn_bytes;
 197	uint64_t period;
 198	enum intel_pt_period_type period_type;
 199	uint64_t tot_insn_cnt;
 200	uint64_t period_insn_cnt;
 201	uint64_t period_mask;
 202	uint64_t period_ticks;
 203	uint64_t last_masked_timestamp;
 204	uint64_t tot_cyc_cnt;
 205	uint64_t sample_tot_cyc_cnt;
 206	uint64_t base_cyc_cnt;
 207	uint64_t cyc_cnt_timestamp;
 208	uint64_t ctl;
 209	uint64_t cyc_threshold;
 210	double tsc_to_cyc;
 211	bool continuous_period;
 212	bool overflow;
 213	bool set_fup_tx_flags;
 214	bool set_fup_ptw;
 215	bool set_fup_mwait;
 216	bool set_fup_pwre;
 217	bool set_fup_exstop;
 218	bool set_fup_bep;
 219	bool set_fup_cfe_ip;
 220	bool set_fup_cfe;
 221	bool set_fup_mode_exec;
 222	bool sample_cyc;
 223	unsigned int fup_tx_flags;
 224	unsigned int tx_flags;
 225	uint64_t fup_ptw_payload;
 226	uint64_t fup_mwait_payload;
 227	uint64_t fup_pwre_payload;
 228	uint64_t cbr_payload;
 229	uint64_t timestamp_insn_cnt;
 230	uint64_t sample_insn_cnt;
 231	uint64_t stuck_ip;
 232	struct intel_pt_pkt fup_cfe_pkt;
 233	int max_loops;
 234	int no_progress;
 235	int stuck_ip_prd;
 236	int stuck_ip_cnt;
 237	uint64_t psb_ip;
 238	const unsigned char *next_buf;
 239	size_t next_len;
 240	unsigned char temp_buf[INTEL_PT_PKT_MAX_SZ];
 241	int evd_cnt;
 242	struct intel_pt_evd evd[INTEL_PT_MAX_EVDS];
 243};
 244
 245static uint64_t intel_pt_lower_power_of_2(uint64_t x)
 246{
 247	int i;
 248
 249	for (i = 0; x != 1; i++)
 250		x >>= 1;
 251
 252	return x << i;
 253}
 254
 255__printf(1, 2)
 256static void p_log(const char *fmt, ...)
 257{
 258	char buf[512];
 259	va_list args;
 260
 261	va_start(args, fmt);
 262	vsnprintf(buf, sizeof(buf), fmt, args);
 263	va_end(args);
 264
 265	fprintf(stderr, "%s\n", buf);
 266	intel_pt_log("%s\n", buf);
 267}
 268
 269static bool intel_pt_print_once(struct intel_pt_decoder *decoder,
 270				enum intel_pt_p_once id)
 271{
 272	uint64_t bit = 1ULL << id;
 273
 274	if (decoder->print_once & bit)
 275		return false;
 276	decoder->print_once |= bit;
 277	return true;
 278}
 279
 280static uint64_t intel_pt_cyc_threshold(uint64_t ctl)
 281{
 282	if (!(ctl & INTEL_PT_CYC_ENABLE))
 283		return 0;
 284
 285	return (ctl & INTEL_PT_CYC_THRESHOLD) >> INTEL_PT_CYC_THRESHOLD_SHIFT;
 286}
 287
 288static void intel_pt_setup_period(struct intel_pt_decoder *decoder)
 289{
 290	if (decoder->period_type == INTEL_PT_PERIOD_TICKS) {
 291		uint64_t period;
 292
 293		period = intel_pt_lower_power_of_2(decoder->period);
 294		decoder->period_mask  = ~(period - 1);
 295		decoder->period_ticks = period;
 296	}
 297}
 298
 299static uint64_t multdiv(uint64_t t, uint32_t n, uint32_t d)
 300{
 301	if (!d)
 302		return 0;
 303	return (t / d) * n + ((t % d) * n) / d;
 304}
 305
 306struct intel_pt_decoder *intel_pt_decoder_new(struct intel_pt_params *params)
 307{
 308	struct intel_pt_decoder *decoder;
 309
 310	if (!params->get_trace || !params->walk_insn)
 311		return NULL;
 312
 313	decoder = zalloc(sizeof(struct intel_pt_decoder));
 314	if (!decoder)
 315		return NULL;
 316
 317	decoder->get_trace          = params->get_trace;
 318	decoder->walk_insn          = params->walk_insn;
 319	decoder->pgd_ip             = params->pgd_ip;
 320	decoder->lookahead          = params->lookahead;
 321	decoder->findnew_vmcs_info  = params->findnew_vmcs_info;
 322	decoder->data               = params->data;
 323	decoder->return_compression = params->return_compression;
 324	decoder->branch_enable      = params->branch_enable;
 325	decoder->hop                = params->quick >= 1;
 326	decoder->leap               = params->quick >= 2;
 327	decoder->vm_time_correlation = params->vm_time_correlation;
 328	decoder->vm_tm_corr_dry_run = params->vm_tm_corr_dry_run;
 329	decoder->first_timestamp    = params->first_timestamp;
 330	decoder->last_reliable_timestamp = params->first_timestamp;
 331	decoder->max_loops          = params->max_loops ? params->max_loops : INTEL_PT_MAX_LOOPS;
 332
 333	decoder->flags              = params->flags;
 334
 335	decoder->ctl                = params->ctl;
 336	decoder->period             = params->period;
 337	decoder->period_type        = params->period_type;
 338
 339	decoder->max_non_turbo_ratio    = params->max_non_turbo_ratio;
 340	decoder->max_non_turbo_ratio_fp = params->max_non_turbo_ratio;
 341
 342	decoder->cyc_threshold = intel_pt_cyc_threshold(decoder->ctl);
 343
 344	intel_pt_setup_period(decoder);
 345
 346	decoder->mtc_shift = params->mtc_period;
 347	decoder->ctc_rem_mask = (1 << decoder->mtc_shift) - 1;
 348
 349	decoder->tsc_ctc_ratio_n = params->tsc_ctc_ratio_n;
 350	decoder->tsc_ctc_ratio_d = params->tsc_ctc_ratio_d;
 351
 352	if (!decoder->tsc_ctc_ratio_n)
 353		decoder->tsc_ctc_ratio_d = 0;
 354
 355	if (decoder->tsc_ctc_ratio_d) {
 356		if (!(decoder->tsc_ctc_ratio_n % decoder->tsc_ctc_ratio_d))
 357			decoder->tsc_ctc_mult = decoder->tsc_ctc_ratio_n /
 358						decoder->tsc_ctc_ratio_d;
 359	}
 360
 361	/*
 362	 * A TSC packet can slip past MTC packets so that the timestamp appears
 363	 * to go backwards. One estimate is that can be up to about 40 CPU
 364	 * cycles, which is certainly less than 0x1000 TSC ticks, but accept
 365	 * slippage an order of magnitude more to be on the safe side.
 366	 */
 367	decoder->tsc_slip = 0x10000;
 368
 369	intel_pt_log("timestamp: mtc_shift %u\n", decoder->mtc_shift);
 370	intel_pt_log("timestamp: tsc_ctc_ratio_n %u\n", decoder->tsc_ctc_ratio_n);
 371	intel_pt_log("timestamp: tsc_ctc_ratio_d %u\n", decoder->tsc_ctc_ratio_d);
 372	intel_pt_log("timestamp: tsc_ctc_mult %u\n", decoder->tsc_ctc_mult);
 373	intel_pt_log("timestamp: tsc_slip %#x\n", decoder->tsc_slip);
 374
 375	if (decoder->hop)
 376		intel_pt_log("Hop mode: decoding FUP and TIPs, but not TNT\n");
 377
 378	return decoder;
 379}
 380
 381void intel_pt_set_first_timestamp(struct intel_pt_decoder *decoder,
 382				  uint64_t first_timestamp)
 383{
 384	decoder->first_timestamp = first_timestamp;
 385}
 386
 387static void intel_pt_pop_blk(struct intel_pt_stack *stack)
 388{
 389	struct intel_pt_blk *blk = stack->blk;
 390
 391	stack->blk = blk->prev;
 392	if (!stack->spare)
 393		stack->spare = blk;
 394	else
 395		free(blk);
 396}
 397
 398static uint64_t intel_pt_pop(struct intel_pt_stack *stack)
 399{
 400	if (!stack->pos) {
 401		if (!stack->blk)
 402			return 0;
 403		intel_pt_pop_blk(stack);
 404		if (!stack->blk)
 405			return 0;
 406		stack->pos = INTEL_PT_BLK_SIZE;
 407	}
 408	return stack->blk->ip[--stack->pos];
 409}
 410
 411static int intel_pt_alloc_blk(struct intel_pt_stack *stack)
 412{
 413	struct intel_pt_blk *blk;
 414
 415	if (stack->spare) {
 416		blk = stack->spare;
 417		stack->spare = NULL;
 418	} else {
 419		blk = malloc(sizeof(struct intel_pt_blk));
 420		if (!blk)
 421			return -ENOMEM;
 422	}
 423
 424	blk->prev = stack->blk;
 425	stack->blk = blk;
 426	stack->pos = 0;
 427	return 0;
 428}
 429
 430static int intel_pt_push(struct intel_pt_stack *stack, uint64_t ip)
 431{
 432	int err;
 433
 434	if (!stack->blk || stack->pos == INTEL_PT_BLK_SIZE) {
 435		err = intel_pt_alloc_blk(stack);
 436		if (err)
 437			return err;
 438	}
 439
 440	stack->blk->ip[stack->pos++] = ip;
 441	return 0;
 442}
 443
 444static void intel_pt_clear_stack(struct intel_pt_stack *stack)
 445{
 446	while (stack->blk)
 447		intel_pt_pop_blk(stack);
 448	stack->pos = 0;
 449}
 450
 451static void intel_pt_free_stack(struct intel_pt_stack *stack)
 452{
 453	intel_pt_clear_stack(stack);
 454	zfree(&stack->blk);
 455	zfree(&stack->spare);
 456}
 457
 458void intel_pt_decoder_free(struct intel_pt_decoder *decoder)
 459{
 460	intel_pt_free_stack(&decoder->stack);
 461	free(decoder);
 462}
 463
 464static int intel_pt_ext_err(int code)
 465{
 466	switch (code) {
 467	case -ENOMEM:
 468		return INTEL_PT_ERR_NOMEM;
 469	case -ENOSYS:
 470		return INTEL_PT_ERR_INTERN;
 471	case -EBADMSG:
 472		return INTEL_PT_ERR_BADPKT;
 473	case -ENODATA:
 474		return INTEL_PT_ERR_NODATA;
 475	case -EILSEQ:
 476		return INTEL_PT_ERR_NOINSN;
 477	case -ENOENT:
 478		return INTEL_PT_ERR_MISMAT;
 479	case -EOVERFLOW:
 480		return INTEL_PT_ERR_OVR;
 481	case -ENOSPC:
 482		return INTEL_PT_ERR_LOST;
 483	case -ELOOP:
 484		return INTEL_PT_ERR_NELOOP;
 485	case -ECONNRESET:
 486		return INTEL_PT_ERR_EPTW;
 487	default:
 488		return INTEL_PT_ERR_UNK;
 489	}
 490}
 491
 492static const char *intel_pt_err_msgs[] = {
 493	[INTEL_PT_ERR_NOMEM]  = "Memory allocation failed",
 494	[INTEL_PT_ERR_INTERN] = "Internal error",
 495	[INTEL_PT_ERR_BADPKT] = "Bad packet",
 496	[INTEL_PT_ERR_NODATA] = "No more data",
 497	[INTEL_PT_ERR_NOINSN] = "Failed to get instruction",
 498	[INTEL_PT_ERR_MISMAT] = "Trace doesn't match instruction",
 499	[INTEL_PT_ERR_OVR]    = "Overflow packet",
 500	[INTEL_PT_ERR_LOST]   = "Lost trace data",
 501	[INTEL_PT_ERR_UNK]    = "Unknown error!",
 502	[INTEL_PT_ERR_NELOOP] = "Never-ending loop (refer perf config intel-pt.max-loops)",
 503	[INTEL_PT_ERR_EPTW]   = "Broken emulated ptwrite",
 504};
 505
 506int intel_pt__strerror(int code, char *buf, size_t buflen)
 507{
 508	if (code < 1 || code >= INTEL_PT_ERR_MAX)
 509		code = INTEL_PT_ERR_UNK;
 510	strlcpy(buf, intel_pt_err_msgs[code], buflen);
 511	return 0;
 512}
 513
 514static uint64_t intel_pt_calc_ip(const struct intel_pt_pkt *packet,
 515				 uint64_t last_ip)
 516{
 517	uint64_t ip;
 518
 519	switch (packet->count) {
 520	case 1:
 521		ip = (last_ip & (uint64_t)0xffffffffffff0000ULL) |
 522		     packet->payload;
 523		break;
 524	case 2:
 525		ip = (last_ip & (uint64_t)0xffffffff00000000ULL) |
 526		     packet->payload;
 527		break;
 528	case 3:
 529		ip = packet->payload;
 530		/* Sign-extend 6-byte ip */
 531		if (ip & (uint64_t)0x800000000000ULL)
 532			ip |= (uint64_t)0xffff000000000000ULL;
 533		break;
 534	case 4:
 535		ip = (last_ip & (uint64_t)0xffff000000000000ULL) |
 536		     packet->payload;
 537		break;
 538	case 6:
 539		ip = packet->payload;
 540		break;
 541	default:
 542		return 0;
 543	}
 544
 545	return ip;
 546}
 547
 548static inline void intel_pt_set_last_ip(struct intel_pt_decoder *decoder)
 549{
 550	decoder->last_ip = intel_pt_calc_ip(&decoder->packet, decoder->last_ip);
 551	decoder->have_last_ip = true;
 552}
 553
 554static inline void intel_pt_set_ip(struct intel_pt_decoder *decoder)
 555{
 556	intel_pt_set_last_ip(decoder);
 557	decoder->ip = decoder->last_ip;
 558}
 559
 560static void intel_pt_decoder_log_packet(struct intel_pt_decoder *decoder)
 561{
 562	intel_pt_log_packet(&decoder->packet, decoder->pkt_len, decoder->pos,
 563			    decoder->buf);
 564}
 565
 566static int intel_pt_bug(struct intel_pt_decoder *decoder)
 567{
 568	intel_pt_log("ERROR: Internal error\n");
 569	decoder->pkt_state = INTEL_PT_STATE_NO_PSB;
 570	return -ENOSYS;
 571}
 572
 573static inline void intel_pt_clear_tx_flags(struct intel_pt_decoder *decoder)
 574{
 575	decoder->tx_flags = 0;
 576}
 577
 578static inline void intel_pt_update_in_tx(struct intel_pt_decoder *decoder)
 579{
 580	decoder->tx_flags = decoder->packet.payload & INTEL_PT_IN_TX;
 581}
 582
 583static inline void intel_pt_update_pip(struct intel_pt_decoder *decoder)
 584{
 585	decoder->pip_payload = decoder->packet.payload;
 586}
 587
 588static inline void intel_pt_update_nr(struct intel_pt_decoder *decoder)
 589{
 590	decoder->next_nr = decoder->pip_payload & 1;
 591}
 592
 593static inline void intel_pt_set_nr(struct intel_pt_decoder *decoder)
 594{
 595	decoder->nr = decoder->pip_payload & 1;
 596	decoder->next_nr = decoder->nr;
 597}
 598
 599static inline void intel_pt_set_pip(struct intel_pt_decoder *decoder)
 600{
 601	intel_pt_update_pip(decoder);
 602	intel_pt_set_nr(decoder);
 603}
 604
 605static int intel_pt_bad_packet(struct intel_pt_decoder *decoder)
 606{
 607	intel_pt_clear_tx_flags(decoder);
 608	decoder->have_tma = false;
 609	decoder->pkt_len = 1;
 610	decoder->pkt_step = 1;
 611	intel_pt_decoder_log_packet(decoder);
 612	if (decoder->pkt_state != INTEL_PT_STATE_NO_PSB) {
 613		intel_pt_log("ERROR: Bad packet\n");
 614		decoder->pkt_state = INTEL_PT_STATE_ERR1;
 615	}
 616	return -EBADMSG;
 617}
 618
 619static inline void intel_pt_update_sample_time(struct intel_pt_decoder *decoder)
 620{
 621	decoder->sample_timestamp = decoder->timestamp;
 622	decoder->sample_insn_cnt = decoder->timestamp_insn_cnt;
 623	decoder->state.cycles = decoder->tot_cyc_cnt;
 624}
 625
 626static void intel_pt_reposition(struct intel_pt_decoder *decoder)
 627{
 628	decoder->ip = 0;
 629	decoder->pkt_state = INTEL_PT_STATE_NO_PSB;
 630	decoder->timestamp = 0;
 631	decoder->have_tma = false;
 632}
 633
 634static int intel_pt_get_data(struct intel_pt_decoder *decoder, bool reposition)
 635{
 636	struct intel_pt_buffer buffer = { .buf = 0, };
 637	int ret;
 638
 639	decoder->pkt_step = 0;
 640
 641	intel_pt_log("Getting more data\n");
 642	ret = decoder->get_trace(&buffer, decoder->data);
 643	if (ret)
 644		return ret;
 645	decoder->buf = buffer.buf;
 646	decoder->len = buffer.len;
 647	if (!decoder->len) {
 648		intel_pt_log("No more data\n");
 649		return -ENODATA;
 650	}
 651	decoder->buf_timestamp = buffer.ref_timestamp;
 652	if (!buffer.consecutive || reposition) {
 653		intel_pt_reposition(decoder);
 654		decoder->ref_timestamp = buffer.ref_timestamp;
 655		decoder->state.trace_nr = buffer.trace_nr;
 656		decoder->vm_tm_corr_same_buf = false;
 657		intel_pt_log("Reference timestamp 0x%" PRIx64 "\n",
 658			     decoder->ref_timestamp);
 659		return -ENOLINK;
 660	}
 661
 662	return 0;
 663}
 664
 665static int intel_pt_get_next_data(struct intel_pt_decoder *decoder,
 666				  bool reposition)
 667{
 668	if (!decoder->next_buf)
 669		return intel_pt_get_data(decoder, reposition);
 670
 671	decoder->buf = decoder->next_buf;
 672	decoder->len = decoder->next_len;
 673	decoder->next_buf = 0;
 674	decoder->next_len = 0;
 675	return 0;
 676}
 677
 678static int intel_pt_get_split_packet(struct intel_pt_decoder *decoder)
 679{
 680	unsigned char *buf = decoder->temp_buf;
 681	size_t old_len, len, n;
 682	int ret;
 683
 684	old_len = decoder->len;
 685	len = decoder->len;
 686	memcpy(buf, decoder->buf, len);
 687
 688	ret = intel_pt_get_data(decoder, false);
 689	if (ret) {
 690		decoder->pos += old_len;
 691		return ret < 0 ? ret : -EINVAL;
 692	}
 693
 694	n = INTEL_PT_PKT_MAX_SZ - len;
 695	if (n > decoder->len)
 696		n = decoder->len;
 697	memcpy(buf + len, decoder->buf, n);
 698	len += n;
 699
 700	decoder->prev_pkt_ctx = decoder->pkt_ctx;
 701	ret = intel_pt_get_packet(buf, len, &decoder->packet, &decoder->pkt_ctx);
 702	if (ret < (int)old_len) {
 703		decoder->next_buf = decoder->buf;
 704		decoder->next_len = decoder->len;
 705		decoder->buf = buf;
 706		decoder->len = old_len;
 707		return intel_pt_bad_packet(decoder);
 708	}
 709
 710	decoder->next_buf = decoder->buf + (ret - old_len);
 711	decoder->next_len = decoder->len - (ret - old_len);
 712
 713	decoder->buf = buf;
 714	decoder->len = ret;
 715
 716	return ret;
 717}
 718
 719struct intel_pt_pkt_info {
 720	struct intel_pt_decoder	  *decoder;
 721	struct intel_pt_pkt       packet;
 722	uint64_t                  pos;
 723	int                       pkt_len;
 724	int                       last_packet_type;
 725	void                      *data;
 726};
 727
 728typedef int (*intel_pt_pkt_cb_t)(struct intel_pt_pkt_info *pkt_info);
 729
 730/* Lookahead packets in current buffer */
 731static int intel_pt_pkt_lookahead(struct intel_pt_decoder *decoder,
 732				  intel_pt_pkt_cb_t cb, void *data)
 733{
 734	struct intel_pt_pkt_info pkt_info;
 735	const unsigned char *buf = decoder->buf;
 736	enum intel_pt_pkt_ctx pkt_ctx = decoder->pkt_ctx;
 737	size_t len = decoder->len;
 738	int ret;
 739
 740	pkt_info.decoder          = decoder;
 741	pkt_info.pos              = decoder->pos;
 742	pkt_info.pkt_len          = decoder->pkt_step;
 743	pkt_info.last_packet_type = decoder->last_packet_type;
 744	pkt_info.data             = data;
 745
 746	while (1) {
 747		do {
 748			pkt_info.pos += pkt_info.pkt_len;
 749			buf          += pkt_info.pkt_len;
 750			len          -= pkt_info.pkt_len;
 751
 752			if (!len)
 753				return INTEL_PT_NEED_MORE_BYTES;
 754
 755			ret = intel_pt_get_packet(buf, len, &pkt_info.packet,
 756						  &pkt_ctx);
 757			if (!ret)
 758				return INTEL_PT_NEED_MORE_BYTES;
 759			if (ret < 0)
 760				return ret;
 761
 762			pkt_info.pkt_len = ret;
 763		} while (pkt_info.packet.type == INTEL_PT_PAD);
 764
 765		ret = cb(&pkt_info);
 766		if (ret)
 767			return 0;
 768
 769		pkt_info.last_packet_type = pkt_info.packet.type;
 770	}
 771}
 772
 773struct intel_pt_calc_cyc_to_tsc_info {
 774	uint64_t        cycle_cnt;
 775	unsigned int    cbr;
 776	uint32_t        last_mtc;
 777	uint64_t        ctc_timestamp;
 778	uint64_t        ctc_delta;
 779	uint64_t        tsc_timestamp;
 780	uint64_t        timestamp;
 781	bool            have_tma;
 782	bool            fixup_last_mtc;
 783	bool            from_mtc;
 784	double          cbr_cyc_to_tsc;
 785};
 786
 787/*
 788 * MTC provides a 8-bit slice of CTC but the TMA packet only provides the lower
 789 * 16 bits of CTC. If mtc_shift > 8 then some of the MTC bits are not in the CTC
 790 * provided by the TMA packet. Fix-up the last_mtc calculated from the TMA
 791 * packet by copying the missing bits from the current MTC assuming the least
 792 * difference between the two, and that the current MTC comes after last_mtc.
 793 */
 794static void intel_pt_fixup_last_mtc(uint32_t mtc, int mtc_shift,
 795				    uint32_t *last_mtc)
 796{
 797	uint32_t first_missing_bit = 1U << (16 - mtc_shift);
 798	uint32_t mask = ~(first_missing_bit - 1);
 799
 800	*last_mtc |= mtc & mask;
 801	if (*last_mtc >= mtc) {
 802		*last_mtc -= first_missing_bit;
 803		*last_mtc &= 0xff;
 804	}
 805}
 806
 807static int intel_pt_calc_cyc_cb(struct intel_pt_pkt_info *pkt_info)
 808{
 809	struct intel_pt_decoder *decoder = pkt_info->decoder;
 810	struct intel_pt_calc_cyc_to_tsc_info *data = pkt_info->data;
 811	uint64_t timestamp;
 812	double cyc_to_tsc;
 813	unsigned int cbr;
 814	uint32_t mtc, mtc_delta, ctc, fc, ctc_rem;
 815
 816	switch (pkt_info->packet.type) {
 817	case INTEL_PT_TNT:
 818	case INTEL_PT_TIP_PGE:
 819	case INTEL_PT_TIP:
 820	case INTEL_PT_FUP:
 821	case INTEL_PT_PSB:
 822	case INTEL_PT_PIP:
 823	case INTEL_PT_MODE_EXEC:
 824	case INTEL_PT_MODE_TSX:
 825	case INTEL_PT_PSBEND:
 826	case INTEL_PT_PAD:
 827	case INTEL_PT_VMCS:
 828	case INTEL_PT_MNT:
 829	case INTEL_PT_PTWRITE:
 830	case INTEL_PT_PTWRITE_IP:
 831	case INTEL_PT_BBP:
 832	case INTEL_PT_BIP:
 833	case INTEL_PT_BEP:
 834	case INTEL_PT_BEP_IP:
 835	case INTEL_PT_CFE:
 836	case INTEL_PT_CFE_IP:
 837	case INTEL_PT_EVD:
 838		return 0;
 839
 840	case INTEL_PT_MTC:
 841		if (!data->have_tma)
 842			return 0;
 843
 844		mtc = pkt_info->packet.payload;
 845		if (decoder->mtc_shift > 8 && data->fixup_last_mtc) {
 846			data->fixup_last_mtc = false;
 847			intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
 848						&data->last_mtc);
 849		}
 850		if (mtc > data->last_mtc)
 851			mtc_delta = mtc - data->last_mtc;
 852		else
 853			mtc_delta = mtc + 256 - data->last_mtc;
 854		data->ctc_delta += mtc_delta << decoder->mtc_shift;
 855		data->last_mtc = mtc;
 856
 857		if (decoder->tsc_ctc_mult) {
 858			timestamp = data->ctc_timestamp +
 859				data->ctc_delta * decoder->tsc_ctc_mult;
 860		} else {
 861			timestamp = data->ctc_timestamp +
 862				multdiv(data->ctc_delta,
 863					decoder->tsc_ctc_ratio_n,
 864					decoder->tsc_ctc_ratio_d);
 865		}
 866
 867		if (timestamp < data->timestamp)
 868			return 1;
 869
 870		if (pkt_info->last_packet_type != INTEL_PT_CYC) {
 871			data->timestamp = timestamp;
 872			return 0;
 873		}
 874
 875		break;
 876
 877	case INTEL_PT_TSC:
 878		/*
 879		 * For now, do not support using TSC packets - refer
 880		 * intel_pt_calc_cyc_to_tsc().
 881		 */
 882		if (data->from_mtc)
 883			return 1;
 884		timestamp = pkt_info->packet.payload |
 885			    (data->timestamp & (0xffULL << 56));
 886		if (data->from_mtc && timestamp < data->timestamp &&
 887		    data->timestamp - timestamp < decoder->tsc_slip)
 888			return 1;
 889		if (timestamp < data->timestamp)
 890			timestamp += (1ULL << 56);
 891		if (pkt_info->last_packet_type != INTEL_PT_CYC) {
 892			if (data->from_mtc)
 893				return 1;
 894			data->tsc_timestamp = timestamp;
 895			data->timestamp = timestamp;
 896			return 0;
 897		}
 898		break;
 899
 900	case INTEL_PT_TMA:
 901		if (data->from_mtc)
 902			return 1;
 903
 904		if (!decoder->tsc_ctc_ratio_d)
 905			return 0;
 906
 907		ctc = pkt_info->packet.payload;
 908		fc = pkt_info->packet.count;
 909		ctc_rem = ctc & decoder->ctc_rem_mask;
 910
 911		data->last_mtc = (ctc >> decoder->mtc_shift) & 0xff;
 912
 913		data->ctc_timestamp = data->tsc_timestamp - fc;
 914		if (decoder->tsc_ctc_mult) {
 915			data->ctc_timestamp -= ctc_rem * decoder->tsc_ctc_mult;
 916		} else {
 917			data->ctc_timestamp -=
 918				multdiv(ctc_rem, decoder->tsc_ctc_ratio_n,
 919					decoder->tsc_ctc_ratio_d);
 920		}
 921
 922		data->ctc_delta = 0;
 923		data->have_tma = true;
 924		data->fixup_last_mtc = true;
 925
 926		return 0;
 927
 928	case INTEL_PT_CYC:
 929		data->cycle_cnt += pkt_info->packet.payload;
 930		return 0;
 931
 932	case INTEL_PT_CBR:
 933		cbr = pkt_info->packet.payload;
 934		if (data->cbr && data->cbr != cbr)
 935			return 1;
 936		data->cbr = cbr;
 937		data->cbr_cyc_to_tsc = decoder->max_non_turbo_ratio_fp / cbr;
 938		return 0;
 939
 940	case INTEL_PT_TIP_PGD:
 941	case INTEL_PT_TRACESTOP:
 942	case INTEL_PT_EXSTOP:
 943	case INTEL_PT_EXSTOP_IP:
 944	case INTEL_PT_MWAIT:
 945	case INTEL_PT_PWRE:
 946	case INTEL_PT_PWRX:
 947	case INTEL_PT_OVF:
 948	case INTEL_PT_BAD: /* Does not happen */
 949	default:
 950		return 1;
 951	}
 952
 953	if (!data->cbr && decoder->cbr) {
 954		data->cbr = decoder->cbr;
 955		data->cbr_cyc_to_tsc = decoder->cbr_cyc_to_tsc;
 956	}
 957
 958	if (!data->cycle_cnt)
 959		return 1;
 960
 961	cyc_to_tsc = (double)(timestamp - decoder->timestamp) / data->cycle_cnt;
 962
 963	if (data->cbr && cyc_to_tsc > data->cbr_cyc_to_tsc &&
 964	    cyc_to_tsc / data->cbr_cyc_to_tsc > 1.25) {
 965		intel_pt_log("Timestamp: calculated %g TSC ticks per cycle too big (c.f. CBR-based value %g), pos " x64_fmt "\n",
 966			     cyc_to_tsc, data->cbr_cyc_to_tsc, pkt_info->pos);
 967		return 1;
 968	}
 969
 970	decoder->calc_cyc_to_tsc = cyc_to_tsc;
 971	decoder->have_calc_cyc_to_tsc = true;
 972
 973	if (data->cbr) {
 974		intel_pt_log("Timestamp: calculated %g TSC ticks per cycle c.f. CBR-based value %g, pos " x64_fmt "\n",
 975			     cyc_to_tsc, data->cbr_cyc_to_tsc, pkt_info->pos);
 976	} else {
 977		intel_pt_log("Timestamp: calculated %g TSC ticks per cycle c.f. unknown CBR-based value, pos " x64_fmt "\n",
 978			     cyc_to_tsc, pkt_info->pos);
 979	}
 980
 981	return 1;
 982}
 983
 984static void intel_pt_calc_cyc_to_tsc(struct intel_pt_decoder *decoder,
 985				     bool from_mtc)
 986{
 987	struct intel_pt_calc_cyc_to_tsc_info data = {
 988		.cycle_cnt      = 0,
 989		.cbr            = 0,
 990		.last_mtc       = decoder->last_mtc,
 991		.ctc_timestamp  = decoder->ctc_timestamp,
 992		.ctc_delta      = decoder->ctc_delta,
 993		.tsc_timestamp  = decoder->tsc_timestamp,
 994		.timestamp      = decoder->timestamp,
 995		.have_tma       = decoder->have_tma,
 996		.fixup_last_mtc = decoder->fixup_last_mtc,
 997		.from_mtc       = from_mtc,
 998		.cbr_cyc_to_tsc = 0,
 999	};
1000
1001	/*
1002	 * For now, do not support using TSC packets for at least the reasons:
1003	 * 1) timing might have stopped
1004	 * 2) TSC packets within PSB+ can slip against CYC packets
1005	 */
1006	if (!from_mtc)
1007		return;
1008
1009	intel_pt_pkt_lookahead(decoder, intel_pt_calc_cyc_cb, &data);
1010}
1011
1012static int intel_pt_get_next_packet(struct intel_pt_decoder *decoder)
1013{
1014	int ret;
1015
1016	decoder->last_packet_type = decoder->packet.type;
1017
1018	do {
1019		decoder->pos += decoder->pkt_step;
1020		decoder->buf += decoder->pkt_step;
1021		decoder->len -= decoder->pkt_step;
1022
1023		if (!decoder->len) {
1024			ret = intel_pt_get_next_data(decoder, false);
1025			if (ret)
1026				return ret;
1027		}
1028
1029		decoder->prev_pkt_ctx = decoder->pkt_ctx;
1030		ret = intel_pt_get_packet(decoder->buf, decoder->len,
1031					  &decoder->packet, &decoder->pkt_ctx);
1032		if (ret == INTEL_PT_NEED_MORE_BYTES && BITS_PER_LONG == 32 &&
1033		    decoder->len < INTEL_PT_PKT_MAX_SZ && !decoder->next_buf) {
1034			ret = intel_pt_get_split_packet(decoder);
1035			if (ret < 0)
1036				return ret;
1037		}
1038		if (ret <= 0)
1039			return intel_pt_bad_packet(decoder);
1040
1041		decoder->pkt_len = ret;
1042		decoder->pkt_step = ret;
1043		intel_pt_decoder_log_packet(decoder);
1044	} while (decoder->packet.type == INTEL_PT_PAD);
1045
1046	return 0;
1047}
1048
1049static uint64_t intel_pt_next_period(struct intel_pt_decoder *decoder)
1050{
1051	uint64_t timestamp, masked_timestamp;
1052
1053	timestamp = decoder->timestamp + decoder->timestamp_insn_cnt;
1054	masked_timestamp = timestamp & decoder->period_mask;
1055	if (decoder->continuous_period) {
1056		if (masked_timestamp > decoder->last_masked_timestamp)
1057			return 1;
1058	} else {
1059		timestamp += 1;
1060		masked_timestamp = timestamp & decoder->period_mask;
1061		if (masked_timestamp > decoder->last_masked_timestamp) {
1062			decoder->last_masked_timestamp = masked_timestamp;
1063			decoder->continuous_period = true;
1064		}
1065	}
1066
1067	if (masked_timestamp < decoder->last_masked_timestamp)
1068		return decoder->period_ticks;
1069
1070	return decoder->period_ticks - (timestamp - masked_timestamp);
1071}
1072
1073static uint64_t intel_pt_next_sample(struct intel_pt_decoder *decoder)
1074{
1075	switch (decoder->period_type) {
1076	case INTEL_PT_PERIOD_INSTRUCTIONS:
1077		return decoder->period - decoder->period_insn_cnt;
1078	case INTEL_PT_PERIOD_TICKS:
1079		return intel_pt_next_period(decoder);
1080	case INTEL_PT_PERIOD_NONE:
1081	case INTEL_PT_PERIOD_MTC:
1082	default:
1083		return 0;
1084	}
1085}
1086
1087static void intel_pt_sample_insn(struct intel_pt_decoder *decoder)
1088{
1089	uint64_t timestamp, masked_timestamp;
1090
1091	switch (decoder->period_type) {
1092	case INTEL_PT_PERIOD_INSTRUCTIONS:
1093		decoder->period_insn_cnt = 0;
1094		break;
1095	case INTEL_PT_PERIOD_TICKS:
1096		timestamp = decoder->timestamp + decoder->timestamp_insn_cnt;
1097		masked_timestamp = timestamp & decoder->period_mask;
1098		if (masked_timestamp > decoder->last_masked_timestamp)
1099			decoder->last_masked_timestamp = masked_timestamp;
1100		else
1101			decoder->last_masked_timestamp += decoder->period_ticks;
1102		break;
1103	case INTEL_PT_PERIOD_NONE:
1104	case INTEL_PT_PERIOD_MTC:
1105	default:
1106		break;
1107	}
1108
1109	decoder->state.type |= INTEL_PT_INSTRUCTION;
1110}
1111
1112/*
1113 * Sample FUP instruction at the same time as reporting the FUP event, so the
1114 * instruction sample gets the same flags as the FUP event.
1115 */
1116static void intel_pt_sample_fup_insn(struct intel_pt_decoder *decoder)
1117{
1118	struct intel_pt_insn intel_pt_insn;
1119	uint64_t max_insn_cnt, insn_cnt = 0;
1120	int err;
1121
1122	decoder->state.insn_op = INTEL_PT_OP_OTHER;
1123	decoder->state.insn_len = 0;
1124
1125	if (!decoder->branch_enable || !decoder->pge || decoder->hop ||
1126	    decoder->ip != decoder->last_ip)
1127		return;
1128
1129	if (!decoder->mtc_insn)
1130		decoder->mtc_insn = true;
1131
1132	max_insn_cnt = intel_pt_next_sample(decoder);
1133	if (max_insn_cnt != 1)
1134		return;
1135
1136	err = decoder->walk_insn(&intel_pt_insn, &insn_cnt, &decoder->ip,
1137				 0, max_insn_cnt, decoder->data);
1138	/* Ignore error, it will be reported next walk anyway */
1139	if (err)
1140		return;
1141
1142	if (intel_pt_insn.branch != INTEL_PT_BR_NO_BRANCH) {
1143		intel_pt_log_at("ERROR: Unexpected branch at FUP instruction", decoder->ip);
1144		return;
1145	}
1146
1147	decoder->tot_insn_cnt += insn_cnt;
1148	decoder->timestamp_insn_cnt += insn_cnt;
1149	decoder->sample_insn_cnt += insn_cnt;
1150	decoder->period_insn_cnt += insn_cnt;
1151
1152	intel_pt_sample_insn(decoder);
1153
1154	decoder->state.type |= INTEL_PT_INSTRUCTION;
1155	decoder->ip += intel_pt_insn.length;
1156}
1157
1158static int intel_pt_walk_insn(struct intel_pt_decoder *decoder,
1159			      struct intel_pt_insn *intel_pt_insn, uint64_t ip)
1160{
1161	uint64_t max_insn_cnt, insn_cnt = 0;
1162	int err;
1163
1164	if (!decoder->mtc_insn)
1165		decoder->mtc_insn = true;
1166
1167	max_insn_cnt = intel_pt_next_sample(decoder);
1168
1169	err = decoder->walk_insn(intel_pt_insn, &insn_cnt, &decoder->ip, ip,
1170				 max_insn_cnt, decoder->data);
1171
1172	decoder->tot_insn_cnt += insn_cnt;
1173	decoder->timestamp_insn_cnt += insn_cnt;
1174	decoder->sample_insn_cnt += insn_cnt;
1175	decoder->period_insn_cnt += insn_cnt;
1176
1177	if (err) {
1178		decoder->no_progress = 0;
1179		decoder->pkt_state = INTEL_PT_STATE_ERR2;
1180		intel_pt_log_at("ERROR: Failed to get instruction",
1181				decoder->ip);
1182		if (err == -ENOENT)
1183			return -ENOLINK;
1184		return -EILSEQ;
1185	}
1186
1187	if (ip && decoder->ip == ip) {
1188		err = -EAGAIN;
1189		goto out;
1190	}
1191
1192	if (max_insn_cnt && insn_cnt >= max_insn_cnt)
1193		intel_pt_sample_insn(decoder);
1194
1195	if (intel_pt_insn->branch == INTEL_PT_BR_NO_BRANCH) {
1196		decoder->state.type = INTEL_PT_INSTRUCTION;
1197		decoder->state.from_ip = decoder->ip;
1198		decoder->state.to_ip = 0;
1199		decoder->ip += intel_pt_insn->length;
1200		err = INTEL_PT_RETURN;
1201		goto out;
1202	}
1203
1204	if (intel_pt_insn->op == INTEL_PT_OP_CALL) {
1205		/* Zero-length calls are excluded */
1206		if (intel_pt_insn->branch != INTEL_PT_BR_UNCONDITIONAL ||
1207		    intel_pt_insn->rel) {
1208			err = intel_pt_push(&decoder->stack, decoder->ip +
1209					    intel_pt_insn->length);
1210			if (err)
1211				goto out;
1212		}
1213	} else if (intel_pt_insn->op == INTEL_PT_OP_RET) {
1214		decoder->ret_addr = intel_pt_pop(&decoder->stack);
1215	}
1216
1217	if (intel_pt_insn->branch == INTEL_PT_BR_UNCONDITIONAL) {
1218		int cnt = decoder->no_progress++;
1219
1220		decoder->state.from_ip = decoder->ip;
1221		decoder->ip += intel_pt_insn->length +
1222				intel_pt_insn->rel;
1223		decoder->state.to_ip = decoder->ip;
1224		err = INTEL_PT_RETURN;
1225
1226		/*
1227		 * Check for being stuck in a loop.  This can happen if a
1228		 * decoder error results in the decoder erroneously setting the
1229		 * ip to an address that is itself in an infinite loop that
1230		 * consumes no packets.  When that happens, there must be an
1231		 * unconditional branch.
1232		 */
1233		if (cnt) {
1234			if (cnt == 1) {
1235				decoder->stuck_ip = decoder->state.to_ip;
1236				decoder->stuck_ip_prd = 1;
1237				decoder->stuck_ip_cnt = 1;
1238			} else if (cnt > decoder->max_loops ||
1239				   decoder->state.to_ip == decoder->stuck_ip) {
1240				intel_pt_log_at("ERROR: Never-ending loop",
1241						decoder->state.to_ip);
1242				decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1243				err = -ELOOP;
1244				goto out;
1245			} else if (!--decoder->stuck_ip_cnt) {
1246				decoder->stuck_ip_prd += 1;
1247				decoder->stuck_ip_cnt = decoder->stuck_ip_prd;
1248				decoder->stuck_ip = decoder->state.to_ip;
1249			}
1250		}
1251		goto out_no_progress;
1252	}
1253out:
1254	decoder->no_progress = 0;
1255out_no_progress:
1256	decoder->state.insn_op = intel_pt_insn->op;
1257	decoder->state.insn_len = intel_pt_insn->length;
1258	memcpy(decoder->state.insn, intel_pt_insn->buf,
1259	       INTEL_PT_INSN_BUF_SZ);
1260
1261	if (decoder->tx_flags & INTEL_PT_IN_TX)
1262		decoder->state.flags |= INTEL_PT_IN_TX;
1263
1264	return err;
1265}
1266
1267static void intel_pt_mode_exec_status(struct intel_pt_decoder *decoder)
1268{
1269	bool iflag = decoder->packet.count & INTEL_PT_IFLAG;
1270
1271	decoder->exec_mode = decoder->packet.payload;
1272	decoder->iflag = iflag;
1273	decoder->next_iflag = iflag;
1274	decoder->state.from_iflag = iflag;
1275	decoder->state.to_iflag = iflag;
1276}
1277
1278static void intel_pt_mode_exec(struct intel_pt_decoder *decoder)
1279{
1280	bool iflag = decoder->packet.count & INTEL_PT_IFLAG;
1281
1282	decoder->exec_mode = decoder->packet.payload;
1283	decoder->next_iflag = iflag;
1284}
1285
1286static void intel_pt_sample_iflag(struct intel_pt_decoder *decoder)
1287{
1288	decoder->state.type |= INTEL_PT_IFLAG_CHG;
1289	decoder->state.from_iflag = decoder->iflag;
1290	decoder->state.to_iflag = decoder->next_iflag;
1291	decoder->iflag = decoder->next_iflag;
1292}
1293
1294static void intel_pt_sample_iflag_chg(struct intel_pt_decoder *decoder)
1295{
1296	if (decoder->iflag != decoder->next_iflag)
1297		intel_pt_sample_iflag(decoder);
1298}
1299
1300static void intel_pt_clear_fup_event(struct intel_pt_decoder *decoder)
1301{
1302	decoder->set_fup_tx_flags = false;
1303	decoder->set_fup_ptw = false;
1304	decoder->set_fup_mwait = false;
1305	decoder->set_fup_pwre = false;
1306	decoder->set_fup_exstop = false;
1307	decoder->set_fup_bep = false;
1308	decoder->set_fup_cfe_ip = false;
1309	decoder->set_fup_cfe = false;
1310	decoder->evd_cnt = 0;
1311	decoder->set_fup_mode_exec = false;
1312	decoder->iflag = decoder->next_iflag;
1313}
1314
1315static bool intel_pt_fup_event(struct intel_pt_decoder *decoder, bool no_tip)
1316{
1317	enum intel_pt_sample_type type = decoder->state.type;
1318	bool sample_fup_insn = false;
1319	bool ret = false;
1320
1321	decoder->state.type &= ~INTEL_PT_BRANCH;
1322
1323	if (decoder->set_fup_cfe_ip || decoder->set_fup_cfe) {
1324		bool ip = decoder->set_fup_cfe_ip;
1325
1326		decoder->set_fup_cfe_ip = false;
1327		decoder->set_fup_cfe = false;
1328		decoder->state.type |= INTEL_PT_EVT;
1329		if (!ip && decoder->pge)
1330			decoder->state.type |= INTEL_PT_BRANCH;
1331		decoder->state.cfe_type = decoder->fup_cfe_pkt.count;
1332		decoder->state.cfe_vector = decoder->fup_cfe_pkt.payload;
1333		decoder->state.evd_cnt = decoder->evd_cnt;
1334		decoder->state.evd = decoder->evd;
1335		decoder->evd_cnt = 0;
1336		if (ip || decoder->pge)
1337			decoder->state.flags |= INTEL_PT_FUP_IP;
1338		ret = true;
1339	}
1340	if (decoder->set_fup_mode_exec) {
1341		decoder->set_fup_mode_exec = false;
1342		intel_pt_sample_iflag(decoder);
1343		sample_fup_insn = no_tip;
1344		ret = true;
1345	}
1346	if (decoder->set_fup_tx_flags) {
1347		decoder->set_fup_tx_flags = false;
1348		decoder->tx_flags = decoder->fup_tx_flags;
1349		decoder->state.type |= INTEL_PT_TRANSACTION;
1350		if (decoder->fup_tx_flags & INTEL_PT_ABORT_TX)
1351			decoder->state.type |= INTEL_PT_BRANCH;
1352		decoder->state.flags = decoder->fup_tx_flags;
1353		ret = true;
1354	}
1355	if (decoder->set_fup_ptw) {
1356		decoder->set_fup_ptw = false;
1357		decoder->state.type |= INTEL_PT_PTW;
1358		decoder->state.flags |= INTEL_PT_FUP_IP;
 
 
1359		decoder->state.ptw_payload = decoder->fup_ptw_payload;
1360		ret = true;
1361	}
1362	if (decoder->set_fup_mwait) {
1363		decoder->set_fup_mwait = false;
1364		decoder->state.type |= INTEL_PT_MWAIT_OP;
 
 
1365		decoder->state.mwait_payload = decoder->fup_mwait_payload;
1366		ret = true;
1367	}
1368	if (decoder->set_fup_pwre) {
1369		decoder->set_fup_pwre = false;
1370		decoder->state.type |= INTEL_PT_PWR_ENTRY;
 
 
 
1371		decoder->state.pwre_payload = decoder->fup_pwre_payload;
1372		ret = true;
1373	}
1374	if (decoder->set_fup_exstop) {
1375		decoder->set_fup_exstop = false;
1376		decoder->state.type |= INTEL_PT_EX_STOP;
 
1377		decoder->state.flags |= INTEL_PT_FUP_IP;
 
 
1378		ret = true;
1379	}
1380	if (decoder->set_fup_bep) {
1381		decoder->set_fup_bep = false;
1382		decoder->state.type |= INTEL_PT_BLK_ITEMS;
1383		ret = true;
1384	}
1385	if (decoder->overflow) {
1386		decoder->overflow = false;
1387		if (!ret && !decoder->pge) {
1388			if (decoder->hop) {
1389				decoder->state.type = 0;
1390				decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
1391			}
1392			decoder->pge = true;
1393			decoder->state.type |= INTEL_PT_BRANCH | INTEL_PT_TRACE_BEGIN;
1394			decoder->state.from_ip = 0;
1395			decoder->state.to_ip = decoder->ip;
1396			return true;
1397		}
1398	}
1399	if (ret) {
1400		decoder->state.from_ip = decoder->ip;
1401		decoder->state.to_ip = 0;
1402		if (sample_fup_insn)
1403			intel_pt_sample_fup_insn(decoder);
1404	} else {
1405		decoder->state.type = type;
1406	}
1407	return ret;
1408}
1409
1410static inline bool intel_pt_fup_with_nlip(struct intel_pt_decoder *decoder,
1411					  struct intel_pt_insn *intel_pt_insn,
1412					  uint64_t ip, int err)
1413{
1414	return decoder->flags & INTEL_PT_FUP_WITH_NLIP && !err &&
1415	       intel_pt_insn->branch == INTEL_PT_BR_INDIRECT &&
1416	       ip == decoder->ip + intel_pt_insn->length;
1417}
1418
1419static int intel_pt_walk_fup(struct intel_pt_decoder *decoder)
1420{
1421	struct intel_pt_insn intel_pt_insn;
1422	uint64_t ip;
1423	int err;
1424
1425	ip = decoder->last_ip;
1426
1427	while (1) {
1428		err = intel_pt_walk_insn(decoder, &intel_pt_insn, ip);
1429		if (err == INTEL_PT_RETURN)
1430			return 0;
1431		if (err == -EAGAIN ||
1432		    intel_pt_fup_with_nlip(decoder, &intel_pt_insn, ip, err)) {
1433			bool no_tip = decoder->pkt_state != INTEL_PT_STATE_FUP;
1434
1435			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1436			if (intel_pt_fup_event(decoder, no_tip) && no_tip)
1437				return 0;
1438			return -EAGAIN;
1439		}
1440		decoder->set_fup_tx_flags = false;
1441		if (err)
1442			return err;
1443
1444		if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1445			intel_pt_log_at("ERROR: Unexpected indirect branch",
1446					decoder->ip);
1447			decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1448			return -ENOENT;
1449		}
1450
1451		if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1452			intel_pt_log_at("ERROR: Unexpected conditional branch",
1453					decoder->ip);
1454			decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1455			return -ENOENT;
1456		}
1457
1458		intel_pt_bug(decoder);
1459	}
1460}
1461
1462static int intel_pt_walk_tip(struct intel_pt_decoder *decoder)
1463{
1464	struct intel_pt_insn intel_pt_insn;
1465	int err;
1466
1467	err = intel_pt_walk_insn(decoder, &intel_pt_insn, 0);
1468	if (err == INTEL_PT_RETURN &&
1469	    decoder->pgd_ip &&
1470	    decoder->pkt_state == INTEL_PT_STATE_TIP_PGD &&
1471	    (decoder->state.type & INTEL_PT_BRANCH) &&
1472	    decoder->pgd_ip(decoder->state.to_ip, decoder->data)) {
1473		/* Unconditional branch leaving filter region */
1474		decoder->no_progress = 0;
1475		decoder->pge = false;
1476		decoder->continuous_period = false;
1477		decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1478		decoder->state.type |= INTEL_PT_TRACE_END;
1479		intel_pt_update_nr(decoder);
1480		return 0;
1481	}
1482	if (err == INTEL_PT_RETURN)
1483		return 0;
1484	if (err)
1485		return err;
1486
1487	intel_pt_update_nr(decoder);
1488	intel_pt_sample_iflag_chg(decoder);
1489
1490	if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1491		if (decoder->pkt_state == INTEL_PT_STATE_TIP_PGD) {
1492			decoder->pge = false;
1493			decoder->continuous_period = false;
1494			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1495			decoder->state.from_ip = decoder->ip;
1496			if (decoder->packet.count == 0) {
1497				decoder->state.to_ip = 0;
1498			} else {
1499				decoder->state.to_ip = decoder->last_ip;
1500				decoder->ip = decoder->last_ip;
1501			}
1502			decoder->state.type |= INTEL_PT_TRACE_END;
1503		} else {
1504			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1505			decoder->state.from_ip = decoder->ip;
1506			if (decoder->packet.count == 0) {
1507				decoder->state.to_ip = 0;
1508			} else {
1509				decoder->state.to_ip = decoder->last_ip;
1510				decoder->ip = decoder->last_ip;
1511			}
1512		}
1513		return 0;
1514	}
1515
1516	if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1517		uint64_t to_ip = decoder->ip + intel_pt_insn.length +
1518				 intel_pt_insn.rel;
1519
1520		if (decoder->pgd_ip &&
1521		    decoder->pkt_state == INTEL_PT_STATE_TIP_PGD &&
1522		    decoder->pgd_ip(to_ip, decoder->data)) {
1523			/* Conditional branch leaving filter region */
1524			decoder->pge = false;
1525			decoder->continuous_period = false;
1526			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1527			decoder->ip = to_ip;
1528			decoder->state.from_ip = decoder->ip;
1529			decoder->state.to_ip = to_ip;
1530			decoder->state.type |= INTEL_PT_TRACE_END;
1531			return 0;
1532		}
1533		intel_pt_log_at("ERROR: Conditional branch when expecting indirect branch",
1534				decoder->ip);
1535		decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1536		return -ENOENT;
1537	}
1538
1539	return intel_pt_bug(decoder);
1540}
1541
1542struct eptw_data {
1543	int bit_countdown;
1544	uint64_t payload;
1545};
1546
1547static int intel_pt_eptw_lookahead_cb(struct intel_pt_pkt_info *pkt_info)
1548{
1549	struct eptw_data *data = pkt_info->data;
1550	int nr_bits;
1551
1552	switch (pkt_info->packet.type) {
1553	case INTEL_PT_PAD:
1554	case INTEL_PT_MNT:
1555	case INTEL_PT_MODE_EXEC:
1556	case INTEL_PT_MODE_TSX:
1557	case INTEL_PT_MTC:
1558	case INTEL_PT_FUP:
1559	case INTEL_PT_CYC:
1560	case INTEL_PT_CBR:
1561	case INTEL_PT_TSC:
1562	case INTEL_PT_TMA:
1563	case INTEL_PT_PIP:
1564	case INTEL_PT_VMCS:
1565	case INTEL_PT_PSB:
1566	case INTEL_PT_PSBEND:
1567	case INTEL_PT_PTWRITE:
1568	case INTEL_PT_PTWRITE_IP:
1569	case INTEL_PT_EXSTOP:
1570	case INTEL_PT_EXSTOP_IP:
1571	case INTEL_PT_MWAIT:
1572	case INTEL_PT_PWRE:
1573	case INTEL_PT_PWRX:
1574	case INTEL_PT_BBP:
1575	case INTEL_PT_BIP:
1576	case INTEL_PT_BEP:
1577	case INTEL_PT_BEP_IP:
1578	case INTEL_PT_CFE:
1579	case INTEL_PT_CFE_IP:
1580	case INTEL_PT_EVD:
1581		break;
1582
1583	case INTEL_PT_TNT:
1584		nr_bits = data->bit_countdown;
1585		if (nr_bits > pkt_info->packet.count)
1586			nr_bits = pkt_info->packet.count;
1587		data->payload <<= nr_bits;
1588		data->payload |= pkt_info->packet.payload >> (64 - nr_bits);
1589		data->bit_countdown -= nr_bits;
1590		return !data->bit_countdown;
1591
1592	case INTEL_PT_TIP_PGE:
1593	case INTEL_PT_TIP_PGD:
1594	case INTEL_PT_TIP:
1595	case INTEL_PT_BAD:
1596	case INTEL_PT_OVF:
1597	case INTEL_PT_TRACESTOP:
1598	default:
1599		return 1;
1600	}
1601
1602	return 0;
1603}
1604
1605static int intel_pt_emulated_ptwrite(struct intel_pt_decoder *decoder)
1606{
1607	int n = 64 - decoder->tnt.count;
1608	struct eptw_data data = {
1609		.bit_countdown = n,
1610		.payload = decoder->tnt.payload >> n,
1611	};
1612
1613	decoder->emulated_ptwrite = false;
1614	intel_pt_log("Emulated ptwrite detected\n");
1615
1616	intel_pt_pkt_lookahead(decoder, intel_pt_eptw_lookahead_cb, &data);
1617	if (data.bit_countdown)
1618		return -ECONNRESET;
1619
1620	decoder->state.type = INTEL_PT_PTW;
1621	decoder->state.from_ip = decoder->ip;
1622	decoder->state.to_ip = 0;
1623	decoder->state.ptw_payload = data.payload;
1624	return 0;
1625}
1626
1627static int intel_pt_walk_tnt(struct intel_pt_decoder *decoder)
1628{
1629	struct intel_pt_insn intel_pt_insn;
1630	int err;
1631
1632	while (1) {
1633		if (decoder->emulated_ptwrite)
1634			return intel_pt_emulated_ptwrite(decoder);
1635		err = intel_pt_walk_insn(decoder, &intel_pt_insn, 0);
1636		if (err == INTEL_PT_RETURN) {
1637			decoder->emulated_ptwrite = intel_pt_insn.emulated_ptwrite;
1638			return 0;
1639		}
1640		if (err) {
1641			decoder->emulated_ptwrite = false;
1642			return err;
1643		}
1644
1645		if (intel_pt_insn.op == INTEL_PT_OP_RET) {
1646			if (!decoder->return_compression) {
1647				intel_pt_log_at("ERROR: RET when expecting conditional branch",
1648						decoder->ip);
1649				decoder->pkt_state = INTEL_PT_STATE_ERR3;
1650				return -ENOENT;
1651			}
1652			if (!decoder->ret_addr) {
1653				intel_pt_log_at("ERROR: Bad RET compression (stack empty)",
1654						decoder->ip);
1655				decoder->pkt_state = INTEL_PT_STATE_ERR3;
1656				return -ENOENT;
1657			}
1658			if (!(decoder->tnt.payload & BIT63)) {
1659				intel_pt_log_at("ERROR: Bad RET compression (TNT=N)",
1660						decoder->ip);
1661				decoder->pkt_state = INTEL_PT_STATE_ERR3;
1662				return -ENOENT;
1663			}
1664			decoder->tnt.count -= 1;
1665			if (decoder->tnt.count)
1666				decoder->pkt_state = INTEL_PT_STATE_TNT_CONT;
1667			else
1668				decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1669			decoder->tnt.payload <<= 1;
1670			decoder->state.from_ip = decoder->ip;
1671			decoder->ip = decoder->ret_addr;
1672			decoder->state.to_ip = decoder->ip;
1673			return 0;
1674		}
1675
1676		if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1677			/* Handle deferred TIPs */
1678			err = intel_pt_get_next_packet(decoder);
1679			if (err)
1680				return err;
1681			if (decoder->packet.type != INTEL_PT_TIP ||
1682			    decoder->packet.count == 0) {
1683				intel_pt_log_at("ERROR: Missing deferred TIP for indirect branch",
1684						decoder->ip);
1685				decoder->pkt_state = INTEL_PT_STATE_ERR3;
1686				decoder->pkt_step = 0;
1687				return -ENOENT;
1688			}
1689			intel_pt_set_last_ip(decoder);
1690			decoder->state.from_ip = decoder->ip;
1691			decoder->state.to_ip = decoder->last_ip;
1692			decoder->ip = decoder->last_ip;
1693			intel_pt_update_nr(decoder);
1694			intel_pt_sample_iflag_chg(decoder);
1695			return 0;
1696		}
1697
1698		if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1699			decoder->tnt.count -= 1;
1700			if (decoder->tnt.count)
1701				decoder->pkt_state = INTEL_PT_STATE_TNT_CONT;
1702			else
1703				decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1704			if (decoder->tnt.payload & BIT63) {
1705				decoder->tnt.payload <<= 1;
1706				decoder->state.from_ip = decoder->ip;
1707				decoder->ip += intel_pt_insn.length +
1708					       intel_pt_insn.rel;
1709				decoder->state.to_ip = decoder->ip;
1710				return 0;
1711			}
1712			/* Instruction sample for a non-taken branch */
1713			if (decoder->state.type & INTEL_PT_INSTRUCTION) {
1714				decoder->tnt.payload <<= 1;
1715				decoder->state.type = INTEL_PT_INSTRUCTION;
1716				decoder->state.from_ip = decoder->ip;
1717				decoder->state.to_ip = 0;
1718				decoder->ip += intel_pt_insn.length;
1719				return 0;
1720			}
1721			decoder->sample_cyc = false;
1722			decoder->ip += intel_pt_insn.length;
1723			if (!decoder->tnt.count) {
1724				intel_pt_update_sample_time(decoder);
1725				return -EAGAIN;
1726			}
1727			decoder->tnt.payload <<= 1;
1728			continue;
1729		}
1730
1731		return intel_pt_bug(decoder);
1732	}
1733}
1734
1735static int intel_pt_mode_tsx(struct intel_pt_decoder *decoder, bool *no_tip)
1736{
1737	unsigned int fup_tx_flags;
1738	int err;
1739
1740	fup_tx_flags = decoder->packet.payload &
1741		       (INTEL_PT_IN_TX | INTEL_PT_ABORT_TX);
1742	err = intel_pt_get_next_packet(decoder);
1743	if (err)
1744		return err;
1745	if (decoder->packet.type == INTEL_PT_FUP) {
1746		decoder->fup_tx_flags = fup_tx_flags;
1747		decoder->set_fup_tx_flags = true;
1748		if (!(decoder->fup_tx_flags & INTEL_PT_ABORT_TX))
1749			*no_tip = true;
1750	} else {
1751		intel_pt_log_at("ERROR: Missing FUP after MODE.TSX",
1752				decoder->pos);
1753		intel_pt_update_in_tx(decoder);
1754	}
1755	return 0;
1756}
1757
1758static int intel_pt_evd(struct intel_pt_decoder *decoder)
1759{
1760	if (decoder->evd_cnt >= INTEL_PT_MAX_EVDS) {
1761		intel_pt_log_at("ERROR: Too many EVD packets", decoder->pos);
1762		return -ENOSYS;
1763	}
1764	decoder->evd[decoder->evd_cnt++] = (struct intel_pt_evd){
1765		.type = decoder->packet.count,
1766		.payload = decoder->packet.payload,
1767	};
1768	return 0;
1769}
1770
1771static uint64_t intel_pt_8b_tsc(uint64_t timestamp, uint64_t ref_timestamp)
1772{
1773	timestamp |= (ref_timestamp & (0xffULL << 56));
1774
1775	if (timestamp < ref_timestamp) {
1776		if (ref_timestamp - timestamp > (1ULL << 55))
1777			timestamp += (1ULL << 56);
1778	} else {
1779		if (timestamp - ref_timestamp > (1ULL << 55))
1780			timestamp -= (1ULL << 56);
1781	}
1782
1783	return timestamp;
1784}
1785
1786/* For use only when decoder->vm_time_correlation is true */
1787static bool intel_pt_time_in_range(struct intel_pt_decoder *decoder,
1788				   uint64_t timestamp)
1789{
1790	uint64_t max_timestamp = decoder->buf_timestamp;
1791
1792	if (!max_timestamp) {
1793		max_timestamp = decoder->last_reliable_timestamp +
1794				0x400000000ULL;
1795	}
1796	return timestamp >= decoder->last_reliable_timestamp &&
1797	       timestamp < decoder->buf_timestamp;
1798}
1799
1800static void intel_pt_calc_tsc_timestamp(struct intel_pt_decoder *decoder)
1801{
1802	uint64_t timestamp;
1803	bool bad = false;
1804
1805	decoder->have_tma = false;
1806
1807	if (decoder->ref_timestamp) {
1808		timestamp = intel_pt_8b_tsc(decoder->packet.payload,
1809					    decoder->ref_timestamp);
1810		decoder->tsc_timestamp = timestamp;
1811		decoder->timestamp = timestamp;
1812		decoder->ref_timestamp = 0;
1813		decoder->timestamp_insn_cnt = 0;
1814	} else if (decoder->timestamp) {
1815		timestamp = decoder->packet.payload |
1816			    (decoder->timestamp & (0xffULL << 56));
1817		decoder->tsc_timestamp = timestamp;
1818		if (timestamp < decoder->timestamp &&
1819		    decoder->timestamp - timestamp < decoder->tsc_slip) {
1820			intel_pt_log_to("Suppressing backwards timestamp",
1821					timestamp);
1822			timestamp = decoder->timestamp;
1823		}
1824		if (timestamp < decoder->timestamp) {
1825			if (!decoder->buf_timestamp ||
1826			    (timestamp + (1ULL << 56) < decoder->buf_timestamp)) {
1827				intel_pt_log_to("Wraparound timestamp", timestamp);
1828				timestamp += (1ULL << 56);
1829				decoder->tsc_timestamp = timestamp;
1830			} else {
1831				intel_pt_log_to("Suppressing bad timestamp", timestamp);
1832				timestamp = decoder->timestamp;
1833				bad = true;
1834			}
1835		}
1836		if (decoder->vm_time_correlation &&
1837		    (bad || !intel_pt_time_in_range(decoder, timestamp)) &&
1838		    intel_pt_print_once(decoder, INTEL_PT_PRT_ONCE_ERANGE))
1839			p_log("Timestamp out of range");
1840		decoder->timestamp = timestamp;
1841		decoder->timestamp_insn_cnt = 0;
1842	}
1843
1844	if (decoder->last_packet_type == INTEL_PT_CYC) {
1845		decoder->cyc_ref_timestamp = decoder->timestamp;
1846		decoder->cycle_cnt = 0;
1847		decoder->have_calc_cyc_to_tsc = false;
1848		intel_pt_calc_cyc_to_tsc(decoder, false);
1849	}
1850
1851	intel_pt_log_to("Setting timestamp", decoder->timestamp);
1852}
1853
1854static int intel_pt_overflow(struct intel_pt_decoder *decoder)
1855{
1856	intel_pt_log("ERROR: Buffer overflow\n");
1857	intel_pt_clear_tx_flags(decoder);
1858	intel_pt_set_nr(decoder);
1859	decoder->timestamp_insn_cnt = 0;
1860	decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1861	decoder->state.from_ip = decoder->ip;
1862	decoder->ip = 0;
1863	decoder->pge = false;
1864	intel_pt_clear_fup_event(decoder);
1865	decoder->overflow = true;
1866	return -EOVERFLOW;
1867}
1868
1869static inline void intel_pt_mtc_cyc_cnt_pge(struct intel_pt_decoder *decoder)
1870{
1871	if (decoder->have_cyc)
1872		return;
1873
1874	decoder->cyc_cnt_timestamp = decoder->timestamp;
1875	decoder->base_cyc_cnt = decoder->tot_cyc_cnt;
1876}
1877
1878static inline void intel_pt_mtc_cyc_cnt_cbr(struct intel_pt_decoder *decoder)
1879{
1880	decoder->tsc_to_cyc = decoder->cbr / decoder->max_non_turbo_ratio_fp;
1881
1882	if (decoder->pge)
1883		intel_pt_mtc_cyc_cnt_pge(decoder);
1884}
1885
1886static inline void intel_pt_mtc_cyc_cnt_upd(struct intel_pt_decoder *decoder)
1887{
1888	uint64_t tot_cyc_cnt, tsc_delta;
1889
1890	if (decoder->have_cyc)
1891		return;
1892
1893	decoder->sample_cyc = true;
1894
1895	if (!decoder->pge || decoder->timestamp <= decoder->cyc_cnt_timestamp)
1896		return;
1897
1898	tsc_delta = decoder->timestamp - decoder->cyc_cnt_timestamp;
1899	tot_cyc_cnt = tsc_delta * decoder->tsc_to_cyc + decoder->base_cyc_cnt;
1900
1901	if (tot_cyc_cnt > decoder->tot_cyc_cnt)
1902		decoder->tot_cyc_cnt = tot_cyc_cnt;
1903}
1904
1905static void intel_pt_calc_tma(struct intel_pt_decoder *decoder)
1906{
1907	uint32_t ctc = decoder->packet.payload;
1908	uint32_t fc = decoder->packet.count;
1909	uint32_t ctc_rem = ctc & decoder->ctc_rem_mask;
1910
1911	if (!decoder->tsc_ctc_ratio_d)
1912		return;
1913
1914	if (decoder->pge && !decoder->in_psb)
1915		intel_pt_mtc_cyc_cnt_pge(decoder);
1916	else
1917		intel_pt_mtc_cyc_cnt_upd(decoder);
1918
1919	decoder->last_mtc = (ctc >> decoder->mtc_shift) & 0xff;
1920	decoder->last_ctc = ctc - ctc_rem;
1921	decoder->ctc_timestamp = decoder->tsc_timestamp - fc;
1922	if (decoder->tsc_ctc_mult) {
1923		decoder->ctc_timestamp -= ctc_rem * decoder->tsc_ctc_mult;
1924	} else {
1925		decoder->ctc_timestamp -= multdiv(ctc_rem,
1926						  decoder->tsc_ctc_ratio_n,
1927						  decoder->tsc_ctc_ratio_d);
1928	}
1929	decoder->ctc_delta = 0;
1930	decoder->have_tma = true;
1931	decoder->fixup_last_mtc = true;
1932	intel_pt_log("CTC timestamp " x64_fmt " last MTC %#x  CTC rem %#x\n",
1933		     decoder->ctc_timestamp, decoder->last_mtc, ctc_rem);
1934}
1935
1936static void intel_pt_calc_mtc_timestamp(struct intel_pt_decoder *decoder)
1937{
1938	uint64_t timestamp;
1939	uint32_t mtc, mtc_delta;
1940
1941	if (!decoder->have_tma)
1942		return;
1943
1944	mtc = decoder->packet.payload;
1945
1946	if (decoder->mtc_shift > 8 && decoder->fixup_last_mtc) {
1947		decoder->fixup_last_mtc = false;
1948		intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
1949					&decoder->last_mtc);
1950	}
1951
1952	if (mtc > decoder->last_mtc)
1953		mtc_delta = mtc - decoder->last_mtc;
1954	else
1955		mtc_delta = mtc + 256 - decoder->last_mtc;
1956
1957	decoder->ctc_delta += mtc_delta << decoder->mtc_shift;
1958
1959	if (decoder->tsc_ctc_mult) {
1960		timestamp = decoder->ctc_timestamp +
1961			    decoder->ctc_delta * decoder->tsc_ctc_mult;
1962	} else {
1963		timestamp = decoder->ctc_timestamp +
1964			    multdiv(decoder->ctc_delta,
1965				    decoder->tsc_ctc_ratio_n,
1966				    decoder->tsc_ctc_ratio_d);
1967	}
1968
1969	if (timestamp < decoder->timestamp)
1970		intel_pt_log("Suppressing MTC timestamp " x64_fmt " less than current timestamp " x64_fmt "\n",
1971			     timestamp, decoder->timestamp);
1972	else
1973		decoder->timestamp = timestamp;
1974
1975	intel_pt_mtc_cyc_cnt_upd(decoder);
1976
1977	decoder->timestamp_insn_cnt = 0;
1978	decoder->last_mtc = mtc;
1979
1980	if (decoder->last_packet_type == INTEL_PT_CYC) {
1981		decoder->cyc_ref_timestamp = decoder->timestamp;
1982		decoder->cycle_cnt = 0;
1983		decoder->have_calc_cyc_to_tsc = false;
1984		intel_pt_calc_cyc_to_tsc(decoder, true);
1985	}
1986
1987	intel_pt_log_to("Setting timestamp", decoder->timestamp);
1988}
1989
1990static void intel_pt_calc_cbr(struct intel_pt_decoder *decoder)
1991{
1992	unsigned int cbr = decoder->packet.payload & 0xff;
1993
1994	decoder->cbr_payload = decoder->packet.payload;
1995
1996	if (decoder->cbr == cbr)
1997		return;
1998
1999	decoder->cbr = cbr;
2000	decoder->cbr_cyc_to_tsc = decoder->max_non_turbo_ratio_fp / cbr;
2001	decoder->cyc_ref_timestamp = decoder->timestamp;
2002	decoder->cycle_cnt = 0;
2003
2004	intel_pt_mtc_cyc_cnt_cbr(decoder);
2005}
2006
2007static void intel_pt_calc_cyc_timestamp(struct intel_pt_decoder *decoder)
2008{
2009	uint64_t timestamp = decoder->cyc_ref_timestamp;
2010
2011	decoder->have_cyc = true;
2012
2013	decoder->cycle_cnt += decoder->packet.payload;
2014	if (decoder->pge)
2015		decoder->tot_cyc_cnt += decoder->packet.payload;
2016	decoder->sample_cyc = true;
2017
2018	if (!decoder->cyc_ref_timestamp)
2019		return;
2020
2021	if (decoder->have_calc_cyc_to_tsc)
2022		timestamp += decoder->cycle_cnt * decoder->calc_cyc_to_tsc;
2023	else if (decoder->cbr)
2024		timestamp += decoder->cycle_cnt * decoder->cbr_cyc_to_tsc;
2025	else
2026		return;
2027
2028	if (timestamp < decoder->timestamp)
2029		intel_pt_log("Suppressing CYC timestamp " x64_fmt " less than current timestamp " x64_fmt "\n",
2030			     timestamp, decoder->timestamp);
2031	else
2032		decoder->timestamp = timestamp;
2033
2034	decoder->timestamp_insn_cnt = 0;
2035
2036	intel_pt_log_to("Setting timestamp", decoder->timestamp);
2037}
2038
2039static void intel_pt_bbp(struct intel_pt_decoder *decoder)
2040{
2041	if (decoder->prev_pkt_ctx == INTEL_PT_NO_CTX) {
2042		memset(decoder->state.items.mask, 0, sizeof(decoder->state.items.mask));
2043		decoder->state.items.is_32_bit = false;
2044	}
2045	decoder->blk_type = decoder->packet.payload;
2046	decoder->blk_type_pos = intel_pt_blk_type_pos(decoder->blk_type);
2047	if (decoder->blk_type == INTEL_PT_GP_REGS)
2048		decoder->state.items.is_32_bit = decoder->packet.count;
2049	if (decoder->blk_type_pos < 0) {
2050		intel_pt_log("WARNING: Unknown block type %u\n",
2051			     decoder->blk_type);
2052	} else if (decoder->state.items.mask[decoder->blk_type_pos]) {
2053		intel_pt_log("WARNING: Duplicate block type %u\n",
2054			     decoder->blk_type);
2055	}
2056}
2057
2058static void intel_pt_bip(struct intel_pt_decoder *decoder)
2059{
2060	uint32_t id = decoder->packet.count;
2061	uint32_t bit = 1 << id;
2062	int pos = decoder->blk_type_pos;
2063
2064	if (pos < 0 || id >= INTEL_PT_BLK_ITEM_ID_CNT) {
2065		intel_pt_log("WARNING: Unknown block item %u type %d\n",
2066			     id, decoder->blk_type);
2067		return;
2068	}
2069
2070	if (decoder->state.items.mask[pos] & bit) {
2071		intel_pt_log("WARNING: Duplicate block item %u type %d\n",
2072			     id, decoder->blk_type);
2073	}
2074
2075	decoder->state.items.mask[pos] |= bit;
2076	decoder->state.items.val[pos][id] = decoder->packet.payload;
2077}
2078
2079/* Walk PSB+ packets when already in sync. */
2080static int intel_pt_walk_psbend(struct intel_pt_decoder *decoder)
2081{
2082	int err;
2083
2084	decoder->in_psb = true;
2085
2086	while (1) {
2087		err = intel_pt_get_next_packet(decoder);
2088		if (err)
2089			goto out;
2090
2091		switch (decoder->packet.type) {
2092		case INTEL_PT_PSBEND:
2093			err = 0;
2094			goto out;
2095
2096		case INTEL_PT_TIP_PGD:
2097		case INTEL_PT_TIP_PGE:
2098		case INTEL_PT_TIP:
2099		case INTEL_PT_TNT:
2100		case INTEL_PT_TRACESTOP:
2101		case INTEL_PT_BAD:
2102		case INTEL_PT_PSB:
2103		case INTEL_PT_PTWRITE:
2104		case INTEL_PT_PTWRITE_IP:
2105		case INTEL_PT_EXSTOP:
2106		case INTEL_PT_EXSTOP_IP:
2107		case INTEL_PT_MWAIT:
2108		case INTEL_PT_PWRE:
2109		case INTEL_PT_PWRX:
2110		case INTEL_PT_BBP:
2111		case INTEL_PT_BIP:
2112		case INTEL_PT_BEP:
2113		case INTEL_PT_BEP_IP:
2114		case INTEL_PT_CFE:
2115		case INTEL_PT_CFE_IP:
2116		case INTEL_PT_EVD:
2117			decoder->have_tma = false;
2118			intel_pt_log("ERROR: Unexpected packet\n");
2119			err = -EAGAIN;
2120			goto out;
2121
2122		case INTEL_PT_OVF:
2123			err = intel_pt_overflow(decoder);
2124			goto out;
2125
2126		case INTEL_PT_TSC:
2127			intel_pt_calc_tsc_timestamp(decoder);
2128			break;
2129
2130		case INTEL_PT_TMA:
2131			intel_pt_calc_tma(decoder);
2132			break;
2133
2134		case INTEL_PT_CBR:
2135			intel_pt_calc_cbr(decoder);
2136			break;
2137
2138		case INTEL_PT_MODE_EXEC:
2139			intel_pt_mode_exec_status(decoder);
2140			break;
2141
2142		case INTEL_PT_PIP:
2143			intel_pt_set_pip(decoder);
2144			break;
2145
2146		case INTEL_PT_FUP:
2147			decoder->pge = true;
2148			if (decoder->packet.count) {
2149				intel_pt_set_last_ip(decoder);
2150				decoder->psb_ip = decoder->last_ip;
 
 
 
 
2151			}
2152			break;
2153
2154		case INTEL_PT_MODE_TSX:
2155			intel_pt_update_in_tx(decoder);
2156			break;
2157
2158		case INTEL_PT_MTC:
2159			intel_pt_calc_mtc_timestamp(decoder);
2160			if (decoder->period_type == INTEL_PT_PERIOD_MTC)
2161				decoder->state.type |= INTEL_PT_INSTRUCTION;
2162			break;
2163
2164		case INTEL_PT_CYC:
2165			intel_pt_calc_cyc_timestamp(decoder);
2166			break;
2167
2168		case INTEL_PT_VMCS:
2169		case INTEL_PT_MNT:
2170		case INTEL_PT_PAD:
2171		default:
2172			break;
2173		}
2174	}
2175out:
2176	decoder->in_psb = false;
2177
2178	return err;
2179}
2180
2181static int intel_pt_walk_fup_tip(struct intel_pt_decoder *decoder)
2182{
2183	int err;
2184
2185	if (decoder->tx_flags & INTEL_PT_ABORT_TX) {
2186		decoder->tx_flags = 0;
2187		decoder->state.flags &= ~INTEL_PT_IN_TX;
2188		decoder->state.flags |= INTEL_PT_ABORT_TX;
2189	} else {
2190		decoder->state.flags |= INTEL_PT_ASYNC;
2191	}
2192
2193	while (1) {
2194		err = intel_pt_get_next_packet(decoder);
2195		if (err)
2196			return err;
2197
2198		switch (decoder->packet.type) {
2199		case INTEL_PT_TNT:
2200		case INTEL_PT_FUP:
2201		case INTEL_PT_TRACESTOP:
2202		case INTEL_PT_PSB:
2203		case INTEL_PT_TSC:
2204		case INTEL_PT_TMA:
2205		case INTEL_PT_MODE_TSX:
2206		case INTEL_PT_BAD:
2207		case INTEL_PT_PSBEND:
2208		case INTEL_PT_PTWRITE:
2209		case INTEL_PT_PTWRITE_IP:
2210		case INTEL_PT_EXSTOP:
2211		case INTEL_PT_EXSTOP_IP:
2212		case INTEL_PT_MWAIT:
2213		case INTEL_PT_PWRE:
2214		case INTEL_PT_PWRX:
2215		case INTEL_PT_BBP:
2216		case INTEL_PT_BIP:
2217		case INTEL_PT_BEP:
2218		case INTEL_PT_BEP_IP:
2219		case INTEL_PT_CFE:
2220		case INTEL_PT_CFE_IP:
2221		case INTEL_PT_EVD:
2222			intel_pt_log("ERROR: Missing TIP after FUP\n");
2223			decoder->pkt_state = INTEL_PT_STATE_ERR3;
2224			decoder->pkt_step = 0;
2225			return -ENOENT;
2226
2227		case INTEL_PT_CBR:
2228			intel_pt_calc_cbr(decoder);
2229			break;
2230
2231		case INTEL_PT_OVF:
2232			return intel_pt_overflow(decoder);
2233
2234		case INTEL_PT_TIP_PGD:
2235			decoder->state.from_ip = decoder->ip;
2236			if (decoder->packet.count == 0) {
2237				decoder->state.to_ip = 0;
2238			} else {
2239				intel_pt_set_ip(decoder);
2240				decoder->state.to_ip = decoder->ip;
2241			}
2242			decoder->pge = false;
2243			decoder->continuous_period = false;
2244			decoder->state.type |= INTEL_PT_TRACE_END;
2245			intel_pt_update_nr(decoder);
2246			return 0;
2247
2248		case INTEL_PT_TIP_PGE:
2249			decoder->pge = true;
2250			intel_pt_log("Omitting PGE ip " x64_fmt "\n",
2251				     decoder->ip);
2252			decoder->state.from_ip = 0;
2253			if (decoder->packet.count == 0) {
2254				decoder->state.to_ip = 0;
2255			} else {
2256				intel_pt_set_ip(decoder);
2257				decoder->state.to_ip = decoder->ip;
2258			}
2259			decoder->state.type |= INTEL_PT_TRACE_BEGIN;
2260			intel_pt_mtc_cyc_cnt_pge(decoder);
2261			intel_pt_set_nr(decoder);
2262			return 0;
2263
2264		case INTEL_PT_TIP:
2265			decoder->state.from_ip = decoder->ip;
2266			if (decoder->packet.count == 0) {
2267				decoder->state.to_ip = 0;
2268			} else {
2269				intel_pt_set_ip(decoder);
2270				decoder->state.to_ip = decoder->ip;
2271			}
2272			intel_pt_update_nr(decoder);
2273			intel_pt_sample_iflag_chg(decoder);
2274			return 0;
2275
2276		case INTEL_PT_PIP:
2277			intel_pt_update_pip(decoder);
2278			break;
2279
2280		case INTEL_PT_MTC:
2281			intel_pt_calc_mtc_timestamp(decoder);
2282			if (decoder->period_type == INTEL_PT_PERIOD_MTC)
2283				decoder->state.type |= INTEL_PT_INSTRUCTION;
2284			break;
2285
2286		case INTEL_PT_CYC:
2287			intel_pt_calc_cyc_timestamp(decoder);
2288			break;
2289
2290		case INTEL_PT_MODE_EXEC:
2291			intel_pt_mode_exec(decoder);
2292			break;
2293
2294		case INTEL_PT_VMCS:
2295		case INTEL_PT_MNT:
2296		case INTEL_PT_PAD:
2297			break;
2298
2299		default:
2300			return intel_pt_bug(decoder);
2301		}
2302	}
2303}
2304
2305static int intel_pt_resample(struct intel_pt_decoder *decoder)
2306{
2307	decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2308	decoder->state.type = INTEL_PT_INSTRUCTION;
2309	decoder->state.from_ip = decoder->ip;
2310	decoder->state.to_ip = 0;
2311	return 0;
2312}
2313
2314struct intel_pt_vm_tsc_info {
2315	struct intel_pt_pkt pip_packet;
2316	struct intel_pt_pkt vmcs_packet;
2317	struct intel_pt_pkt tma_packet;
2318	bool tsc, pip, vmcs, tma, psbend;
2319	uint64_t ctc_delta;
2320	uint64_t last_ctc;
2321	int max_lookahead;
2322};
2323
2324/* Lookahead and get the PIP, VMCS and TMA packets from PSB+ */
2325static int intel_pt_vm_psb_lookahead_cb(struct intel_pt_pkt_info *pkt_info)
2326{
2327	struct intel_pt_vm_tsc_info *data = pkt_info->data;
2328
2329	switch (pkt_info->packet.type) {
2330	case INTEL_PT_PAD:
2331	case INTEL_PT_MNT:
2332	case INTEL_PT_MODE_EXEC:
2333	case INTEL_PT_MODE_TSX:
2334	case INTEL_PT_MTC:
2335	case INTEL_PT_FUP:
2336	case INTEL_PT_CYC:
2337	case INTEL_PT_CBR:
2338		break;
2339
2340	case INTEL_PT_TSC:
2341		data->tsc = true;
2342		break;
2343
2344	case INTEL_PT_TMA:
2345		data->tma_packet = pkt_info->packet;
2346		data->tma = true;
2347		break;
2348
2349	case INTEL_PT_PIP:
2350		data->pip_packet = pkt_info->packet;
2351		data->pip = true;
2352		break;
2353
2354	case INTEL_PT_VMCS:
2355		data->vmcs_packet = pkt_info->packet;
2356		data->vmcs = true;
2357		break;
2358
2359	case INTEL_PT_PSBEND:
2360		data->psbend = true;
2361		return 1;
2362
2363	case INTEL_PT_TIP_PGE:
2364	case INTEL_PT_PTWRITE:
2365	case INTEL_PT_PTWRITE_IP:
2366	case INTEL_PT_EXSTOP:
2367	case INTEL_PT_EXSTOP_IP:
2368	case INTEL_PT_MWAIT:
2369	case INTEL_PT_PWRE:
2370	case INTEL_PT_PWRX:
2371	case INTEL_PT_BBP:
2372	case INTEL_PT_BIP:
2373	case INTEL_PT_BEP:
2374	case INTEL_PT_BEP_IP:
2375	case INTEL_PT_OVF:
2376	case INTEL_PT_BAD:
2377	case INTEL_PT_TNT:
2378	case INTEL_PT_TIP_PGD:
2379	case INTEL_PT_TIP:
2380	case INTEL_PT_PSB:
2381	case INTEL_PT_TRACESTOP:
2382	case INTEL_PT_CFE:
2383	case INTEL_PT_CFE_IP:
2384	case INTEL_PT_EVD:
2385	default:
2386		return 1;
2387	}
2388
2389	return 0;
2390}
2391
2392struct intel_pt_ovf_fup_info {
2393	int max_lookahead;
2394	bool found;
2395};
2396
2397/* Lookahead to detect a FUP packet after OVF */
2398static int intel_pt_ovf_fup_lookahead_cb(struct intel_pt_pkt_info *pkt_info)
2399{
2400	struct intel_pt_ovf_fup_info *data = pkt_info->data;
2401
2402	if (pkt_info->packet.type == INTEL_PT_CYC ||
2403	    pkt_info->packet.type == INTEL_PT_MTC ||
2404	    pkt_info->packet.type == INTEL_PT_TSC)
2405		return !--(data->max_lookahead);
2406	data->found = pkt_info->packet.type == INTEL_PT_FUP;
2407	return 1;
2408}
2409
2410static bool intel_pt_ovf_fup_lookahead(struct intel_pt_decoder *decoder)
2411{
2412	struct intel_pt_ovf_fup_info data = {
2413		.max_lookahead = 16,
2414		.found = false,
2415	};
2416
2417	intel_pt_pkt_lookahead(decoder, intel_pt_ovf_fup_lookahead_cb, &data);
2418	return data.found;
2419}
2420
2421/* Lookahead and get the TMA packet after TSC */
2422static int intel_pt_tma_lookahead_cb(struct intel_pt_pkt_info *pkt_info)
2423{
2424	struct intel_pt_vm_tsc_info *data = pkt_info->data;
2425
2426	if (pkt_info->packet.type == INTEL_PT_CYC ||
2427	    pkt_info->packet.type == INTEL_PT_MTC)
2428		return !--(data->max_lookahead);
2429
2430	if (pkt_info->packet.type == INTEL_PT_TMA) {
2431		data->tma_packet = pkt_info->packet;
2432		data->tma = true;
2433	}
2434	return 1;
2435}
2436
2437static uint64_t intel_pt_ctc_to_tsc(struct intel_pt_decoder *decoder, uint64_t ctc)
2438{
2439	if (decoder->tsc_ctc_mult)
2440		return ctc * decoder->tsc_ctc_mult;
2441	else
2442		return multdiv(ctc, decoder->tsc_ctc_ratio_n, decoder->tsc_ctc_ratio_d);
2443}
2444
2445static uint64_t intel_pt_calc_expected_tsc(struct intel_pt_decoder *decoder,
2446					   uint32_t ctc,
2447					   uint32_t fc,
2448					   uint64_t last_ctc_timestamp,
2449					   uint64_t ctc_delta,
2450					   uint32_t last_ctc)
2451{
2452	/* Number of CTC ticks from last_ctc_timestamp to last_mtc */
2453	uint64_t last_mtc_ctc = last_ctc + ctc_delta;
2454	/*
2455	 * Number of CTC ticks from there until current TMA packet. We would
2456	 * expect last_mtc_ctc to be before ctc, but the TSC packet can slip
2457	 * past an MTC, so a sign-extended value is used.
2458	 */
2459	uint64_t delta = (int16_t)((uint16_t)ctc - (uint16_t)last_mtc_ctc);
2460	/* Total CTC ticks from last_ctc_timestamp to current TMA packet */
2461	uint64_t new_ctc_delta = ctc_delta + delta;
2462	uint64_t expected_tsc;
2463
2464	/*
2465	 * Convert CTC ticks to TSC ticks, add the starting point
2466	 * (last_ctc_timestamp) and the fast counter from the TMA packet.
2467	 */
2468	expected_tsc = last_ctc_timestamp + intel_pt_ctc_to_tsc(decoder, new_ctc_delta) + fc;
2469
2470	if (intel_pt_enable_logging) {
2471		intel_pt_log_x64(last_mtc_ctc);
2472		intel_pt_log_x32(last_ctc);
2473		intel_pt_log_x64(ctc_delta);
2474		intel_pt_log_x64(delta);
2475		intel_pt_log_x32(ctc);
2476		intel_pt_log_x64(new_ctc_delta);
2477		intel_pt_log_x64(last_ctc_timestamp);
2478		intel_pt_log_x32(fc);
2479		intel_pt_log_x64(intel_pt_ctc_to_tsc(decoder, new_ctc_delta));
2480		intel_pt_log_x64(expected_tsc);
2481	}
2482
2483	return expected_tsc;
2484}
2485
2486static uint64_t intel_pt_expected_tsc(struct intel_pt_decoder *decoder,
2487				      struct intel_pt_vm_tsc_info *data)
2488{
2489	uint32_t ctc = data->tma_packet.payload;
2490	uint32_t fc = data->tma_packet.count;
2491
2492	return intel_pt_calc_expected_tsc(decoder, ctc, fc,
2493					  decoder->ctc_timestamp,
2494					  data->ctc_delta, data->last_ctc);
2495}
2496
2497static void intel_pt_translate_vm_tsc(struct intel_pt_decoder *decoder,
2498				      struct intel_pt_vmcs_info *vmcs_info)
2499{
2500	uint64_t payload = decoder->packet.payload;
2501
2502	/* VMX adds the TSC Offset, so subtract to get host TSC */
2503	decoder->packet.payload -= vmcs_info->tsc_offset;
2504	/* TSC packet has only 7 bytes */
2505	decoder->packet.payload &= SEVEN_BYTES;
2506
2507	/*
2508	 * The buffer is mmapped from the data file, so this also updates the
2509	 * data file.
2510	 */
2511	if (!decoder->vm_tm_corr_dry_run)
2512		memcpy((void *)decoder->buf + 1, &decoder->packet.payload, 7);
2513
2514	intel_pt_log("Translated VM TSC %#" PRIx64 " -> %#" PRIx64
2515		     "    VMCS %#" PRIx64 "    TSC Offset %#" PRIx64 "\n",
2516		     payload, decoder->packet.payload, vmcs_info->vmcs,
2517		     vmcs_info->tsc_offset);
2518}
2519
2520static void intel_pt_translate_vm_tsc_offset(struct intel_pt_decoder *decoder,
2521					     uint64_t tsc_offset)
2522{
2523	struct intel_pt_vmcs_info vmcs_info = {
2524		.vmcs = NO_VMCS,
2525		.tsc_offset = tsc_offset
2526	};
2527
2528	intel_pt_translate_vm_tsc(decoder, &vmcs_info);
2529}
2530
2531static inline bool in_vm(uint64_t pip_payload)
2532{
2533	return pip_payload & 1;
2534}
2535
2536static inline bool pip_in_vm(struct intel_pt_pkt *pip_packet)
2537{
2538	return pip_packet->payload & 1;
2539}
2540
2541static void intel_pt_print_vmcs_info(struct intel_pt_vmcs_info *vmcs_info)
2542{
2543	p_log("VMCS: %#" PRIx64 "  TSC Offset %#" PRIx64,
2544	      vmcs_info->vmcs, vmcs_info->tsc_offset);
2545}
2546
2547static void intel_pt_vm_tm_corr_psb(struct intel_pt_decoder *decoder,
2548				    struct intel_pt_vm_tsc_info *data)
2549{
2550	memset(data, 0, sizeof(*data));
2551	data->ctc_delta = decoder->ctc_delta;
2552	data->last_ctc = decoder->last_ctc;
2553	intel_pt_pkt_lookahead(decoder, intel_pt_vm_psb_lookahead_cb, data);
2554	if (data->tsc && !data->psbend)
2555		p_log("ERROR: PSB without PSBEND");
2556	decoder->in_psb = data->psbend;
2557}
2558
2559static void intel_pt_vm_tm_corr_first_tsc(struct intel_pt_decoder *decoder,
2560					  struct intel_pt_vm_tsc_info *data,
2561					  struct intel_pt_vmcs_info *vmcs_info,
2562					  uint64_t host_tsc)
2563{
2564	if (!decoder->in_psb) {
2565		/* Can't happen */
2566		p_log("ERROR: First TSC is not in PSB+");
2567	}
2568
2569	if (data->pip) {
2570		if (pip_in_vm(&data->pip_packet)) { /* Guest */
2571			if (vmcs_info && vmcs_info->tsc_offset) {
2572				intel_pt_translate_vm_tsc(decoder, vmcs_info);
2573				decoder->vm_tm_corr_reliable = true;
2574			} else {
2575				p_log("ERROR: First TSC, unknown TSC Offset");
2576			}
2577		} else { /* Host */
2578			decoder->vm_tm_corr_reliable = true;
2579		}
2580	} else { /* Host or Guest */
2581		decoder->vm_tm_corr_reliable = false;
2582		if (intel_pt_time_in_range(decoder, host_tsc)) {
2583			/* Assume Host */
2584		} else {
2585			/* Assume Guest */
2586			if (vmcs_info && vmcs_info->tsc_offset)
2587				intel_pt_translate_vm_tsc(decoder, vmcs_info);
2588			else
2589				p_log("ERROR: First TSC, no PIP, unknown TSC Offset");
2590		}
2591	}
2592}
2593
2594static void intel_pt_vm_tm_corr_tsc(struct intel_pt_decoder *decoder,
2595				    struct intel_pt_vm_tsc_info *data)
2596{
2597	struct intel_pt_vmcs_info *vmcs_info;
2598	uint64_t tsc_offset = 0;
2599	uint64_t vmcs;
2600	bool reliable = true;
2601	uint64_t expected_tsc;
2602	uint64_t host_tsc;
2603	uint64_t ref_timestamp;
2604
2605	bool assign = false;
2606	bool assign_reliable = false;
2607
2608	/* Already have 'data' for the in_psb case */
2609	if (!decoder->in_psb) {
2610		memset(data, 0, sizeof(*data));
2611		data->ctc_delta = decoder->ctc_delta;
2612		data->last_ctc = decoder->last_ctc;
2613		data->max_lookahead = 16;
2614		intel_pt_pkt_lookahead(decoder, intel_pt_tma_lookahead_cb, data);
2615		if (decoder->pge) {
2616			data->pip = true;
2617			data->pip_packet.payload = decoder->pip_payload;
2618		}
2619	}
2620
2621	/* Calculations depend on having TMA packets */
2622	if (!data->tma) {
2623		p_log("ERROR: TSC without TMA");
2624		return;
2625	}
2626
2627	vmcs = data->vmcs ? data->vmcs_packet.payload : decoder->vmcs;
2628	if (vmcs == NO_VMCS)
2629		vmcs = 0;
2630
2631	vmcs_info = decoder->findnew_vmcs_info(decoder->data, vmcs);
2632
2633	ref_timestamp = decoder->timestamp ? decoder->timestamp : decoder->buf_timestamp;
2634	host_tsc = intel_pt_8b_tsc(decoder->packet.payload, ref_timestamp);
2635
2636	if (!decoder->ctc_timestamp) {
2637		intel_pt_vm_tm_corr_first_tsc(decoder, data, vmcs_info, host_tsc);
2638		return;
2639	}
2640
2641	expected_tsc = intel_pt_expected_tsc(decoder, data);
2642
2643	tsc_offset = host_tsc - expected_tsc;
2644
2645	/* Determine if TSC is from Host or Guest */
2646	if (data->pip) {
2647		if (pip_in_vm(&data->pip_packet)) { /* Guest */
2648			if (!vmcs_info) {
2649				/* PIP NR=1 without VMCS cannot happen */
2650				p_log("ERROR: Missing VMCS");
2651				intel_pt_translate_vm_tsc_offset(decoder, tsc_offset);
2652				decoder->vm_tm_corr_reliable = false;
2653				return;
2654			}
2655		} else { /* Host */
2656			decoder->last_reliable_timestamp = host_tsc;
2657			decoder->vm_tm_corr_reliable = true;
2658			return;
2659		}
2660	} else { /* Host or Guest */
2661		reliable = false; /* Host/Guest is a guess, so not reliable */
2662		if (decoder->in_psb) {
2663			if (!tsc_offset)
2664				return; /* Zero TSC Offset, assume Host */
2665			/*
2666			 * TSC packet has only 7 bytes of TSC. We have no
2667			 * information about the Guest's 8th byte, but it
2668			 * doesn't matter because we only need 7 bytes.
2669			 * Here, since the 8th byte is unreliable and
2670			 * irrelevant, compare only 7 byes.
2671			 */
2672			if (vmcs_info &&
2673			    (tsc_offset & SEVEN_BYTES) ==
2674			    (vmcs_info->tsc_offset & SEVEN_BYTES)) {
2675				/* Same TSC Offset as last VMCS, assume Guest */
2676				goto guest;
2677			}
2678		}
2679		/*
2680		 * Check if the host_tsc is within the expected range.
2681		 * Note, we could narrow the range more by looking ahead for
2682		 * the next host TSC in the same buffer, but we don't bother to
2683		 * do that because this is probably good enough.
2684		 */
2685		if (host_tsc >= expected_tsc && intel_pt_time_in_range(decoder, host_tsc)) {
2686			/* Within expected range for Host TSC, assume Host */
2687			decoder->vm_tm_corr_reliable = false;
2688			return;
2689		}
2690	}
2691
2692guest: /* Assuming Guest */
2693
2694	/* Determine whether to assign TSC Offset */
2695	if (vmcs_info && vmcs_info->vmcs) {
2696		if (vmcs_info->tsc_offset && vmcs_info->reliable) {
2697			assign = false;
2698		} else if (decoder->in_psb && data->pip && decoder->vm_tm_corr_reliable &&
2699			   decoder->vm_tm_corr_continuous && decoder->vm_tm_corr_same_buf) {
2700			/* Continuous tracing, TSC in a PSB is not a time loss */
2701			assign = true;
2702			assign_reliable = true;
2703		} else if (decoder->in_psb && data->pip && decoder->vm_tm_corr_same_buf) {
2704			/*
2705			 * Unlikely to be a time loss TSC in a PSB which is not
2706			 * at the start of a buffer.
2707			 */
2708			assign = true;
2709			assign_reliable = false;
2710		}
2711	}
2712
2713	/* Record VMCS TSC Offset */
2714	if (assign && (vmcs_info->tsc_offset != tsc_offset ||
2715		       vmcs_info->reliable != assign_reliable)) {
2716		bool print = vmcs_info->tsc_offset != tsc_offset;
2717
2718		vmcs_info->tsc_offset = tsc_offset;
2719		vmcs_info->reliable = assign_reliable;
2720		if (print)
2721			intel_pt_print_vmcs_info(vmcs_info);
2722	}
2723
2724	/* Determine what TSC Offset to use */
2725	if (vmcs_info && vmcs_info->tsc_offset) {
2726		if (!vmcs_info->reliable)
2727			reliable = false;
2728		intel_pt_translate_vm_tsc(decoder, vmcs_info);
2729	} else {
2730		reliable = false;
2731		if (vmcs_info) {
2732			if (!vmcs_info->error_printed) {
2733				p_log("ERROR: Unknown TSC Offset for VMCS %#" PRIx64,
2734				      vmcs_info->vmcs);
2735				vmcs_info->error_printed = true;
2736			}
2737		} else {
2738			if (intel_pt_print_once(decoder, INTEL_PT_PRT_ONCE_UNK_VMCS))
2739				p_log("ERROR: Unknown VMCS");
2740		}
2741		intel_pt_translate_vm_tsc_offset(decoder, tsc_offset);
2742	}
2743
2744	decoder->vm_tm_corr_reliable = reliable;
2745}
2746
2747static void intel_pt_vm_tm_corr_pebs_tsc(struct intel_pt_decoder *decoder)
2748{
2749	uint64_t host_tsc = decoder->packet.payload;
2750	uint64_t guest_tsc = decoder->packet.payload;
2751	struct intel_pt_vmcs_info *vmcs_info;
2752	uint64_t vmcs;
2753
2754	vmcs = decoder->vmcs;
2755	if (vmcs == NO_VMCS)
2756		vmcs = 0;
2757
2758	vmcs_info = decoder->findnew_vmcs_info(decoder->data, vmcs);
2759
2760	if (decoder->pge) {
2761		if (in_vm(decoder->pip_payload)) { /* Guest */
2762			if (!vmcs_info) {
2763				/* PIP NR=1 without VMCS cannot happen */
2764				p_log("ERROR: Missing VMCS");
2765			}
2766		} else { /* Host */
2767			return;
2768		}
2769	} else { /* Host or Guest */
2770		if (intel_pt_time_in_range(decoder, host_tsc)) {
2771			/* Within expected range for Host TSC, assume Host */
2772			return;
2773		}
2774	}
2775
2776	if (vmcs_info) {
2777		/* Translate Guest TSC to Host TSC */
2778		host_tsc = ((guest_tsc & SEVEN_BYTES) - vmcs_info->tsc_offset) & SEVEN_BYTES;
2779		host_tsc = intel_pt_8b_tsc(host_tsc, decoder->timestamp);
2780		intel_pt_log("Translated VM TSC %#" PRIx64 " -> %#" PRIx64
2781			     "    VMCS %#" PRIx64 "    TSC Offset %#" PRIx64 "\n",
2782			     guest_tsc, host_tsc, vmcs_info->vmcs,
2783			     vmcs_info->tsc_offset);
2784		if (!intel_pt_time_in_range(decoder, host_tsc) &&
2785		    intel_pt_print_once(decoder, INTEL_PT_PRT_ONCE_ERANGE))
2786			p_log("Timestamp out of range");
2787	} else {
2788		if (intel_pt_print_once(decoder, INTEL_PT_PRT_ONCE_UNK_VMCS))
2789			p_log("ERROR: Unknown VMCS");
2790		host_tsc = decoder->timestamp;
2791	}
2792
2793	decoder->packet.payload = host_tsc;
2794
2795	if (!decoder->vm_tm_corr_dry_run)
2796		memcpy((void *)decoder->buf + 1, &host_tsc, 8);
2797}
2798
2799static int intel_pt_vm_time_correlation(struct intel_pt_decoder *decoder)
2800{
2801	struct intel_pt_vm_tsc_info data = { .psbend = false };
2802	bool pge;
2803	int err;
2804
2805	if (decoder->in_psb)
2806		intel_pt_vm_tm_corr_psb(decoder, &data);
2807
2808	while (1) {
2809		err = intel_pt_get_next_packet(decoder);
2810		if (err == -ENOLINK)
2811			continue;
2812		if (err)
2813			break;
2814
2815		switch (decoder->packet.type) {
2816		case INTEL_PT_TIP_PGD:
2817			decoder->pge = false;
2818			decoder->vm_tm_corr_continuous = false;
2819			break;
2820
2821		case INTEL_PT_TNT:
2822		case INTEL_PT_TIP:
2823		case INTEL_PT_TIP_PGE:
2824			decoder->pge = true;
2825			break;
2826
2827		case INTEL_PT_OVF:
2828			decoder->in_psb = false;
2829			pge = decoder->pge;
2830			decoder->pge = intel_pt_ovf_fup_lookahead(decoder);
2831			if (pge != decoder->pge)
2832				intel_pt_log("Surprising PGE change in OVF!");
2833			if (!decoder->pge)
2834				decoder->vm_tm_corr_continuous = false;
2835			break;
2836
2837		case INTEL_PT_FUP:
2838			if (decoder->in_psb)
2839				decoder->pge = true;
2840			break;
2841
2842		case INTEL_PT_TRACESTOP:
2843			decoder->pge = false;
2844			decoder->vm_tm_corr_continuous = false;
2845			decoder->have_tma = false;
2846			break;
2847
2848		case INTEL_PT_PSB:
2849			intel_pt_vm_tm_corr_psb(decoder, &data);
2850			break;
2851
2852		case INTEL_PT_PIP:
2853			decoder->pip_payload = decoder->packet.payload;
2854			break;
2855
2856		case INTEL_PT_MTC:
2857			intel_pt_calc_mtc_timestamp(decoder);
2858			break;
2859
2860		case INTEL_PT_TSC:
2861			intel_pt_vm_tm_corr_tsc(decoder, &data);
2862			intel_pt_calc_tsc_timestamp(decoder);
2863			decoder->vm_tm_corr_same_buf = true;
2864			decoder->vm_tm_corr_continuous = decoder->pge;
2865			break;
2866
2867		case INTEL_PT_TMA:
2868			intel_pt_calc_tma(decoder);
2869			break;
2870
2871		case INTEL_PT_CYC:
2872			intel_pt_calc_cyc_timestamp(decoder);
2873			break;
2874
2875		case INTEL_PT_CBR:
2876			intel_pt_calc_cbr(decoder);
2877			break;
2878
2879		case INTEL_PT_PSBEND:
2880			decoder->in_psb = false;
2881			data.psbend = false;
2882			break;
2883
2884		case INTEL_PT_VMCS:
2885			if (decoder->packet.payload != NO_VMCS)
2886				decoder->vmcs = decoder->packet.payload;
2887			break;
2888
2889		case INTEL_PT_BBP:
2890			decoder->blk_type = decoder->packet.payload;
2891			break;
2892
2893		case INTEL_PT_BIP:
2894			if (decoder->blk_type == INTEL_PT_PEBS_BASIC &&
2895			    decoder->packet.count == 2)
2896				intel_pt_vm_tm_corr_pebs_tsc(decoder);
2897			break;
2898
2899		case INTEL_PT_BEP:
2900		case INTEL_PT_BEP_IP:
2901			decoder->blk_type = 0;
2902			break;
2903
2904		case INTEL_PT_CFE:
2905		case INTEL_PT_CFE_IP:
2906		case INTEL_PT_EVD:
2907		case INTEL_PT_MODE_EXEC:
2908		case INTEL_PT_MODE_TSX:
2909		case INTEL_PT_MNT:
2910		case INTEL_PT_PAD:
2911		case INTEL_PT_PTWRITE_IP:
2912		case INTEL_PT_PTWRITE:
2913		case INTEL_PT_MWAIT:
2914		case INTEL_PT_PWRE:
2915		case INTEL_PT_EXSTOP_IP:
2916		case INTEL_PT_EXSTOP:
2917		case INTEL_PT_PWRX:
2918		case INTEL_PT_BAD: /* Does not happen */
2919		default:
2920			break;
2921		}
2922	}
2923
2924	return err;
2925}
2926
2927#define HOP_PROCESS	0
2928#define HOP_IGNORE	1
2929#define HOP_RETURN	2
2930#define HOP_AGAIN	3
2931
2932static int intel_pt_scan_for_psb(struct intel_pt_decoder *decoder);
2933
2934/* Hop mode: Ignore TNT, do not walk code, but get ip from FUPs and TIPs */
2935static int intel_pt_hop_trace(struct intel_pt_decoder *decoder, bool *no_tip, int *err)
2936{
2937	*err = 0;
2938
2939	/* Leap from PSB to PSB, getting ip from FUP within PSB+ */
2940	if (decoder->leap && !decoder->in_psb && decoder->packet.type != INTEL_PT_PSB) {
2941		*err = intel_pt_scan_for_psb(decoder);
2942		if (*err)
2943			return HOP_RETURN;
2944	}
2945
2946	switch (decoder->packet.type) {
2947	case INTEL_PT_TNT:
2948		return HOP_IGNORE;
2949
2950	case INTEL_PT_TIP_PGD:
2951		decoder->pge = false;
2952		if (!decoder->packet.count) {
2953			intel_pt_set_nr(decoder);
2954			return HOP_IGNORE;
2955		}
2956		intel_pt_set_ip(decoder);
2957		decoder->state.type |= INTEL_PT_TRACE_END;
2958		decoder->state.from_ip = 0;
2959		decoder->state.to_ip = decoder->ip;
2960		intel_pt_update_nr(decoder);
2961		return HOP_RETURN;
2962
2963	case INTEL_PT_TIP:
2964		if (!decoder->packet.count) {
2965			intel_pt_set_nr(decoder);
2966			return HOP_IGNORE;
2967		}
2968		intel_pt_set_ip(decoder);
2969		decoder->state.type = INTEL_PT_INSTRUCTION;
2970		decoder->state.from_ip = decoder->ip;
2971		decoder->state.to_ip = 0;
2972		intel_pt_update_nr(decoder);
2973		intel_pt_sample_iflag_chg(decoder);
2974		return HOP_RETURN;
2975
2976	case INTEL_PT_FUP:
2977		if (!decoder->packet.count)
2978			return HOP_IGNORE;
2979		intel_pt_set_ip(decoder);
2980		if (decoder->set_fup_mwait || decoder->set_fup_pwre)
2981			*no_tip = true;
2982		if (!decoder->branch_enable || !decoder->pge)
2983			*no_tip = true;
2984		if (*no_tip) {
2985			decoder->state.type = INTEL_PT_INSTRUCTION;
2986			decoder->state.from_ip = decoder->ip;
2987			decoder->state.to_ip = 0;
2988			intel_pt_fup_event(decoder, *no_tip);
2989			return HOP_RETURN;
2990		}
2991		intel_pt_fup_event(decoder, *no_tip);
2992		decoder->state.type |= INTEL_PT_INSTRUCTION | INTEL_PT_BRANCH;
2993		*err = intel_pt_walk_fup_tip(decoder);
2994		if (!*err && decoder->state.to_ip)
2995			decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
2996		return HOP_RETURN;
2997
2998	case INTEL_PT_PSB:
2999		decoder->state.psb_offset = decoder->pos;
3000		decoder->psb_ip = 0;
3001		decoder->last_ip = 0;
3002		decoder->have_last_ip = true;
 
3003		*err = intel_pt_walk_psbend(decoder);
3004		if (*err == -EAGAIN)
3005			return HOP_AGAIN;
3006		if (*err)
3007			return HOP_RETURN;
3008		decoder->state.type = INTEL_PT_PSB_EVT;
3009		if (decoder->psb_ip) {
3010			decoder->state.type |= INTEL_PT_INSTRUCTION;
3011			decoder->ip = decoder->psb_ip;
 
 
3012		}
3013		decoder->state.from_ip = decoder->psb_ip;
3014		decoder->state.to_ip = 0;
3015		return HOP_RETURN;
 
 
3016
3017	case INTEL_PT_BAD:
3018	case INTEL_PT_PAD:
3019	case INTEL_PT_TIP_PGE:
3020	case INTEL_PT_TSC:
3021	case INTEL_PT_TMA:
3022	case INTEL_PT_MODE_EXEC:
3023	case INTEL_PT_MODE_TSX:
3024	case INTEL_PT_MTC:
3025	case INTEL_PT_CYC:
3026	case INTEL_PT_VMCS:
3027	case INTEL_PT_PSBEND:
3028	case INTEL_PT_CBR:
3029	case INTEL_PT_TRACESTOP:
3030	case INTEL_PT_PIP:
3031	case INTEL_PT_OVF:
3032	case INTEL_PT_MNT:
3033	case INTEL_PT_PTWRITE:
3034	case INTEL_PT_PTWRITE_IP:
3035	case INTEL_PT_EXSTOP:
3036	case INTEL_PT_EXSTOP_IP:
3037	case INTEL_PT_MWAIT:
3038	case INTEL_PT_PWRE:
3039	case INTEL_PT_PWRX:
3040	case INTEL_PT_BBP:
3041	case INTEL_PT_BIP:
3042	case INTEL_PT_BEP:
3043	case INTEL_PT_BEP_IP:
3044	case INTEL_PT_CFE:
3045	case INTEL_PT_CFE_IP:
3046	case INTEL_PT_EVD:
3047	default:
3048		return HOP_PROCESS;
3049	}
3050}
3051
3052struct intel_pt_psb_info {
3053	struct intel_pt_pkt fup_packet;
3054	bool fup;
3055	int after_psbend;
3056};
3057
3058/* Lookahead and get the FUP packet from PSB+ */
3059static int intel_pt_psb_lookahead_cb(struct intel_pt_pkt_info *pkt_info)
3060{
3061	struct intel_pt_psb_info *data = pkt_info->data;
3062
3063	switch (pkt_info->packet.type) {
3064	case INTEL_PT_PAD:
3065	case INTEL_PT_MNT:
3066	case INTEL_PT_TSC:
3067	case INTEL_PT_TMA:
3068	case INTEL_PT_MODE_EXEC:
3069	case INTEL_PT_MODE_TSX:
3070	case INTEL_PT_MTC:
3071	case INTEL_PT_CYC:
3072	case INTEL_PT_VMCS:
3073	case INTEL_PT_CBR:
3074	case INTEL_PT_PIP:
3075		if (data->after_psbend) {
3076			data->after_psbend -= 1;
3077			if (!data->after_psbend)
3078				return 1;
3079		}
3080		break;
3081
3082	case INTEL_PT_FUP:
3083		if (data->after_psbend)
3084			return 1;
3085		if (data->fup || pkt_info->packet.count == 0)
3086			return 1;
3087		data->fup_packet = pkt_info->packet;
3088		data->fup = true;
3089		break;
3090
3091	case INTEL_PT_PSBEND:
3092		if (!data->fup)
3093			return 1;
3094		/* Keep going to check for a TIP.PGE */
3095		data->after_psbend = 6;
3096		break;
3097
3098	case INTEL_PT_TIP_PGE:
3099		/* Ignore FUP in PSB+ if followed by TIP.PGE */
3100		if (data->after_psbend)
3101			data->fup = false;
3102		return 1;
3103
3104	case INTEL_PT_PTWRITE:
3105	case INTEL_PT_PTWRITE_IP:
3106	case INTEL_PT_EXSTOP:
3107	case INTEL_PT_EXSTOP_IP:
3108	case INTEL_PT_MWAIT:
3109	case INTEL_PT_PWRE:
3110	case INTEL_PT_PWRX:
3111	case INTEL_PT_BBP:
3112	case INTEL_PT_BIP:
3113	case INTEL_PT_BEP:
3114	case INTEL_PT_BEP_IP:
3115	case INTEL_PT_CFE:
3116	case INTEL_PT_CFE_IP:
3117	case INTEL_PT_EVD:
3118		if (data->after_psbend) {
3119			data->after_psbend -= 1;
3120			if (!data->after_psbend)
3121				return 1;
3122			break;
3123		}
3124		return 1;
3125
3126	case INTEL_PT_OVF:
3127	case INTEL_PT_BAD:
3128	case INTEL_PT_TNT:
3129	case INTEL_PT_TIP_PGD:
3130	case INTEL_PT_TIP:
3131	case INTEL_PT_PSB:
3132	case INTEL_PT_TRACESTOP:
3133	default:
3134		return 1;
3135	}
3136
3137	return 0;
3138}
3139
3140static int intel_pt_psb(struct intel_pt_decoder *decoder)
3141{
3142	int err;
3143
3144	decoder->last_ip = 0;
3145	decoder->psb_ip = 0;
3146	decoder->have_last_ip = true;
3147	intel_pt_clear_stack(&decoder->stack);
3148	err = intel_pt_walk_psbend(decoder);
3149	if (err)
3150		return err;
3151	decoder->state.type = INTEL_PT_PSB_EVT;
3152	decoder->state.from_ip = decoder->psb_ip;
3153	decoder->state.to_ip = 0;
3154	return 0;
3155}
3156
3157static int intel_pt_fup_in_psb(struct intel_pt_decoder *decoder)
3158{
3159	int err;
3160
3161	if (decoder->ip != decoder->last_ip) {
3162		err = intel_pt_walk_fup(decoder);
3163		if (!err || err != -EAGAIN)
3164			return err;
3165	}
3166
3167	decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
3168	err = intel_pt_psb(decoder);
3169	if (err) {
3170		decoder->pkt_state = INTEL_PT_STATE_ERR3;
3171		return -ENOENT;
3172	}
3173
3174	return 0;
3175}
3176
3177static bool intel_pt_psb_with_fup(struct intel_pt_decoder *decoder, int *err)
3178{
3179	struct intel_pt_psb_info data = { .fup = false };
3180
3181	if (!decoder->branch_enable)
3182		return false;
3183
3184	intel_pt_pkt_lookahead(decoder, intel_pt_psb_lookahead_cb, &data);
3185	if (!data.fup)
3186		return false;
3187
3188	decoder->packet = data.fup_packet;
3189	intel_pt_set_last_ip(decoder);
3190	decoder->pkt_state = INTEL_PT_STATE_FUP_IN_PSB;
3191
3192	*err = intel_pt_fup_in_psb(decoder);
3193
3194	return true;
3195}
3196
3197static int intel_pt_walk_trace(struct intel_pt_decoder *decoder)
3198{
3199	int last_packet_type = INTEL_PT_PAD;
3200	bool no_tip = false;
3201	int err;
3202
3203	while (1) {
3204		err = intel_pt_get_next_packet(decoder);
3205		if (err)
3206			return err;
3207next:
3208		err = 0;
3209		if (decoder->cyc_threshold) {
3210			if (decoder->sample_cyc && last_packet_type != INTEL_PT_CYC)
3211				decoder->sample_cyc = false;
3212			last_packet_type = decoder->packet.type;
3213		}
3214
3215		if (decoder->hop) {
3216			switch (intel_pt_hop_trace(decoder, &no_tip, &err)) {
3217			case HOP_IGNORE:
3218				continue;
3219			case HOP_RETURN:
3220				return err;
3221			case HOP_AGAIN:
3222				goto next;
3223			default:
3224				break;
3225			}
3226		}
3227
3228		switch (decoder->packet.type) {
3229		case INTEL_PT_TNT:
3230			if (!decoder->packet.count)
3231				break;
3232			decoder->tnt = decoder->packet;
3233			decoder->pkt_state = INTEL_PT_STATE_TNT;
3234			err = intel_pt_walk_tnt(decoder);
3235			if (err == -EAGAIN)
3236				break;
3237			return err;
3238
3239		case INTEL_PT_TIP_PGD:
3240			if (decoder->packet.count != 0)
3241				intel_pt_set_last_ip(decoder);
3242			decoder->pkt_state = INTEL_PT_STATE_TIP_PGD;
3243			return intel_pt_walk_tip(decoder);
3244
3245		case INTEL_PT_TIP_PGE: {
3246			decoder->pge = true;
3247			decoder->overflow = false;
3248			intel_pt_mtc_cyc_cnt_pge(decoder);
3249			intel_pt_set_nr(decoder);
3250			if (decoder->packet.count == 0) {
3251				intel_pt_log_at("Skipping zero TIP.PGE",
3252						decoder->pos);
3253				break;
3254			}
3255			intel_pt_sample_iflag_chg(decoder);
3256			intel_pt_set_ip(decoder);
3257			decoder->state.from_ip = 0;
3258			decoder->state.to_ip = decoder->ip;
3259			decoder->state.type |= INTEL_PT_TRACE_BEGIN;
3260			/*
3261			 * In hop mode, resample to get the to_ip as an
3262			 * "instruction" sample.
3263			 */
3264			if (decoder->hop)
3265				decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
3266			return 0;
3267		}
3268
3269		case INTEL_PT_OVF:
3270			return intel_pt_overflow(decoder);
3271
3272		case INTEL_PT_TIP:
3273			if (decoder->packet.count != 0)
3274				intel_pt_set_last_ip(decoder);
3275			decoder->pkt_state = INTEL_PT_STATE_TIP;
3276			return intel_pt_walk_tip(decoder);
3277
3278		case INTEL_PT_FUP:
3279			if (decoder->packet.count == 0) {
3280				intel_pt_log_at("Skipping zero FUP",
3281						decoder->pos);
3282				no_tip = false;
3283				break;
3284			}
3285			intel_pt_set_last_ip(decoder);
3286			if (!decoder->branch_enable || !decoder->pge) {
3287				decoder->ip = decoder->last_ip;
3288				if (intel_pt_fup_event(decoder, no_tip))
3289					return 0;
3290				no_tip = false;
3291				break;
3292			}
3293			if (decoder->set_fup_mwait)
3294				no_tip = true;
3295			if (no_tip)
3296				decoder->pkt_state = INTEL_PT_STATE_FUP_NO_TIP;
3297			else
3298				decoder->pkt_state = INTEL_PT_STATE_FUP;
3299			err = intel_pt_walk_fup(decoder);
3300			if (err != -EAGAIN)
3301				return err;
3302			if (no_tip) {
3303				no_tip = false;
3304				break;
3305			}
3306			return intel_pt_walk_fup_tip(decoder);
3307
3308		case INTEL_PT_TRACESTOP:
3309			decoder->pge = false;
3310			decoder->continuous_period = false;
3311			intel_pt_clear_tx_flags(decoder);
3312			decoder->have_tma = false;
3313			break;
3314
3315		case INTEL_PT_PSB:
3316			decoder->state.psb_offset = decoder->pos;
3317			decoder->psb_ip = 0;
3318			if (intel_pt_psb_with_fup(decoder, &err))
3319				return err;
3320			err = intel_pt_psb(decoder);
3321			if (err == -EAGAIN)
3322				goto next;
3323			return err;
 
 
 
 
 
 
 
 
 
 
 
3324
3325		case INTEL_PT_PIP:
3326			intel_pt_update_pip(decoder);
3327			break;
3328
3329		case INTEL_PT_MTC:
3330			intel_pt_calc_mtc_timestamp(decoder);
3331			if (decoder->period_type != INTEL_PT_PERIOD_MTC)
3332				break;
3333			/*
3334			 * Ensure that there has been an instruction since the
3335			 * last MTC.
3336			 */
3337			if (!decoder->mtc_insn)
3338				break;
3339			decoder->mtc_insn = false;
3340			/* Ensure that there is a timestamp */
3341			if (!decoder->timestamp)
3342				break;
3343			decoder->state.type = INTEL_PT_INSTRUCTION;
3344			decoder->state.from_ip = decoder->ip;
3345			decoder->state.to_ip = 0;
3346			decoder->mtc_insn = false;
3347			return 0;
3348
3349		case INTEL_PT_TSC:
3350			intel_pt_calc_tsc_timestamp(decoder);
3351			break;
3352
3353		case INTEL_PT_TMA:
3354			intel_pt_calc_tma(decoder);
3355			break;
3356
3357		case INTEL_PT_CYC:
3358			intel_pt_calc_cyc_timestamp(decoder);
3359			break;
3360
3361		case INTEL_PT_CBR:
3362			intel_pt_calc_cbr(decoder);
3363			if (decoder->cbr != decoder->cbr_seen) {
3364				decoder->state.type = 0;
3365				return 0;
3366			}
3367			break;
3368
3369		case INTEL_PT_MODE_EXEC:
3370			intel_pt_mode_exec(decoder);
3371			err = intel_pt_get_next_packet(decoder);
3372			if (err)
3373				return err;
3374			if (decoder->packet.type == INTEL_PT_FUP) {
3375				decoder->set_fup_mode_exec = true;
3376				no_tip = true;
3377			}
3378			goto next;
3379
3380		case INTEL_PT_MODE_TSX:
3381			/* MODE_TSX need not be followed by FUP */
3382			if (!decoder->pge || decoder->in_psb) {
3383				intel_pt_update_in_tx(decoder);
3384				break;
3385			}
3386			err = intel_pt_mode_tsx(decoder, &no_tip);
3387			if (err)
3388				return err;
3389			goto next;
3390
3391		case INTEL_PT_BAD: /* Does not happen */
3392			return intel_pt_bug(decoder);
3393
3394		case INTEL_PT_PSBEND:
3395		case INTEL_PT_VMCS:
3396		case INTEL_PT_MNT:
3397		case INTEL_PT_PAD:
3398			break;
3399
3400		case INTEL_PT_PTWRITE_IP:
3401			decoder->fup_ptw_payload = decoder->packet.payload;
3402			err = intel_pt_get_next_packet(decoder);
3403			if (err)
3404				return err;
3405			if (decoder->packet.type == INTEL_PT_FUP) {
3406				decoder->set_fup_ptw = true;
3407				no_tip = true;
3408			} else {
3409				intel_pt_log_at("ERROR: Missing FUP after PTWRITE",
3410						decoder->pos);
3411			}
3412			goto next;
3413
3414		case INTEL_PT_PTWRITE:
3415			decoder->state.type = INTEL_PT_PTW;
3416			decoder->state.from_ip = decoder->ip;
3417			decoder->state.to_ip = 0;
3418			decoder->state.ptw_payload = decoder->packet.payload;
3419			return 0;
3420
3421		case INTEL_PT_MWAIT:
3422			decoder->fup_mwait_payload = decoder->packet.payload;
3423			decoder->set_fup_mwait = true;
3424			break;
3425
3426		case INTEL_PT_PWRE:
3427			if (decoder->set_fup_mwait) {
3428				decoder->fup_pwre_payload =
3429							decoder->packet.payload;
3430				decoder->set_fup_pwre = true;
3431				break;
3432			}
3433			decoder->state.type = INTEL_PT_PWR_ENTRY;
3434			decoder->state.from_ip = decoder->ip;
3435			decoder->state.to_ip = 0;
3436			decoder->state.pwrx_payload = decoder->packet.payload;
3437			return 0;
3438
3439		case INTEL_PT_EXSTOP_IP:
3440			err = intel_pt_get_next_packet(decoder);
3441			if (err)
3442				return err;
3443			if (decoder->packet.type == INTEL_PT_FUP) {
3444				decoder->set_fup_exstop = true;
3445				no_tip = true;
3446			} else {
3447				intel_pt_log_at("ERROR: Missing FUP after EXSTOP",
3448						decoder->pos);
3449			}
3450			goto next;
3451
3452		case INTEL_PT_EXSTOP:
3453			decoder->state.type = INTEL_PT_EX_STOP;
3454			decoder->state.from_ip = decoder->ip;
3455			decoder->state.to_ip = 0;
3456			return 0;
3457
3458		case INTEL_PT_PWRX:
3459			decoder->state.type = INTEL_PT_PWR_EXIT;
3460			decoder->state.from_ip = decoder->ip;
3461			decoder->state.to_ip = 0;
3462			decoder->state.pwrx_payload = decoder->packet.payload;
3463			return 0;
3464
3465		case INTEL_PT_BBP:
3466			intel_pt_bbp(decoder);
3467			break;
3468
3469		case INTEL_PT_BIP:
3470			intel_pt_bip(decoder);
3471			break;
3472
3473		case INTEL_PT_BEP:
3474			decoder->state.type = INTEL_PT_BLK_ITEMS;
3475			decoder->state.from_ip = decoder->ip;
3476			decoder->state.to_ip = 0;
3477			return 0;
3478
3479		case INTEL_PT_BEP_IP:
3480			err = intel_pt_get_next_packet(decoder);
3481			if (err)
3482				return err;
3483			if (decoder->packet.type == INTEL_PT_FUP) {
3484				decoder->set_fup_bep = true;
3485				no_tip = true;
3486			} else {
3487				intel_pt_log_at("ERROR: Missing FUP after BEP",
3488						decoder->pos);
3489			}
3490			goto next;
3491
3492		case INTEL_PT_CFE:
3493			decoder->fup_cfe_pkt = decoder->packet;
3494			decoder->set_fup_cfe = true;
3495			if (!decoder->pge) {
3496				intel_pt_fup_event(decoder, true);
3497				return 0;
3498			}
3499			break;
3500
3501		case INTEL_PT_CFE_IP:
3502			decoder->fup_cfe_pkt = decoder->packet;
3503			err = intel_pt_get_next_packet(decoder);
3504			if (err)
3505				return err;
3506			if (decoder->packet.type == INTEL_PT_FUP) {
3507				decoder->set_fup_cfe_ip = true;
3508				no_tip = true;
3509			} else {
3510				intel_pt_log_at("ERROR: Missing FUP after CFE",
3511						decoder->pos);
3512			}
3513			goto next;
3514
3515		case INTEL_PT_EVD:
3516			err = intel_pt_evd(decoder);
3517			if (err)
3518				return err;
3519			break;
3520
3521		default:
3522			return intel_pt_bug(decoder);
3523		}
3524	}
3525}
3526
3527static inline bool intel_pt_have_ip(struct intel_pt_decoder *decoder)
3528{
3529	return decoder->packet.count &&
3530	       (decoder->have_last_ip || decoder->packet.count == 3 ||
3531		decoder->packet.count == 6);
3532}
3533
3534/* Walk PSB+ packets to get in sync. */
3535static int intel_pt_walk_psb(struct intel_pt_decoder *decoder)
3536{
3537	int err;
3538
3539	decoder->in_psb = true;
3540
3541	while (1) {
3542		err = intel_pt_get_next_packet(decoder);
3543		if (err)
3544			goto out;
3545
3546		switch (decoder->packet.type) {
3547		case INTEL_PT_TIP_PGD:
3548			decoder->continuous_period = false;
3549			fallthrough;
3550		case INTEL_PT_TIP_PGE:
3551		case INTEL_PT_TIP:
3552		case INTEL_PT_PTWRITE:
3553		case INTEL_PT_PTWRITE_IP:
3554		case INTEL_PT_EXSTOP:
3555		case INTEL_PT_EXSTOP_IP:
3556		case INTEL_PT_MWAIT:
3557		case INTEL_PT_PWRE:
3558		case INTEL_PT_PWRX:
3559		case INTEL_PT_BBP:
3560		case INTEL_PT_BIP:
3561		case INTEL_PT_BEP:
3562		case INTEL_PT_BEP_IP:
3563		case INTEL_PT_CFE:
3564		case INTEL_PT_CFE_IP:
3565		case INTEL_PT_EVD:
3566			intel_pt_log("ERROR: Unexpected packet\n");
3567			err = -ENOENT;
3568			goto out;
3569
3570		case INTEL_PT_FUP:
3571			decoder->pge = true;
3572			if (intel_pt_have_ip(decoder)) {
3573				uint64_t current_ip = decoder->ip;
3574
3575				intel_pt_set_ip(decoder);
3576				decoder->psb_ip = decoder->ip;
3577				if (current_ip)
3578					intel_pt_log_to("Setting IP",
3579							decoder->ip);
3580			}
3581			break;
3582
3583		case INTEL_PT_MTC:
3584			intel_pt_calc_mtc_timestamp(decoder);
3585			break;
3586
3587		case INTEL_PT_TSC:
3588			intel_pt_calc_tsc_timestamp(decoder);
3589			break;
3590
3591		case INTEL_PT_TMA:
3592			intel_pt_calc_tma(decoder);
3593			break;
3594
3595		case INTEL_PT_CYC:
3596			intel_pt_calc_cyc_timestamp(decoder);
3597			break;
3598
3599		case INTEL_PT_CBR:
3600			intel_pt_calc_cbr(decoder);
3601			break;
3602
3603		case INTEL_PT_PIP:
3604			intel_pt_set_pip(decoder);
3605			break;
3606
3607		case INTEL_PT_MODE_EXEC:
3608			intel_pt_mode_exec_status(decoder);
3609			break;
3610
3611		case INTEL_PT_MODE_TSX:
3612			intel_pt_update_in_tx(decoder);
3613			break;
3614
3615		case INTEL_PT_TRACESTOP:
3616			decoder->pge = false;
3617			decoder->continuous_period = false;
3618			intel_pt_clear_tx_flags(decoder);
3619			fallthrough;
3620
3621		case INTEL_PT_TNT:
3622			decoder->have_tma = false;
3623			intel_pt_log("ERROR: Unexpected packet\n");
3624			if (decoder->ip)
3625				decoder->pkt_state = INTEL_PT_STATE_ERR4;
3626			else
3627				decoder->pkt_state = INTEL_PT_STATE_ERR3;
3628			err = -ENOENT;
3629			goto out;
3630
3631		case INTEL_PT_BAD: /* Does not happen */
3632			err = intel_pt_bug(decoder);
3633			goto out;
3634
3635		case INTEL_PT_OVF:
3636			err = intel_pt_overflow(decoder);
3637			goto out;
3638
3639		case INTEL_PT_PSBEND:
3640			err = 0;
3641			goto out;
3642
3643		case INTEL_PT_PSB:
3644		case INTEL_PT_VMCS:
3645		case INTEL_PT_MNT:
3646		case INTEL_PT_PAD:
3647		default:
3648			break;
3649		}
3650	}
3651out:
3652	decoder->in_psb = false;
3653
3654	return err;
3655}
3656
3657static int intel_pt_walk_to_ip(struct intel_pt_decoder *decoder)
3658{
3659	int err;
3660
3661	while (1) {
3662		err = intel_pt_get_next_packet(decoder);
3663		if (err)
3664			return err;
3665
3666		switch (decoder->packet.type) {
3667		case INTEL_PT_TIP_PGD:
3668			decoder->continuous_period = false;
3669			decoder->pge = false;
3670			if (intel_pt_have_ip(decoder))
3671				intel_pt_set_ip(decoder);
3672			if (!decoder->ip)
3673				break;
3674			decoder->state.type |= INTEL_PT_TRACE_END;
3675			return 0;
3676
3677		case INTEL_PT_TIP_PGE:
3678			decoder->pge = true;
3679			intel_pt_mtc_cyc_cnt_pge(decoder);
3680			if (intel_pt_have_ip(decoder))
3681				intel_pt_set_ip(decoder);
3682			if (!decoder->ip)
3683				break;
3684			decoder->state.type |= INTEL_PT_TRACE_BEGIN;
3685			return 0;
3686
3687		case INTEL_PT_TIP:
3688			decoder->pge = true;
3689			if (intel_pt_have_ip(decoder))
3690				intel_pt_set_ip(decoder);
3691			if (!decoder->ip)
3692				break;
3693			return 0;
3694
3695		case INTEL_PT_FUP:
3696			if (intel_pt_have_ip(decoder))
3697				intel_pt_set_ip(decoder);
3698			if (decoder->ip)
3699				return 0;
3700			break;
3701
3702		case INTEL_PT_MTC:
3703			intel_pt_calc_mtc_timestamp(decoder);
3704			break;
3705
3706		case INTEL_PT_TSC:
3707			intel_pt_calc_tsc_timestamp(decoder);
3708			break;
3709
3710		case INTEL_PT_TMA:
3711			intel_pt_calc_tma(decoder);
3712			break;
3713
3714		case INTEL_PT_CYC:
3715			intel_pt_calc_cyc_timestamp(decoder);
3716			break;
3717
3718		case INTEL_PT_CBR:
3719			intel_pt_calc_cbr(decoder);
3720			break;
3721
3722		case INTEL_PT_PIP:
3723			intel_pt_set_pip(decoder);
3724			break;
3725
3726		case INTEL_PT_MODE_EXEC:
3727			intel_pt_mode_exec_status(decoder);
3728			break;
3729
3730		case INTEL_PT_MODE_TSX:
3731			intel_pt_update_in_tx(decoder);
3732			break;
3733
3734		case INTEL_PT_OVF:
3735			return intel_pt_overflow(decoder);
3736
3737		case INTEL_PT_BAD: /* Does not happen */
3738			return intel_pt_bug(decoder);
3739
3740		case INTEL_PT_TRACESTOP:
3741			decoder->pge = false;
3742			decoder->continuous_period = false;
3743			intel_pt_clear_tx_flags(decoder);
3744			decoder->have_tma = false;
3745			break;
3746
3747		case INTEL_PT_PSB:
3748			decoder->state.psb_offset = decoder->pos;
3749			decoder->psb_ip = 0;
3750			decoder->last_ip = 0;
3751			decoder->have_last_ip = true;
3752			intel_pt_clear_stack(&decoder->stack);
3753			err = intel_pt_walk_psb(decoder);
3754			if (err)
3755				return err;
3756			decoder->state.type = INTEL_PT_PSB_EVT;
3757			decoder->state.from_ip = decoder->psb_ip;
3758			decoder->state.to_ip = 0;
3759			return 0;
 
 
3760
3761		case INTEL_PT_TNT:
3762		case INTEL_PT_PSBEND:
3763		case INTEL_PT_VMCS:
3764		case INTEL_PT_MNT:
3765		case INTEL_PT_PAD:
3766		case INTEL_PT_PTWRITE:
3767		case INTEL_PT_PTWRITE_IP:
3768		case INTEL_PT_EXSTOP:
3769		case INTEL_PT_EXSTOP_IP:
3770		case INTEL_PT_MWAIT:
3771		case INTEL_PT_PWRE:
3772		case INTEL_PT_PWRX:
3773		case INTEL_PT_BBP:
3774		case INTEL_PT_BIP:
3775		case INTEL_PT_BEP:
3776		case INTEL_PT_BEP_IP:
3777		case INTEL_PT_CFE:
3778		case INTEL_PT_CFE_IP:
3779		case INTEL_PT_EVD:
3780		default:
3781			break;
3782		}
3783	}
3784}
3785
3786static int intel_pt_sync_ip(struct intel_pt_decoder *decoder)
3787{
3788	int err;
3789
3790	intel_pt_clear_fup_event(decoder);
3791	decoder->overflow = false;
 
 
 
 
3792
3793	if (!decoder->branch_enable) {
3794		decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
 
3795		decoder->state.type = 0; /* Do not have a sample */
3796		return 0;
3797	}
3798
3799	intel_pt_log("Scanning for full IP\n");
3800	err = intel_pt_walk_to_ip(decoder);
3801	if (err || ((decoder->state.type & INTEL_PT_PSB_EVT) && !decoder->ip))
3802		return err;
3803
3804	/* In hop mode, resample to get the to_ip as an "instruction" sample */
3805	if (decoder->hop)
3806		decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
3807	else
3808		decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
 
3809
3810	decoder->state.from_ip = 0;
3811	decoder->state.to_ip = decoder->ip;
3812	intel_pt_log_to("Setting IP", decoder->ip);
3813
3814	return 0;
3815}
3816
3817static int intel_pt_part_psb(struct intel_pt_decoder *decoder)
3818{
3819	const unsigned char *end = decoder->buf + decoder->len;
3820	size_t i;
3821
3822	for (i = INTEL_PT_PSB_LEN - 1; i; i--) {
3823		if (i > decoder->len)
3824			continue;
3825		if (!memcmp(end - i, INTEL_PT_PSB_STR, i))
3826			return i;
3827	}
3828	return 0;
3829}
3830
3831static int intel_pt_rest_psb(struct intel_pt_decoder *decoder, int part_psb)
3832{
3833	size_t rest_psb = INTEL_PT_PSB_LEN - part_psb;
3834	const char *psb = INTEL_PT_PSB_STR;
3835
3836	if (rest_psb > decoder->len ||
3837	    memcmp(decoder->buf, psb + part_psb, rest_psb))
3838		return 0;
3839
3840	return rest_psb;
3841}
3842
3843static int intel_pt_get_split_psb(struct intel_pt_decoder *decoder,
3844				  int part_psb)
3845{
3846	int rest_psb, ret;
3847
3848	decoder->pos += decoder->len;
3849	decoder->len = 0;
3850
3851	ret = intel_pt_get_next_data(decoder, false);
3852	if (ret)
3853		return ret;
3854
3855	rest_psb = intel_pt_rest_psb(decoder, part_psb);
3856	if (!rest_psb)
3857		return 0;
3858
3859	decoder->pos -= part_psb;
3860	decoder->next_buf = decoder->buf + rest_psb;
3861	decoder->next_len = decoder->len - rest_psb;
3862	memcpy(decoder->temp_buf, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
3863	decoder->buf = decoder->temp_buf;
3864	decoder->len = INTEL_PT_PSB_LEN;
3865
3866	return 0;
3867}
3868
3869static int intel_pt_scan_for_psb(struct intel_pt_decoder *decoder)
3870{
3871	unsigned char *next;
3872	int ret;
3873
3874	intel_pt_log("Scanning for PSB\n");
3875	while (1) {
3876		if (!decoder->len) {
3877			ret = intel_pt_get_next_data(decoder, false);
3878			if (ret)
3879				return ret;
3880		}
3881
3882		next = memmem(decoder->buf, decoder->len, INTEL_PT_PSB_STR,
3883			      INTEL_PT_PSB_LEN);
3884		if (!next) {
3885			int part_psb;
3886
3887			part_psb = intel_pt_part_psb(decoder);
3888			if (part_psb) {
3889				ret = intel_pt_get_split_psb(decoder, part_psb);
3890				if (ret)
3891					return ret;
3892			} else {
3893				decoder->pos += decoder->len;
3894				decoder->len = 0;
3895			}
3896			continue;
3897		}
3898
3899		decoder->pkt_step = next - decoder->buf;
3900		return intel_pt_get_next_packet(decoder);
3901	}
3902}
3903
3904static int intel_pt_sync(struct intel_pt_decoder *decoder)
3905{
3906	int err;
3907
3908	decoder->pge = false;
3909	decoder->continuous_period = false;
3910	decoder->have_last_ip = false;
3911	decoder->last_ip = 0;
3912	decoder->psb_ip = 0;
3913	decoder->ip = 0;
3914	intel_pt_clear_stack(&decoder->stack);
3915
 
3916	err = intel_pt_scan_for_psb(decoder);
3917	if (err)
3918		return err;
3919
3920	if (decoder->vm_time_correlation) {
3921		decoder->in_psb = true;
3922		if (!decoder->timestamp)
3923			decoder->timestamp = 1;
3924		decoder->state.type = 0;
3925		decoder->pkt_state = INTEL_PT_STATE_VM_TIME_CORRELATION;
3926		return 0;
3927	}
3928
3929	decoder->have_last_ip = true;
3930	decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
3931
3932	err = intel_pt_walk_psb(decoder);
3933	if (err)
3934		return err;
3935
3936	decoder->state.type = INTEL_PT_PSB_EVT; /* Only PSB sample */
3937	decoder->state.from_ip = decoder->psb_ip;
3938	decoder->state.to_ip = 0;
3939
3940	if (decoder->ip) {
 
3941		/*
3942		 * In hop mode, resample to get the PSB FUP ip as an
3943		 * "instruction" sample.
3944		 */
3945		if (decoder->hop)
3946			decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
3947		else
3948			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
 
 
 
 
 
 
 
 
3949	}
3950
3951	return 0;
3952}
3953
3954static uint64_t intel_pt_est_timestamp(struct intel_pt_decoder *decoder)
3955{
3956	uint64_t est = decoder->sample_insn_cnt << 1;
3957
3958	if (!decoder->cbr || !decoder->max_non_turbo_ratio)
3959		goto out;
3960
3961	est *= decoder->max_non_turbo_ratio;
3962	est /= decoder->cbr;
3963out:
3964	return decoder->sample_timestamp + est;
3965}
3966
3967const struct intel_pt_state *intel_pt_decode(struct intel_pt_decoder *decoder)
3968{
3969	int err;
3970
3971	do {
3972		decoder->state.type = INTEL_PT_BRANCH;
3973		decoder->state.flags = 0;
3974
3975		switch (decoder->pkt_state) {
3976		case INTEL_PT_STATE_NO_PSB:
3977			err = intel_pt_sync(decoder);
3978			break;
3979		case INTEL_PT_STATE_NO_IP:
3980			decoder->have_last_ip = false;
3981			decoder->last_ip = 0;
3982			decoder->ip = 0;
3983			fallthrough;
3984		case INTEL_PT_STATE_ERR_RESYNC:
3985			err = intel_pt_sync_ip(decoder);
3986			break;
3987		case INTEL_PT_STATE_IN_SYNC:
3988			err = intel_pt_walk_trace(decoder);
3989			break;
3990		case INTEL_PT_STATE_TNT:
3991		case INTEL_PT_STATE_TNT_CONT:
3992			err = intel_pt_walk_tnt(decoder);
3993			if (err == -EAGAIN)
3994				err = intel_pt_walk_trace(decoder);
3995			break;
3996		case INTEL_PT_STATE_TIP:
3997		case INTEL_PT_STATE_TIP_PGD:
3998			err = intel_pt_walk_tip(decoder);
3999			break;
4000		case INTEL_PT_STATE_FUP:
4001			err = intel_pt_walk_fup(decoder);
4002			if (err == -EAGAIN)
4003				err = intel_pt_walk_fup_tip(decoder);
4004			break;
4005		case INTEL_PT_STATE_FUP_NO_TIP:
4006			err = intel_pt_walk_fup(decoder);
4007			if (err == -EAGAIN)
4008				err = intel_pt_walk_trace(decoder);
4009			break;
4010		case INTEL_PT_STATE_FUP_IN_PSB:
4011			err = intel_pt_fup_in_psb(decoder);
4012			break;
4013		case INTEL_PT_STATE_RESAMPLE:
4014			err = intel_pt_resample(decoder);
4015			break;
4016		case INTEL_PT_STATE_VM_TIME_CORRELATION:
4017			err = intel_pt_vm_time_correlation(decoder);
4018			break;
4019		default:
4020			err = intel_pt_bug(decoder);
4021			break;
4022		}
4023	} while (err == -ENOLINK);
4024
4025	if (err) {
4026		decoder->state.err = intel_pt_ext_err(err);
4027		if (err != -EOVERFLOW)
4028			decoder->state.from_ip = decoder->ip;
4029		intel_pt_update_sample_time(decoder);
4030		decoder->sample_tot_cyc_cnt = decoder->tot_cyc_cnt;
4031		intel_pt_set_nr(decoder);
4032	} else {
4033		decoder->state.err = 0;
4034		if (decoder->cbr != decoder->cbr_seen) {
4035			decoder->cbr_seen = decoder->cbr;
4036			if (!decoder->state.type) {
4037				decoder->state.from_ip = decoder->ip;
4038				decoder->state.to_ip = 0;
4039			}
4040			decoder->state.type |= INTEL_PT_CBR_CHG;
4041			decoder->state.cbr_payload = decoder->cbr_payload;
4042			decoder->state.cbr = decoder->cbr;
4043		}
4044		if (intel_pt_sample_time(decoder->pkt_state)) {
4045			intel_pt_update_sample_time(decoder);
4046			if (decoder->sample_cyc) {
4047				decoder->sample_tot_cyc_cnt = decoder->tot_cyc_cnt;
4048				decoder->state.flags |= INTEL_PT_SAMPLE_IPC;
4049				decoder->sample_cyc = false;
4050			}
4051		}
4052		/*
4053		 * When using only TSC/MTC to compute cycles, IPC can be
4054		 * sampled as soon as the cycle count changes.
4055		 */
4056		if (!decoder->have_cyc)
4057			decoder->state.flags |= INTEL_PT_SAMPLE_IPC;
4058	}
4059
4060	 /* Let PSB event always have TSC timestamp */
4061	if ((decoder->state.type & INTEL_PT_PSB_EVT) && decoder->tsc_timestamp)
4062		decoder->sample_timestamp = decoder->tsc_timestamp;
4063
4064	decoder->state.from_nr = decoder->nr;
4065	decoder->state.to_nr = decoder->next_nr;
4066	decoder->nr = decoder->next_nr;
4067
4068	decoder->state.timestamp = decoder->sample_timestamp;
4069	decoder->state.est_timestamp = intel_pt_est_timestamp(decoder);
 
4070	decoder->state.tot_insn_cnt = decoder->tot_insn_cnt;
4071	decoder->state.tot_cyc_cnt = decoder->sample_tot_cyc_cnt;
4072
4073	return &decoder->state;
4074}
4075
4076/**
4077 * intel_pt_next_psb - move buffer pointer to the start of the next PSB packet.
4078 * @buf: pointer to buffer pointer
4079 * @len: size of buffer
4080 *
4081 * Updates the buffer pointer to point to the start of the next PSB packet if
4082 * there is one, otherwise the buffer pointer is unchanged.  If @buf is updated,
4083 * @len is adjusted accordingly.
4084 *
4085 * Return: %true if a PSB packet is found, %false otherwise.
4086 */
4087static bool intel_pt_next_psb(unsigned char **buf, size_t *len)
4088{
4089	unsigned char *next;
4090
4091	next = memmem(*buf, *len, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
4092	if (next) {
4093		*len -= next - *buf;
4094		*buf = next;
4095		return true;
4096	}
4097	return false;
4098}
4099
4100/**
4101 * intel_pt_step_psb - move buffer pointer to the start of the following PSB
4102 *                     packet.
4103 * @buf: pointer to buffer pointer
4104 * @len: size of buffer
4105 *
4106 * Updates the buffer pointer to point to the start of the following PSB packet
4107 * (skipping the PSB at @buf itself) if there is one, otherwise the buffer
4108 * pointer is unchanged.  If @buf is updated, @len is adjusted accordingly.
4109 *
4110 * Return: %true if a PSB packet is found, %false otherwise.
4111 */
4112static bool intel_pt_step_psb(unsigned char **buf, size_t *len)
4113{
4114	unsigned char *next;
4115
4116	if (!*len)
4117		return false;
4118
4119	next = memmem(*buf + 1, *len - 1, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
4120	if (next) {
4121		*len -= next - *buf;
4122		*buf = next;
4123		return true;
4124	}
4125	return false;
4126}
4127
4128/**
4129 * intel_pt_last_psb - find the last PSB packet in a buffer.
4130 * @buf: buffer
4131 * @len: size of buffer
4132 *
4133 * This function finds the last PSB in a buffer.
4134 *
4135 * Return: A pointer to the last PSB in @buf if found, %NULL otherwise.
4136 */
4137static unsigned char *intel_pt_last_psb(unsigned char *buf, size_t len)
4138{
4139	const char *n = INTEL_PT_PSB_STR;
4140	unsigned char *p;
4141	size_t k;
4142
4143	if (len < INTEL_PT_PSB_LEN)
4144		return NULL;
4145
4146	k = len - INTEL_PT_PSB_LEN + 1;
4147	while (1) {
4148		p = memrchr(buf, n[0], k);
4149		if (!p)
4150			return NULL;
4151		if (!memcmp(p + 1, n + 1, INTEL_PT_PSB_LEN - 1))
4152			return p;
4153		k = p - buf;
4154		if (!k)
4155			return NULL;
4156	}
4157}
4158
4159/**
4160 * intel_pt_next_tsc - find and return next TSC.
4161 * @buf: buffer
4162 * @len: size of buffer
4163 * @tsc: TSC value returned
4164 * @rem: returns remaining size when TSC is found
4165 *
4166 * Find a TSC packet in @buf and return the TSC value.  This function assumes
4167 * that @buf starts at a PSB and that PSB+ will contain TSC and so stops if a
4168 * PSBEND packet is found.
4169 *
4170 * Return: %true if TSC is found, false otherwise.
4171 */
4172static bool intel_pt_next_tsc(unsigned char *buf, size_t len, uint64_t *tsc,
4173			      size_t *rem)
4174{
4175	enum intel_pt_pkt_ctx ctx = INTEL_PT_NO_CTX;
4176	struct intel_pt_pkt packet;
4177	int ret;
4178
4179	while (len) {
4180		ret = intel_pt_get_packet(buf, len, &packet, &ctx);
4181		if (ret <= 0)
4182			return false;
4183		if (packet.type == INTEL_PT_TSC) {
4184			*tsc = packet.payload;
4185			*rem = len;
4186			return true;
4187		}
4188		if (packet.type == INTEL_PT_PSBEND)
4189			return false;
4190		buf += ret;
4191		len -= ret;
4192	}
4193	return false;
4194}
4195
4196/**
4197 * intel_pt_tsc_cmp - compare 7-byte TSCs.
4198 * @tsc1: first TSC to compare
4199 * @tsc2: second TSC to compare
4200 *
4201 * This function compares 7-byte TSC values allowing for the possibility that
4202 * TSC wrapped around.  Generally it is not possible to know if TSC has wrapped
4203 * around so for that purpose this function assumes the absolute difference is
4204 * less than half the maximum difference.
4205 *
4206 * Return: %-1 if @tsc1 is before @tsc2, %0 if @tsc1 == @tsc2, %1 if @tsc1 is
4207 * after @tsc2.
4208 */
4209static int intel_pt_tsc_cmp(uint64_t tsc1, uint64_t tsc2)
4210{
4211	const uint64_t halfway = (1ULL << 55);
4212
4213	if (tsc1 == tsc2)
4214		return 0;
4215
4216	if (tsc1 < tsc2) {
4217		if (tsc2 - tsc1 < halfway)
4218			return -1;
4219		else
4220			return 1;
4221	} else {
4222		if (tsc1 - tsc2 < halfway)
4223			return 1;
4224		else
4225			return -1;
4226	}
4227}
4228
4229#define MAX_PADDING (PERF_AUXTRACE_RECORD_ALIGNMENT - 1)
4230
4231/**
4232 * adj_for_padding - adjust overlap to account for padding.
4233 * @buf_b: second buffer
4234 * @buf_a: first buffer
4235 * @len_a: size of first buffer
4236 *
4237 * @buf_a might have up to 7 bytes of padding appended. Adjust the overlap
4238 * accordingly.
4239 *
4240 * Return: A pointer into @buf_b from where non-overlapped data starts
4241 */
4242static unsigned char *adj_for_padding(unsigned char *buf_b,
4243				      unsigned char *buf_a, size_t len_a)
4244{
4245	unsigned char *p = buf_b - MAX_PADDING;
4246	unsigned char *q = buf_a + len_a - MAX_PADDING;
4247	int i;
4248
4249	for (i = MAX_PADDING; i; i--, p++, q++) {
4250		if (*p != *q)
4251			break;
4252	}
4253
4254	return p;
4255}
4256
4257/**
4258 * intel_pt_find_overlap_tsc - determine start of non-overlapped trace data
4259 *                             using TSC.
4260 * @buf_a: first buffer
4261 * @len_a: size of first buffer
4262 * @buf_b: second buffer
4263 * @len_b: size of second buffer
4264 * @consecutive: returns true if there is data in buf_b that is consecutive
4265 *               to buf_a
4266 * @ooo_tsc: out-of-order TSC due to VM TSC offset / scaling
4267 *
4268 * If the trace contains TSC we can look at the last TSC of @buf_a and the
4269 * first TSC of @buf_b in order to determine if the buffers overlap, and then
4270 * walk forward in @buf_b until a later TSC is found.  A precondition is that
4271 * @buf_a and @buf_b are positioned at a PSB.
4272 *
4273 * Return: A pointer into @buf_b from where non-overlapped data starts, or
4274 * @buf_b + @len_b if there is no non-overlapped data.
4275 */
4276static unsigned char *intel_pt_find_overlap_tsc(unsigned char *buf_a,
4277						size_t len_a,
4278						unsigned char *buf_b,
4279						size_t len_b, bool *consecutive,
4280						bool ooo_tsc)
4281{
4282	uint64_t tsc_a, tsc_b;
4283	unsigned char *p;
4284	size_t len, rem_a, rem_b;
4285
4286	p = intel_pt_last_psb(buf_a, len_a);
4287	if (!p)
4288		return buf_b; /* No PSB in buf_a => no overlap */
4289
4290	len = len_a - (p - buf_a);
4291	if (!intel_pt_next_tsc(p, len, &tsc_a, &rem_a)) {
4292		/* The last PSB+ in buf_a is incomplete, so go back one more */
4293		len_a -= len;
4294		p = intel_pt_last_psb(buf_a, len_a);
4295		if (!p)
4296			return buf_b; /* No full PSB+ => assume no overlap */
4297		len = len_a - (p - buf_a);
4298		if (!intel_pt_next_tsc(p, len, &tsc_a, &rem_a))
4299			return buf_b; /* No TSC in buf_a => assume no overlap */
4300	}
4301
4302	while (1) {
4303		/* Ignore PSB+ with no TSC */
4304		if (intel_pt_next_tsc(buf_b, len_b, &tsc_b, &rem_b)) {
4305			int cmp = intel_pt_tsc_cmp(tsc_a, tsc_b);
4306
4307			/* Same TSC, so buffers are consecutive */
4308			if (!cmp && rem_b >= rem_a) {
4309				unsigned char *start;
4310
4311				*consecutive = true;
4312				start = buf_b + len_b - (rem_b - rem_a);
4313				return adj_for_padding(start, buf_a, len_a);
4314			}
4315			if (cmp < 0 && !ooo_tsc)
4316				return buf_b; /* tsc_a < tsc_b => no overlap */
4317		}
4318
4319		if (!intel_pt_step_psb(&buf_b, &len_b))
4320			return buf_b + len_b; /* No PSB in buf_b => no data */
4321	}
4322}
4323
4324/**
4325 * intel_pt_find_overlap - determine start of non-overlapped trace data.
4326 * @buf_a: first buffer
4327 * @len_a: size of first buffer
4328 * @buf_b: second buffer
4329 * @len_b: size of second buffer
4330 * @have_tsc: can use TSC packets to detect overlap
4331 * @consecutive: returns true if there is data in buf_b that is consecutive
4332 *               to buf_a
4333 * @ooo_tsc: out-of-order TSC due to VM TSC offset / scaling
4334 *
4335 * When trace samples or snapshots are recorded there is the possibility that
4336 * the data overlaps.  Note that, for the purposes of decoding, data is only
4337 * useful if it begins with a PSB packet.
4338 *
4339 * Return: A pointer into @buf_b from where non-overlapped data starts, or
4340 * @buf_b + @len_b if there is no non-overlapped data.
4341 */
4342unsigned char *intel_pt_find_overlap(unsigned char *buf_a, size_t len_a,
4343				     unsigned char *buf_b, size_t len_b,
4344				     bool have_tsc, bool *consecutive,
4345				     bool ooo_tsc)
4346{
4347	unsigned char *found;
4348
4349	/* Buffer 'b' must start at PSB so throw away everything before that */
4350	if (!intel_pt_next_psb(&buf_b, &len_b))
4351		return buf_b + len_b; /* No PSB */
4352
4353	if (!intel_pt_next_psb(&buf_a, &len_a))
4354		return buf_b; /* No overlap */
4355
4356	if (have_tsc) {
4357		found = intel_pt_find_overlap_tsc(buf_a, len_a, buf_b, len_b,
4358						  consecutive, ooo_tsc);
4359		if (found)
4360			return found;
4361	}
4362
4363	/*
4364	 * Buffer 'b' cannot end within buffer 'a' so, for comparison purposes,
4365	 * we can ignore the first part of buffer 'a'.
4366	 */
4367	while (len_b < len_a) {
4368		if (!intel_pt_step_psb(&buf_a, &len_a))
4369			return buf_b; /* No overlap */
4370	}
4371
4372	/* Now len_b >= len_a */
4373	while (1) {
4374		/* Potential overlap so check the bytes */
4375		found = memmem(buf_a, len_a, buf_b, len_a);
4376		if (found) {
4377			*consecutive = true;
4378			return adj_for_padding(buf_b + len_a, buf_a, len_a);
4379		}
4380
4381		/* Try again at next PSB in buffer 'a' */
4382		if (!intel_pt_step_psb(&buf_a, &len_a))
4383			return buf_b; /* No overlap */
4384	}
4385}
4386
4387/**
4388 * struct fast_forward_data - data used by intel_pt_ff_cb().
4389 * @timestamp: timestamp to fast forward towards
4390 * @buf_timestamp: buffer timestamp of last buffer with trace data earlier than
4391 *                 the fast forward timestamp.
4392 */
4393struct fast_forward_data {
4394	uint64_t timestamp;
4395	uint64_t buf_timestamp;
4396};
4397
4398/**
4399 * intel_pt_ff_cb - fast forward lookahead callback.
4400 * @buffer: Intel PT trace buffer
4401 * @data: opaque pointer to fast forward data (struct fast_forward_data)
4402 *
4403 * Determine if @buffer trace is past the fast forward timestamp.
4404 *
4405 * Return: 1 (stop lookahead) if @buffer trace is past the fast forward
4406 *         timestamp, and 0 otherwise.
4407 */
4408static int intel_pt_ff_cb(struct intel_pt_buffer *buffer, void *data)
4409{
4410	struct fast_forward_data *d = data;
4411	unsigned char *buf;
4412	uint64_t tsc;
4413	size_t rem;
4414	size_t len;
4415
4416	buf = (unsigned char *)buffer->buf;
4417	len = buffer->len;
4418
4419	if (!intel_pt_next_psb(&buf, &len) ||
4420	    !intel_pt_next_tsc(buf, len, &tsc, &rem))
4421		return 0;
4422
4423	tsc = intel_pt_8b_tsc(tsc, buffer->ref_timestamp);
4424
4425	intel_pt_log("Buffer 1st timestamp " x64_fmt " ref timestamp " x64_fmt "\n",
4426		     tsc, buffer->ref_timestamp);
4427
4428	/*
4429	 * If the buffer contains a timestamp earlier that the fast forward
4430	 * timestamp, then record it, else stop.
4431	 */
4432	if (tsc < d->timestamp)
4433		d->buf_timestamp = buffer->ref_timestamp;
4434	else
4435		return 1;
4436
4437	return 0;
4438}
4439
4440/**
4441 * intel_pt_fast_forward - reposition decoder forwards.
4442 * @decoder: Intel PT decoder
4443 * @timestamp: timestamp to fast forward towards
4444 *
4445 * Reposition decoder at the last PSB with a timestamp earlier than @timestamp.
4446 *
4447 * Return: 0 on success or negative error code on failure.
4448 */
4449int intel_pt_fast_forward(struct intel_pt_decoder *decoder, uint64_t timestamp)
4450{
4451	struct fast_forward_data d = { .timestamp = timestamp };
4452	unsigned char *buf;
4453	size_t len;
4454	int err;
4455
4456	intel_pt_log("Fast forward towards timestamp " x64_fmt "\n", timestamp);
4457
4458	/* Find buffer timestamp of buffer to fast forward to */
4459	err = decoder->lookahead(decoder->data, intel_pt_ff_cb, &d);
4460	if (err < 0)
4461		return err;
4462
4463	/* Walk to buffer with same buffer timestamp */
4464	if (d.buf_timestamp) {
4465		do {
4466			decoder->pos += decoder->len;
4467			decoder->len = 0;
4468			err = intel_pt_get_next_data(decoder, true);
4469			/* -ENOLINK means non-consecutive trace */
4470			if (err && err != -ENOLINK)
4471				return err;
4472		} while (decoder->buf_timestamp != d.buf_timestamp);
4473	}
4474
4475	if (!decoder->buf)
4476		return 0;
4477
4478	buf = (unsigned char *)decoder->buf;
4479	len = decoder->len;
4480
4481	if (!intel_pt_next_psb(&buf, &len))
4482		return 0;
4483
4484	/*
4485	 * Walk PSBs while the PSB timestamp is less than the fast forward
4486	 * timestamp.
4487	 */
4488	do {
4489		uint64_t tsc;
4490		size_t rem;
4491
4492		if (!intel_pt_next_tsc(buf, len, &tsc, &rem))
4493			break;
4494		tsc = intel_pt_8b_tsc(tsc, decoder->buf_timestamp);
4495		/*
4496		 * A TSC packet can slip past MTC packets but, after fast
4497		 * forward, decoding starts at the TSC timestamp. That means
4498		 * the timestamps may not be exactly the same as the timestamps
4499		 * that would have been decoded without fast forward.
4500		 */
4501		if (tsc < timestamp) {
4502			intel_pt_log("Fast forward to next PSB timestamp " x64_fmt "\n", tsc);
4503			decoder->pos += decoder->len - len;
4504			decoder->buf = buf;
4505			decoder->len = len;
4506			intel_pt_reposition(decoder);
4507		} else {
4508			break;
4509		}
4510	} while (intel_pt_step_psb(&buf, &len));
4511
4512	return 0;
4513}
v5.9
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * intel_pt_decoder.c: Intel Processor Trace support
   4 * Copyright (c) 2013-2014, Intel Corporation.
   5 */
   6
   7#ifndef _GNU_SOURCE
   8#define _GNU_SOURCE
   9#endif
  10#include <stdlib.h>
  11#include <stdbool.h>
  12#include <string.h>
  13#include <errno.h>
  14#include <stdint.h>
  15#include <inttypes.h>
  16#include <linux/compiler.h>
  17#include <linux/string.h>
  18#include <linux/zalloc.h>
  19
  20#include "../auxtrace.h"
  21
  22#include "intel-pt-insn-decoder.h"
  23#include "intel-pt-pkt-decoder.h"
  24#include "intel-pt-decoder.h"
  25#include "intel-pt-log.h"
  26
 
 
 
 
 
 
 
  27#define INTEL_PT_BLK_SIZE 1024
  28
  29#define BIT63 (((uint64_t)1 << 63))
  30
 
 
 
 
  31#define INTEL_PT_RETURN 1
  32
  33/* Maximum number of loops with no packets consumed i.e. stuck in a loop */
  34#define INTEL_PT_MAX_LOOPS 10000
 
 
 
  35
  36struct intel_pt_blk {
  37	struct intel_pt_blk *prev;
  38	uint64_t ip[INTEL_PT_BLK_SIZE];
  39};
  40
  41struct intel_pt_stack {
  42	struct intel_pt_blk *blk;
  43	struct intel_pt_blk *spare;
  44	int pos;
  45};
  46
 
 
 
 
 
  47enum intel_pt_pkt_state {
  48	INTEL_PT_STATE_NO_PSB,
  49	INTEL_PT_STATE_NO_IP,
  50	INTEL_PT_STATE_ERR_RESYNC,
  51	INTEL_PT_STATE_IN_SYNC,
  52	INTEL_PT_STATE_TNT_CONT,
  53	INTEL_PT_STATE_TNT,
  54	INTEL_PT_STATE_TIP,
  55	INTEL_PT_STATE_TIP_PGD,
  56	INTEL_PT_STATE_FUP,
  57	INTEL_PT_STATE_FUP_NO_TIP,
 
  58	INTEL_PT_STATE_RESAMPLE,
 
  59};
  60
  61static inline bool intel_pt_sample_time(enum intel_pt_pkt_state pkt_state)
  62{
  63	switch (pkt_state) {
  64	case INTEL_PT_STATE_NO_PSB:
  65	case INTEL_PT_STATE_NO_IP:
  66	case INTEL_PT_STATE_ERR_RESYNC:
  67	case INTEL_PT_STATE_IN_SYNC:
  68	case INTEL_PT_STATE_TNT_CONT:
  69	case INTEL_PT_STATE_RESAMPLE:
 
  70		return true;
  71	case INTEL_PT_STATE_TNT:
  72	case INTEL_PT_STATE_TIP:
  73	case INTEL_PT_STATE_TIP_PGD:
  74	case INTEL_PT_STATE_FUP:
  75	case INTEL_PT_STATE_FUP_NO_TIP:
 
  76		return false;
  77	default:
  78		return true;
  79	};
  80}
  81
  82#ifdef INTEL_PT_STRICT
  83#define INTEL_PT_STATE_ERR1	INTEL_PT_STATE_NO_PSB
  84#define INTEL_PT_STATE_ERR2	INTEL_PT_STATE_NO_PSB
  85#define INTEL_PT_STATE_ERR3	INTEL_PT_STATE_NO_PSB
  86#define INTEL_PT_STATE_ERR4	INTEL_PT_STATE_NO_PSB
  87#else
  88#define INTEL_PT_STATE_ERR1	(decoder->pkt_state)
  89#define INTEL_PT_STATE_ERR2	INTEL_PT_STATE_NO_IP
  90#define INTEL_PT_STATE_ERR3	INTEL_PT_STATE_ERR_RESYNC
  91#define INTEL_PT_STATE_ERR4	INTEL_PT_STATE_IN_SYNC
  92#endif
  93
  94struct intel_pt_decoder {
  95	int (*get_trace)(struct intel_pt_buffer *buffer, void *data);
  96	int (*walk_insn)(struct intel_pt_insn *intel_pt_insn,
  97			 uint64_t *insn_cnt_ptr, uint64_t *ip, uint64_t to_ip,
  98			 uint64_t max_insn_cnt, void *data);
  99	bool (*pgd_ip)(uint64_t ip, void *data);
 100	int (*lookahead)(void *data, intel_pt_lookahead_cb_t cb, void *cb_data);
 
 101	void *data;
 102	struct intel_pt_state state;
 103	const unsigned char *buf;
 104	size_t len;
 105	bool return_compression;
 106	bool branch_enable;
 107	bool mtc_insn;
 108	bool pge;
 109	bool have_tma;
 110	bool have_cyc;
 111	bool fixup_last_mtc;
 112	bool have_last_ip;
 113	bool in_psb;
 114	bool hop;
 115	bool hop_psb_fup;
 116	bool leap;
 
 
 
 
 
 
 
 
 
 
 117	enum intel_pt_param_flags flags;
 118	uint64_t pos;
 119	uint64_t last_ip;
 120	uint64_t ip;
 121	uint64_t cr3;
 122	uint64_t timestamp;
 123	uint64_t tsc_timestamp;
 124	uint64_t ref_timestamp;
 125	uint64_t buf_timestamp;
 126	uint64_t sample_timestamp;
 127	uint64_t ret_addr;
 128	uint64_t ctc_timestamp;
 129	uint64_t ctc_delta;
 130	uint64_t cycle_cnt;
 131	uint64_t cyc_ref_timestamp;
 
 
 
 
 
 132	uint32_t last_mtc;
 133	uint32_t tsc_ctc_ratio_n;
 134	uint32_t tsc_ctc_ratio_d;
 135	uint32_t tsc_ctc_mult;
 136	uint32_t tsc_slip;
 137	uint32_t ctc_rem_mask;
 138	int mtc_shift;
 139	struct intel_pt_stack stack;
 140	enum intel_pt_pkt_state pkt_state;
 141	enum intel_pt_pkt_ctx pkt_ctx;
 142	enum intel_pt_pkt_ctx prev_pkt_ctx;
 143	enum intel_pt_blk_type blk_type;
 144	int blk_type_pos;
 145	struct intel_pt_pkt packet;
 146	struct intel_pt_pkt tnt;
 147	int pkt_step;
 148	int pkt_len;
 149	int last_packet_type;
 150	unsigned int cbr;
 151	unsigned int cbr_seen;
 152	unsigned int max_non_turbo_ratio;
 153	double max_non_turbo_ratio_fp;
 154	double cbr_cyc_to_tsc;
 155	double calc_cyc_to_tsc;
 156	bool have_calc_cyc_to_tsc;
 157	int exec_mode;
 158	unsigned int insn_bytes;
 159	uint64_t period;
 160	enum intel_pt_period_type period_type;
 161	uint64_t tot_insn_cnt;
 162	uint64_t period_insn_cnt;
 163	uint64_t period_mask;
 164	uint64_t period_ticks;
 165	uint64_t last_masked_timestamp;
 166	uint64_t tot_cyc_cnt;
 167	uint64_t sample_tot_cyc_cnt;
 168	uint64_t base_cyc_cnt;
 169	uint64_t cyc_cnt_timestamp;
 
 
 170	double tsc_to_cyc;
 171	bool continuous_period;
 172	bool overflow;
 173	bool set_fup_tx_flags;
 174	bool set_fup_ptw;
 175	bool set_fup_mwait;
 176	bool set_fup_pwre;
 177	bool set_fup_exstop;
 178	bool set_fup_bep;
 
 
 
 179	bool sample_cyc;
 180	unsigned int fup_tx_flags;
 181	unsigned int tx_flags;
 182	uint64_t fup_ptw_payload;
 183	uint64_t fup_mwait_payload;
 184	uint64_t fup_pwre_payload;
 185	uint64_t cbr_payload;
 186	uint64_t timestamp_insn_cnt;
 187	uint64_t sample_insn_cnt;
 188	uint64_t stuck_ip;
 
 
 189	int no_progress;
 190	int stuck_ip_prd;
 191	int stuck_ip_cnt;
 
 192	const unsigned char *next_buf;
 193	size_t next_len;
 194	unsigned char temp_buf[INTEL_PT_PKT_MAX_SZ];
 
 
 195};
 196
 197static uint64_t intel_pt_lower_power_of_2(uint64_t x)
 198{
 199	int i;
 200
 201	for (i = 0; x != 1; i++)
 202		x >>= 1;
 203
 204	return x << i;
 205}
 206
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 207static void intel_pt_setup_period(struct intel_pt_decoder *decoder)
 208{
 209	if (decoder->period_type == INTEL_PT_PERIOD_TICKS) {
 210		uint64_t period;
 211
 212		period = intel_pt_lower_power_of_2(decoder->period);
 213		decoder->period_mask  = ~(period - 1);
 214		decoder->period_ticks = period;
 215	}
 216}
 217
 218static uint64_t multdiv(uint64_t t, uint32_t n, uint32_t d)
 219{
 220	if (!d)
 221		return 0;
 222	return (t / d) * n + ((t % d) * n) / d;
 223}
 224
 225struct intel_pt_decoder *intel_pt_decoder_new(struct intel_pt_params *params)
 226{
 227	struct intel_pt_decoder *decoder;
 228
 229	if (!params->get_trace || !params->walk_insn)
 230		return NULL;
 231
 232	decoder = zalloc(sizeof(struct intel_pt_decoder));
 233	if (!decoder)
 234		return NULL;
 235
 236	decoder->get_trace          = params->get_trace;
 237	decoder->walk_insn          = params->walk_insn;
 238	decoder->pgd_ip             = params->pgd_ip;
 239	decoder->lookahead          = params->lookahead;
 
 240	decoder->data               = params->data;
 241	decoder->return_compression = params->return_compression;
 242	decoder->branch_enable      = params->branch_enable;
 243	decoder->hop                = params->quick >= 1;
 244	decoder->leap               = params->quick >= 2;
 
 
 
 
 
 245
 246	decoder->flags              = params->flags;
 247
 
 248	decoder->period             = params->period;
 249	decoder->period_type        = params->period_type;
 250
 251	decoder->max_non_turbo_ratio    = params->max_non_turbo_ratio;
 252	decoder->max_non_turbo_ratio_fp = params->max_non_turbo_ratio;
 253
 
 
 254	intel_pt_setup_period(decoder);
 255
 256	decoder->mtc_shift = params->mtc_period;
 257	decoder->ctc_rem_mask = (1 << decoder->mtc_shift) - 1;
 258
 259	decoder->tsc_ctc_ratio_n = params->tsc_ctc_ratio_n;
 260	decoder->tsc_ctc_ratio_d = params->tsc_ctc_ratio_d;
 261
 262	if (!decoder->tsc_ctc_ratio_n)
 263		decoder->tsc_ctc_ratio_d = 0;
 264
 265	if (decoder->tsc_ctc_ratio_d) {
 266		if (!(decoder->tsc_ctc_ratio_n % decoder->tsc_ctc_ratio_d))
 267			decoder->tsc_ctc_mult = decoder->tsc_ctc_ratio_n /
 268						decoder->tsc_ctc_ratio_d;
 269	}
 270
 271	/*
 272	 * A TSC packet can slip past MTC packets so that the timestamp appears
 273	 * to go backwards. One estimate is that can be up to about 40 CPU
 274	 * cycles, which is certainly less than 0x1000 TSC ticks, but accept
 275	 * slippage an order of magnitude more to be on the safe side.
 276	 */
 277	decoder->tsc_slip = 0x10000;
 278
 279	intel_pt_log("timestamp: mtc_shift %u\n", decoder->mtc_shift);
 280	intel_pt_log("timestamp: tsc_ctc_ratio_n %u\n", decoder->tsc_ctc_ratio_n);
 281	intel_pt_log("timestamp: tsc_ctc_ratio_d %u\n", decoder->tsc_ctc_ratio_d);
 282	intel_pt_log("timestamp: tsc_ctc_mult %u\n", decoder->tsc_ctc_mult);
 283	intel_pt_log("timestamp: tsc_slip %#x\n", decoder->tsc_slip);
 284
 285	if (decoder->hop)
 286		intel_pt_log("Hop mode: decoding FUP and TIPs, but not TNT\n");
 287
 288	return decoder;
 289}
 290
 
 
 
 
 
 
 291static void intel_pt_pop_blk(struct intel_pt_stack *stack)
 292{
 293	struct intel_pt_blk *blk = stack->blk;
 294
 295	stack->blk = blk->prev;
 296	if (!stack->spare)
 297		stack->spare = blk;
 298	else
 299		free(blk);
 300}
 301
 302static uint64_t intel_pt_pop(struct intel_pt_stack *stack)
 303{
 304	if (!stack->pos) {
 305		if (!stack->blk)
 306			return 0;
 307		intel_pt_pop_blk(stack);
 308		if (!stack->blk)
 309			return 0;
 310		stack->pos = INTEL_PT_BLK_SIZE;
 311	}
 312	return stack->blk->ip[--stack->pos];
 313}
 314
 315static int intel_pt_alloc_blk(struct intel_pt_stack *stack)
 316{
 317	struct intel_pt_blk *blk;
 318
 319	if (stack->spare) {
 320		blk = stack->spare;
 321		stack->spare = NULL;
 322	} else {
 323		blk = malloc(sizeof(struct intel_pt_blk));
 324		if (!blk)
 325			return -ENOMEM;
 326	}
 327
 328	blk->prev = stack->blk;
 329	stack->blk = blk;
 330	stack->pos = 0;
 331	return 0;
 332}
 333
 334static int intel_pt_push(struct intel_pt_stack *stack, uint64_t ip)
 335{
 336	int err;
 337
 338	if (!stack->blk || stack->pos == INTEL_PT_BLK_SIZE) {
 339		err = intel_pt_alloc_blk(stack);
 340		if (err)
 341			return err;
 342	}
 343
 344	stack->blk->ip[stack->pos++] = ip;
 345	return 0;
 346}
 347
 348static void intel_pt_clear_stack(struct intel_pt_stack *stack)
 349{
 350	while (stack->blk)
 351		intel_pt_pop_blk(stack);
 352	stack->pos = 0;
 353}
 354
 355static void intel_pt_free_stack(struct intel_pt_stack *stack)
 356{
 357	intel_pt_clear_stack(stack);
 358	zfree(&stack->blk);
 359	zfree(&stack->spare);
 360}
 361
 362void intel_pt_decoder_free(struct intel_pt_decoder *decoder)
 363{
 364	intel_pt_free_stack(&decoder->stack);
 365	free(decoder);
 366}
 367
 368static int intel_pt_ext_err(int code)
 369{
 370	switch (code) {
 371	case -ENOMEM:
 372		return INTEL_PT_ERR_NOMEM;
 373	case -ENOSYS:
 374		return INTEL_PT_ERR_INTERN;
 375	case -EBADMSG:
 376		return INTEL_PT_ERR_BADPKT;
 377	case -ENODATA:
 378		return INTEL_PT_ERR_NODATA;
 379	case -EILSEQ:
 380		return INTEL_PT_ERR_NOINSN;
 381	case -ENOENT:
 382		return INTEL_PT_ERR_MISMAT;
 383	case -EOVERFLOW:
 384		return INTEL_PT_ERR_OVR;
 385	case -ENOSPC:
 386		return INTEL_PT_ERR_LOST;
 387	case -ELOOP:
 388		return INTEL_PT_ERR_NELOOP;
 
 
 389	default:
 390		return INTEL_PT_ERR_UNK;
 391	}
 392}
 393
 394static const char *intel_pt_err_msgs[] = {
 395	[INTEL_PT_ERR_NOMEM]  = "Memory allocation failed",
 396	[INTEL_PT_ERR_INTERN] = "Internal error",
 397	[INTEL_PT_ERR_BADPKT] = "Bad packet",
 398	[INTEL_PT_ERR_NODATA] = "No more data",
 399	[INTEL_PT_ERR_NOINSN] = "Failed to get instruction",
 400	[INTEL_PT_ERR_MISMAT] = "Trace doesn't match instruction",
 401	[INTEL_PT_ERR_OVR]    = "Overflow packet",
 402	[INTEL_PT_ERR_LOST]   = "Lost trace data",
 403	[INTEL_PT_ERR_UNK]    = "Unknown error!",
 404	[INTEL_PT_ERR_NELOOP] = "Never-ending loop",
 
 405};
 406
 407int intel_pt__strerror(int code, char *buf, size_t buflen)
 408{
 409	if (code < 1 || code >= INTEL_PT_ERR_MAX)
 410		code = INTEL_PT_ERR_UNK;
 411	strlcpy(buf, intel_pt_err_msgs[code], buflen);
 412	return 0;
 413}
 414
 415static uint64_t intel_pt_calc_ip(const struct intel_pt_pkt *packet,
 416				 uint64_t last_ip)
 417{
 418	uint64_t ip;
 419
 420	switch (packet->count) {
 421	case 1:
 422		ip = (last_ip & (uint64_t)0xffffffffffff0000ULL) |
 423		     packet->payload;
 424		break;
 425	case 2:
 426		ip = (last_ip & (uint64_t)0xffffffff00000000ULL) |
 427		     packet->payload;
 428		break;
 429	case 3:
 430		ip = packet->payload;
 431		/* Sign-extend 6-byte ip */
 432		if (ip & (uint64_t)0x800000000000ULL)
 433			ip |= (uint64_t)0xffff000000000000ULL;
 434		break;
 435	case 4:
 436		ip = (last_ip & (uint64_t)0xffff000000000000ULL) |
 437		     packet->payload;
 438		break;
 439	case 6:
 440		ip = packet->payload;
 441		break;
 442	default:
 443		return 0;
 444	}
 445
 446	return ip;
 447}
 448
 449static inline void intel_pt_set_last_ip(struct intel_pt_decoder *decoder)
 450{
 451	decoder->last_ip = intel_pt_calc_ip(&decoder->packet, decoder->last_ip);
 452	decoder->have_last_ip = true;
 453}
 454
 455static inline void intel_pt_set_ip(struct intel_pt_decoder *decoder)
 456{
 457	intel_pt_set_last_ip(decoder);
 458	decoder->ip = decoder->last_ip;
 459}
 460
 461static void intel_pt_decoder_log_packet(struct intel_pt_decoder *decoder)
 462{
 463	intel_pt_log_packet(&decoder->packet, decoder->pkt_len, decoder->pos,
 464			    decoder->buf);
 465}
 466
 467static int intel_pt_bug(struct intel_pt_decoder *decoder)
 468{
 469	intel_pt_log("ERROR: Internal error\n");
 470	decoder->pkt_state = INTEL_PT_STATE_NO_PSB;
 471	return -ENOSYS;
 472}
 473
 474static inline void intel_pt_clear_tx_flags(struct intel_pt_decoder *decoder)
 475{
 476	decoder->tx_flags = 0;
 477}
 478
 479static inline void intel_pt_update_in_tx(struct intel_pt_decoder *decoder)
 480{
 481	decoder->tx_flags = decoder->packet.payload & INTEL_PT_IN_TX;
 482}
 483
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 484static int intel_pt_bad_packet(struct intel_pt_decoder *decoder)
 485{
 486	intel_pt_clear_tx_flags(decoder);
 487	decoder->have_tma = false;
 488	decoder->pkt_len = 1;
 489	decoder->pkt_step = 1;
 490	intel_pt_decoder_log_packet(decoder);
 491	if (decoder->pkt_state != INTEL_PT_STATE_NO_PSB) {
 492		intel_pt_log("ERROR: Bad packet\n");
 493		decoder->pkt_state = INTEL_PT_STATE_ERR1;
 494	}
 495	return -EBADMSG;
 496}
 497
 498static inline void intel_pt_update_sample_time(struct intel_pt_decoder *decoder)
 499{
 500	decoder->sample_timestamp = decoder->timestamp;
 501	decoder->sample_insn_cnt = decoder->timestamp_insn_cnt;
 
 502}
 503
 504static void intel_pt_reposition(struct intel_pt_decoder *decoder)
 505{
 506	decoder->ip = 0;
 507	decoder->pkt_state = INTEL_PT_STATE_NO_PSB;
 508	decoder->timestamp = 0;
 509	decoder->have_tma = false;
 510}
 511
 512static int intel_pt_get_data(struct intel_pt_decoder *decoder, bool reposition)
 513{
 514	struct intel_pt_buffer buffer = { .buf = 0, };
 515	int ret;
 516
 517	decoder->pkt_step = 0;
 518
 519	intel_pt_log("Getting more data\n");
 520	ret = decoder->get_trace(&buffer, decoder->data);
 521	if (ret)
 522		return ret;
 523	decoder->buf = buffer.buf;
 524	decoder->len = buffer.len;
 525	if (!decoder->len) {
 526		intel_pt_log("No more data\n");
 527		return -ENODATA;
 528	}
 529	decoder->buf_timestamp = buffer.ref_timestamp;
 530	if (!buffer.consecutive || reposition) {
 531		intel_pt_reposition(decoder);
 532		decoder->ref_timestamp = buffer.ref_timestamp;
 533		decoder->state.trace_nr = buffer.trace_nr;
 
 534		intel_pt_log("Reference timestamp 0x%" PRIx64 "\n",
 535			     decoder->ref_timestamp);
 536		return -ENOLINK;
 537	}
 538
 539	return 0;
 540}
 541
 542static int intel_pt_get_next_data(struct intel_pt_decoder *decoder,
 543				  bool reposition)
 544{
 545	if (!decoder->next_buf)
 546		return intel_pt_get_data(decoder, reposition);
 547
 548	decoder->buf = decoder->next_buf;
 549	decoder->len = decoder->next_len;
 550	decoder->next_buf = 0;
 551	decoder->next_len = 0;
 552	return 0;
 553}
 554
 555static int intel_pt_get_split_packet(struct intel_pt_decoder *decoder)
 556{
 557	unsigned char *buf = decoder->temp_buf;
 558	size_t old_len, len, n;
 559	int ret;
 560
 561	old_len = decoder->len;
 562	len = decoder->len;
 563	memcpy(buf, decoder->buf, len);
 564
 565	ret = intel_pt_get_data(decoder, false);
 566	if (ret) {
 567		decoder->pos += old_len;
 568		return ret < 0 ? ret : -EINVAL;
 569	}
 570
 571	n = INTEL_PT_PKT_MAX_SZ - len;
 572	if (n > decoder->len)
 573		n = decoder->len;
 574	memcpy(buf + len, decoder->buf, n);
 575	len += n;
 576
 577	decoder->prev_pkt_ctx = decoder->pkt_ctx;
 578	ret = intel_pt_get_packet(buf, len, &decoder->packet, &decoder->pkt_ctx);
 579	if (ret < (int)old_len) {
 580		decoder->next_buf = decoder->buf;
 581		decoder->next_len = decoder->len;
 582		decoder->buf = buf;
 583		decoder->len = old_len;
 584		return intel_pt_bad_packet(decoder);
 585	}
 586
 587	decoder->next_buf = decoder->buf + (ret - old_len);
 588	decoder->next_len = decoder->len - (ret - old_len);
 589
 590	decoder->buf = buf;
 591	decoder->len = ret;
 592
 593	return ret;
 594}
 595
 596struct intel_pt_pkt_info {
 597	struct intel_pt_decoder	  *decoder;
 598	struct intel_pt_pkt       packet;
 599	uint64_t                  pos;
 600	int                       pkt_len;
 601	int                       last_packet_type;
 602	void                      *data;
 603};
 604
 605typedef int (*intel_pt_pkt_cb_t)(struct intel_pt_pkt_info *pkt_info);
 606
 607/* Lookahead packets in current buffer */
 608static int intel_pt_pkt_lookahead(struct intel_pt_decoder *decoder,
 609				  intel_pt_pkt_cb_t cb, void *data)
 610{
 611	struct intel_pt_pkt_info pkt_info;
 612	const unsigned char *buf = decoder->buf;
 613	enum intel_pt_pkt_ctx pkt_ctx = decoder->pkt_ctx;
 614	size_t len = decoder->len;
 615	int ret;
 616
 617	pkt_info.decoder          = decoder;
 618	pkt_info.pos              = decoder->pos;
 619	pkt_info.pkt_len          = decoder->pkt_step;
 620	pkt_info.last_packet_type = decoder->last_packet_type;
 621	pkt_info.data             = data;
 622
 623	while (1) {
 624		do {
 625			pkt_info.pos += pkt_info.pkt_len;
 626			buf          += pkt_info.pkt_len;
 627			len          -= pkt_info.pkt_len;
 628
 629			if (!len)
 630				return INTEL_PT_NEED_MORE_BYTES;
 631
 632			ret = intel_pt_get_packet(buf, len, &pkt_info.packet,
 633						  &pkt_ctx);
 634			if (!ret)
 635				return INTEL_PT_NEED_MORE_BYTES;
 636			if (ret < 0)
 637				return ret;
 638
 639			pkt_info.pkt_len = ret;
 640		} while (pkt_info.packet.type == INTEL_PT_PAD);
 641
 642		ret = cb(&pkt_info);
 643		if (ret)
 644			return 0;
 645
 646		pkt_info.last_packet_type = pkt_info.packet.type;
 647	}
 648}
 649
 650struct intel_pt_calc_cyc_to_tsc_info {
 651	uint64_t        cycle_cnt;
 652	unsigned int    cbr;
 653	uint32_t        last_mtc;
 654	uint64_t        ctc_timestamp;
 655	uint64_t        ctc_delta;
 656	uint64_t        tsc_timestamp;
 657	uint64_t        timestamp;
 658	bool            have_tma;
 659	bool            fixup_last_mtc;
 660	bool            from_mtc;
 661	double          cbr_cyc_to_tsc;
 662};
 663
 664/*
 665 * MTC provides a 8-bit slice of CTC but the TMA packet only provides the lower
 666 * 16 bits of CTC. If mtc_shift > 8 then some of the MTC bits are not in the CTC
 667 * provided by the TMA packet. Fix-up the last_mtc calculated from the TMA
 668 * packet by copying the missing bits from the current MTC assuming the least
 669 * difference between the two, and that the current MTC comes after last_mtc.
 670 */
 671static void intel_pt_fixup_last_mtc(uint32_t mtc, int mtc_shift,
 672				    uint32_t *last_mtc)
 673{
 674	uint32_t first_missing_bit = 1U << (16 - mtc_shift);
 675	uint32_t mask = ~(first_missing_bit - 1);
 676
 677	*last_mtc |= mtc & mask;
 678	if (*last_mtc >= mtc) {
 679		*last_mtc -= first_missing_bit;
 680		*last_mtc &= 0xff;
 681	}
 682}
 683
 684static int intel_pt_calc_cyc_cb(struct intel_pt_pkt_info *pkt_info)
 685{
 686	struct intel_pt_decoder *decoder = pkt_info->decoder;
 687	struct intel_pt_calc_cyc_to_tsc_info *data = pkt_info->data;
 688	uint64_t timestamp;
 689	double cyc_to_tsc;
 690	unsigned int cbr;
 691	uint32_t mtc, mtc_delta, ctc, fc, ctc_rem;
 692
 693	switch (pkt_info->packet.type) {
 694	case INTEL_PT_TNT:
 695	case INTEL_PT_TIP_PGE:
 696	case INTEL_PT_TIP:
 697	case INTEL_PT_FUP:
 698	case INTEL_PT_PSB:
 699	case INTEL_PT_PIP:
 700	case INTEL_PT_MODE_EXEC:
 701	case INTEL_PT_MODE_TSX:
 702	case INTEL_PT_PSBEND:
 703	case INTEL_PT_PAD:
 704	case INTEL_PT_VMCS:
 705	case INTEL_PT_MNT:
 706	case INTEL_PT_PTWRITE:
 707	case INTEL_PT_PTWRITE_IP:
 708	case INTEL_PT_BBP:
 709	case INTEL_PT_BIP:
 710	case INTEL_PT_BEP:
 711	case INTEL_PT_BEP_IP:
 
 
 
 712		return 0;
 713
 714	case INTEL_PT_MTC:
 715		if (!data->have_tma)
 716			return 0;
 717
 718		mtc = pkt_info->packet.payload;
 719		if (decoder->mtc_shift > 8 && data->fixup_last_mtc) {
 720			data->fixup_last_mtc = false;
 721			intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
 722						&data->last_mtc);
 723		}
 724		if (mtc > data->last_mtc)
 725			mtc_delta = mtc - data->last_mtc;
 726		else
 727			mtc_delta = mtc + 256 - data->last_mtc;
 728		data->ctc_delta += mtc_delta << decoder->mtc_shift;
 729		data->last_mtc = mtc;
 730
 731		if (decoder->tsc_ctc_mult) {
 732			timestamp = data->ctc_timestamp +
 733				data->ctc_delta * decoder->tsc_ctc_mult;
 734		} else {
 735			timestamp = data->ctc_timestamp +
 736				multdiv(data->ctc_delta,
 737					decoder->tsc_ctc_ratio_n,
 738					decoder->tsc_ctc_ratio_d);
 739		}
 740
 741		if (timestamp < data->timestamp)
 742			return 1;
 743
 744		if (pkt_info->last_packet_type != INTEL_PT_CYC) {
 745			data->timestamp = timestamp;
 746			return 0;
 747		}
 748
 749		break;
 750
 751	case INTEL_PT_TSC:
 752		/*
 753		 * For now, do not support using TSC packets - refer
 754		 * intel_pt_calc_cyc_to_tsc().
 755		 */
 756		if (data->from_mtc)
 757			return 1;
 758		timestamp = pkt_info->packet.payload |
 759			    (data->timestamp & (0xffULL << 56));
 760		if (data->from_mtc && timestamp < data->timestamp &&
 761		    data->timestamp - timestamp < decoder->tsc_slip)
 762			return 1;
 763		if (timestamp < data->timestamp)
 764			timestamp += (1ULL << 56);
 765		if (pkt_info->last_packet_type != INTEL_PT_CYC) {
 766			if (data->from_mtc)
 767				return 1;
 768			data->tsc_timestamp = timestamp;
 769			data->timestamp = timestamp;
 770			return 0;
 771		}
 772		break;
 773
 774	case INTEL_PT_TMA:
 775		if (data->from_mtc)
 776			return 1;
 777
 778		if (!decoder->tsc_ctc_ratio_d)
 779			return 0;
 780
 781		ctc = pkt_info->packet.payload;
 782		fc = pkt_info->packet.count;
 783		ctc_rem = ctc & decoder->ctc_rem_mask;
 784
 785		data->last_mtc = (ctc >> decoder->mtc_shift) & 0xff;
 786
 787		data->ctc_timestamp = data->tsc_timestamp - fc;
 788		if (decoder->tsc_ctc_mult) {
 789			data->ctc_timestamp -= ctc_rem * decoder->tsc_ctc_mult;
 790		} else {
 791			data->ctc_timestamp -=
 792				multdiv(ctc_rem, decoder->tsc_ctc_ratio_n,
 793					decoder->tsc_ctc_ratio_d);
 794		}
 795
 796		data->ctc_delta = 0;
 797		data->have_tma = true;
 798		data->fixup_last_mtc = true;
 799
 800		return 0;
 801
 802	case INTEL_PT_CYC:
 803		data->cycle_cnt += pkt_info->packet.payload;
 804		return 0;
 805
 806	case INTEL_PT_CBR:
 807		cbr = pkt_info->packet.payload;
 808		if (data->cbr && data->cbr != cbr)
 809			return 1;
 810		data->cbr = cbr;
 811		data->cbr_cyc_to_tsc = decoder->max_non_turbo_ratio_fp / cbr;
 812		return 0;
 813
 814	case INTEL_PT_TIP_PGD:
 815	case INTEL_PT_TRACESTOP:
 816	case INTEL_PT_EXSTOP:
 817	case INTEL_PT_EXSTOP_IP:
 818	case INTEL_PT_MWAIT:
 819	case INTEL_PT_PWRE:
 820	case INTEL_PT_PWRX:
 821	case INTEL_PT_OVF:
 822	case INTEL_PT_BAD: /* Does not happen */
 823	default:
 824		return 1;
 825	}
 826
 827	if (!data->cbr && decoder->cbr) {
 828		data->cbr = decoder->cbr;
 829		data->cbr_cyc_to_tsc = decoder->cbr_cyc_to_tsc;
 830	}
 831
 832	if (!data->cycle_cnt)
 833		return 1;
 834
 835	cyc_to_tsc = (double)(timestamp - decoder->timestamp) / data->cycle_cnt;
 836
 837	if (data->cbr && cyc_to_tsc > data->cbr_cyc_to_tsc &&
 838	    cyc_to_tsc / data->cbr_cyc_to_tsc > 1.25) {
 839		intel_pt_log("Timestamp: calculated %g TSC ticks per cycle too big (c.f. CBR-based value %g), pos " x64_fmt "\n",
 840			     cyc_to_tsc, data->cbr_cyc_to_tsc, pkt_info->pos);
 841		return 1;
 842	}
 843
 844	decoder->calc_cyc_to_tsc = cyc_to_tsc;
 845	decoder->have_calc_cyc_to_tsc = true;
 846
 847	if (data->cbr) {
 848		intel_pt_log("Timestamp: calculated %g TSC ticks per cycle c.f. CBR-based value %g, pos " x64_fmt "\n",
 849			     cyc_to_tsc, data->cbr_cyc_to_tsc, pkt_info->pos);
 850	} else {
 851		intel_pt_log("Timestamp: calculated %g TSC ticks per cycle c.f. unknown CBR-based value, pos " x64_fmt "\n",
 852			     cyc_to_tsc, pkt_info->pos);
 853	}
 854
 855	return 1;
 856}
 857
 858static void intel_pt_calc_cyc_to_tsc(struct intel_pt_decoder *decoder,
 859				     bool from_mtc)
 860{
 861	struct intel_pt_calc_cyc_to_tsc_info data = {
 862		.cycle_cnt      = 0,
 863		.cbr            = 0,
 864		.last_mtc       = decoder->last_mtc,
 865		.ctc_timestamp  = decoder->ctc_timestamp,
 866		.ctc_delta      = decoder->ctc_delta,
 867		.tsc_timestamp  = decoder->tsc_timestamp,
 868		.timestamp      = decoder->timestamp,
 869		.have_tma       = decoder->have_tma,
 870		.fixup_last_mtc = decoder->fixup_last_mtc,
 871		.from_mtc       = from_mtc,
 872		.cbr_cyc_to_tsc = 0,
 873	};
 874
 875	/*
 876	 * For now, do not support using TSC packets for at least the reasons:
 877	 * 1) timing might have stopped
 878	 * 2) TSC packets within PSB+ can slip against CYC packets
 879	 */
 880	if (!from_mtc)
 881		return;
 882
 883	intel_pt_pkt_lookahead(decoder, intel_pt_calc_cyc_cb, &data);
 884}
 885
 886static int intel_pt_get_next_packet(struct intel_pt_decoder *decoder)
 887{
 888	int ret;
 889
 890	decoder->last_packet_type = decoder->packet.type;
 891
 892	do {
 893		decoder->pos += decoder->pkt_step;
 894		decoder->buf += decoder->pkt_step;
 895		decoder->len -= decoder->pkt_step;
 896
 897		if (!decoder->len) {
 898			ret = intel_pt_get_next_data(decoder, false);
 899			if (ret)
 900				return ret;
 901		}
 902
 903		decoder->prev_pkt_ctx = decoder->pkt_ctx;
 904		ret = intel_pt_get_packet(decoder->buf, decoder->len,
 905					  &decoder->packet, &decoder->pkt_ctx);
 906		if (ret == INTEL_PT_NEED_MORE_BYTES && BITS_PER_LONG == 32 &&
 907		    decoder->len < INTEL_PT_PKT_MAX_SZ && !decoder->next_buf) {
 908			ret = intel_pt_get_split_packet(decoder);
 909			if (ret < 0)
 910				return ret;
 911		}
 912		if (ret <= 0)
 913			return intel_pt_bad_packet(decoder);
 914
 915		decoder->pkt_len = ret;
 916		decoder->pkt_step = ret;
 917		intel_pt_decoder_log_packet(decoder);
 918	} while (decoder->packet.type == INTEL_PT_PAD);
 919
 920	return 0;
 921}
 922
 923static uint64_t intel_pt_next_period(struct intel_pt_decoder *decoder)
 924{
 925	uint64_t timestamp, masked_timestamp;
 926
 927	timestamp = decoder->timestamp + decoder->timestamp_insn_cnt;
 928	masked_timestamp = timestamp & decoder->period_mask;
 929	if (decoder->continuous_period) {
 930		if (masked_timestamp > decoder->last_masked_timestamp)
 931			return 1;
 932	} else {
 933		timestamp += 1;
 934		masked_timestamp = timestamp & decoder->period_mask;
 935		if (masked_timestamp > decoder->last_masked_timestamp) {
 936			decoder->last_masked_timestamp = masked_timestamp;
 937			decoder->continuous_period = true;
 938		}
 939	}
 940
 941	if (masked_timestamp < decoder->last_masked_timestamp)
 942		return decoder->period_ticks;
 943
 944	return decoder->period_ticks - (timestamp - masked_timestamp);
 945}
 946
 947static uint64_t intel_pt_next_sample(struct intel_pt_decoder *decoder)
 948{
 949	switch (decoder->period_type) {
 950	case INTEL_PT_PERIOD_INSTRUCTIONS:
 951		return decoder->period - decoder->period_insn_cnt;
 952	case INTEL_PT_PERIOD_TICKS:
 953		return intel_pt_next_period(decoder);
 954	case INTEL_PT_PERIOD_NONE:
 955	case INTEL_PT_PERIOD_MTC:
 956	default:
 957		return 0;
 958	}
 959}
 960
 961static void intel_pt_sample_insn(struct intel_pt_decoder *decoder)
 962{
 963	uint64_t timestamp, masked_timestamp;
 964
 965	switch (decoder->period_type) {
 966	case INTEL_PT_PERIOD_INSTRUCTIONS:
 967		decoder->period_insn_cnt = 0;
 968		break;
 969	case INTEL_PT_PERIOD_TICKS:
 970		timestamp = decoder->timestamp + decoder->timestamp_insn_cnt;
 971		masked_timestamp = timestamp & decoder->period_mask;
 972		if (masked_timestamp > decoder->last_masked_timestamp)
 973			decoder->last_masked_timestamp = masked_timestamp;
 974		else
 975			decoder->last_masked_timestamp += decoder->period_ticks;
 976		break;
 977	case INTEL_PT_PERIOD_NONE:
 978	case INTEL_PT_PERIOD_MTC:
 979	default:
 980		break;
 981	}
 982
 983	decoder->state.type |= INTEL_PT_INSTRUCTION;
 984}
 985
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 986static int intel_pt_walk_insn(struct intel_pt_decoder *decoder,
 987			      struct intel_pt_insn *intel_pt_insn, uint64_t ip)
 988{
 989	uint64_t max_insn_cnt, insn_cnt = 0;
 990	int err;
 991
 992	if (!decoder->mtc_insn)
 993		decoder->mtc_insn = true;
 994
 995	max_insn_cnt = intel_pt_next_sample(decoder);
 996
 997	err = decoder->walk_insn(intel_pt_insn, &insn_cnt, &decoder->ip, ip,
 998				 max_insn_cnt, decoder->data);
 999
1000	decoder->tot_insn_cnt += insn_cnt;
1001	decoder->timestamp_insn_cnt += insn_cnt;
1002	decoder->sample_insn_cnt += insn_cnt;
1003	decoder->period_insn_cnt += insn_cnt;
1004
1005	if (err) {
1006		decoder->no_progress = 0;
1007		decoder->pkt_state = INTEL_PT_STATE_ERR2;
1008		intel_pt_log_at("ERROR: Failed to get instruction",
1009				decoder->ip);
1010		if (err == -ENOENT)
1011			return -ENOLINK;
1012		return -EILSEQ;
1013	}
1014
1015	if (ip && decoder->ip == ip) {
1016		err = -EAGAIN;
1017		goto out;
1018	}
1019
1020	if (max_insn_cnt && insn_cnt >= max_insn_cnt)
1021		intel_pt_sample_insn(decoder);
1022
1023	if (intel_pt_insn->branch == INTEL_PT_BR_NO_BRANCH) {
1024		decoder->state.type = INTEL_PT_INSTRUCTION;
1025		decoder->state.from_ip = decoder->ip;
1026		decoder->state.to_ip = 0;
1027		decoder->ip += intel_pt_insn->length;
1028		err = INTEL_PT_RETURN;
1029		goto out;
1030	}
1031
1032	if (intel_pt_insn->op == INTEL_PT_OP_CALL) {
1033		/* Zero-length calls are excluded */
1034		if (intel_pt_insn->branch != INTEL_PT_BR_UNCONDITIONAL ||
1035		    intel_pt_insn->rel) {
1036			err = intel_pt_push(&decoder->stack, decoder->ip +
1037					    intel_pt_insn->length);
1038			if (err)
1039				goto out;
1040		}
1041	} else if (intel_pt_insn->op == INTEL_PT_OP_RET) {
1042		decoder->ret_addr = intel_pt_pop(&decoder->stack);
1043	}
1044
1045	if (intel_pt_insn->branch == INTEL_PT_BR_UNCONDITIONAL) {
1046		int cnt = decoder->no_progress++;
1047
1048		decoder->state.from_ip = decoder->ip;
1049		decoder->ip += intel_pt_insn->length +
1050				intel_pt_insn->rel;
1051		decoder->state.to_ip = decoder->ip;
1052		err = INTEL_PT_RETURN;
1053
1054		/*
1055		 * Check for being stuck in a loop.  This can happen if a
1056		 * decoder error results in the decoder erroneously setting the
1057		 * ip to an address that is itself in an infinite loop that
1058		 * consumes no packets.  When that happens, there must be an
1059		 * unconditional branch.
1060		 */
1061		if (cnt) {
1062			if (cnt == 1) {
1063				decoder->stuck_ip = decoder->state.to_ip;
1064				decoder->stuck_ip_prd = 1;
1065				decoder->stuck_ip_cnt = 1;
1066			} else if (cnt > INTEL_PT_MAX_LOOPS ||
1067				   decoder->state.to_ip == decoder->stuck_ip) {
1068				intel_pt_log_at("ERROR: Never-ending loop",
1069						decoder->state.to_ip);
1070				decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1071				err = -ELOOP;
1072				goto out;
1073			} else if (!--decoder->stuck_ip_cnt) {
1074				decoder->stuck_ip_prd += 1;
1075				decoder->stuck_ip_cnt = decoder->stuck_ip_prd;
1076				decoder->stuck_ip = decoder->state.to_ip;
1077			}
1078		}
1079		goto out_no_progress;
1080	}
1081out:
1082	decoder->no_progress = 0;
1083out_no_progress:
1084	decoder->state.insn_op = intel_pt_insn->op;
1085	decoder->state.insn_len = intel_pt_insn->length;
1086	memcpy(decoder->state.insn, intel_pt_insn->buf,
1087	       INTEL_PT_INSN_BUF_SZ);
1088
1089	if (decoder->tx_flags & INTEL_PT_IN_TX)
1090		decoder->state.flags |= INTEL_PT_IN_TX;
1091
1092	return err;
1093}
1094
1095static bool intel_pt_fup_event(struct intel_pt_decoder *decoder)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1096{
 
 
1097	bool ret = false;
1098
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1099	if (decoder->set_fup_tx_flags) {
1100		decoder->set_fup_tx_flags = false;
1101		decoder->tx_flags = decoder->fup_tx_flags;
1102		decoder->state.type = INTEL_PT_TRANSACTION;
1103		decoder->state.from_ip = decoder->ip;
1104		decoder->state.to_ip = 0;
1105		decoder->state.flags = decoder->fup_tx_flags;
1106		return true;
1107	}
1108	if (decoder->set_fup_ptw) {
1109		decoder->set_fup_ptw = false;
1110		decoder->state.type = INTEL_PT_PTW;
1111		decoder->state.flags |= INTEL_PT_FUP_IP;
1112		decoder->state.from_ip = decoder->ip;
1113		decoder->state.to_ip = 0;
1114		decoder->state.ptw_payload = decoder->fup_ptw_payload;
1115		return true;
1116	}
1117	if (decoder->set_fup_mwait) {
1118		decoder->set_fup_mwait = false;
1119		decoder->state.type = INTEL_PT_MWAIT_OP;
1120		decoder->state.from_ip = decoder->ip;
1121		decoder->state.to_ip = 0;
1122		decoder->state.mwait_payload = decoder->fup_mwait_payload;
1123		ret = true;
1124	}
1125	if (decoder->set_fup_pwre) {
1126		decoder->set_fup_pwre = false;
1127		decoder->state.type |= INTEL_PT_PWR_ENTRY;
1128		decoder->state.type &= ~INTEL_PT_BRANCH;
1129		decoder->state.from_ip = decoder->ip;
1130		decoder->state.to_ip = 0;
1131		decoder->state.pwre_payload = decoder->fup_pwre_payload;
1132		ret = true;
1133	}
1134	if (decoder->set_fup_exstop) {
1135		decoder->set_fup_exstop = false;
1136		decoder->state.type |= INTEL_PT_EX_STOP;
1137		decoder->state.type &= ~INTEL_PT_BRANCH;
1138		decoder->state.flags |= INTEL_PT_FUP_IP;
1139		decoder->state.from_ip = decoder->ip;
1140		decoder->state.to_ip = 0;
1141		ret = true;
1142	}
1143	if (decoder->set_fup_bep) {
1144		decoder->set_fup_bep = false;
1145		decoder->state.type |= INTEL_PT_BLK_ITEMS;
1146		decoder->state.type &= ~INTEL_PT_BRANCH;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1147		decoder->state.from_ip = decoder->ip;
1148		decoder->state.to_ip = 0;
1149		ret = true;
 
 
 
1150	}
1151	return ret;
1152}
1153
1154static inline bool intel_pt_fup_with_nlip(struct intel_pt_decoder *decoder,
1155					  struct intel_pt_insn *intel_pt_insn,
1156					  uint64_t ip, int err)
1157{
1158	return decoder->flags & INTEL_PT_FUP_WITH_NLIP && !err &&
1159	       intel_pt_insn->branch == INTEL_PT_BR_INDIRECT &&
1160	       ip == decoder->ip + intel_pt_insn->length;
1161}
1162
1163static int intel_pt_walk_fup(struct intel_pt_decoder *decoder)
1164{
1165	struct intel_pt_insn intel_pt_insn;
1166	uint64_t ip;
1167	int err;
1168
1169	ip = decoder->last_ip;
1170
1171	while (1) {
1172		err = intel_pt_walk_insn(decoder, &intel_pt_insn, ip);
1173		if (err == INTEL_PT_RETURN)
1174			return 0;
1175		if (err == -EAGAIN ||
1176		    intel_pt_fup_with_nlip(decoder, &intel_pt_insn, ip, err)) {
 
 
1177			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1178			if (intel_pt_fup_event(decoder))
1179				return 0;
1180			return -EAGAIN;
1181		}
1182		decoder->set_fup_tx_flags = false;
1183		if (err)
1184			return err;
1185
1186		if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1187			intel_pt_log_at("ERROR: Unexpected indirect branch",
1188					decoder->ip);
1189			decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1190			return -ENOENT;
1191		}
1192
1193		if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1194			intel_pt_log_at("ERROR: Unexpected conditional branch",
1195					decoder->ip);
1196			decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1197			return -ENOENT;
1198		}
1199
1200		intel_pt_bug(decoder);
1201	}
1202}
1203
1204static int intel_pt_walk_tip(struct intel_pt_decoder *decoder)
1205{
1206	struct intel_pt_insn intel_pt_insn;
1207	int err;
1208
1209	err = intel_pt_walk_insn(decoder, &intel_pt_insn, 0);
1210	if (err == INTEL_PT_RETURN &&
1211	    decoder->pgd_ip &&
1212	    decoder->pkt_state == INTEL_PT_STATE_TIP_PGD &&
1213	    (decoder->state.type & INTEL_PT_BRANCH) &&
1214	    decoder->pgd_ip(decoder->state.to_ip, decoder->data)) {
1215		/* Unconditional branch leaving filter region */
1216		decoder->no_progress = 0;
1217		decoder->pge = false;
1218		decoder->continuous_period = false;
1219		decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1220		decoder->state.type |= INTEL_PT_TRACE_END;
 
1221		return 0;
1222	}
1223	if (err == INTEL_PT_RETURN)
1224		return 0;
1225	if (err)
1226		return err;
1227
 
 
 
1228	if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1229		if (decoder->pkt_state == INTEL_PT_STATE_TIP_PGD) {
1230			decoder->pge = false;
1231			decoder->continuous_period = false;
1232			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1233			decoder->state.from_ip = decoder->ip;
1234			if (decoder->packet.count == 0) {
1235				decoder->state.to_ip = 0;
1236			} else {
1237				decoder->state.to_ip = decoder->last_ip;
1238				decoder->ip = decoder->last_ip;
1239			}
1240			decoder->state.type |= INTEL_PT_TRACE_END;
1241		} else {
1242			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1243			decoder->state.from_ip = decoder->ip;
1244			if (decoder->packet.count == 0) {
1245				decoder->state.to_ip = 0;
1246			} else {
1247				decoder->state.to_ip = decoder->last_ip;
1248				decoder->ip = decoder->last_ip;
1249			}
1250		}
1251		return 0;
1252	}
1253
1254	if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1255		uint64_t to_ip = decoder->ip + intel_pt_insn.length +
1256				 intel_pt_insn.rel;
1257
1258		if (decoder->pgd_ip &&
1259		    decoder->pkt_state == INTEL_PT_STATE_TIP_PGD &&
1260		    decoder->pgd_ip(to_ip, decoder->data)) {
1261			/* Conditional branch leaving filter region */
1262			decoder->pge = false;
1263			decoder->continuous_period = false;
1264			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1265			decoder->ip = to_ip;
1266			decoder->state.from_ip = decoder->ip;
1267			decoder->state.to_ip = to_ip;
1268			decoder->state.type |= INTEL_PT_TRACE_END;
1269			return 0;
1270		}
1271		intel_pt_log_at("ERROR: Conditional branch when expecting indirect branch",
1272				decoder->ip);
1273		decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1274		return -ENOENT;
1275	}
1276
1277	return intel_pt_bug(decoder);
1278}
1279
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1280static int intel_pt_walk_tnt(struct intel_pt_decoder *decoder)
1281{
1282	struct intel_pt_insn intel_pt_insn;
1283	int err;
1284
1285	while (1) {
 
 
1286		err = intel_pt_walk_insn(decoder, &intel_pt_insn, 0);
1287		if (err == INTEL_PT_RETURN)
 
1288			return 0;
1289		if (err)
 
 
1290			return err;
 
1291
1292		if (intel_pt_insn.op == INTEL_PT_OP_RET) {
1293			if (!decoder->return_compression) {
1294				intel_pt_log_at("ERROR: RET when expecting conditional branch",
1295						decoder->ip);
1296				decoder->pkt_state = INTEL_PT_STATE_ERR3;
1297				return -ENOENT;
1298			}
1299			if (!decoder->ret_addr) {
1300				intel_pt_log_at("ERROR: Bad RET compression (stack empty)",
1301						decoder->ip);
1302				decoder->pkt_state = INTEL_PT_STATE_ERR3;
1303				return -ENOENT;
1304			}
1305			if (!(decoder->tnt.payload & BIT63)) {
1306				intel_pt_log_at("ERROR: Bad RET compression (TNT=N)",
1307						decoder->ip);
1308				decoder->pkt_state = INTEL_PT_STATE_ERR3;
1309				return -ENOENT;
1310			}
1311			decoder->tnt.count -= 1;
1312			if (decoder->tnt.count)
1313				decoder->pkt_state = INTEL_PT_STATE_TNT_CONT;
1314			else
1315				decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1316			decoder->tnt.payload <<= 1;
1317			decoder->state.from_ip = decoder->ip;
1318			decoder->ip = decoder->ret_addr;
1319			decoder->state.to_ip = decoder->ip;
1320			return 0;
1321		}
1322
1323		if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1324			/* Handle deferred TIPs */
1325			err = intel_pt_get_next_packet(decoder);
1326			if (err)
1327				return err;
1328			if (decoder->packet.type != INTEL_PT_TIP ||
1329			    decoder->packet.count == 0) {
1330				intel_pt_log_at("ERROR: Missing deferred TIP for indirect branch",
1331						decoder->ip);
1332				decoder->pkt_state = INTEL_PT_STATE_ERR3;
1333				decoder->pkt_step = 0;
1334				return -ENOENT;
1335			}
1336			intel_pt_set_last_ip(decoder);
1337			decoder->state.from_ip = decoder->ip;
1338			decoder->state.to_ip = decoder->last_ip;
1339			decoder->ip = decoder->last_ip;
 
 
1340			return 0;
1341		}
1342
1343		if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1344			decoder->tnt.count -= 1;
1345			if (decoder->tnt.count)
1346				decoder->pkt_state = INTEL_PT_STATE_TNT_CONT;
1347			else
1348				decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1349			if (decoder->tnt.payload & BIT63) {
1350				decoder->tnt.payload <<= 1;
1351				decoder->state.from_ip = decoder->ip;
1352				decoder->ip += intel_pt_insn.length +
1353					       intel_pt_insn.rel;
1354				decoder->state.to_ip = decoder->ip;
1355				return 0;
1356			}
1357			/* Instruction sample for a non-taken branch */
1358			if (decoder->state.type & INTEL_PT_INSTRUCTION) {
1359				decoder->tnt.payload <<= 1;
1360				decoder->state.type = INTEL_PT_INSTRUCTION;
1361				decoder->state.from_ip = decoder->ip;
1362				decoder->state.to_ip = 0;
1363				decoder->ip += intel_pt_insn.length;
1364				return 0;
1365			}
1366			decoder->sample_cyc = false;
1367			decoder->ip += intel_pt_insn.length;
1368			if (!decoder->tnt.count) {
1369				intel_pt_update_sample_time(decoder);
1370				return -EAGAIN;
1371			}
1372			decoder->tnt.payload <<= 1;
1373			continue;
1374		}
1375
1376		return intel_pt_bug(decoder);
1377	}
1378}
1379
1380static int intel_pt_mode_tsx(struct intel_pt_decoder *decoder, bool *no_tip)
1381{
1382	unsigned int fup_tx_flags;
1383	int err;
1384
1385	fup_tx_flags = decoder->packet.payload &
1386		       (INTEL_PT_IN_TX | INTEL_PT_ABORT_TX);
1387	err = intel_pt_get_next_packet(decoder);
1388	if (err)
1389		return err;
1390	if (decoder->packet.type == INTEL_PT_FUP) {
1391		decoder->fup_tx_flags = fup_tx_flags;
1392		decoder->set_fup_tx_flags = true;
1393		if (!(decoder->fup_tx_flags & INTEL_PT_ABORT_TX))
1394			*no_tip = true;
1395	} else {
1396		intel_pt_log_at("ERROR: Missing FUP after MODE.TSX",
1397				decoder->pos);
1398		intel_pt_update_in_tx(decoder);
1399	}
1400	return 0;
1401}
1402
 
 
 
 
 
 
 
 
 
 
 
 
 
1403static uint64_t intel_pt_8b_tsc(uint64_t timestamp, uint64_t ref_timestamp)
1404{
1405	timestamp |= (ref_timestamp & (0xffULL << 56));
1406
1407	if (timestamp < ref_timestamp) {
1408		if (ref_timestamp - timestamp > (1ULL << 55))
1409			timestamp += (1ULL << 56);
1410	} else {
1411		if (timestamp - ref_timestamp > (1ULL << 55))
1412			timestamp -= (1ULL << 56);
1413	}
1414
1415	return timestamp;
1416}
1417
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1418static void intel_pt_calc_tsc_timestamp(struct intel_pt_decoder *decoder)
1419{
1420	uint64_t timestamp;
 
1421
1422	decoder->have_tma = false;
1423
1424	if (decoder->ref_timestamp) {
1425		timestamp = intel_pt_8b_tsc(decoder->packet.payload,
1426					    decoder->ref_timestamp);
1427		decoder->tsc_timestamp = timestamp;
1428		decoder->timestamp = timestamp;
1429		decoder->ref_timestamp = 0;
1430		decoder->timestamp_insn_cnt = 0;
1431	} else if (decoder->timestamp) {
1432		timestamp = decoder->packet.payload |
1433			    (decoder->timestamp & (0xffULL << 56));
1434		decoder->tsc_timestamp = timestamp;
1435		if (timestamp < decoder->timestamp &&
1436		    decoder->timestamp - timestamp < decoder->tsc_slip) {
1437			intel_pt_log_to("Suppressing backwards timestamp",
1438					timestamp);
1439			timestamp = decoder->timestamp;
1440		}
1441		if (timestamp < decoder->timestamp) {
1442			intel_pt_log_to("Wraparound timestamp", timestamp);
1443			timestamp += (1ULL << 56);
1444			decoder->tsc_timestamp = timestamp;
 
 
 
 
 
 
 
1445		}
 
 
 
 
1446		decoder->timestamp = timestamp;
1447		decoder->timestamp_insn_cnt = 0;
1448	}
1449
1450	if (decoder->last_packet_type == INTEL_PT_CYC) {
1451		decoder->cyc_ref_timestamp = decoder->timestamp;
1452		decoder->cycle_cnt = 0;
1453		decoder->have_calc_cyc_to_tsc = false;
1454		intel_pt_calc_cyc_to_tsc(decoder, false);
1455	}
1456
1457	intel_pt_log_to("Setting timestamp", decoder->timestamp);
1458}
1459
1460static int intel_pt_overflow(struct intel_pt_decoder *decoder)
1461{
1462	intel_pt_log("ERROR: Buffer overflow\n");
1463	intel_pt_clear_tx_flags(decoder);
 
1464	decoder->timestamp_insn_cnt = 0;
1465	decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
 
 
 
 
1466	decoder->overflow = true;
1467	return -EOVERFLOW;
1468}
1469
1470static inline void intel_pt_mtc_cyc_cnt_pge(struct intel_pt_decoder *decoder)
1471{
1472	if (decoder->have_cyc)
1473		return;
1474
1475	decoder->cyc_cnt_timestamp = decoder->timestamp;
1476	decoder->base_cyc_cnt = decoder->tot_cyc_cnt;
1477}
1478
1479static inline void intel_pt_mtc_cyc_cnt_cbr(struct intel_pt_decoder *decoder)
1480{
1481	decoder->tsc_to_cyc = decoder->cbr / decoder->max_non_turbo_ratio_fp;
1482
1483	if (decoder->pge)
1484		intel_pt_mtc_cyc_cnt_pge(decoder);
1485}
1486
1487static inline void intel_pt_mtc_cyc_cnt_upd(struct intel_pt_decoder *decoder)
1488{
1489	uint64_t tot_cyc_cnt, tsc_delta;
1490
1491	if (decoder->have_cyc)
1492		return;
1493
1494	decoder->sample_cyc = true;
1495
1496	if (!decoder->pge || decoder->timestamp <= decoder->cyc_cnt_timestamp)
1497		return;
1498
1499	tsc_delta = decoder->timestamp - decoder->cyc_cnt_timestamp;
1500	tot_cyc_cnt = tsc_delta * decoder->tsc_to_cyc + decoder->base_cyc_cnt;
1501
1502	if (tot_cyc_cnt > decoder->tot_cyc_cnt)
1503		decoder->tot_cyc_cnt = tot_cyc_cnt;
1504}
1505
1506static void intel_pt_calc_tma(struct intel_pt_decoder *decoder)
1507{
1508	uint32_t ctc = decoder->packet.payload;
1509	uint32_t fc = decoder->packet.count;
1510	uint32_t ctc_rem = ctc & decoder->ctc_rem_mask;
1511
1512	if (!decoder->tsc_ctc_ratio_d)
1513		return;
1514
1515	if (decoder->pge && !decoder->in_psb)
1516		intel_pt_mtc_cyc_cnt_pge(decoder);
1517	else
1518		intel_pt_mtc_cyc_cnt_upd(decoder);
1519
1520	decoder->last_mtc = (ctc >> decoder->mtc_shift) & 0xff;
 
1521	decoder->ctc_timestamp = decoder->tsc_timestamp - fc;
1522	if (decoder->tsc_ctc_mult) {
1523		decoder->ctc_timestamp -= ctc_rem * decoder->tsc_ctc_mult;
1524	} else {
1525		decoder->ctc_timestamp -= multdiv(ctc_rem,
1526						  decoder->tsc_ctc_ratio_n,
1527						  decoder->tsc_ctc_ratio_d);
1528	}
1529	decoder->ctc_delta = 0;
1530	decoder->have_tma = true;
1531	decoder->fixup_last_mtc = true;
1532	intel_pt_log("CTC timestamp " x64_fmt " last MTC %#x  CTC rem %#x\n",
1533		     decoder->ctc_timestamp, decoder->last_mtc, ctc_rem);
1534}
1535
1536static void intel_pt_calc_mtc_timestamp(struct intel_pt_decoder *decoder)
1537{
1538	uint64_t timestamp;
1539	uint32_t mtc, mtc_delta;
1540
1541	if (!decoder->have_tma)
1542		return;
1543
1544	mtc = decoder->packet.payload;
1545
1546	if (decoder->mtc_shift > 8 && decoder->fixup_last_mtc) {
1547		decoder->fixup_last_mtc = false;
1548		intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
1549					&decoder->last_mtc);
1550	}
1551
1552	if (mtc > decoder->last_mtc)
1553		mtc_delta = mtc - decoder->last_mtc;
1554	else
1555		mtc_delta = mtc + 256 - decoder->last_mtc;
1556
1557	decoder->ctc_delta += mtc_delta << decoder->mtc_shift;
1558
1559	if (decoder->tsc_ctc_mult) {
1560		timestamp = decoder->ctc_timestamp +
1561			    decoder->ctc_delta * decoder->tsc_ctc_mult;
1562	} else {
1563		timestamp = decoder->ctc_timestamp +
1564			    multdiv(decoder->ctc_delta,
1565				    decoder->tsc_ctc_ratio_n,
1566				    decoder->tsc_ctc_ratio_d);
1567	}
1568
1569	if (timestamp < decoder->timestamp)
1570		intel_pt_log("Suppressing MTC timestamp " x64_fmt " less than current timestamp " x64_fmt "\n",
1571			     timestamp, decoder->timestamp);
1572	else
1573		decoder->timestamp = timestamp;
1574
1575	intel_pt_mtc_cyc_cnt_upd(decoder);
1576
1577	decoder->timestamp_insn_cnt = 0;
1578	decoder->last_mtc = mtc;
1579
1580	if (decoder->last_packet_type == INTEL_PT_CYC) {
1581		decoder->cyc_ref_timestamp = decoder->timestamp;
1582		decoder->cycle_cnt = 0;
1583		decoder->have_calc_cyc_to_tsc = false;
1584		intel_pt_calc_cyc_to_tsc(decoder, true);
1585	}
1586
1587	intel_pt_log_to("Setting timestamp", decoder->timestamp);
1588}
1589
1590static void intel_pt_calc_cbr(struct intel_pt_decoder *decoder)
1591{
1592	unsigned int cbr = decoder->packet.payload & 0xff;
1593
1594	decoder->cbr_payload = decoder->packet.payload;
1595
1596	if (decoder->cbr == cbr)
1597		return;
1598
1599	decoder->cbr = cbr;
1600	decoder->cbr_cyc_to_tsc = decoder->max_non_turbo_ratio_fp / cbr;
 
 
1601
1602	intel_pt_mtc_cyc_cnt_cbr(decoder);
1603}
1604
1605static void intel_pt_calc_cyc_timestamp(struct intel_pt_decoder *decoder)
1606{
1607	uint64_t timestamp = decoder->cyc_ref_timestamp;
1608
1609	decoder->have_cyc = true;
1610
1611	decoder->cycle_cnt += decoder->packet.payload;
1612	if (decoder->pge)
1613		decoder->tot_cyc_cnt += decoder->packet.payload;
1614	decoder->sample_cyc = true;
1615
1616	if (!decoder->cyc_ref_timestamp)
1617		return;
1618
1619	if (decoder->have_calc_cyc_to_tsc)
1620		timestamp += decoder->cycle_cnt * decoder->calc_cyc_to_tsc;
1621	else if (decoder->cbr)
1622		timestamp += decoder->cycle_cnt * decoder->cbr_cyc_to_tsc;
1623	else
1624		return;
1625
1626	if (timestamp < decoder->timestamp)
1627		intel_pt_log("Suppressing CYC timestamp " x64_fmt " less than current timestamp " x64_fmt "\n",
1628			     timestamp, decoder->timestamp);
1629	else
1630		decoder->timestamp = timestamp;
1631
1632	decoder->timestamp_insn_cnt = 0;
1633
1634	intel_pt_log_to("Setting timestamp", decoder->timestamp);
1635}
1636
1637static void intel_pt_bbp(struct intel_pt_decoder *decoder)
1638{
1639	if (decoder->prev_pkt_ctx == INTEL_PT_NO_CTX) {
1640		memset(decoder->state.items.mask, 0, sizeof(decoder->state.items.mask));
1641		decoder->state.items.is_32_bit = false;
1642	}
1643	decoder->blk_type = decoder->packet.payload;
1644	decoder->blk_type_pos = intel_pt_blk_type_pos(decoder->blk_type);
1645	if (decoder->blk_type == INTEL_PT_GP_REGS)
1646		decoder->state.items.is_32_bit = decoder->packet.count;
1647	if (decoder->blk_type_pos < 0) {
1648		intel_pt_log("WARNING: Unknown block type %u\n",
1649			     decoder->blk_type);
1650	} else if (decoder->state.items.mask[decoder->blk_type_pos]) {
1651		intel_pt_log("WARNING: Duplicate block type %u\n",
1652			     decoder->blk_type);
1653	}
1654}
1655
1656static void intel_pt_bip(struct intel_pt_decoder *decoder)
1657{
1658	uint32_t id = decoder->packet.count;
1659	uint32_t bit = 1 << id;
1660	int pos = decoder->blk_type_pos;
1661
1662	if (pos < 0 || id >= INTEL_PT_BLK_ITEM_ID_CNT) {
1663		intel_pt_log("WARNING: Unknown block item %u type %d\n",
1664			     id, decoder->blk_type);
1665		return;
1666	}
1667
1668	if (decoder->state.items.mask[pos] & bit) {
1669		intel_pt_log("WARNING: Duplicate block item %u type %d\n",
1670			     id, decoder->blk_type);
1671	}
1672
1673	decoder->state.items.mask[pos] |= bit;
1674	decoder->state.items.val[pos][id] = decoder->packet.payload;
1675}
1676
1677/* Walk PSB+ packets when already in sync. */
1678static int intel_pt_walk_psbend(struct intel_pt_decoder *decoder)
1679{
1680	int err;
1681
1682	decoder->in_psb = true;
1683
1684	while (1) {
1685		err = intel_pt_get_next_packet(decoder);
1686		if (err)
1687			goto out;
1688
1689		switch (decoder->packet.type) {
1690		case INTEL_PT_PSBEND:
1691			err = 0;
1692			goto out;
1693
1694		case INTEL_PT_TIP_PGD:
1695		case INTEL_PT_TIP_PGE:
1696		case INTEL_PT_TIP:
1697		case INTEL_PT_TNT:
1698		case INTEL_PT_TRACESTOP:
1699		case INTEL_PT_BAD:
1700		case INTEL_PT_PSB:
1701		case INTEL_PT_PTWRITE:
1702		case INTEL_PT_PTWRITE_IP:
1703		case INTEL_PT_EXSTOP:
1704		case INTEL_PT_EXSTOP_IP:
1705		case INTEL_PT_MWAIT:
1706		case INTEL_PT_PWRE:
1707		case INTEL_PT_PWRX:
1708		case INTEL_PT_BBP:
1709		case INTEL_PT_BIP:
1710		case INTEL_PT_BEP:
1711		case INTEL_PT_BEP_IP:
 
 
 
1712			decoder->have_tma = false;
1713			intel_pt_log("ERROR: Unexpected packet\n");
1714			err = -EAGAIN;
1715			goto out;
1716
1717		case INTEL_PT_OVF:
1718			err = intel_pt_overflow(decoder);
1719			goto out;
1720
1721		case INTEL_PT_TSC:
1722			intel_pt_calc_tsc_timestamp(decoder);
1723			break;
1724
1725		case INTEL_PT_TMA:
1726			intel_pt_calc_tma(decoder);
1727			break;
1728
1729		case INTEL_PT_CBR:
1730			intel_pt_calc_cbr(decoder);
1731			break;
1732
1733		case INTEL_PT_MODE_EXEC:
1734			decoder->exec_mode = decoder->packet.payload;
1735			break;
1736
1737		case INTEL_PT_PIP:
1738			decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
1739			break;
1740
1741		case INTEL_PT_FUP:
1742			decoder->pge = true;
1743			if (decoder->packet.count) {
1744				intel_pt_set_last_ip(decoder);
1745				if (decoder->hop) {
1746					/* Act on FUP at PSBEND */
1747					decoder->ip = decoder->last_ip;
1748					decoder->hop_psb_fup = true;
1749				}
1750			}
1751			break;
1752
1753		case INTEL_PT_MODE_TSX:
1754			intel_pt_update_in_tx(decoder);
1755			break;
1756
1757		case INTEL_PT_MTC:
1758			intel_pt_calc_mtc_timestamp(decoder);
1759			if (decoder->period_type == INTEL_PT_PERIOD_MTC)
1760				decoder->state.type |= INTEL_PT_INSTRUCTION;
1761			break;
1762
1763		case INTEL_PT_CYC:
 
 
 
1764		case INTEL_PT_VMCS:
1765		case INTEL_PT_MNT:
1766		case INTEL_PT_PAD:
1767		default:
1768			break;
1769		}
1770	}
1771out:
1772	decoder->in_psb = false;
1773
1774	return err;
1775}
1776
1777static int intel_pt_walk_fup_tip(struct intel_pt_decoder *decoder)
1778{
1779	int err;
1780
1781	if (decoder->tx_flags & INTEL_PT_ABORT_TX) {
1782		decoder->tx_flags = 0;
1783		decoder->state.flags &= ~INTEL_PT_IN_TX;
1784		decoder->state.flags |= INTEL_PT_ABORT_TX;
1785	} else {
1786		decoder->state.flags |= INTEL_PT_ASYNC;
1787	}
1788
1789	while (1) {
1790		err = intel_pt_get_next_packet(decoder);
1791		if (err)
1792			return err;
1793
1794		switch (decoder->packet.type) {
1795		case INTEL_PT_TNT:
1796		case INTEL_PT_FUP:
1797		case INTEL_PT_TRACESTOP:
1798		case INTEL_PT_PSB:
1799		case INTEL_PT_TSC:
1800		case INTEL_PT_TMA:
1801		case INTEL_PT_MODE_TSX:
1802		case INTEL_PT_BAD:
1803		case INTEL_PT_PSBEND:
1804		case INTEL_PT_PTWRITE:
1805		case INTEL_PT_PTWRITE_IP:
1806		case INTEL_PT_EXSTOP:
1807		case INTEL_PT_EXSTOP_IP:
1808		case INTEL_PT_MWAIT:
1809		case INTEL_PT_PWRE:
1810		case INTEL_PT_PWRX:
1811		case INTEL_PT_BBP:
1812		case INTEL_PT_BIP:
1813		case INTEL_PT_BEP:
1814		case INTEL_PT_BEP_IP:
 
 
 
1815			intel_pt_log("ERROR: Missing TIP after FUP\n");
1816			decoder->pkt_state = INTEL_PT_STATE_ERR3;
1817			decoder->pkt_step = 0;
1818			return -ENOENT;
1819
1820		case INTEL_PT_CBR:
1821			intel_pt_calc_cbr(decoder);
1822			break;
1823
1824		case INTEL_PT_OVF:
1825			return intel_pt_overflow(decoder);
1826
1827		case INTEL_PT_TIP_PGD:
1828			decoder->state.from_ip = decoder->ip;
1829			if (decoder->packet.count == 0) {
1830				decoder->state.to_ip = 0;
1831			} else {
1832				intel_pt_set_ip(decoder);
1833				decoder->state.to_ip = decoder->ip;
1834			}
1835			decoder->pge = false;
1836			decoder->continuous_period = false;
1837			decoder->state.type |= INTEL_PT_TRACE_END;
 
1838			return 0;
1839
1840		case INTEL_PT_TIP_PGE:
1841			decoder->pge = true;
1842			intel_pt_log("Omitting PGE ip " x64_fmt "\n",
1843				     decoder->ip);
1844			decoder->state.from_ip = 0;
1845			if (decoder->packet.count == 0) {
1846				decoder->state.to_ip = 0;
1847			} else {
1848				intel_pt_set_ip(decoder);
1849				decoder->state.to_ip = decoder->ip;
1850			}
1851			decoder->state.type |= INTEL_PT_TRACE_BEGIN;
1852			intel_pt_mtc_cyc_cnt_pge(decoder);
 
1853			return 0;
1854
1855		case INTEL_PT_TIP:
1856			decoder->state.from_ip = decoder->ip;
1857			if (decoder->packet.count == 0) {
1858				decoder->state.to_ip = 0;
1859			} else {
1860				intel_pt_set_ip(decoder);
1861				decoder->state.to_ip = decoder->ip;
1862			}
 
 
1863			return 0;
1864
1865		case INTEL_PT_PIP:
1866			decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
1867			break;
1868
1869		case INTEL_PT_MTC:
1870			intel_pt_calc_mtc_timestamp(decoder);
1871			if (decoder->period_type == INTEL_PT_PERIOD_MTC)
1872				decoder->state.type |= INTEL_PT_INSTRUCTION;
1873			break;
1874
1875		case INTEL_PT_CYC:
1876			intel_pt_calc_cyc_timestamp(decoder);
1877			break;
1878
1879		case INTEL_PT_MODE_EXEC:
1880			decoder->exec_mode = decoder->packet.payload;
1881			break;
1882
1883		case INTEL_PT_VMCS:
1884		case INTEL_PT_MNT:
1885		case INTEL_PT_PAD:
1886			break;
1887
1888		default:
1889			return intel_pt_bug(decoder);
1890		}
1891	}
1892}
1893
1894static int intel_pt_resample(struct intel_pt_decoder *decoder)
1895{
1896	decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1897	decoder->state.type = INTEL_PT_INSTRUCTION;
1898	decoder->state.from_ip = decoder->ip;
1899	decoder->state.to_ip = 0;
1900	return 0;
1901}
1902
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1903#define HOP_PROCESS	0
1904#define HOP_IGNORE	1
1905#define HOP_RETURN	2
1906#define HOP_AGAIN	3
1907
1908static int intel_pt_scan_for_psb(struct intel_pt_decoder *decoder);
1909
1910/* Hop mode: Ignore TNT, do not walk code, but get ip from FUPs and TIPs */
1911static int intel_pt_hop_trace(struct intel_pt_decoder *decoder, bool *no_tip, int *err)
1912{
 
 
1913	/* Leap from PSB to PSB, getting ip from FUP within PSB+ */
1914	if (decoder->leap && !decoder->in_psb && decoder->packet.type != INTEL_PT_PSB) {
1915		*err = intel_pt_scan_for_psb(decoder);
1916		if (*err)
1917			return HOP_RETURN;
1918	}
1919
1920	switch (decoder->packet.type) {
1921	case INTEL_PT_TNT:
1922		return HOP_IGNORE;
1923
1924	case INTEL_PT_TIP_PGD:
1925		if (!decoder->packet.count)
 
 
1926			return HOP_IGNORE;
 
1927		intel_pt_set_ip(decoder);
1928		decoder->state.type |= INTEL_PT_TRACE_END;
1929		decoder->state.from_ip = 0;
1930		decoder->state.to_ip = decoder->ip;
 
1931		return HOP_RETURN;
1932
1933	case INTEL_PT_TIP:
1934		if (!decoder->packet.count)
 
1935			return HOP_IGNORE;
 
1936		intel_pt_set_ip(decoder);
1937		decoder->state.type = INTEL_PT_INSTRUCTION;
1938		decoder->state.from_ip = decoder->ip;
1939		decoder->state.to_ip = 0;
 
 
1940		return HOP_RETURN;
1941
1942	case INTEL_PT_FUP:
1943		if (!decoder->packet.count)
1944			return HOP_IGNORE;
1945		intel_pt_set_ip(decoder);
1946		if (intel_pt_fup_event(decoder))
1947			return HOP_RETURN;
1948		if (!decoder->branch_enable)
1949			*no_tip = true;
1950		if (*no_tip) {
1951			decoder->state.type = INTEL_PT_INSTRUCTION;
1952			decoder->state.from_ip = decoder->ip;
1953			decoder->state.to_ip = 0;
 
1954			return HOP_RETURN;
1955		}
 
 
1956		*err = intel_pt_walk_fup_tip(decoder);
1957		if (!*err)
1958			decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
1959		return HOP_RETURN;
1960
1961	case INTEL_PT_PSB:
 
 
1962		decoder->last_ip = 0;
1963		decoder->have_last_ip = true;
1964		decoder->hop_psb_fup = false;
1965		*err = intel_pt_walk_psbend(decoder);
1966		if (*err == -EAGAIN)
1967			return HOP_AGAIN;
1968		if (*err)
1969			return HOP_RETURN;
1970		if (decoder->hop_psb_fup) {
1971			decoder->hop_psb_fup = false;
1972			decoder->state.type = INTEL_PT_INSTRUCTION;
1973			decoder->state.from_ip = decoder->ip;
1974			decoder->state.to_ip = 0;
1975			return HOP_RETURN;
1976		}
1977		if (decoder->cbr != decoder->cbr_seen) {
1978			decoder->state.type = 0;
1979			return HOP_RETURN;
1980		}
1981		return HOP_IGNORE;
1982
1983	case INTEL_PT_BAD:
1984	case INTEL_PT_PAD:
1985	case INTEL_PT_TIP_PGE:
1986	case INTEL_PT_TSC:
1987	case INTEL_PT_TMA:
1988	case INTEL_PT_MODE_EXEC:
1989	case INTEL_PT_MODE_TSX:
1990	case INTEL_PT_MTC:
1991	case INTEL_PT_CYC:
1992	case INTEL_PT_VMCS:
1993	case INTEL_PT_PSBEND:
1994	case INTEL_PT_CBR:
1995	case INTEL_PT_TRACESTOP:
1996	case INTEL_PT_PIP:
1997	case INTEL_PT_OVF:
1998	case INTEL_PT_MNT:
1999	case INTEL_PT_PTWRITE:
2000	case INTEL_PT_PTWRITE_IP:
2001	case INTEL_PT_EXSTOP:
2002	case INTEL_PT_EXSTOP_IP:
2003	case INTEL_PT_MWAIT:
2004	case INTEL_PT_PWRE:
2005	case INTEL_PT_PWRX:
2006	case INTEL_PT_BBP:
2007	case INTEL_PT_BIP:
2008	case INTEL_PT_BEP:
2009	case INTEL_PT_BEP_IP:
 
 
 
2010	default:
2011		return HOP_PROCESS;
2012	}
2013}
2014
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2015static int intel_pt_walk_trace(struct intel_pt_decoder *decoder)
2016{
 
2017	bool no_tip = false;
2018	int err;
2019
2020	while (1) {
2021		err = intel_pt_get_next_packet(decoder);
2022		if (err)
2023			return err;
2024next:
 
 
 
 
 
 
 
2025		if (decoder->hop) {
2026			switch (intel_pt_hop_trace(decoder, &no_tip, &err)) {
2027			case HOP_IGNORE:
2028				continue;
2029			case HOP_RETURN:
2030				return err;
2031			case HOP_AGAIN:
2032				goto next;
2033			default:
2034				break;
2035			}
2036		}
2037
2038		switch (decoder->packet.type) {
2039		case INTEL_PT_TNT:
2040			if (!decoder->packet.count)
2041				break;
2042			decoder->tnt = decoder->packet;
2043			decoder->pkt_state = INTEL_PT_STATE_TNT;
2044			err = intel_pt_walk_tnt(decoder);
2045			if (err == -EAGAIN)
2046				break;
2047			return err;
2048
2049		case INTEL_PT_TIP_PGD:
2050			if (decoder->packet.count != 0)
2051				intel_pt_set_last_ip(decoder);
2052			decoder->pkt_state = INTEL_PT_STATE_TIP_PGD;
2053			return intel_pt_walk_tip(decoder);
2054
2055		case INTEL_PT_TIP_PGE: {
2056			decoder->pge = true;
 
2057			intel_pt_mtc_cyc_cnt_pge(decoder);
 
2058			if (decoder->packet.count == 0) {
2059				intel_pt_log_at("Skipping zero TIP.PGE",
2060						decoder->pos);
2061				break;
2062			}
 
2063			intel_pt_set_ip(decoder);
2064			decoder->state.from_ip = 0;
2065			decoder->state.to_ip = decoder->ip;
2066			decoder->state.type |= INTEL_PT_TRACE_BEGIN;
2067			/*
2068			 * In hop mode, resample to get the to_ip as an
2069			 * "instruction" sample.
2070			 */
2071			if (decoder->hop)
2072				decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
2073			return 0;
2074		}
2075
2076		case INTEL_PT_OVF:
2077			return intel_pt_overflow(decoder);
2078
2079		case INTEL_PT_TIP:
2080			if (decoder->packet.count != 0)
2081				intel_pt_set_last_ip(decoder);
2082			decoder->pkt_state = INTEL_PT_STATE_TIP;
2083			return intel_pt_walk_tip(decoder);
2084
2085		case INTEL_PT_FUP:
2086			if (decoder->packet.count == 0) {
2087				intel_pt_log_at("Skipping zero FUP",
2088						decoder->pos);
2089				no_tip = false;
2090				break;
2091			}
2092			intel_pt_set_last_ip(decoder);
2093			if (!decoder->branch_enable) {
2094				decoder->ip = decoder->last_ip;
2095				if (intel_pt_fup_event(decoder))
2096					return 0;
2097				no_tip = false;
2098				break;
2099			}
2100			if (decoder->set_fup_mwait)
2101				no_tip = true;
2102			if (no_tip)
2103				decoder->pkt_state = INTEL_PT_STATE_FUP_NO_TIP;
2104			else
2105				decoder->pkt_state = INTEL_PT_STATE_FUP;
2106			err = intel_pt_walk_fup(decoder);
2107			if (err != -EAGAIN)
2108				return err;
2109			if (no_tip) {
2110				no_tip = false;
2111				break;
2112			}
2113			return intel_pt_walk_fup_tip(decoder);
2114
2115		case INTEL_PT_TRACESTOP:
2116			decoder->pge = false;
2117			decoder->continuous_period = false;
2118			intel_pt_clear_tx_flags(decoder);
2119			decoder->have_tma = false;
2120			break;
2121
2122		case INTEL_PT_PSB:
2123			decoder->last_ip = 0;
2124			decoder->have_last_ip = true;
2125			intel_pt_clear_stack(&decoder->stack);
2126			err = intel_pt_walk_psbend(decoder);
 
2127			if (err == -EAGAIN)
2128				goto next;
2129			if (err)
2130				return err;
2131			/*
2132			 * PSB+ CBR will not have changed but cater for the
2133			 * possibility of another CBR change that gets caught up
2134			 * in the PSB+.
2135			 */
2136			if (decoder->cbr != decoder->cbr_seen) {
2137				decoder->state.type = 0;
2138				return 0;
2139			}
2140			break;
2141
2142		case INTEL_PT_PIP:
2143			decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
2144			break;
2145
2146		case INTEL_PT_MTC:
2147			intel_pt_calc_mtc_timestamp(decoder);
2148			if (decoder->period_type != INTEL_PT_PERIOD_MTC)
2149				break;
2150			/*
2151			 * Ensure that there has been an instruction since the
2152			 * last MTC.
2153			 */
2154			if (!decoder->mtc_insn)
2155				break;
2156			decoder->mtc_insn = false;
2157			/* Ensure that there is a timestamp */
2158			if (!decoder->timestamp)
2159				break;
2160			decoder->state.type = INTEL_PT_INSTRUCTION;
2161			decoder->state.from_ip = decoder->ip;
2162			decoder->state.to_ip = 0;
2163			decoder->mtc_insn = false;
2164			return 0;
2165
2166		case INTEL_PT_TSC:
2167			intel_pt_calc_tsc_timestamp(decoder);
2168			break;
2169
2170		case INTEL_PT_TMA:
2171			intel_pt_calc_tma(decoder);
2172			break;
2173
2174		case INTEL_PT_CYC:
2175			intel_pt_calc_cyc_timestamp(decoder);
2176			break;
2177
2178		case INTEL_PT_CBR:
2179			intel_pt_calc_cbr(decoder);
2180			if (decoder->cbr != decoder->cbr_seen) {
2181				decoder->state.type = 0;
2182				return 0;
2183			}
2184			break;
2185
2186		case INTEL_PT_MODE_EXEC:
2187			decoder->exec_mode = decoder->packet.payload;
2188			break;
 
 
 
 
 
 
 
2189
2190		case INTEL_PT_MODE_TSX:
2191			/* MODE_TSX need not be followed by FUP */
2192			if (!decoder->pge || decoder->in_psb) {
2193				intel_pt_update_in_tx(decoder);
2194				break;
2195			}
2196			err = intel_pt_mode_tsx(decoder, &no_tip);
2197			if (err)
2198				return err;
2199			goto next;
2200
2201		case INTEL_PT_BAD: /* Does not happen */
2202			return intel_pt_bug(decoder);
2203
2204		case INTEL_PT_PSBEND:
2205		case INTEL_PT_VMCS:
2206		case INTEL_PT_MNT:
2207		case INTEL_PT_PAD:
2208			break;
2209
2210		case INTEL_PT_PTWRITE_IP:
2211			decoder->fup_ptw_payload = decoder->packet.payload;
2212			err = intel_pt_get_next_packet(decoder);
2213			if (err)
2214				return err;
2215			if (decoder->packet.type == INTEL_PT_FUP) {
2216				decoder->set_fup_ptw = true;
2217				no_tip = true;
2218			} else {
2219				intel_pt_log_at("ERROR: Missing FUP after PTWRITE",
2220						decoder->pos);
2221			}
2222			goto next;
2223
2224		case INTEL_PT_PTWRITE:
2225			decoder->state.type = INTEL_PT_PTW;
2226			decoder->state.from_ip = decoder->ip;
2227			decoder->state.to_ip = 0;
2228			decoder->state.ptw_payload = decoder->packet.payload;
2229			return 0;
2230
2231		case INTEL_PT_MWAIT:
2232			decoder->fup_mwait_payload = decoder->packet.payload;
2233			decoder->set_fup_mwait = true;
2234			break;
2235
2236		case INTEL_PT_PWRE:
2237			if (decoder->set_fup_mwait) {
2238				decoder->fup_pwre_payload =
2239							decoder->packet.payload;
2240				decoder->set_fup_pwre = true;
2241				break;
2242			}
2243			decoder->state.type = INTEL_PT_PWR_ENTRY;
2244			decoder->state.from_ip = decoder->ip;
2245			decoder->state.to_ip = 0;
2246			decoder->state.pwrx_payload = decoder->packet.payload;
2247			return 0;
2248
2249		case INTEL_PT_EXSTOP_IP:
2250			err = intel_pt_get_next_packet(decoder);
2251			if (err)
2252				return err;
2253			if (decoder->packet.type == INTEL_PT_FUP) {
2254				decoder->set_fup_exstop = true;
2255				no_tip = true;
2256			} else {
2257				intel_pt_log_at("ERROR: Missing FUP after EXSTOP",
2258						decoder->pos);
2259			}
2260			goto next;
2261
2262		case INTEL_PT_EXSTOP:
2263			decoder->state.type = INTEL_PT_EX_STOP;
2264			decoder->state.from_ip = decoder->ip;
2265			decoder->state.to_ip = 0;
2266			return 0;
2267
2268		case INTEL_PT_PWRX:
2269			decoder->state.type = INTEL_PT_PWR_EXIT;
2270			decoder->state.from_ip = decoder->ip;
2271			decoder->state.to_ip = 0;
2272			decoder->state.pwrx_payload = decoder->packet.payload;
2273			return 0;
2274
2275		case INTEL_PT_BBP:
2276			intel_pt_bbp(decoder);
2277			break;
2278
2279		case INTEL_PT_BIP:
2280			intel_pt_bip(decoder);
2281			break;
2282
2283		case INTEL_PT_BEP:
2284			decoder->state.type = INTEL_PT_BLK_ITEMS;
2285			decoder->state.from_ip = decoder->ip;
2286			decoder->state.to_ip = 0;
2287			return 0;
2288
2289		case INTEL_PT_BEP_IP:
2290			err = intel_pt_get_next_packet(decoder);
2291			if (err)
2292				return err;
2293			if (decoder->packet.type == INTEL_PT_FUP) {
2294				decoder->set_fup_bep = true;
2295				no_tip = true;
2296			} else {
2297				intel_pt_log_at("ERROR: Missing FUP after BEP",
2298						decoder->pos);
2299			}
2300			goto next;
2301
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2302		default:
2303			return intel_pt_bug(decoder);
2304		}
2305	}
2306}
2307
2308static inline bool intel_pt_have_ip(struct intel_pt_decoder *decoder)
2309{
2310	return decoder->packet.count &&
2311	       (decoder->have_last_ip || decoder->packet.count == 3 ||
2312		decoder->packet.count == 6);
2313}
2314
2315/* Walk PSB+ packets to get in sync. */
2316static int intel_pt_walk_psb(struct intel_pt_decoder *decoder)
2317{
2318	int err;
2319
2320	decoder->in_psb = true;
2321
2322	while (1) {
2323		err = intel_pt_get_next_packet(decoder);
2324		if (err)
2325			goto out;
2326
2327		switch (decoder->packet.type) {
2328		case INTEL_PT_TIP_PGD:
2329			decoder->continuous_period = false;
2330			__fallthrough;
2331		case INTEL_PT_TIP_PGE:
2332		case INTEL_PT_TIP:
2333		case INTEL_PT_PTWRITE:
2334		case INTEL_PT_PTWRITE_IP:
2335		case INTEL_PT_EXSTOP:
2336		case INTEL_PT_EXSTOP_IP:
2337		case INTEL_PT_MWAIT:
2338		case INTEL_PT_PWRE:
2339		case INTEL_PT_PWRX:
2340		case INTEL_PT_BBP:
2341		case INTEL_PT_BIP:
2342		case INTEL_PT_BEP:
2343		case INTEL_PT_BEP_IP:
 
 
 
2344			intel_pt_log("ERROR: Unexpected packet\n");
2345			err = -ENOENT;
2346			goto out;
2347
2348		case INTEL_PT_FUP:
2349			decoder->pge = true;
2350			if (intel_pt_have_ip(decoder)) {
2351				uint64_t current_ip = decoder->ip;
2352
2353				intel_pt_set_ip(decoder);
 
2354				if (current_ip)
2355					intel_pt_log_to("Setting IP",
2356							decoder->ip);
2357			}
2358			break;
2359
2360		case INTEL_PT_MTC:
2361			intel_pt_calc_mtc_timestamp(decoder);
2362			break;
2363
2364		case INTEL_PT_TSC:
2365			intel_pt_calc_tsc_timestamp(decoder);
2366			break;
2367
2368		case INTEL_PT_TMA:
2369			intel_pt_calc_tma(decoder);
2370			break;
2371
2372		case INTEL_PT_CYC:
2373			intel_pt_calc_cyc_timestamp(decoder);
2374			break;
2375
2376		case INTEL_PT_CBR:
2377			intel_pt_calc_cbr(decoder);
2378			break;
2379
2380		case INTEL_PT_PIP:
2381			decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
2382			break;
2383
2384		case INTEL_PT_MODE_EXEC:
2385			decoder->exec_mode = decoder->packet.payload;
2386			break;
2387
2388		case INTEL_PT_MODE_TSX:
2389			intel_pt_update_in_tx(decoder);
2390			break;
2391
2392		case INTEL_PT_TRACESTOP:
2393			decoder->pge = false;
2394			decoder->continuous_period = false;
2395			intel_pt_clear_tx_flags(decoder);
2396			__fallthrough;
2397
2398		case INTEL_PT_TNT:
2399			decoder->have_tma = false;
2400			intel_pt_log("ERROR: Unexpected packet\n");
2401			if (decoder->ip)
2402				decoder->pkt_state = INTEL_PT_STATE_ERR4;
2403			else
2404				decoder->pkt_state = INTEL_PT_STATE_ERR3;
2405			err = -ENOENT;
2406			goto out;
2407
2408		case INTEL_PT_BAD: /* Does not happen */
2409			err = intel_pt_bug(decoder);
2410			goto out;
2411
2412		case INTEL_PT_OVF:
2413			err = intel_pt_overflow(decoder);
2414			goto out;
2415
2416		case INTEL_PT_PSBEND:
2417			err = 0;
2418			goto out;
2419
2420		case INTEL_PT_PSB:
2421		case INTEL_PT_VMCS:
2422		case INTEL_PT_MNT:
2423		case INTEL_PT_PAD:
2424		default:
2425			break;
2426		}
2427	}
2428out:
2429	decoder->in_psb = false;
2430
2431	return err;
2432}
2433
2434static int intel_pt_walk_to_ip(struct intel_pt_decoder *decoder)
2435{
2436	int err;
2437
2438	while (1) {
2439		err = intel_pt_get_next_packet(decoder);
2440		if (err)
2441			return err;
2442
2443		switch (decoder->packet.type) {
2444		case INTEL_PT_TIP_PGD:
2445			decoder->continuous_period = false;
2446			decoder->pge = false;
2447			if (intel_pt_have_ip(decoder))
2448				intel_pt_set_ip(decoder);
2449			if (!decoder->ip)
2450				break;
2451			decoder->state.type |= INTEL_PT_TRACE_END;
2452			return 0;
2453
2454		case INTEL_PT_TIP_PGE:
2455			decoder->pge = true;
2456			intel_pt_mtc_cyc_cnt_pge(decoder);
2457			if (intel_pt_have_ip(decoder))
2458				intel_pt_set_ip(decoder);
2459			if (!decoder->ip)
2460				break;
2461			decoder->state.type |= INTEL_PT_TRACE_BEGIN;
2462			return 0;
2463
2464		case INTEL_PT_TIP:
2465			decoder->pge = true;
2466			if (intel_pt_have_ip(decoder))
2467				intel_pt_set_ip(decoder);
2468			if (!decoder->ip)
2469				break;
2470			return 0;
2471
2472		case INTEL_PT_FUP:
2473			if (intel_pt_have_ip(decoder))
2474				intel_pt_set_ip(decoder);
2475			if (decoder->ip)
2476				return 0;
2477			break;
2478
2479		case INTEL_PT_MTC:
2480			intel_pt_calc_mtc_timestamp(decoder);
2481			break;
2482
2483		case INTEL_PT_TSC:
2484			intel_pt_calc_tsc_timestamp(decoder);
2485			break;
2486
2487		case INTEL_PT_TMA:
2488			intel_pt_calc_tma(decoder);
2489			break;
2490
2491		case INTEL_PT_CYC:
2492			intel_pt_calc_cyc_timestamp(decoder);
2493			break;
2494
2495		case INTEL_PT_CBR:
2496			intel_pt_calc_cbr(decoder);
2497			break;
2498
2499		case INTEL_PT_PIP:
2500			decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
2501			break;
2502
2503		case INTEL_PT_MODE_EXEC:
2504			decoder->exec_mode = decoder->packet.payload;
2505			break;
2506
2507		case INTEL_PT_MODE_TSX:
2508			intel_pt_update_in_tx(decoder);
2509			break;
2510
2511		case INTEL_PT_OVF:
2512			return intel_pt_overflow(decoder);
2513
2514		case INTEL_PT_BAD: /* Does not happen */
2515			return intel_pt_bug(decoder);
2516
2517		case INTEL_PT_TRACESTOP:
2518			decoder->pge = false;
2519			decoder->continuous_period = false;
2520			intel_pt_clear_tx_flags(decoder);
2521			decoder->have_tma = false;
2522			break;
2523
2524		case INTEL_PT_PSB:
 
 
2525			decoder->last_ip = 0;
2526			decoder->have_last_ip = true;
2527			intel_pt_clear_stack(&decoder->stack);
2528			err = intel_pt_walk_psb(decoder);
2529			if (err)
2530				return err;
2531			if (decoder->ip) {
2532				/* Do not have a sample */
2533				decoder->state.type = 0;
2534				return 0;
2535			}
2536			break;
2537
2538		case INTEL_PT_TNT:
2539		case INTEL_PT_PSBEND:
2540		case INTEL_PT_VMCS:
2541		case INTEL_PT_MNT:
2542		case INTEL_PT_PAD:
2543		case INTEL_PT_PTWRITE:
2544		case INTEL_PT_PTWRITE_IP:
2545		case INTEL_PT_EXSTOP:
2546		case INTEL_PT_EXSTOP_IP:
2547		case INTEL_PT_MWAIT:
2548		case INTEL_PT_PWRE:
2549		case INTEL_PT_PWRX:
2550		case INTEL_PT_BBP:
2551		case INTEL_PT_BIP:
2552		case INTEL_PT_BEP:
2553		case INTEL_PT_BEP_IP:
 
 
 
2554		default:
2555			break;
2556		}
2557	}
2558}
2559
2560static int intel_pt_sync_ip(struct intel_pt_decoder *decoder)
2561{
2562	int err;
2563
2564	decoder->set_fup_tx_flags = false;
2565	decoder->set_fup_ptw = false;
2566	decoder->set_fup_mwait = false;
2567	decoder->set_fup_pwre = false;
2568	decoder->set_fup_exstop = false;
2569	decoder->set_fup_bep = false;
2570
2571	if (!decoder->branch_enable) {
2572		decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2573		decoder->overflow = false;
2574		decoder->state.type = 0; /* Do not have a sample */
2575		return 0;
2576	}
2577
2578	intel_pt_log("Scanning for full IP\n");
2579	err = intel_pt_walk_to_ip(decoder);
2580	if (err)
2581		return err;
2582
2583	/* In hop mode, resample to get the to_ip as an "instruction" sample */
2584	if (decoder->hop)
2585		decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
2586	else
2587		decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2588	decoder->overflow = false;
2589
2590	decoder->state.from_ip = 0;
2591	decoder->state.to_ip = decoder->ip;
2592	intel_pt_log_to("Setting IP", decoder->ip);
2593
2594	return 0;
2595}
2596
2597static int intel_pt_part_psb(struct intel_pt_decoder *decoder)
2598{
2599	const unsigned char *end = decoder->buf + decoder->len;
2600	size_t i;
2601
2602	for (i = INTEL_PT_PSB_LEN - 1; i; i--) {
2603		if (i > decoder->len)
2604			continue;
2605		if (!memcmp(end - i, INTEL_PT_PSB_STR, i))
2606			return i;
2607	}
2608	return 0;
2609}
2610
2611static int intel_pt_rest_psb(struct intel_pt_decoder *decoder, int part_psb)
2612{
2613	size_t rest_psb = INTEL_PT_PSB_LEN - part_psb;
2614	const char *psb = INTEL_PT_PSB_STR;
2615
2616	if (rest_psb > decoder->len ||
2617	    memcmp(decoder->buf, psb + part_psb, rest_psb))
2618		return 0;
2619
2620	return rest_psb;
2621}
2622
2623static int intel_pt_get_split_psb(struct intel_pt_decoder *decoder,
2624				  int part_psb)
2625{
2626	int rest_psb, ret;
2627
2628	decoder->pos += decoder->len;
2629	decoder->len = 0;
2630
2631	ret = intel_pt_get_next_data(decoder, false);
2632	if (ret)
2633		return ret;
2634
2635	rest_psb = intel_pt_rest_psb(decoder, part_psb);
2636	if (!rest_psb)
2637		return 0;
2638
2639	decoder->pos -= part_psb;
2640	decoder->next_buf = decoder->buf + rest_psb;
2641	decoder->next_len = decoder->len - rest_psb;
2642	memcpy(decoder->temp_buf, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
2643	decoder->buf = decoder->temp_buf;
2644	decoder->len = INTEL_PT_PSB_LEN;
2645
2646	return 0;
2647}
2648
2649static int intel_pt_scan_for_psb(struct intel_pt_decoder *decoder)
2650{
2651	unsigned char *next;
2652	int ret;
2653
2654	intel_pt_log("Scanning for PSB\n");
2655	while (1) {
2656		if (!decoder->len) {
2657			ret = intel_pt_get_next_data(decoder, false);
2658			if (ret)
2659				return ret;
2660		}
2661
2662		next = memmem(decoder->buf, decoder->len, INTEL_PT_PSB_STR,
2663			      INTEL_PT_PSB_LEN);
2664		if (!next) {
2665			int part_psb;
2666
2667			part_psb = intel_pt_part_psb(decoder);
2668			if (part_psb) {
2669				ret = intel_pt_get_split_psb(decoder, part_psb);
2670				if (ret)
2671					return ret;
2672			} else {
2673				decoder->pos += decoder->len;
2674				decoder->len = 0;
2675			}
2676			continue;
2677		}
2678
2679		decoder->pkt_step = next - decoder->buf;
2680		return intel_pt_get_next_packet(decoder);
2681	}
2682}
2683
2684static int intel_pt_sync(struct intel_pt_decoder *decoder)
2685{
2686	int err;
2687
2688	decoder->pge = false;
2689	decoder->continuous_period = false;
2690	decoder->have_last_ip = false;
2691	decoder->last_ip = 0;
 
2692	decoder->ip = 0;
2693	intel_pt_clear_stack(&decoder->stack);
2694
2695leap:
2696	err = intel_pt_scan_for_psb(decoder);
2697	if (err)
2698		return err;
2699
 
 
 
 
 
 
 
 
 
2700	decoder->have_last_ip = true;
2701	decoder->pkt_state = INTEL_PT_STATE_NO_IP;
2702
2703	err = intel_pt_walk_psb(decoder);
2704	if (err)
2705		return err;
2706
 
 
 
 
2707	if (decoder->ip) {
2708		decoder->state.type = 0; /* Do not have a sample */
2709		/*
2710		 * In hop mode, resample to get the PSB FUP ip as an
2711		 * "instruction" sample.
2712		 */
2713		if (decoder->hop)
2714			decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
2715		else
2716			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2717	} else if (decoder->leap) {
2718		/*
2719		 * In leap mode, only PSB+ is decoded, so keeping leaping to the
2720		 * next PSB until there is an ip.
2721		 */
2722		goto leap;
2723	} else {
2724		return intel_pt_sync_ip(decoder);
2725	}
2726
2727	return 0;
2728}
2729
2730static uint64_t intel_pt_est_timestamp(struct intel_pt_decoder *decoder)
2731{
2732	uint64_t est = decoder->sample_insn_cnt << 1;
2733
2734	if (!decoder->cbr || !decoder->max_non_turbo_ratio)
2735		goto out;
2736
2737	est *= decoder->max_non_turbo_ratio;
2738	est /= decoder->cbr;
2739out:
2740	return decoder->sample_timestamp + est;
2741}
2742
2743const struct intel_pt_state *intel_pt_decode(struct intel_pt_decoder *decoder)
2744{
2745	int err;
2746
2747	do {
2748		decoder->state.type = INTEL_PT_BRANCH;
2749		decoder->state.flags = 0;
2750
2751		switch (decoder->pkt_state) {
2752		case INTEL_PT_STATE_NO_PSB:
2753			err = intel_pt_sync(decoder);
2754			break;
2755		case INTEL_PT_STATE_NO_IP:
2756			decoder->have_last_ip = false;
2757			decoder->last_ip = 0;
2758			decoder->ip = 0;
2759			__fallthrough;
2760		case INTEL_PT_STATE_ERR_RESYNC:
2761			err = intel_pt_sync_ip(decoder);
2762			break;
2763		case INTEL_PT_STATE_IN_SYNC:
2764			err = intel_pt_walk_trace(decoder);
2765			break;
2766		case INTEL_PT_STATE_TNT:
2767		case INTEL_PT_STATE_TNT_CONT:
2768			err = intel_pt_walk_tnt(decoder);
2769			if (err == -EAGAIN)
2770				err = intel_pt_walk_trace(decoder);
2771			break;
2772		case INTEL_PT_STATE_TIP:
2773		case INTEL_PT_STATE_TIP_PGD:
2774			err = intel_pt_walk_tip(decoder);
2775			break;
2776		case INTEL_PT_STATE_FUP:
2777			err = intel_pt_walk_fup(decoder);
2778			if (err == -EAGAIN)
2779				err = intel_pt_walk_fup_tip(decoder);
2780			break;
2781		case INTEL_PT_STATE_FUP_NO_TIP:
2782			err = intel_pt_walk_fup(decoder);
2783			if (err == -EAGAIN)
2784				err = intel_pt_walk_trace(decoder);
2785			break;
 
 
 
2786		case INTEL_PT_STATE_RESAMPLE:
2787			err = intel_pt_resample(decoder);
2788			break;
 
 
 
2789		default:
2790			err = intel_pt_bug(decoder);
2791			break;
2792		}
2793	} while (err == -ENOLINK);
2794
2795	if (err) {
2796		decoder->state.err = intel_pt_ext_err(err);
2797		decoder->state.from_ip = decoder->ip;
 
2798		intel_pt_update_sample_time(decoder);
2799		decoder->sample_tot_cyc_cnt = decoder->tot_cyc_cnt;
 
2800	} else {
2801		decoder->state.err = 0;
2802		if (decoder->cbr != decoder->cbr_seen) {
2803			decoder->cbr_seen = decoder->cbr;
2804			if (!decoder->state.type) {
2805				decoder->state.from_ip = decoder->ip;
2806				decoder->state.to_ip = 0;
2807			}
2808			decoder->state.type |= INTEL_PT_CBR_CHG;
2809			decoder->state.cbr_payload = decoder->cbr_payload;
2810			decoder->state.cbr = decoder->cbr;
2811		}
2812		if (intel_pt_sample_time(decoder->pkt_state)) {
2813			intel_pt_update_sample_time(decoder);
2814			if (decoder->sample_cyc)
2815				decoder->sample_tot_cyc_cnt = decoder->tot_cyc_cnt;
 
 
 
2816		}
 
 
 
 
 
 
2817	}
2818
 
 
 
 
 
 
 
 
2819	decoder->state.timestamp = decoder->sample_timestamp;
2820	decoder->state.est_timestamp = intel_pt_est_timestamp(decoder);
2821	decoder->state.cr3 = decoder->cr3;
2822	decoder->state.tot_insn_cnt = decoder->tot_insn_cnt;
2823	decoder->state.tot_cyc_cnt = decoder->sample_tot_cyc_cnt;
2824
2825	return &decoder->state;
2826}
2827
2828/**
2829 * intel_pt_next_psb - move buffer pointer to the start of the next PSB packet.
2830 * @buf: pointer to buffer pointer
2831 * @len: size of buffer
2832 *
2833 * Updates the buffer pointer to point to the start of the next PSB packet if
2834 * there is one, otherwise the buffer pointer is unchanged.  If @buf is updated,
2835 * @len is adjusted accordingly.
2836 *
2837 * Return: %true if a PSB packet is found, %false otherwise.
2838 */
2839static bool intel_pt_next_psb(unsigned char **buf, size_t *len)
2840{
2841	unsigned char *next;
2842
2843	next = memmem(*buf, *len, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
2844	if (next) {
2845		*len -= next - *buf;
2846		*buf = next;
2847		return true;
2848	}
2849	return false;
2850}
2851
2852/**
2853 * intel_pt_step_psb - move buffer pointer to the start of the following PSB
2854 *                     packet.
2855 * @buf: pointer to buffer pointer
2856 * @len: size of buffer
2857 *
2858 * Updates the buffer pointer to point to the start of the following PSB packet
2859 * (skipping the PSB at @buf itself) if there is one, otherwise the buffer
2860 * pointer is unchanged.  If @buf is updated, @len is adjusted accordingly.
2861 *
2862 * Return: %true if a PSB packet is found, %false otherwise.
2863 */
2864static bool intel_pt_step_psb(unsigned char **buf, size_t *len)
2865{
2866	unsigned char *next;
2867
2868	if (!*len)
2869		return false;
2870
2871	next = memmem(*buf + 1, *len - 1, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
2872	if (next) {
2873		*len -= next - *buf;
2874		*buf = next;
2875		return true;
2876	}
2877	return false;
2878}
2879
2880/**
2881 * intel_pt_last_psb - find the last PSB packet in a buffer.
2882 * @buf: buffer
2883 * @len: size of buffer
2884 *
2885 * This function finds the last PSB in a buffer.
2886 *
2887 * Return: A pointer to the last PSB in @buf if found, %NULL otherwise.
2888 */
2889static unsigned char *intel_pt_last_psb(unsigned char *buf, size_t len)
2890{
2891	const char *n = INTEL_PT_PSB_STR;
2892	unsigned char *p;
2893	size_t k;
2894
2895	if (len < INTEL_PT_PSB_LEN)
2896		return NULL;
2897
2898	k = len - INTEL_PT_PSB_LEN + 1;
2899	while (1) {
2900		p = memrchr(buf, n[0], k);
2901		if (!p)
2902			return NULL;
2903		if (!memcmp(p + 1, n + 1, INTEL_PT_PSB_LEN - 1))
2904			return p;
2905		k = p - buf;
2906		if (!k)
2907			return NULL;
2908	}
2909}
2910
2911/**
2912 * intel_pt_next_tsc - find and return next TSC.
2913 * @buf: buffer
2914 * @len: size of buffer
2915 * @tsc: TSC value returned
2916 * @rem: returns remaining size when TSC is found
2917 *
2918 * Find a TSC packet in @buf and return the TSC value.  This function assumes
2919 * that @buf starts at a PSB and that PSB+ will contain TSC and so stops if a
2920 * PSBEND packet is found.
2921 *
2922 * Return: %true if TSC is found, false otherwise.
2923 */
2924static bool intel_pt_next_tsc(unsigned char *buf, size_t len, uint64_t *tsc,
2925			      size_t *rem)
2926{
2927	enum intel_pt_pkt_ctx ctx = INTEL_PT_NO_CTX;
2928	struct intel_pt_pkt packet;
2929	int ret;
2930
2931	while (len) {
2932		ret = intel_pt_get_packet(buf, len, &packet, &ctx);
2933		if (ret <= 0)
2934			return false;
2935		if (packet.type == INTEL_PT_TSC) {
2936			*tsc = packet.payload;
2937			*rem = len;
2938			return true;
2939		}
2940		if (packet.type == INTEL_PT_PSBEND)
2941			return false;
2942		buf += ret;
2943		len -= ret;
2944	}
2945	return false;
2946}
2947
2948/**
2949 * intel_pt_tsc_cmp - compare 7-byte TSCs.
2950 * @tsc1: first TSC to compare
2951 * @tsc2: second TSC to compare
2952 *
2953 * This function compares 7-byte TSC values allowing for the possibility that
2954 * TSC wrapped around.  Generally it is not possible to know if TSC has wrapped
2955 * around so for that purpose this function assumes the absolute difference is
2956 * less than half the maximum difference.
2957 *
2958 * Return: %-1 if @tsc1 is before @tsc2, %0 if @tsc1 == @tsc2, %1 if @tsc1 is
2959 * after @tsc2.
2960 */
2961static int intel_pt_tsc_cmp(uint64_t tsc1, uint64_t tsc2)
2962{
2963	const uint64_t halfway = (1ULL << 55);
2964
2965	if (tsc1 == tsc2)
2966		return 0;
2967
2968	if (tsc1 < tsc2) {
2969		if (tsc2 - tsc1 < halfway)
2970			return -1;
2971		else
2972			return 1;
2973	} else {
2974		if (tsc1 - tsc2 < halfway)
2975			return 1;
2976		else
2977			return -1;
2978	}
2979}
2980
2981#define MAX_PADDING (PERF_AUXTRACE_RECORD_ALIGNMENT - 1)
2982
2983/**
2984 * adj_for_padding - adjust overlap to account for padding.
2985 * @buf_b: second buffer
2986 * @buf_a: first buffer
2987 * @len_a: size of first buffer
2988 *
2989 * @buf_a might have up to 7 bytes of padding appended. Adjust the overlap
2990 * accordingly.
2991 *
2992 * Return: A pointer into @buf_b from where non-overlapped data starts
2993 */
2994static unsigned char *adj_for_padding(unsigned char *buf_b,
2995				      unsigned char *buf_a, size_t len_a)
2996{
2997	unsigned char *p = buf_b - MAX_PADDING;
2998	unsigned char *q = buf_a + len_a - MAX_PADDING;
2999	int i;
3000
3001	for (i = MAX_PADDING; i; i--, p++, q++) {
3002		if (*p != *q)
3003			break;
3004	}
3005
3006	return p;
3007}
3008
3009/**
3010 * intel_pt_find_overlap_tsc - determine start of non-overlapped trace data
3011 *                             using TSC.
3012 * @buf_a: first buffer
3013 * @len_a: size of first buffer
3014 * @buf_b: second buffer
3015 * @len_b: size of second buffer
3016 * @consecutive: returns true if there is data in buf_b that is consecutive
3017 *               to buf_a
 
3018 *
3019 * If the trace contains TSC we can look at the last TSC of @buf_a and the
3020 * first TSC of @buf_b in order to determine if the buffers overlap, and then
3021 * walk forward in @buf_b until a later TSC is found.  A precondition is that
3022 * @buf_a and @buf_b are positioned at a PSB.
3023 *
3024 * Return: A pointer into @buf_b from where non-overlapped data starts, or
3025 * @buf_b + @len_b if there is no non-overlapped data.
3026 */
3027static unsigned char *intel_pt_find_overlap_tsc(unsigned char *buf_a,
3028						size_t len_a,
3029						unsigned char *buf_b,
3030						size_t len_b, bool *consecutive)
 
3031{
3032	uint64_t tsc_a, tsc_b;
3033	unsigned char *p;
3034	size_t len, rem_a, rem_b;
3035
3036	p = intel_pt_last_psb(buf_a, len_a);
3037	if (!p)
3038		return buf_b; /* No PSB in buf_a => no overlap */
3039
3040	len = len_a - (p - buf_a);
3041	if (!intel_pt_next_tsc(p, len, &tsc_a, &rem_a)) {
3042		/* The last PSB+ in buf_a is incomplete, so go back one more */
3043		len_a -= len;
3044		p = intel_pt_last_psb(buf_a, len_a);
3045		if (!p)
3046			return buf_b; /* No full PSB+ => assume no overlap */
3047		len = len_a - (p - buf_a);
3048		if (!intel_pt_next_tsc(p, len, &tsc_a, &rem_a))
3049			return buf_b; /* No TSC in buf_a => assume no overlap */
3050	}
3051
3052	while (1) {
3053		/* Ignore PSB+ with no TSC */
3054		if (intel_pt_next_tsc(buf_b, len_b, &tsc_b, &rem_b)) {
3055			int cmp = intel_pt_tsc_cmp(tsc_a, tsc_b);
3056
3057			/* Same TSC, so buffers are consecutive */
3058			if (!cmp && rem_b >= rem_a) {
3059				unsigned char *start;
3060
3061				*consecutive = true;
3062				start = buf_b + len_b - (rem_b - rem_a);
3063				return adj_for_padding(start, buf_a, len_a);
3064			}
3065			if (cmp < 0)
3066				return buf_b; /* tsc_a < tsc_b => no overlap */
3067		}
3068
3069		if (!intel_pt_step_psb(&buf_b, &len_b))
3070			return buf_b + len_b; /* No PSB in buf_b => no data */
3071	}
3072}
3073
3074/**
3075 * intel_pt_find_overlap - determine start of non-overlapped trace data.
3076 * @buf_a: first buffer
3077 * @len_a: size of first buffer
3078 * @buf_b: second buffer
3079 * @len_b: size of second buffer
3080 * @have_tsc: can use TSC packets to detect overlap
3081 * @consecutive: returns true if there is data in buf_b that is consecutive
3082 *               to buf_a
 
3083 *
3084 * When trace samples or snapshots are recorded there is the possibility that
3085 * the data overlaps.  Note that, for the purposes of decoding, data is only
3086 * useful if it begins with a PSB packet.
3087 *
3088 * Return: A pointer into @buf_b from where non-overlapped data starts, or
3089 * @buf_b + @len_b if there is no non-overlapped data.
3090 */
3091unsigned char *intel_pt_find_overlap(unsigned char *buf_a, size_t len_a,
3092				     unsigned char *buf_b, size_t len_b,
3093				     bool have_tsc, bool *consecutive)
 
3094{
3095	unsigned char *found;
3096
3097	/* Buffer 'b' must start at PSB so throw away everything before that */
3098	if (!intel_pt_next_psb(&buf_b, &len_b))
3099		return buf_b + len_b; /* No PSB */
3100
3101	if (!intel_pt_next_psb(&buf_a, &len_a))
3102		return buf_b; /* No overlap */
3103
3104	if (have_tsc) {
3105		found = intel_pt_find_overlap_tsc(buf_a, len_a, buf_b, len_b,
3106						  consecutive);
3107		if (found)
3108			return found;
3109	}
3110
3111	/*
3112	 * Buffer 'b' cannot end within buffer 'a' so, for comparison purposes,
3113	 * we can ignore the first part of buffer 'a'.
3114	 */
3115	while (len_b < len_a) {
3116		if (!intel_pt_step_psb(&buf_a, &len_a))
3117			return buf_b; /* No overlap */
3118	}
3119
3120	/* Now len_b >= len_a */
3121	while (1) {
3122		/* Potential overlap so check the bytes */
3123		found = memmem(buf_a, len_a, buf_b, len_a);
3124		if (found) {
3125			*consecutive = true;
3126			return adj_for_padding(buf_b + len_a, buf_a, len_a);
3127		}
3128
3129		/* Try again at next PSB in buffer 'a' */
3130		if (!intel_pt_step_psb(&buf_a, &len_a))
3131			return buf_b; /* No overlap */
3132	}
3133}
3134
3135/**
3136 * struct fast_forward_data - data used by intel_pt_ff_cb().
3137 * @timestamp: timestamp to fast forward towards
3138 * @buf_timestamp: buffer timestamp of last buffer with trace data earlier than
3139 *                 the fast forward timestamp.
3140 */
3141struct fast_forward_data {
3142	uint64_t timestamp;
3143	uint64_t buf_timestamp;
3144};
3145
3146/**
3147 * intel_pt_ff_cb - fast forward lookahead callback.
3148 * @buffer: Intel PT trace buffer
3149 * @data: opaque pointer to fast forward data (struct fast_forward_data)
3150 *
3151 * Determine if @buffer trace is past the fast forward timestamp.
3152 *
3153 * Return: 1 (stop lookahead) if @buffer trace is past the fast forward
3154 *         timestamp, and 0 otherwise.
3155 */
3156static int intel_pt_ff_cb(struct intel_pt_buffer *buffer, void *data)
3157{
3158	struct fast_forward_data *d = data;
3159	unsigned char *buf;
3160	uint64_t tsc;
3161	size_t rem;
3162	size_t len;
3163
3164	buf = (unsigned char *)buffer->buf;
3165	len = buffer->len;
3166
3167	if (!intel_pt_next_psb(&buf, &len) ||
3168	    !intel_pt_next_tsc(buf, len, &tsc, &rem))
3169		return 0;
3170
3171	tsc = intel_pt_8b_tsc(tsc, buffer->ref_timestamp);
3172
3173	intel_pt_log("Buffer 1st timestamp " x64_fmt " ref timestamp " x64_fmt "\n",
3174		     tsc, buffer->ref_timestamp);
3175
3176	/*
3177	 * If the buffer contains a timestamp earlier that the fast forward
3178	 * timestamp, then record it, else stop.
3179	 */
3180	if (tsc < d->timestamp)
3181		d->buf_timestamp = buffer->ref_timestamp;
3182	else
3183		return 1;
3184
3185	return 0;
3186}
3187
3188/**
3189 * intel_pt_fast_forward - reposition decoder forwards.
3190 * @decoder: Intel PT decoder
3191 * @timestamp: timestamp to fast forward towards
3192 *
3193 * Reposition decoder at the last PSB with a timestamp earlier than @timestamp.
3194 *
3195 * Return: 0 on success or negative error code on failure.
3196 */
3197int intel_pt_fast_forward(struct intel_pt_decoder *decoder, uint64_t timestamp)
3198{
3199	struct fast_forward_data d = { .timestamp = timestamp };
3200	unsigned char *buf;
3201	size_t len;
3202	int err;
3203
3204	intel_pt_log("Fast forward towards timestamp " x64_fmt "\n", timestamp);
3205
3206	/* Find buffer timestamp of buffer to fast forward to */
3207	err = decoder->lookahead(decoder->data, intel_pt_ff_cb, &d);
3208	if (err < 0)
3209		return err;
3210
3211	/* Walk to buffer with same buffer timestamp */
3212	if (d.buf_timestamp) {
3213		do {
3214			decoder->pos += decoder->len;
3215			decoder->len = 0;
3216			err = intel_pt_get_next_data(decoder, true);
3217			/* -ENOLINK means non-consecutive trace */
3218			if (err && err != -ENOLINK)
3219				return err;
3220		} while (decoder->buf_timestamp != d.buf_timestamp);
3221	}
3222
3223	if (!decoder->buf)
3224		return 0;
3225
3226	buf = (unsigned char *)decoder->buf;
3227	len = decoder->len;
3228
3229	if (!intel_pt_next_psb(&buf, &len))
3230		return 0;
3231
3232	/*
3233	 * Walk PSBs while the PSB timestamp is less than the fast forward
3234	 * timestamp.
3235	 */
3236	do {
3237		uint64_t tsc;
3238		size_t rem;
3239
3240		if (!intel_pt_next_tsc(buf, len, &tsc, &rem))
3241			break;
3242		tsc = intel_pt_8b_tsc(tsc, decoder->buf_timestamp);
3243		/*
3244		 * A TSC packet can slip past MTC packets but, after fast
3245		 * forward, decoding starts at the TSC timestamp. That means
3246		 * the timestamps may not be exactly the same as the timestamps
3247		 * that would have been decoded without fast forward.
3248		 */
3249		if (tsc < timestamp) {
3250			intel_pt_log("Fast forward to next PSB timestamp " x64_fmt "\n", tsc);
3251			decoder->pos += decoder->len - len;
3252			decoder->buf = buf;
3253			decoder->len = len;
3254			intel_pt_reposition(decoder);
3255		} else {
3256			break;
3257		}
3258	} while (intel_pt_step_psb(&buf, &len));
3259
3260	return 0;
3261}