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v4.17
 
   1/*
   2 * intel_pt_decoder.c: Intel Processor Trace support
   3 * Copyright (c) 2013-2014, Intel Corporation.
   4 *
   5 * This program is free software; you can redistribute it and/or modify it
   6 * under the terms and conditions of the GNU General Public License,
   7 * version 2, as published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope it will be useful, but WITHOUT
  10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12 * more details.
  13 *
  14 */
  15
  16#ifndef _GNU_SOURCE
  17#define _GNU_SOURCE
  18#endif
  19#include <stdlib.h>
  20#include <stdbool.h>
  21#include <string.h>
  22#include <errno.h>
  23#include <stdint.h>
  24#include <inttypes.h>
  25#include <linux/compiler.h>
 
 
  26
  27#include "../cache.h"
  28#include "../util.h"
  29
  30#include "intel-pt-insn-decoder.h"
  31#include "intel-pt-pkt-decoder.h"
  32#include "intel-pt-decoder.h"
  33#include "intel-pt-log.h"
  34
 
 
 
 
 
 
 
  35#define INTEL_PT_BLK_SIZE 1024
  36
  37#define BIT63 (((uint64_t)1 << 63))
  38
 
 
 
 
  39#define INTEL_PT_RETURN 1
  40
  41/* Maximum number of loops with no packets consumed i.e. stuck in a loop */
  42#define INTEL_PT_MAX_LOOPS 10000
 
 
 
  43
  44struct intel_pt_blk {
  45	struct intel_pt_blk *prev;
  46	uint64_t ip[INTEL_PT_BLK_SIZE];
  47};
  48
  49struct intel_pt_stack {
  50	struct intel_pt_blk *blk;
  51	struct intel_pt_blk *spare;
  52	int pos;
  53};
  54
 
 
 
 
 
  55enum intel_pt_pkt_state {
  56	INTEL_PT_STATE_NO_PSB,
  57	INTEL_PT_STATE_NO_IP,
  58	INTEL_PT_STATE_ERR_RESYNC,
  59	INTEL_PT_STATE_IN_SYNC,
 
  60	INTEL_PT_STATE_TNT,
  61	INTEL_PT_STATE_TIP,
  62	INTEL_PT_STATE_TIP_PGD,
  63	INTEL_PT_STATE_FUP,
  64	INTEL_PT_STATE_FUP_NO_TIP,
 
 
 
  65};
  66
  67static inline bool intel_pt_sample_time(enum intel_pt_pkt_state pkt_state)
  68{
  69	switch (pkt_state) {
  70	case INTEL_PT_STATE_NO_PSB:
  71	case INTEL_PT_STATE_NO_IP:
  72	case INTEL_PT_STATE_ERR_RESYNC:
  73	case INTEL_PT_STATE_IN_SYNC:
  74	case INTEL_PT_STATE_TNT:
 
 
  75		return true;
 
  76	case INTEL_PT_STATE_TIP:
  77	case INTEL_PT_STATE_TIP_PGD:
  78	case INTEL_PT_STATE_FUP:
  79	case INTEL_PT_STATE_FUP_NO_TIP:
 
  80		return false;
  81	default:
  82		return true;
  83	};
  84}
  85
  86#ifdef INTEL_PT_STRICT
  87#define INTEL_PT_STATE_ERR1	INTEL_PT_STATE_NO_PSB
  88#define INTEL_PT_STATE_ERR2	INTEL_PT_STATE_NO_PSB
  89#define INTEL_PT_STATE_ERR3	INTEL_PT_STATE_NO_PSB
  90#define INTEL_PT_STATE_ERR4	INTEL_PT_STATE_NO_PSB
  91#else
  92#define INTEL_PT_STATE_ERR1	(decoder->pkt_state)
  93#define INTEL_PT_STATE_ERR2	INTEL_PT_STATE_NO_IP
  94#define INTEL_PT_STATE_ERR3	INTEL_PT_STATE_ERR_RESYNC
  95#define INTEL_PT_STATE_ERR4	INTEL_PT_STATE_IN_SYNC
  96#endif
  97
  98struct intel_pt_decoder {
  99	int (*get_trace)(struct intel_pt_buffer *buffer, void *data);
 100	int (*walk_insn)(struct intel_pt_insn *intel_pt_insn,
 101			 uint64_t *insn_cnt_ptr, uint64_t *ip, uint64_t to_ip,
 102			 uint64_t max_insn_cnt, void *data);
 103	bool (*pgd_ip)(uint64_t ip, void *data);
 
 
 104	void *data;
 105	struct intel_pt_state state;
 106	const unsigned char *buf;
 107	size_t len;
 108	bool return_compression;
 109	bool branch_enable;
 110	bool mtc_insn;
 111	bool pge;
 112	bool have_tma;
 113	bool have_cyc;
 114	bool fixup_last_mtc;
 115	bool have_last_ip;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 116	uint64_t pos;
 117	uint64_t last_ip;
 118	uint64_t ip;
 119	uint64_t cr3;
 120	uint64_t timestamp;
 121	uint64_t tsc_timestamp;
 122	uint64_t ref_timestamp;
 
 123	uint64_t sample_timestamp;
 124	uint64_t ret_addr;
 125	uint64_t ctc_timestamp;
 126	uint64_t ctc_delta;
 127	uint64_t cycle_cnt;
 128	uint64_t cyc_ref_timestamp;
 
 
 
 
 
 129	uint32_t last_mtc;
 130	uint32_t tsc_ctc_ratio_n;
 131	uint32_t tsc_ctc_ratio_d;
 132	uint32_t tsc_ctc_mult;
 133	uint32_t tsc_slip;
 134	uint32_t ctc_rem_mask;
 135	int mtc_shift;
 136	struct intel_pt_stack stack;
 137	enum intel_pt_pkt_state pkt_state;
 
 
 
 
 138	struct intel_pt_pkt packet;
 139	struct intel_pt_pkt tnt;
 140	int pkt_step;
 141	int pkt_len;
 142	int last_packet_type;
 143	unsigned int cbr;
 144	unsigned int cbr_seen;
 145	unsigned int max_non_turbo_ratio;
 146	double max_non_turbo_ratio_fp;
 147	double cbr_cyc_to_tsc;
 148	double calc_cyc_to_tsc;
 149	bool have_calc_cyc_to_tsc;
 150	int exec_mode;
 151	unsigned int insn_bytes;
 152	uint64_t period;
 153	enum intel_pt_period_type period_type;
 154	uint64_t tot_insn_cnt;
 155	uint64_t period_insn_cnt;
 156	uint64_t period_mask;
 157	uint64_t period_ticks;
 158	uint64_t last_masked_timestamp;
 
 
 
 
 
 
 
 159	bool continuous_period;
 160	bool overflow;
 161	bool set_fup_tx_flags;
 162	bool set_fup_ptw;
 163	bool set_fup_mwait;
 164	bool set_fup_pwre;
 165	bool set_fup_exstop;
 
 
 
 
 
 166	unsigned int fup_tx_flags;
 167	unsigned int tx_flags;
 168	uint64_t fup_ptw_payload;
 169	uint64_t fup_mwait_payload;
 170	uint64_t fup_pwre_payload;
 171	uint64_t cbr_payload;
 172	uint64_t timestamp_insn_cnt;
 173	uint64_t sample_insn_cnt;
 174	uint64_t stuck_ip;
 
 
 175	int no_progress;
 176	int stuck_ip_prd;
 177	int stuck_ip_cnt;
 
 178	const unsigned char *next_buf;
 179	size_t next_len;
 180	unsigned char temp_buf[INTEL_PT_PKT_MAX_SZ];
 
 
 181};
 182
 183static uint64_t intel_pt_lower_power_of_2(uint64_t x)
 184{
 185	int i;
 186
 187	for (i = 0; x != 1; i++)
 188		x >>= 1;
 189
 190	return x << i;
 191}
 192
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 193static void intel_pt_setup_period(struct intel_pt_decoder *decoder)
 194{
 195	if (decoder->period_type == INTEL_PT_PERIOD_TICKS) {
 196		uint64_t period;
 197
 198		period = intel_pt_lower_power_of_2(decoder->period);
 199		decoder->period_mask  = ~(period - 1);
 200		decoder->period_ticks = period;
 201	}
 202}
 203
 204static uint64_t multdiv(uint64_t t, uint32_t n, uint32_t d)
 205{
 206	if (!d)
 207		return 0;
 208	return (t / d) * n + ((t % d) * n) / d;
 209}
 210
 211struct intel_pt_decoder *intel_pt_decoder_new(struct intel_pt_params *params)
 212{
 213	struct intel_pt_decoder *decoder;
 214
 215	if (!params->get_trace || !params->walk_insn)
 216		return NULL;
 217
 218	decoder = zalloc(sizeof(struct intel_pt_decoder));
 219	if (!decoder)
 220		return NULL;
 221
 222	decoder->get_trace          = params->get_trace;
 223	decoder->walk_insn          = params->walk_insn;
 224	decoder->pgd_ip             = params->pgd_ip;
 
 
 225	decoder->data               = params->data;
 226	decoder->return_compression = params->return_compression;
 227	decoder->branch_enable      = params->branch_enable;
 
 
 
 
 
 
 
 228
 
 
 
 229	decoder->period             = params->period;
 230	decoder->period_type        = params->period_type;
 231
 232	decoder->max_non_turbo_ratio    = params->max_non_turbo_ratio;
 233	decoder->max_non_turbo_ratio_fp = params->max_non_turbo_ratio;
 234
 
 
 235	intel_pt_setup_period(decoder);
 236
 237	decoder->mtc_shift = params->mtc_period;
 238	decoder->ctc_rem_mask = (1 << decoder->mtc_shift) - 1;
 239
 240	decoder->tsc_ctc_ratio_n = params->tsc_ctc_ratio_n;
 241	decoder->tsc_ctc_ratio_d = params->tsc_ctc_ratio_d;
 242
 243	if (!decoder->tsc_ctc_ratio_n)
 244		decoder->tsc_ctc_ratio_d = 0;
 245
 246	if (decoder->tsc_ctc_ratio_d) {
 247		if (!(decoder->tsc_ctc_ratio_n % decoder->tsc_ctc_ratio_d))
 248			decoder->tsc_ctc_mult = decoder->tsc_ctc_ratio_n /
 249						decoder->tsc_ctc_ratio_d;
 250
 251		/*
 252		 * Allow for timestamps appearing to backwards because a TSC
 253		 * packet has slipped past a MTC packet, so allow 2 MTC ticks
 254		 * or ...
 255		 */
 256		decoder->tsc_slip = multdiv(2 << decoder->mtc_shift,
 257					decoder->tsc_ctc_ratio_n,
 258					decoder->tsc_ctc_ratio_d);
 259	}
 260	/* ... or 0x100 paranoia */
 261	if (decoder->tsc_slip < 0x100)
 262		decoder->tsc_slip = 0x100;
 
 
 
 
 
 263
 264	intel_pt_log("timestamp: mtc_shift %u\n", decoder->mtc_shift);
 265	intel_pt_log("timestamp: tsc_ctc_ratio_n %u\n", decoder->tsc_ctc_ratio_n);
 266	intel_pt_log("timestamp: tsc_ctc_ratio_d %u\n", decoder->tsc_ctc_ratio_d);
 267	intel_pt_log("timestamp: tsc_ctc_mult %u\n", decoder->tsc_ctc_mult);
 268	intel_pt_log("timestamp: tsc_slip %#x\n", decoder->tsc_slip);
 269
 
 
 
 270	return decoder;
 271}
 272
 
 
 
 
 
 
 273static void intel_pt_pop_blk(struct intel_pt_stack *stack)
 274{
 275	struct intel_pt_blk *blk = stack->blk;
 276
 277	stack->blk = blk->prev;
 278	if (!stack->spare)
 279		stack->spare = blk;
 280	else
 281		free(blk);
 282}
 283
 284static uint64_t intel_pt_pop(struct intel_pt_stack *stack)
 285{
 286	if (!stack->pos) {
 287		if (!stack->blk)
 288			return 0;
 289		intel_pt_pop_blk(stack);
 290		if (!stack->blk)
 291			return 0;
 292		stack->pos = INTEL_PT_BLK_SIZE;
 293	}
 294	return stack->blk->ip[--stack->pos];
 295}
 296
 297static int intel_pt_alloc_blk(struct intel_pt_stack *stack)
 298{
 299	struct intel_pt_blk *blk;
 300
 301	if (stack->spare) {
 302		blk = stack->spare;
 303		stack->spare = NULL;
 304	} else {
 305		blk = malloc(sizeof(struct intel_pt_blk));
 306		if (!blk)
 307			return -ENOMEM;
 308	}
 309
 310	blk->prev = stack->blk;
 311	stack->blk = blk;
 312	stack->pos = 0;
 313	return 0;
 314}
 315
 316static int intel_pt_push(struct intel_pt_stack *stack, uint64_t ip)
 317{
 318	int err;
 319
 320	if (!stack->blk || stack->pos == INTEL_PT_BLK_SIZE) {
 321		err = intel_pt_alloc_blk(stack);
 322		if (err)
 323			return err;
 324	}
 325
 326	stack->blk->ip[stack->pos++] = ip;
 327	return 0;
 328}
 329
 330static void intel_pt_clear_stack(struct intel_pt_stack *stack)
 331{
 332	while (stack->blk)
 333		intel_pt_pop_blk(stack);
 334	stack->pos = 0;
 335}
 336
 337static void intel_pt_free_stack(struct intel_pt_stack *stack)
 338{
 339	intel_pt_clear_stack(stack);
 340	zfree(&stack->blk);
 341	zfree(&stack->spare);
 342}
 343
 344void intel_pt_decoder_free(struct intel_pt_decoder *decoder)
 345{
 346	intel_pt_free_stack(&decoder->stack);
 347	free(decoder);
 348}
 349
 350static int intel_pt_ext_err(int code)
 351{
 352	switch (code) {
 353	case -ENOMEM:
 354		return INTEL_PT_ERR_NOMEM;
 355	case -ENOSYS:
 356		return INTEL_PT_ERR_INTERN;
 357	case -EBADMSG:
 358		return INTEL_PT_ERR_BADPKT;
 359	case -ENODATA:
 360		return INTEL_PT_ERR_NODATA;
 361	case -EILSEQ:
 362		return INTEL_PT_ERR_NOINSN;
 363	case -ENOENT:
 364		return INTEL_PT_ERR_MISMAT;
 365	case -EOVERFLOW:
 366		return INTEL_PT_ERR_OVR;
 367	case -ENOSPC:
 368		return INTEL_PT_ERR_LOST;
 369	case -ELOOP:
 370		return INTEL_PT_ERR_NELOOP;
 
 
 371	default:
 372		return INTEL_PT_ERR_UNK;
 373	}
 374}
 375
 376static const char *intel_pt_err_msgs[] = {
 377	[INTEL_PT_ERR_NOMEM]  = "Memory allocation failed",
 378	[INTEL_PT_ERR_INTERN] = "Internal error",
 379	[INTEL_PT_ERR_BADPKT] = "Bad packet",
 380	[INTEL_PT_ERR_NODATA] = "No more data",
 381	[INTEL_PT_ERR_NOINSN] = "Failed to get instruction",
 382	[INTEL_PT_ERR_MISMAT] = "Trace doesn't match instruction",
 383	[INTEL_PT_ERR_OVR]    = "Overflow packet",
 384	[INTEL_PT_ERR_LOST]   = "Lost trace data",
 385	[INTEL_PT_ERR_UNK]    = "Unknown error!",
 386	[INTEL_PT_ERR_NELOOP] = "Never-ending loop",
 
 387};
 388
 389int intel_pt__strerror(int code, char *buf, size_t buflen)
 390{
 391	if (code < 1 || code >= INTEL_PT_ERR_MAX)
 392		code = INTEL_PT_ERR_UNK;
 393	strlcpy(buf, intel_pt_err_msgs[code], buflen);
 394	return 0;
 395}
 396
 397static uint64_t intel_pt_calc_ip(const struct intel_pt_pkt *packet,
 398				 uint64_t last_ip)
 399{
 400	uint64_t ip;
 401
 402	switch (packet->count) {
 403	case 1:
 404		ip = (last_ip & (uint64_t)0xffffffffffff0000ULL) |
 405		     packet->payload;
 406		break;
 407	case 2:
 408		ip = (last_ip & (uint64_t)0xffffffff00000000ULL) |
 409		     packet->payload;
 410		break;
 411	case 3:
 412		ip = packet->payload;
 413		/* Sign-extend 6-byte ip */
 414		if (ip & (uint64_t)0x800000000000ULL)
 415			ip |= (uint64_t)0xffff000000000000ULL;
 416		break;
 417	case 4:
 418		ip = (last_ip & (uint64_t)0xffff000000000000ULL) |
 419		     packet->payload;
 420		break;
 421	case 6:
 422		ip = packet->payload;
 423		break;
 424	default:
 425		return 0;
 426	}
 427
 428	return ip;
 429}
 430
 431static inline void intel_pt_set_last_ip(struct intel_pt_decoder *decoder)
 432{
 433	decoder->last_ip = intel_pt_calc_ip(&decoder->packet, decoder->last_ip);
 434	decoder->have_last_ip = true;
 435}
 436
 437static inline void intel_pt_set_ip(struct intel_pt_decoder *decoder)
 438{
 439	intel_pt_set_last_ip(decoder);
 440	decoder->ip = decoder->last_ip;
 441}
 442
 443static void intel_pt_decoder_log_packet(struct intel_pt_decoder *decoder)
 444{
 445	intel_pt_log_packet(&decoder->packet, decoder->pkt_len, decoder->pos,
 446			    decoder->buf);
 447}
 448
 449static int intel_pt_bug(struct intel_pt_decoder *decoder)
 450{
 451	intel_pt_log("ERROR: Internal error\n");
 452	decoder->pkt_state = INTEL_PT_STATE_NO_PSB;
 453	return -ENOSYS;
 454}
 455
 456static inline void intel_pt_clear_tx_flags(struct intel_pt_decoder *decoder)
 457{
 458	decoder->tx_flags = 0;
 459}
 460
 461static inline void intel_pt_update_in_tx(struct intel_pt_decoder *decoder)
 462{
 463	decoder->tx_flags = decoder->packet.payload & INTEL_PT_IN_TX;
 464}
 465
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 466static int intel_pt_bad_packet(struct intel_pt_decoder *decoder)
 467{
 468	intel_pt_clear_tx_flags(decoder);
 469	decoder->have_tma = false;
 470	decoder->pkt_len = 1;
 471	decoder->pkt_step = 1;
 472	intel_pt_decoder_log_packet(decoder);
 473	if (decoder->pkt_state != INTEL_PT_STATE_NO_PSB) {
 474		intel_pt_log("ERROR: Bad packet\n");
 475		decoder->pkt_state = INTEL_PT_STATE_ERR1;
 476	}
 477	return -EBADMSG;
 478}
 479
 480static int intel_pt_get_data(struct intel_pt_decoder *decoder)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 481{
 482	struct intel_pt_buffer buffer = { .buf = 0, };
 483	int ret;
 484
 485	decoder->pkt_step = 0;
 486
 487	intel_pt_log("Getting more data\n");
 488	ret = decoder->get_trace(&buffer, decoder->data);
 489	if (ret)
 490		return ret;
 491	decoder->buf = buffer.buf;
 492	decoder->len = buffer.len;
 493	if (!decoder->len) {
 494		intel_pt_log("No more data\n");
 495		return -ENODATA;
 496	}
 497	if (!buffer.consecutive) {
 498		decoder->ip = 0;
 499		decoder->pkt_state = INTEL_PT_STATE_NO_PSB;
 500		decoder->ref_timestamp = buffer.ref_timestamp;
 501		decoder->timestamp = 0;
 502		decoder->have_tma = false;
 503		decoder->state.trace_nr = buffer.trace_nr;
 
 504		intel_pt_log("Reference timestamp 0x%" PRIx64 "\n",
 505			     decoder->ref_timestamp);
 506		return -ENOLINK;
 507	}
 508
 509	return 0;
 510}
 511
 512static int intel_pt_get_next_data(struct intel_pt_decoder *decoder)
 
 513{
 514	if (!decoder->next_buf)
 515		return intel_pt_get_data(decoder);
 516
 517	decoder->buf = decoder->next_buf;
 518	decoder->len = decoder->next_len;
 519	decoder->next_buf = 0;
 520	decoder->next_len = 0;
 521	return 0;
 522}
 523
 524static int intel_pt_get_split_packet(struct intel_pt_decoder *decoder)
 525{
 526	unsigned char *buf = decoder->temp_buf;
 527	size_t old_len, len, n;
 528	int ret;
 529
 530	old_len = decoder->len;
 531	len = decoder->len;
 532	memcpy(buf, decoder->buf, len);
 533
 534	ret = intel_pt_get_data(decoder);
 535	if (ret) {
 536		decoder->pos += old_len;
 537		return ret < 0 ? ret : -EINVAL;
 538	}
 539
 540	n = INTEL_PT_PKT_MAX_SZ - len;
 541	if (n > decoder->len)
 542		n = decoder->len;
 543	memcpy(buf + len, decoder->buf, n);
 544	len += n;
 545
 546	ret = intel_pt_get_packet(buf, len, &decoder->packet);
 
 547	if (ret < (int)old_len) {
 548		decoder->next_buf = decoder->buf;
 549		decoder->next_len = decoder->len;
 550		decoder->buf = buf;
 551		decoder->len = old_len;
 552		return intel_pt_bad_packet(decoder);
 553	}
 554
 555	decoder->next_buf = decoder->buf + (ret - old_len);
 556	decoder->next_len = decoder->len - (ret - old_len);
 557
 558	decoder->buf = buf;
 559	decoder->len = ret;
 560
 561	return ret;
 562}
 563
 564struct intel_pt_pkt_info {
 565	struct intel_pt_decoder	  *decoder;
 566	struct intel_pt_pkt       packet;
 567	uint64_t                  pos;
 568	int                       pkt_len;
 569	int                       last_packet_type;
 570	void                      *data;
 571};
 572
 573typedef int (*intel_pt_pkt_cb_t)(struct intel_pt_pkt_info *pkt_info);
 574
 575/* Lookahead packets in current buffer */
 576static int intel_pt_pkt_lookahead(struct intel_pt_decoder *decoder,
 577				  intel_pt_pkt_cb_t cb, void *data)
 578{
 579	struct intel_pt_pkt_info pkt_info;
 580	const unsigned char *buf = decoder->buf;
 
 581	size_t len = decoder->len;
 582	int ret;
 583
 584	pkt_info.decoder          = decoder;
 585	pkt_info.pos              = decoder->pos;
 586	pkt_info.pkt_len          = decoder->pkt_step;
 587	pkt_info.last_packet_type = decoder->last_packet_type;
 588	pkt_info.data             = data;
 589
 590	while (1) {
 591		do {
 592			pkt_info.pos += pkt_info.pkt_len;
 593			buf          += pkt_info.pkt_len;
 594			len          -= pkt_info.pkt_len;
 595
 596			if (!len)
 597				return INTEL_PT_NEED_MORE_BYTES;
 598
 599			ret = intel_pt_get_packet(buf, len, &pkt_info.packet);
 
 600			if (!ret)
 601				return INTEL_PT_NEED_MORE_BYTES;
 602			if (ret < 0)
 603				return ret;
 604
 605			pkt_info.pkt_len = ret;
 606		} while (pkt_info.packet.type == INTEL_PT_PAD);
 607
 608		ret = cb(&pkt_info);
 609		if (ret)
 610			return 0;
 611
 612		pkt_info.last_packet_type = pkt_info.packet.type;
 613	}
 614}
 615
 616struct intel_pt_calc_cyc_to_tsc_info {
 617	uint64_t        cycle_cnt;
 618	unsigned int    cbr;
 619	uint32_t        last_mtc;
 620	uint64_t        ctc_timestamp;
 621	uint64_t        ctc_delta;
 622	uint64_t        tsc_timestamp;
 623	uint64_t        timestamp;
 624	bool            have_tma;
 625	bool            fixup_last_mtc;
 626	bool            from_mtc;
 627	double          cbr_cyc_to_tsc;
 628};
 629
 630/*
 631 * MTC provides a 8-bit slice of CTC but the TMA packet only provides the lower
 632 * 16 bits of CTC. If mtc_shift > 8 then some of the MTC bits are not in the CTC
 633 * provided by the TMA packet. Fix-up the last_mtc calculated from the TMA
 634 * packet by copying the missing bits from the current MTC assuming the least
 635 * difference between the two, and that the current MTC comes after last_mtc.
 636 */
 637static void intel_pt_fixup_last_mtc(uint32_t mtc, int mtc_shift,
 638				    uint32_t *last_mtc)
 639{
 640	uint32_t first_missing_bit = 1U << (16 - mtc_shift);
 641	uint32_t mask = ~(first_missing_bit - 1);
 642
 643	*last_mtc |= mtc & mask;
 644	if (*last_mtc >= mtc) {
 645		*last_mtc -= first_missing_bit;
 646		*last_mtc &= 0xff;
 647	}
 648}
 649
 650static int intel_pt_calc_cyc_cb(struct intel_pt_pkt_info *pkt_info)
 651{
 652	struct intel_pt_decoder *decoder = pkt_info->decoder;
 653	struct intel_pt_calc_cyc_to_tsc_info *data = pkt_info->data;
 654	uint64_t timestamp;
 655	double cyc_to_tsc;
 656	unsigned int cbr;
 657	uint32_t mtc, mtc_delta, ctc, fc, ctc_rem;
 658
 659	switch (pkt_info->packet.type) {
 660	case INTEL_PT_TNT:
 661	case INTEL_PT_TIP_PGE:
 662	case INTEL_PT_TIP:
 663	case INTEL_PT_FUP:
 664	case INTEL_PT_PSB:
 665	case INTEL_PT_PIP:
 666	case INTEL_PT_MODE_EXEC:
 667	case INTEL_PT_MODE_TSX:
 668	case INTEL_PT_PSBEND:
 669	case INTEL_PT_PAD:
 670	case INTEL_PT_VMCS:
 671	case INTEL_PT_MNT:
 672	case INTEL_PT_PTWRITE:
 673	case INTEL_PT_PTWRITE_IP:
 
 
 
 
 
 
 
 674		return 0;
 675
 676	case INTEL_PT_MTC:
 677		if (!data->have_tma)
 678			return 0;
 679
 680		mtc = pkt_info->packet.payload;
 681		if (decoder->mtc_shift > 8 && data->fixup_last_mtc) {
 682			data->fixup_last_mtc = false;
 683			intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
 684						&data->last_mtc);
 685		}
 686		if (mtc > data->last_mtc)
 687			mtc_delta = mtc - data->last_mtc;
 688		else
 689			mtc_delta = mtc + 256 - data->last_mtc;
 690		data->ctc_delta += mtc_delta << decoder->mtc_shift;
 691		data->last_mtc = mtc;
 692
 693		if (decoder->tsc_ctc_mult) {
 694			timestamp = data->ctc_timestamp +
 695				data->ctc_delta * decoder->tsc_ctc_mult;
 696		} else {
 697			timestamp = data->ctc_timestamp +
 698				multdiv(data->ctc_delta,
 699					decoder->tsc_ctc_ratio_n,
 700					decoder->tsc_ctc_ratio_d);
 701		}
 702
 703		if (timestamp < data->timestamp)
 704			return 1;
 705
 706		if (pkt_info->last_packet_type != INTEL_PT_CYC) {
 707			data->timestamp = timestamp;
 708			return 0;
 709		}
 710
 711		break;
 712
 713	case INTEL_PT_TSC:
 714		/*
 715		 * For now, do not support using TSC packets - refer
 716		 * intel_pt_calc_cyc_to_tsc().
 717		 */
 718		if (data->from_mtc)
 719			return 1;
 720		timestamp = pkt_info->packet.payload |
 721			    (data->timestamp & (0xffULL << 56));
 722		if (data->from_mtc && timestamp < data->timestamp &&
 723		    data->timestamp - timestamp < decoder->tsc_slip)
 724			return 1;
 725		if (timestamp < data->timestamp)
 726			timestamp += (1ULL << 56);
 727		if (pkt_info->last_packet_type != INTEL_PT_CYC) {
 728			if (data->from_mtc)
 729				return 1;
 730			data->tsc_timestamp = timestamp;
 731			data->timestamp = timestamp;
 732			return 0;
 733		}
 734		break;
 735
 736	case INTEL_PT_TMA:
 737		if (data->from_mtc)
 738			return 1;
 739
 740		if (!decoder->tsc_ctc_ratio_d)
 741			return 0;
 742
 743		ctc = pkt_info->packet.payload;
 744		fc = pkt_info->packet.count;
 745		ctc_rem = ctc & decoder->ctc_rem_mask;
 746
 747		data->last_mtc = (ctc >> decoder->mtc_shift) & 0xff;
 748
 749		data->ctc_timestamp = data->tsc_timestamp - fc;
 750		if (decoder->tsc_ctc_mult) {
 751			data->ctc_timestamp -= ctc_rem * decoder->tsc_ctc_mult;
 752		} else {
 753			data->ctc_timestamp -=
 754				multdiv(ctc_rem, decoder->tsc_ctc_ratio_n,
 755					decoder->tsc_ctc_ratio_d);
 756		}
 757
 758		data->ctc_delta = 0;
 759		data->have_tma = true;
 760		data->fixup_last_mtc = true;
 761
 762		return 0;
 763
 764	case INTEL_PT_CYC:
 765		data->cycle_cnt += pkt_info->packet.payload;
 766		return 0;
 767
 768	case INTEL_PT_CBR:
 769		cbr = pkt_info->packet.payload;
 770		if (data->cbr && data->cbr != cbr)
 771			return 1;
 772		data->cbr = cbr;
 773		data->cbr_cyc_to_tsc = decoder->max_non_turbo_ratio_fp / cbr;
 774		return 0;
 775
 776	case INTEL_PT_TIP_PGD:
 777	case INTEL_PT_TRACESTOP:
 778	case INTEL_PT_EXSTOP:
 779	case INTEL_PT_EXSTOP_IP:
 780	case INTEL_PT_MWAIT:
 781	case INTEL_PT_PWRE:
 782	case INTEL_PT_PWRX:
 783	case INTEL_PT_OVF:
 784	case INTEL_PT_BAD: /* Does not happen */
 785	default:
 786		return 1;
 787	}
 788
 789	if (!data->cbr && decoder->cbr) {
 790		data->cbr = decoder->cbr;
 791		data->cbr_cyc_to_tsc = decoder->cbr_cyc_to_tsc;
 792	}
 793
 794	if (!data->cycle_cnt)
 795		return 1;
 796
 797	cyc_to_tsc = (double)(timestamp - decoder->timestamp) / data->cycle_cnt;
 798
 799	if (data->cbr && cyc_to_tsc > data->cbr_cyc_to_tsc &&
 800	    cyc_to_tsc / data->cbr_cyc_to_tsc > 1.25) {
 801		intel_pt_log("Timestamp: calculated %g TSC ticks per cycle too big (c.f. CBR-based value %g), pos " x64_fmt "\n",
 802			     cyc_to_tsc, data->cbr_cyc_to_tsc, pkt_info->pos);
 803		return 1;
 804	}
 805
 806	decoder->calc_cyc_to_tsc = cyc_to_tsc;
 807	decoder->have_calc_cyc_to_tsc = true;
 808
 809	if (data->cbr) {
 810		intel_pt_log("Timestamp: calculated %g TSC ticks per cycle c.f. CBR-based value %g, pos " x64_fmt "\n",
 811			     cyc_to_tsc, data->cbr_cyc_to_tsc, pkt_info->pos);
 812	} else {
 813		intel_pt_log("Timestamp: calculated %g TSC ticks per cycle c.f. unknown CBR-based value, pos " x64_fmt "\n",
 814			     cyc_to_tsc, pkt_info->pos);
 815	}
 816
 817	return 1;
 818}
 819
 820static void intel_pt_calc_cyc_to_tsc(struct intel_pt_decoder *decoder,
 821				     bool from_mtc)
 822{
 823	struct intel_pt_calc_cyc_to_tsc_info data = {
 824		.cycle_cnt      = 0,
 825		.cbr            = 0,
 826		.last_mtc       = decoder->last_mtc,
 827		.ctc_timestamp  = decoder->ctc_timestamp,
 828		.ctc_delta      = decoder->ctc_delta,
 829		.tsc_timestamp  = decoder->tsc_timestamp,
 830		.timestamp      = decoder->timestamp,
 831		.have_tma       = decoder->have_tma,
 832		.fixup_last_mtc = decoder->fixup_last_mtc,
 833		.from_mtc       = from_mtc,
 834		.cbr_cyc_to_tsc = 0,
 835	};
 836
 837	/*
 838	 * For now, do not support using TSC packets for at least the reasons:
 839	 * 1) timing might have stopped
 840	 * 2) TSC packets within PSB+ can slip against CYC packets
 841	 */
 842	if (!from_mtc)
 843		return;
 844
 845	intel_pt_pkt_lookahead(decoder, intel_pt_calc_cyc_cb, &data);
 846}
 847
 848static int intel_pt_get_next_packet(struct intel_pt_decoder *decoder)
 849{
 850	int ret;
 851
 852	decoder->last_packet_type = decoder->packet.type;
 853
 854	do {
 855		decoder->pos += decoder->pkt_step;
 856		decoder->buf += decoder->pkt_step;
 857		decoder->len -= decoder->pkt_step;
 858
 859		if (!decoder->len) {
 860			ret = intel_pt_get_next_data(decoder);
 861			if (ret)
 862				return ret;
 863		}
 864
 
 865		ret = intel_pt_get_packet(decoder->buf, decoder->len,
 866					  &decoder->packet);
 867		if (ret == INTEL_PT_NEED_MORE_BYTES &&
 868		    decoder->len < INTEL_PT_PKT_MAX_SZ && !decoder->next_buf) {
 869			ret = intel_pt_get_split_packet(decoder);
 870			if (ret < 0)
 871				return ret;
 872		}
 873		if (ret <= 0)
 874			return intel_pt_bad_packet(decoder);
 875
 876		decoder->pkt_len = ret;
 877		decoder->pkt_step = ret;
 878		intel_pt_decoder_log_packet(decoder);
 879	} while (decoder->packet.type == INTEL_PT_PAD);
 880
 881	return 0;
 882}
 883
 884static uint64_t intel_pt_next_period(struct intel_pt_decoder *decoder)
 885{
 886	uint64_t timestamp, masked_timestamp;
 887
 888	timestamp = decoder->timestamp + decoder->timestamp_insn_cnt;
 889	masked_timestamp = timestamp & decoder->period_mask;
 890	if (decoder->continuous_period) {
 891		if (masked_timestamp != decoder->last_masked_timestamp)
 892			return 1;
 893	} else {
 894		timestamp += 1;
 895		masked_timestamp = timestamp & decoder->period_mask;
 896		if (masked_timestamp != decoder->last_masked_timestamp) {
 897			decoder->last_masked_timestamp = masked_timestamp;
 898			decoder->continuous_period = true;
 899		}
 900	}
 
 
 
 
 901	return decoder->period_ticks - (timestamp - masked_timestamp);
 902}
 903
 904static uint64_t intel_pt_next_sample(struct intel_pt_decoder *decoder)
 905{
 906	switch (decoder->period_type) {
 907	case INTEL_PT_PERIOD_INSTRUCTIONS:
 908		return decoder->period - decoder->period_insn_cnt;
 909	case INTEL_PT_PERIOD_TICKS:
 910		return intel_pt_next_period(decoder);
 911	case INTEL_PT_PERIOD_NONE:
 912	case INTEL_PT_PERIOD_MTC:
 913	default:
 914		return 0;
 915	}
 916}
 917
 918static void intel_pt_sample_insn(struct intel_pt_decoder *decoder)
 919{
 920	uint64_t timestamp, masked_timestamp;
 921
 922	switch (decoder->period_type) {
 923	case INTEL_PT_PERIOD_INSTRUCTIONS:
 924		decoder->period_insn_cnt = 0;
 925		break;
 926	case INTEL_PT_PERIOD_TICKS:
 927		timestamp = decoder->timestamp + decoder->timestamp_insn_cnt;
 928		masked_timestamp = timestamp & decoder->period_mask;
 929		decoder->last_masked_timestamp = masked_timestamp;
 
 
 
 930		break;
 931	case INTEL_PT_PERIOD_NONE:
 932	case INTEL_PT_PERIOD_MTC:
 933	default:
 934		break;
 935	}
 936
 937	decoder->state.type |= INTEL_PT_INSTRUCTION;
 938}
 939
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 940static int intel_pt_walk_insn(struct intel_pt_decoder *decoder,
 941			      struct intel_pt_insn *intel_pt_insn, uint64_t ip)
 942{
 943	uint64_t max_insn_cnt, insn_cnt = 0;
 944	int err;
 945
 946	if (!decoder->mtc_insn)
 947		decoder->mtc_insn = true;
 948
 949	max_insn_cnt = intel_pt_next_sample(decoder);
 950
 951	err = decoder->walk_insn(intel_pt_insn, &insn_cnt, &decoder->ip, ip,
 952				 max_insn_cnt, decoder->data);
 953
 954	decoder->tot_insn_cnt += insn_cnt;
 955	decoder->timestamp_insn_cnt += insn_cnt;
 956	decoder->sample_insn_cnt += insn_cnt;
 957	decoder->period_insn_cnt += insn_cnt;
 958
 959	if (err) {
 960		decoder->no_progress = 0;
 961		decoder->pkt_state = INTEL_PT_STATE_ERR2;
 962		intel_pt_log_at("ERROR: Failed to get instruction",
 963				decoder->ip);
 964		if (err == -ENOENT)
 965			return -ENOLINK;
 966		return -EILSEQ;
 967	}
 968
 969	if (ip && decoder->ip == ip) {
 970		err = -EAGAIN;
 971		goto out;
 972	}
 973
 974	if (max_insn_cnt && insn_cnt >= max_insn_cnt)
 975		intel_pt_sample_insn(decoder);
 976
 977	if (intel_pt_insn->branch == INTEL_PT_BR_NO_BRANCH) {
 978		decoder->state.type = INTEL_PT_INSTRUCTION;
 979		decoder->state.from_ip = decoder->ip;
 980		decoder->state.to_ip = 0;
 981		decoder->ip += intel_pt_insn->length;
 982		err = INTEL_PT_RETURN;
 983		goto out;
 984	}
 985
 986	if (intel_pt_insn->op == INTEL_PT_OP_CALL) {
 987		/* Zero-length calls are excluded */
 988		if (intel_pt_insn->branch != INTEL_PT_BR_UNCONDITIONAL ||
 989		    intel_pt_insn->rel) {
 990			err = intel_pt_push(&decoder->stack, decoder->ip +
 991					    intel_pt_insn->length);
 992			if (err)
 993				goto out;
 994		}
 995	} else if (intel_pt_insn->op == INTEL_PT_OP_RET) {
 996		decoder->ret_addr = intel_pt_pop(&decoder->stack);
 997	}
 998
 999	if (intel_pt_insn->branch == INTEL_PT_BR_UNCONDITIONAL) {
1000		int cnt = decoder->no_progress++;
1001
1002		decoder->state.from_ip = decoder->ip;
1003		decoder->ip += intel_pt_insn->length +
1004				intel_pt_insn->rel;
1005		decoder->state.to_ip = decoder->ip;
1006		err = INTEL_PT_RETURN;
1007
1008		/*
1009		 * Check for being stuck in a loop.  This can happen if a
1010		 * decoder error results in the decoder erroneously setting the
1011		 * ip to an address that is itself in an infinite loop that
1012		 * consumes no packets.  When that happens, there must be an
1013		 * unconditional branch.
1014		 */
1015		if (cnt) {
1016			if (cnt == 1) {
1017				decoder->stuck_ip = decoder->state.to_ip;
1018				decoder->stuck_ip_prd = 1;
1019				decoder->stuck_ip_cnt = 1;
1020			} else if (cnt > INTEL_PT_MAX_LOOPS ||
1021				   decoder->state.to_ip == decoder->stuck_ip) {
1022				intel_pt_log_at("ERROR: Never-ending loop",
1023						decoder->state.to_ip);
1024				decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1025				err = -ELOOP;
1026				goto out;
1027			} else if (!--decoder->stuck_ip_cnt) {
1028				decoder->stuck_ip_prd += 1;
1029				decoder->stuck_ip_cnt = decoder->stuck_ip_prd;
1030				decoder->stuck_ip = decoder->state.to_ip;
1031			}
1032		}
1033		goto out_no_progress;
1034	}
1035out:
1036	decoder->no_progress = 0;
1037out_no_progress:
1038	decoder->state.insn_op = intel_pt_insn->op;
1039	decoder->state.insn_len = intel_pt_insn->length;
1040	memcpy(decoder->state.insn, intel_pt_insn->buf,
1041	       INTEL_PT_INSN_BUF_SZ);
1042
1043	if (decoder->tx_flags & INTEL_PT_IN_TX)
1044		decoder->state.flags |= INTEL_PT_IN_TX;
1045
1046	return err;
1047}
1048
1049static bool intel_pt_fup_event(struct intel_pt_decoder *decoder)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1050{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1051	bool ret = false;
1052
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1053	if (decoder->set_fup_tx_flags) {
1054		decoder->set_fup_tx_flags = false;
1055		decoder->tx_flags = decoder->fup_tx_flags;
1056		decoder->state.type = INTEL_PT_TRANSACTION;
1057		decoder->state.from_ip = decoder->ip;
1058		decoder->state.to_ip = 0;
1059		decoder->state.flags = decoder->fup_tx_flags;
1060		return true;
1061	}
1062	if (decoder->set_fup_ptw) {
1063		decoder->set_fup_ptw = false;
1064		decoder->state.type = INTEL_PT_PTW;
1065		decoder->state.flags |= INTEL_PT_FUP_IP;
1066		decoder->state.from_ip = decoder->ip;
1067		decoder->state.to_ip = 0;
1068		decoder->state.ptw_payload = decoder->fup_ptw_payload;
1069		return true;
1070	}
1071	if (decoder->set_fup_mwait) {
1072		decoder->set_fup_mwait = false;
1073		decoder->state.type = INTEL_PT_MWAIT_OP;
1074		decoder->state.from_ip = decoder->ip;
1075		decoder->state.to_ip = 0;
1076		decoder->state.mwait_payload = decoder->fup_mwait_payload;
1077		ret = true;
1078	}
1079	if (decoder->set_fup_pwre) {
1080		decoder->set_fup_pwre = false;
1081		decoder->state.type |= INTEL_PT_PWR_ENTRY;
1082		decoder->state.type &= ~INTEL_PT_BRANCH;
1083		decoder->state.from_ip = decoder->ip;
1084		decoder->state.to_ip = 0;
1085		decoder->state.pwre_payload = decoder->fup_pwre_payload;
1086		ret = true;
1087	}
1088	if (decoder->set_fup_exstop) {
1089		decoder->set_fup_exstop = false;
1090		decoder->state.type |= INTEL_PT_EX_STOP;
1091		decoder->state.type &= ~INTEL_PT_BRANCH;
1092		decoder->state.flags |= INTEL_PT_FUP_IP;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1093		decoder->state.from_ip = decoder->ip;
1094		decoder->state.to_ip = 0;
1095		ret = true;
 
 
 
1096	}
1097	return ret;
1098}
1099
 
 
 
 
 
 
 
 
 
1100static int intel_pt_walk_fup(struct intel_pt_decoder *decoder)
1101{
1102	struct intel_pt_insn intel_pt_insn;
1103	uint64_t ip;
1104	int err;
1105
1106	ip = decoder->last_ip;
1107
1108	while (1) {
1109		err = intel_pt_walk_insn(decoder, &intel_pt_insn, ip);
1110		if (err == INTEL_PT_RETURN)
1111			return 0;
1112		if (err == -EAGAIN) {
1113			if (intel_pt_fup_event(decoder))
 
 
 
 
1114				return 0;
1115			return err;
1116		}
1117		decoder->set_fup_tx_flags = false;
1118		if (err)
1119			return err;
1120
1121		if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1122			intel_pt_log_at("ERROR: Unexpected indirect branch",
1123					decoder->ip);
1124			decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1125			return -ENOENT;
1126		}
1127
1128		if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1129			intel_pt_log_at("ERROR: Unexpected conditional branch",
1130					decoder->ip);
1131			decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1132			return -ENOENT;
1133		}
1134
1135		intel_pt_bug(decoder);
1136	}
1137}
1138
1139static int intel_pt_walk_tip(struct intel_pt_decoder *decoder)
1140{
1141	struct intel_pt_insn intel_pt_insn;
1142	int err;
1143
1144	err = intel_pt_walk_insn(decoder, &intel_pt_insn, 0);
1145	if (err == INTEL_PT_RETURN &&
1146	    decoder->pgd_ip &&
1147	    decoder->pkt_state == INTEL_PT_STATE_TIP_PGD &&
1148	    (decoder->state.type & INTEL_PT_BRANCH) &&
1149	    decoder->pgd_ip(decoder->state.to_ip, decoder->data)) {
1150		/* Unconditional branch leaving filter region */
1151		decoder->no_progress = 0;
1152		decoder->pge = false;
1153		decoder->continuous_period = false;
1154		decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1155		decoder->state.to_ip = 0;
 
1156		return 0;
1157	}
1158	if (err == INTEL_PT_RETURN)
1159		return 0;
1160	if (err)
1161		return err;
1162
 
 
 
1163	if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1164		if (decoder->pkt_state == INTEL_PT_STATE_TIP_PGD) {
1165			decoder->pge = false;
1166			decoder->continuous_period = false;
1167			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1168			decoder->state.from_ip = decoder->ip;
1169			decoder->state.to_ip = 0;
1170			if (decoder->packet.count != 0)
 
 
1171				decoder->ip = decoder->last_ip;
 
 
1172		} else {
1173			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1174			decoder->state.from_ip = decoder->ip;
1175			if (decoder->packet.count == 0) {
1176				decoder->state.to_ip = 0;
1177			} else {
1178				decoder->state.to_ip = decoder->last_ip;
1179				decoder->ip = decoder->last_ip;
1180			}
1181		}
1182		return 0;
1183	}
1184
1185	if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1186		uint64_t to_ip = decoder->ip + intel_pt_insn.length +
1187				 intel_pt_insn.rel;
1188
1189		if (decoder->pgd_ip &&
1190		    decoder->pkt_state == INTEL_PT_STATE_TIP_PGD &&
1191		    decoder->pgd_ip(to_ip, decoder->data)) {
1192			/* Conditional branch leaving filter region */
1193			decoder->pge = false;
1194			decoder->continuous_period = false;
1195			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1196			decoder->ip = to_ip;
1197			decoder->state.from_ip = decoder->ip;
1198			decoder->state.to_ip = 0;
 
1199			return 0;
1200		}
1201		intel_pt_log_at("ERROR: Conditional branch when expecting indirect branch",
1202				decoder->ip);
1203		decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1204		return -ENOENT;
1205	}
1206
1207	return intel_pt_bug(decoder);
1208}
1209
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1210static int intel_pt_walk_tnt(struct intel_pt_decoder *decoder)
1211{
1212	struct intel_pt_insn intel_pt_insn;
1213	int err;
1214
1215	while (1) {
 
 
1216		err = intel_pt_walk_insn(decoder, &intel_pt_insn, 0);
1217		if (err == INTEL_PT_RETURN)
 
1218			return 0;
1219		if (err)
 
 
1220			return err;
 
1221
1222		if (intel_pt_insn.op == INTEL_PT_OP_RET) {
1223			if (!decoder->return_compression) {
1224				intel_pt_log_at("ERROR: RET when expecting conditional branch",
1225						decoder->ip);
1226				decoder->pkt_state = INTEL_PT_STATE_ERR3;
1227				return -ENOENT;
1228			}
1229			if (!decoder->ret_addr) {
1230				intel_pt_log_at("ERROR: Bad RET compression (stack empty)",
1231						decoder->ip);
1232				decoder->pkt_state = INTEL_PT_STATE_ERR3;
1233				return -ENOENT;
1234			}
1235			if (!(decoder->tnt.payload & BIT63)) {
1236				intel_pt_log_at("ERROR: Bad RET compression (TNT=N)",
1237						decoder->ip);
1238				decoder->pkt_state = INTEL_PT_STATE_ERR3;
1239				return -ENOENT;
1240			}
1241			decoder->tnt.count -= 1;
1242			if (!decoder->tnt.count)
 
 
1243				decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1244			decoder->tnt.payload <<= 1;
1245			decoder->state.from_ip = decoder->ip;
1246			decoder->ip = decoder->ret_addr;
1247			decoder->state.to_ip = decoder->ip;
1248			return 0;
1249		}
1250
1251		if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1252			/* Handle deferred TIPs */
1253			err = intel_pt_get_next_packet(decoder);
1254			if (err)
1255				return err;
1256			if (decoder->packet.type != INTEL_PT_TIP ||
1257			    decoder->packet.count == 0) {
1258				intel_pt_log_at("ERROR: Missing deferred TIP for indirect branch",
1259						decoder->ip);
1260				decoder->pkt_state = INTEL_PT_STATE_ERR3;
1261				decoder->pkt_step = 0;
1262				return -ENOENT;
1263			}
1264			intel_pt_set_last_ip(decoder);
1265			decoder->state.from_ip = decoder->ip;
1266			decoder->state.to_ip = decoder->last_ip;
1267			decoder->ip = decoder->last_ip;
 
 
1268			return 0;
1269		}
1270
1271		if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1272			decoder->tnt.count -= 1;
1273			if (!decoder->tnt.count)
 
 
1274				decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1275			if (decoder->tnt.payload & BIT63) {
1276				decoder->tnt.payload <<= 1;
1277				decoder->state.from_ip = decoder->ip;
1278				decoder->ip += intel_pt_insn.length +
1279					       intel_pt_insn.rel;
1280				decoder->state.to_ip = decoder->ip;
1281				return 0;
1282			}
1283			/* Instruction sample for a non-taken branch */
1284			if (decoder->state.type & INTEL_PT_INSTRUCTION) {
1285				decoder->tnt.payload <<= 1;
1286				decoder->state.type = INTEL_PT_INSTRUCTION;
1287				decoder->state.from_ip = decoder->ip;
1288				decoder->state.to_ip = 0;
1289				decoder->ip += intel_pt_insn.length;
1290				return 0;
1291			}
 
1292			decoder->ip += intel_pt_insn.length;
1293			if (!decoder->tnt.count)
 
1294				return -EAGAIN;
 
1295			decoder->tnt.payload <<= 1;
1296			continue;
1297		}
1298
1299		return intel_pt_bug(decoder);
1300	}
1301}
1302
1303static int intel_pt_mode_tsx(struct intel_pt_decoder *decoder, bool *no_tip)
1304{
1305	unsigned int fup_tx_flags;
1306	int err;
1307
1308	fup_tx_flags = decoder->packet.payload &
1309		       (INTEL_PT_IN_TX | INTEL_PT_ABORT_TX);
1310	err = intel_pt_get_next_packet(decoder);
1311	if (err)
1312		return err;
1313	if (decoder->packet.type == INTEL_PT_FUP) {
1314		decoder->fup_tx_flags = fup_tx_flags;
1315		decoder->set_fup_tx_flags = true;
1316		if (!(decoder->fup_tx_flags & INTEL_PT_ABORT_TX))
1317			*no_tip = true;
1318	} else {
1319		intel_pt_log_at("ERROR: Missing FUP after MODE.TSX",
1320				decoder->pos);
1321		intel_pt_update_in_tx(decoder);
1322	}
1323	return 0;
1324}
1325
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1326static void intel_pt_calc_tsc_timestamp(struct intel_pt_decoder *decoder)
1327{
1328	uint64_t timestamp;
 
1329
1330	decoder->have_tma = false;
1331
1332	if (decoder->ref_timestamp) {
1333		timestamp = decoder->packet.payload |
1334			    (decoder->ref_timestamp & (0xffULL << 56));
1335		if (timestamp < decoder->ref_timestamp) {
1336			if (decoder->ref_timestamp - timestamp > (1ULL << 55))
1337				timestamp += (1ULL << 56);
1338		} else {
1339			if (timestamp - decoder->ref_timestamp > (1ULL << 55))
1340				timestamp -= (1ULL << 56);
1341		}
1342		decoder->tsc_timestamp = timestamp;
1343		decoder->timestamp = timestamp;
1344		decoder->ref_timestamp = 0;
1345		decoder->timestamp_insn_cnt = 0;
1346	} else if (decoder->timestamp) {
1347		timestamp = decoder->packet.payload |
1348			    (decoder->timestamp & (0xffULL << 56));
1349		decoder->tsc_timestamp = timestamp;
1350		if (timestamp < decoder->timestamp &&
1351		    decoder->timestamp - timestamp < decoder->tsc_slip) {
1352			intel_pt_log_to("Suppressing backwards timestamp",
1353					timestamp);
1354			timestamp = decoder->timestamp;
1355		}
1356		if (timestamp < decoder->timestamp) {
1357			intel_pt_log_to("Wraparound timestamp", timestamp);
1358			timestamp += (1ULL << 56);
1359			decoder->tsc_timestamp = timestamp;
 
 
 
 
 
 
 
1360		}
 
 
 
 
1361		decoder->timestamp = timestamp;
1362		decoder->timestamp_insn_cnt = 0;
1363	}
1364
1365	if (decoder->last_packet_type == INTEL_PT_CYC) {
1366		decoder->cyc_ref_timestamp = decoder->timestamp;
1367		decoder->cycle_cnt = 0;
1368		decoder->have_calc_cyc_to_tsc = false;
1369		intel_pt_calc_cyc_to_tsc(decoder, false);
1370	}
1371
1372	intel_pt_log_to("Setting timestamp", decoder->timestamp);
1373}
1374
1375static int intel_pt_overflow(struct intel_pt_decoder *decoder)
1376{
1377	intel_pt_log("ERROR: Buffer overflow\n");
1378	intel_pt_clear_tx_flags(decoder);
1379	decoder->have_tma = false;
1380	decoder->cbr = 0;
1381	decoder->timestamp_insn_cnt = 0;
1382	decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
 
 
 
 
1383	decoder->overflow = true;
1384	return -EOVERFLOW;
1385}
1386
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1387static void intel_pt_calc_tma(struct intel_pt_decoder *decoder)
1388{
1389	uint32_t ctc = decoder->packet.payload;
1390	uint32_t fc = decoder->packet.count;
1391	uint32_t ctc_rem = ctc & decoder->ctc_rem_mask;
1392
1393	if (!decoder->tsc_ctc_ratio_d)
1394		return;
1395
 
 
 
 
 
1396	decoder->last_mtc = (ctc >> decoder->mtc_shift) & 0xff;
 
1397	decoder->ctc_timestamp = decoder->tsc_timestamp - fc;
1398	if (decoder->tsc_ctc_mult) {
1399		decoder->ctc_timestamp -= ctc_rem * decoder->tsc_ctc_mult;
1400	} else {
1401		decoder->ctc_timestamp -= multdiv(ctc_rem,
1402						  decoder->tsc_ctc_ratio_n,
1403						  decoder->tsc_ctc_ratio_d);
1404	}
1405	decoder->ctc_delta = 0;
1406	decoder->have_tma = true;
1407	decoder->fixup_last_mtc = true;
1408	intel_pt_log("CTC timestamp " x64_fmt " last MTC %#x  CTC rem %#x\n",
1409		     decoder->ctc_timestamp, decoder->last_mtc, ctc_rem);
1410}
1411
1412static void intel_pt_calc_mtc_timestamp(struct intel_pt_decoder *decoder)
1413{
1414	uint64_t timestamp;
1415	uint32_t mtc, mtc_delta;
1416
1417	if (!decoder->have_tma)
1418		return;
1419
1420	mtc = decoder->packet.payload;
1421
1422	if (decoder->mtc_shift > 8 && decoder->fixup_last_mtc) {
1423		decoder->fixup_last_mtc = false;
1424		intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
1425					&decoder->last_mtc);
1426	}
1427
1428	if (mtc > decoder->last_mtc)
1429		mtc_delta = mtc - decoder->last_mtc;
1430	else
1431		mtc_delta = mtc + 256 - decoder->last_mtc;
1432
1433	decoder->ctc_delta += mtc_delta << decoder->mtc_shift;
1434
1435	if (decoder->tsc_ctc_mult) {
1436		timestamp = decoder->ctc_timestamp +
1437			    decoder->ctc_delta * decoder->tsc_ctc_mult;
1438	} else {
1439		timestamp = decoder->ctc_timestamp +
1440			    multdiv(decoder->ctc_delta,
1441				    decoder->tsc_ctc_ratio_n,
1442				    decoder->tsc_ctc_ratio_d);
1443	}
1444
1445	if (timestamp < decoder->timestamp)
1446		intel_pt_log("Suppressing MTC timestamp " x64_fmt " less than current timestamp " x64_fmt "\n",
1447			     timestamp, decoder->timestamp);
1448	else
1449		decoder->timestamp = timestamp;
1450
 
 
1451	decoder->timestamp_insn_cnt = 0;
1452	decoder->last_mtc = mtc;
1453
1454	if (decoder->last_packet_type == INTEL_PT_CYC) {
1455		decoder->cyc_ref_timestamp = decoder->timestamp;
1456		decoder->cycle_cnt = 0;
1457		decoder->have_calc_cyc_to_tsc = false;
1458		intel_pt_calc_cyc_to_tsc(decoder, true);
1459	}
 
 
1460}
1461
1462static void intel_pt_calc_cbr(struct intel_pt_decoder *decoder)
1463{
1464	unsigned int cbr = decoder->packet.payload & 0xff;
1465
1466	decoder->cbr_payload = decoder->packet.payload;
1467
1468	if (decoder->cbr == cbr)
1469		return;
1470
1471	decoder->cbr = cbr;
1472	decoder->cbr_cyc_to_tsc = decoder->max_non_turbo_ratio_fp / cbr;
 
 
 
 
1473}
1474
1475static void intel_pt_calc_cyc_timestamp(struct intel_pt_decoder *decoder)
1476{
1477	uint64_t timestamp = decoder->cyc_ref_timestamp;
1478
1479	decoder->have_cyc = true;
1480
1481	decoder->cycle_cnt += decoder->packet.payload;
 
 
 
1482
1483	if (!decoder->cyc_ref_timestamp)
1484		return;
1485
1486	if (decoder->have_calc_cyc_to_tsc)
1487		timestamp += decoder->cycle_cnt * decoder->calc_cyc_to_tsc;
1488	else if (decoder->cbr)
1489		timestamp += decoder->cycle_cnt * decoder->cbr_cyc_to_tsc;
1490	else
1491		return;
1492
1493	if (timestamp < decoder->timestamp)
1494		intel_pt_log("Suppressing CYC timestamp " x64_fmt " less than current timestamp " x64_fmt "\n",
1495			     timestamp, decoder->timestamp);
1496	else
1497		decoder->timestamp = timestamp;
1498
1499	decoder->timestamp_insn_cnt = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1500}
1501
1502/* Walk PSB+ packets when already in sync. */
1503static int intel_pt_walk_psbend(struct intel_pt_decoder *decoder)
1504{
1505	int err;
1506
 
 
1507	while (1) {
1508		err = intel_pt_get_next_packet(decoder);
1509		if (err)
1510			return err;
1511
1512		switch (decoder->packet.type) {
1513		case INTEL_PT_PSBEND:
1514			return 0;
 
1515
1516		case INTEL_PT_TIP_PGD:
1517		case INTEL_PT_TIP_PGE:
1518		case INTEL_PT_TIP:
1519		case INTEL_PT_TNT:
1520		case INTEL_PT_TRACESTOP:
1521		case INTEL_PT_BAD:
1522		case INTEL_PT_PSB:
1523		case INTEL_PT_PTWRITE:
1524		case INTEL_PT_PTWRITE_IP:
1525		case INTEL_PT_EXSTOP:
1526		case INTEL_PT_EXSTOP_IP:
1527		case INTEL_PT_MWAIT:
1528		case INTEL_PT_PWRE:
1529		case INTEL_PT_PWRX:
 
 
 
 
 
 
 
1530			decoder->have_tma = false;
1531			intel_pt_log("ERROR: Unexpected packet\n");
1532			return -EAGAIN;
 
1533
1534		case INTEL_PT_OVF:
1535			return intel_pt_overflow(decoder);
 
1536
1537		case INTEL_PT_TSC:
1538			intel_pt_calc_tsc_timestamp(decoder);
1539			break;
1540
1541		case INTEL_PT_TMA:
1542			intel_pt_calc_tma(decoder);
1543			break;
1544
1545		case INTEL_PT_CBR:
1546			intel_pt_calc_cbr(decoder);
1547			break;
1548
1549		case INTEL_PT_MODE_EXEC:
1550			decoder->exec_mode = decoder->packet.payload;
1551			break;
1552
1553		case INTEL_PT_PIP:
1554			decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
1555			break;
1556
1557		case INTEL_PT_FUP:
1558			decoder->pge = true;
1559			if (decoder->packet.count)
1560				intel_pt_set_last_ip(decoder);
 
 
1561			break;
1562
1563		case INTEL_PT_MODE_TSX:
1564			intel_pt_update_in_tx(decoder);
1565			break;
1566
1567		case INTEL_PT_MTC:
1568			intel_pt_calc_mtc_timestamp(decoder);
1569			if (decoder->period_type == INTEL_PT_PERIOD_MTC)
1570				decoder->state.type |= INTEL_PT_INSTRUCTION;
1571			break;
1572
1573		case INTEL_PT_CYC:
 
 
 
1574		case INTEL_PT_VMCS:
1575		case INTEL_PT_MNT:
1576		case INTEL_PT_PAD:
1577		default:
1578			break;
1579		}
1580	}
 
 
 
 
1581}
1582
1583static int intel_pt_walk_fup_tip(struct intel_pt_decoder *decoder)
1584{
1585	int err;
1586
1587	if (decoder->tx_flags & INTEL_PT_ABORT_TX) {
1588		decoder->tx_flags = 0;
1589		decoder->state.flags &= ~INTEL_PT_IN_TX;
1590		decoder->state.flags |= INTEL_PT_ABORT_TX;
1591	} else {
1592		decoder->state.flags |= INTEL_PT_ASYNC;
1593	}
1594
1595	while (1) {
1596		err = intel_pt_get_next_packet(decoder);
1597		if (err)
1598			return err;
1599
1600		switch (decoder->packet.type) {
1601		case INTEL_PT_TNT:
1602		case INTEL_PT_FUP:
1603		case INTEL_PT_TRACESTOP:
1604		case INTEL_PT_PSB:
1605		case INTEL_PT_TSC:
1606		case INTEL_PT_TMA:
1607		case INTEL_PT_CBR:
1608		case INTEL_PT_MODE_TSX:
1609		case INTEL_PT_BAD:
1610		case INTEL_PT_PSBEND:
1611		case INTEL_PT_PTWRITE:
1612		case INTEL_PT_PTWRITE_IP:
1613		case INTEL_PT_EXSTOP:
1614		case INTEL_PT_EXSTOP_IP:
1615		case INTEL_PT_MWAIT:
1616		case INTEL_PT_PWRE:
1617		case INTEL_PT_PWRX:
 
 
 
 
 
 
 
1618			intel_pt_log("ERROR: Missing TIP after FUP\n");
1619			decoder->pkt_state = INTEL_PT_STATE_ERR3;
1620			decoder->pkt_step = 0;
1621			return -ENOENT;
1622
 
 
 
 
1623		case INTEL_PT_OVF:
1624			return intel_pt_overflow(decoder);
1625
1626		case INTEL_PT_TIP_PGD:
1627			decoder->state.from_ip = decoder->ip;
1628			decoder->state.to_ip = 0;
1629			if (decoder->packet.count != 0) {
 
1630				intel_pt_set_ip(decoder);
1631				intel_pt_log("Omitting PGD ip " x64_fmt "\n",
1632					     decoder->ip);
1633			}
1634			decoder->pge = false;
1635			decoder->continuous_period = false;
 
 
1636			return 0;
1637
1638		case INTEL_PT_TIP_PGE:
1639			decoder->pge = true;
1640			intel_pt_log("Omitting PGE ip " x64_fmt "\n",
1641				     decoder->ip);
1642			decoder->state.from_ip = 0;
1643			if (decoder->packet.count == 0) {
1644				decoder->state.to_ip = 0;
1645			} else {
1646				intel_pt_set_ip(decoder);
1647				decoder->state.to_ip = decoder->ip;
1648			}
 
 
 
1649			return 0;
1650
1651		case INTEL_PT_TIP:
1652			decoder->state.from_ip = decoder->ip;
1653			if (decoder->packet.count == 0) {
1654				decoder->state.to_ip = 0;
1655			} else {
1656				intel_pt_set_ip(decoder);
1657				decoder->state.to_ip = decoder->ip;
1658			}
 
 
1659			return 0;
1660
1661		case INTEL_PT_PIP:
1662			decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
1663			break;
1664
1665		case INTEL_PT_MTC:
1666			intel_pt_calc_mtc_timestamp(decoder);
1667			if (decoder->period_type == INTEL_PT_PERIOD_MTC)
1668				decoder->state.type |= INTEL_PT_INSTRUCTION;
1669			break;
1670
1671		case INTEL_PT_CYC:
1672			intel_pt_calc_cyc_timestamp(decoder);
1673			break;
1674
1675		case INTEL_PT_MODE_EXEC:
1676			decoder->exec_mode = decoder->packet.payload;
1677			break;
1678
1679		case INTEL_PT_VMCS:
1680		case INTEL_PT_MNT:
1681		case INTEL_PT_PAD:
1682			break;
1683
1684		default:
1685			return intel_pt_bug(decoder);
1686		}
1687	}
1688}
1689
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1690static int intel_pt_walk_trace(struct intel_pt_decoder *decoder)
1691{
 
1692	bool no_tip = false;
1693	int err;
1694
1695	while (1) {
1696		err = intel_pt_get_next_packet(decoder);
1697		if (err)
1698			return err;
1699next:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1700		switch (decoder->packet.type) {
1701		case INTEL_PT_TNT:
1702			if (!decoder->packet.count)
1703				break;
1704			decoder->tnt = decoder->packet;
1705			decoder->pkt_state = INTEL_PT_STATE_TNT;
1706			err = intel_pt_walk_tnt(decoder);
1707			if (err == -EAGAIN)
1708				break;
1709			return err;
1710
1711		case INTEL_PT_TIP_PGD:
1712			if (decoder->packet.count != 0)
1713				intel_pt_set_last_ip(decoder);
1714			decoder->pkt_state = INTEL_PT_STATE_TIP_PGD;
1715			return intel_pt_walk_tip(decoder);
1716
1717		case INTEL_PT_TIP_PGE: {
1718			decoder->pge = true;
 
 
 
1719			if (decoder->packet.count == 0) {
1720				intel_pt_log_at("Skipping zero TIP.PGE",
1721						decoder->pos);
1722				break;
1723			}
 
1724			intel_pt_set_ip(decoder);
1725			decoder->state.from_ip = 0;
1726			decoder->state.to_ip = decoder->ip;
 
 
 
 
 
 
 
1727			return 0;
1728		}
1729
1730		case INTEL_PT_OVF:
1731			return intel_pt_overflow(decoder);
1732
1733		case INTEL_PT_TIP:
1734			if (decoder->packet.count != 0)
1735				intel_pt_set_last_ip(decoder);
1736			decoder->pkt_state = INTEL_PT_STATE_TIP;
1737			return intel_pt_walk_tip(decoder);
1738
1739		case INTEL_PT_FUP:
1740			if (decoder->packet.count == 0) {
1741				intel_pt_log_at("Skipping zero FUP",
1742						decoder->pos);
1743				no_tip = false;
1744				break;
1745			}
1746			intel_pt_set_last_ip(decoder);
1747			if (!decoder->branch_enable) {
1748				decoder->ip = decoder->last_ip;
1749				if (intel_pt_fup_event(decoder))
1750					return 0;
1751				no_tip = false;
1752				break;
1753			}
1754			if (decoder->set_fup_mwait)
1755				no_tip = true;
 
 
 
 
1756			err = intel_pt_walk_fup(decoder);
1757			if (err != -EAGAIN) {
1758				if (err)
1759					return err;
1760				if (no_tip)
1761					decoder->pkt_state =
1762						INTEL_PT_STATE_FUP_NO_TIP;
1763				else
1764					decoder->pkt_state = INTEL_PT_STATE_FUP;
1765				return 0;
1766			}
1767			if (no_tip) {
1768				no_tip = false;
1769				break;
1770			}
1771			return intel_pt_walk_fup_tip(decoder);
1772
1773		case INTEL_PT_TRACESTOP:
1774			decoder->pge = false;
1775			decoder->continuous_period = false;
1776			intel_pt_clear_tx_flags(decoder);
1777			decoder->have_tma = false;
1778			break;
1779
1780		case INTEL_PT_PSB:
1781			decoder->last_ip = 0;
1782			decoder->have_last_ip = true;
1783			intel_pt_clear_stack(&decoder->stack);
1784			err = intel_pt_walk_psbend(decoder);
 
1785			if (err == -EAGAIN)
1786				goto next;
1787			if (err)
1788				return err;
1789			break;
1790
1791		case INTEL_PT_PIP:
1792			decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
1793			break;
1794
1795		case INTEL_PT_MTC:
1796			intel_pt_calc_mtc_timestamp(decoder);
1797			if (decoder->period_type != INTEL_PT_PERIOD_MTC)
1798				break;
1799			/*
1800			 * Ensure that there has been an instruction since the
1801			 * last MTC.
1802			 */
1803			if (!decoder->mtc_insn)
1804				break;
1805			decoder->mtc_insn = false;
1806			/* Ensure that there is a timestamp */
1807			if (!decoder->timestamp)
1808				break;
1809			decoder->state.type = INTEL_PT_INSTRUCTION;
1810			decoder->state.from_ip = decoder->ip;
1811			decoder->state.to_ip = 0;
1812			decoder->mtc_insn = false;
1813			return 0;
1814
1815		case INTEL_PT_TSC:
1816			intel_pt_calc_tsc_timestamp(decoder);
1817			break;
1818
1819		case INTEL_PT_TMA:
1820			intel_pt_calc_tma(decoder);
1821			break;
1822
1823		case INTEL_PT_CYC:
1824			intel_pt_calc_cyc_timestamp(decoder);
1825			break;
1826
1827		case INTEL_PT_CBR:
1828			intel_pt_calc_cbr(decoder);
1829			if (!decoder->branch_enable &&
1830			    decoder->cbr != decoder->cbr_seen) {
1831				decoder->cbr_seen = decoder->cbr;
1832				decoder->state.type = INTEL_PT_CBR_CHG;
1833				decoder->state.from_ip = decoder->ip;
1834				decoder->state.to_ip = 0;
1835				decoder->state.cbr_payload =
1836							decoder->packet.payload;
1837				return 0;
1838			}
1839			break;
1840
1841		case INTEL_PT_MODE_EXEC:
1842			decoder->exec_mode = decoder->packet.payload;
1843			break;
 
 
 
 
 
 
 
1844
1845		case INTEL_PT_MODE_TSX:
1846			/* MODE_TSX need not be followed by FUP */
1847			if (!decoder->pge) {
1848				intel_pt_update_in_tx(decoder);
1849				break;
1850			}
1851			err = intel_pt_mode_tsx(decoder, &no_tip);
1852			if (err)
1853				return err;
1854			goto next;
1855
1856		case INTEL_PT_BAD: /* Does not happen */
1857			return intel_pt_bug(decoder);
1858
1859		case INTEL_PT_PSBEND:
1860		case INTEL_PT_VMCS:
1861		case INTEL_PT_MNT:
1862		case INTEL_PT_PAD:
1863			break;
1864
1865		case INTEL_PT_PTWRITE_IP:
1866			decoder->fup_ptw_payload = decoder->packet.payload;
1867			err = intel_pt_get_next_packet(decoder);
1868			if (err)
1869				return err;
1870			if (decoder->packet.type == INTEL_PT_FUP) {
1871				decoder->set_fup_ptw = true;
1872				no_tip = true;
1873			} else {
1874				intel_pt_log_at("ERROR: Missing FUP after PTWRITE",
1875						decoder->pos);
1876			}
1877			goto next;
1878
1879		case INTEL_PT_PTWRITE:
1880			decoder->state.type = INTEL_PT_PTW;
1881			decoder->state.from_ip = decoder->ip;
1882			decoder->state.to_ip = 0;
1883			decoder->state.ptw_payload = decoder->packet.payload;
1884			return 0;
1885
1886		case INTEL_PT_MWAIT:
1887			decoder->fup_mwait_payload = decoder->packet.payload;
1888			decoder->set_fup_mwait = true;
1889			break;
1890
1891		case INTEL_PT_PWRE:
1892			if (decoder->set_fup_mwait) {
1893				decoder->fup_pwre_payload =
1894							decoder->packet.payload;
1895				decoder->set_fup_pwre = true;
1896				break;
1897			}
1898			decoder->state.type = INTEL_PT_PWR_ENTRY;
1899			decoder->state.from_ip = decoder->ip;
1900			decoder->state.to_ip = 0;
1901			decoder->state.pwrx_payload = decoder->packet.payload;
1902			return 0;
1903
1904		case INTEL_PT_EXSTOP_IP:
1905			err = intel_pt_get_next_packet(decoder);
1906			if (err)
1907				return err;
1908			if (decoder->packet.type == INTEL_PT_FUP) {
1909				decoder->set_fup_exstop = true;
1910				no_tip = true;
1911			} else {
1912				intel_pt_log_at("ERROR: Missing FUP after EXSTOP",
1913						decoder->pos);
1914			}
1915			goto next;
1916
1917		case INTEL_PT_EXSTOP:
1918			decoder->state.type = INTEL_PT_EX_STOP;
1919			decoder->state.from_ip = decoder->ip;
1920			decoder->state.to_ip = 0;
1921			return 0;
1922
1923		case INTEL_PT_PWRX:
1924			decoder->state.type = INTEL_PT_PWR_EXIT;
1925			decoder->state.from_ip = decoder->ip;
1926			decoder->state.to_ip = 0;
1927			decoder->state.pwrx_payload = decoder->packet.payload;
1928			return 0;
1929
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1930		default:
1931			return intel_pt_bug(decoder);
1932		}
1933	}
1934}
1935
1936static inline bool intel_pt_have_ip(struct intel_pt_decoder *decoder)
1937{
1938	return decoder->packet.count &&
1939	       (decoder->have_last_ip || decoder->packet.count == 3 ||
1940		decoder->packet.count == 6);
1941}
1942
1943/* Walk PSB+ packets to get in sync. */
1944static int intel_pt_walk_psb(struct intel_pt_decoder *decoder)
1945{
1946	int err;
1947
 
 
1948	while (1) {
1949		err = intel_pt_get_next_packet(decoder);
1950		if (err)
1951			return err;
1952
1953		switch (decoder->packet.type) {
1954		case INTEL_PT_TIP_PGD:
1955			decoder->continuous_period = false;
1956			__fallthrough;
1957		case INTEL_PT_TIP_PGE:
1958		case INTEL_PT_TIP:
1959		case INTEL_PT_PTWRITE:
1960		case INTEL_PT_PTWRITE_IP:
1961		case INTEL_PT_EXSTOP:
1962		case INTEL_PT_EXSTOP_IP:
1963		case INTEL_PT_MWAIT:
1964		case INTEL_PT_PWRE:
1965		case INTEL_PT_PWRX:
 
 
 
 
 
 
 
1966			intel_pt_log("ERROR: Unexpected packet\n");
1967			return -ENOENT;
 
1968
1969		case INTEL_PT_FUP:
1970			decoder->pge = true;
1971			if (intel_pt_have_ip(decoder)) {
1972				uint64_t current_ip = decoder->ip;
1973
1974				intel_pt_set_ip(decoder);
 
1975				if (current_ip)
1976					intel_pt_log_to("Setting IP",
1977							decoder->ip);
1978			}
1979			break;
1980
1981		case INTEL_PT_MTC:
1982			intel_pt_calc_mtc_timestamp(decoder);
1983			break;
1984
1985		case INTEL_PT_TSC:
1986			intel_pt_calc_tsc_timestamp(decoder);
1987			break;
1988
1989		case INTEL_PT_TMA:
1990			intel_pt_calc_tma(decoder);
1991			break;
1992
1993		case INTEL_PT_CYC:
1994			intel_pt_calc_cyc_timestamp(decoder);
1995			break;
1996
1997		case INTEL_PT_CBR:
1998			intel_pt_calc_cbr(decoder);
1999			break;
2000
2001		case INTEL_PT_PIP:
2002			decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
2003			break;
2004
2005		case INTEL_PT_MODE_EXEC:
2006			decoder->exec_mode = decoder->packet.payload;
2007			break;
2008
2009		case INTEL_PT_MODE_TSX:
2010			intel_pt_update_in_tx(decoder);
2011			break;
2012
2013		case INTEL_PT_TRACESTOP:
2014			decoder->pge = false;
2015			decoder->continuous_period = false;
2016			intel_pt_clear_tx_flags(decoder);
2017			__fallthrough;
2018
2019		case INTEL_PT_TNT:
2020			decoder->have_tma = false;
2021			intel_pt_log("ERROR: Unexpected packet\n");
2022			if (decoder->ip)
2023				decoder->pkt_state = INTEL_PT_STATE_ERR4;
2024			else
2025				decoder->pkt_state = INTEL_PT_STATE_ERR3;
2026			return -ENOENT;
 
2027
2028		case INTEL_PT_BAD: /* Does not happen */
2029			return intel_pt_bug(decoder);
 
2030
2031		case INTEL_PT_OVF:
2032			return intel_pt_overflow(decoder);
 
2033
2034		case INTEL_PT_PSBEND:
2035			return 0;
 
2036
2037		case INTEL_PT_PSB:
2038		case INTEL_PT_VMCS:
2039		case INTEL_PT_MNT:
2040		case INTEL_PT_PAD:
2041		default:
2042			break;
2043		}
2044	}
 
 
 
 
2045}
2046
2047static int intel_pt_walk_to_ip(struct intel_pt_decoder *decoder)
2048{
2049	int err;
2050
2051	while (1) {
2052		err = intel_pt_get_next_packet(decoder);
2053		if (err)
2054			return err;
2055
2056		switch (decoder->packet.type) {
2057		case INTEL_PT_TIP_PGD:
2058			decoder->continuous_period = false;
2059			__fallthrough;
 
 
 
 
 
 
 
2060		case INTEL_PT_TIP_PGE:
 
 
 
 
 
 
 
 
 
2061		case INTEL_PT_TIP:
2062			decoder->pge = decoder->packet.type != INTEL_PT_TIP_PGD;
2063			if (intel_pt_have_ip(decoder))
2064				intel_pt_set_ip(decoder);
2065			if (decoder->ip)
2066				return 0;
2067			break;
2068
2069		case INTEL_PT_FUP:
2070			if (intel_pt_have_ip(decoder))
2071				intel_pt_set_ip(decoder);
2072			if (decoder->ip)
2073				return 0;
2074			break;
2075
2076		case INTEL_PT_MTC:
2077			intel_pt_calc_mtc_timestamp(decoder);
2078			break;
2079
2080		case INTEL_PT_TSC:
2081			intel_pt_calc_tsc_timestamp(decoder);
2082			break;
2083
2084		case INTEL_PT_TMA:
2085			intel_pt_calc_tma(decoder);
2086			break;
2087
2088		case INTEL_PT_CYC:
2089			intel_pt_calc_cyc_timestamp(decoder);
2090			break;
2091
2092		case INTEL_PT_CBR:
2093			intel_pt_calc_cbr(decoder);
2094			break;
2095
2096		case INTEL_PT_PIP:
2097			decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
2098			break;
2099
2100		case INTEL_PT_MODE_EXEC:
2101			decoder->exec_mode = decoder->packet.payload;
2102			break;
2103
2104		case INTEL_PT_MODE_TSX:
2105			intel_pt_update_in_tx(decoder);
2106			break;
2107
2108		case INTEL_PT_OVF:
2109			return intel_pt_overflow(decoder);
2110
2111		case INTEL_PT_BAD: /* Does not happen */
2112			return intel_pt_bug(decoder);
2113
2114		case INTEL_PT_TRACESTOP:
2115			decoder->pge = false;
2116			decoder->continuous_period = false;
2117			intel_pt_clear_tx_flags(decoder);
2118			decoder->have_tma = false;
2119			break;
2120
2121		case INTEL_PT_PSB:
 
 
2122			decoder->last_ip = 0;
2123			decoder->have_last_ip = true;
2124			intel_pt_clear_stack(&decoder->stack);
2125			err = intel_pt_walk_psb(decoder);
2126			if (err)
2127				return err;
2128			if (decoder->ip) {
2129				/* Do not have a sample */
2130				decoder->state.type = 0;
2131				return 0;
2132			}
2133			break;
2134
2135		case INTEL_PT_TNT:
2136		case INTEL_PT_PSBEND:
2137		case INTEL_PT_VMCS:
2138		case INTEL_PT_MNT:
2139		case INTEL_PT_PAD:
2140		case INTEL_PT_PTWRITE:
2141		case INTEL_PT_PTWRITE_IP:
2142		case INTEL_PT_EXSTOP:
2143		case INTEL_PT_EXSTOP_IP:
2144		case INTEL_PT_MWAIT:
2145		case INTEL_PT_PWRE:
2146		case INTEL_PT_PWRX:
 
 
 
 
 
 
 
2147		default:
2148			break;
2149		}
2150	}
2151}
2152
2153static int intel_pt_sync_ip(struct intel_pt_decoder *decoder)
2154{
2155	int err;
2156
2157	decoder->set_fup_tx_flags = false;
2158	decoder->set_fup_ptw = false;
2159	decoder->set_fup_mwait = false;
2160	decoder->set_fup_pwre = false;
2161	decoder->set_fup_exstop = false;
2162
2163	if (!decoder->branch_enable) {
2164		decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2165		decoder->overflow = false;
2166		decoder->state.type = 0; /* Do not have a sample */
2167		return 0;
2168	}
2169
2170	intel_pt_log("Scanning for full IP\n");
2171	err = intel_pt_walk_to_ip(decoder);
2172	if (err)
2173		return err;
2174
2175	decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2176	decoder->overflow = false;
 
 
 
2177
2178	decoder->state.from_ip = 0;
2179	decoder->state.to_ip = decoder->ip;
2180	intel_pt_log_to("Setting IP", decoder->ip);
2181
2182	return 0;
2183}
2184
2185static int intel_pt_part_psb(struct intel_pt_decoder *decoder)
2186{
2187	const unsigned char *end = decoder->buf + decoder->len;
2188	size_t i;
2189
2190	for (i = INTEL_PT_PSB_LEN - 1; i; i--) {
2191		if (i > decoder->len)
2192			continue;
2193		if (!memcmp(end - i, INTEL_PT_PSB_STR, i))
2194			return i;
2195	}
2196	return 0;
2197}
2198
2199static int intel_pt_rest_psb(struct intel_pt_decoder *decoder, int part_psb)
2200{
2201	size_t rest_psb = INTEL_PT_PSB_LEN - part_psb;
2202	const char *psb = INTEL_PT_PSB_STR;
2203
2204	if (rest_psb > decoder->len ||
2205	    memcmp(decoder->buf, psb + part_psb, rest_psb))
2206		return 0;
2207
2208	return rest_psb;
2209}
2210
2211static int intel_pt_get_split_psb(struct intel_pt_decoder *decoder,
2212				  int part_psb)
2213{
2214	int rest_psb, ret;
2215
2216	decoder->pos += decoder->len;
2217	decoder->len = 0;
2218
2219	ret = intel_pt_get_next_data(decoder);
2220	if (ret)
2221		return ret;
2222
2223	rest_psb = intel_pt_rest_psb(decoder, part_psb);
2224	if (!rest_psb)
2225		return 0;
2226
2227	decoder->pos -= part_psb;
2228	decoder->next_buf = decoder->buf + rest_psb;
2229	decoder->next_len = decoder->len - rest_psb;
2230	memcpy(decoder->temp_buf, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
2231	decoder->buf = decoder->temp_buf;
2232	decoder->len = INTEL_PT_PSB_LEN;
2233
2234	return 0;
2235}
2236
2237static int intel_pt_scan_for_psb(struct intel_pt_decoder *decoder)
2238{
2239	unsigned char *next;
2240	int ret;
2241
2242	intel_pt_log("Scanning for PSB\n");
2243	while (1) {
2244		if (!decoder->len) {
2245			ret = intel_pt_get_next_data(decoder);
2246			if (ret)
2247				return ret;
2248		}
2249
2250		next = memmem(decoder->buf, decoder->len, INTEL_PT_PSB_STR,
2251			      INTEL_PT_PSB_LEN);
2252		if (!next) {
2253			int part_psb;
2254
2255			part_psb = intel_pt_part_psb(decoder);
2256			if (part_psb) {
2257				ret = intel_pt_get_split_psb(decoder, part_psb);
2258				if (ret)
2259					return ret;
2260			} else {
2261				decoder->pos += decoder->len;
2262				decoder->len = 0;
2263			}
2264			continue;
2265		}
2266
2267		decoder->pkt_step = next - decoder->buf;
2268		return intel_pt_get_next_packet(decoder);
2269	}
2270}
2271
2272static int intel_pt_sync(struct intel_pt_decoder *decoder)
2273{
2274	int err;
2275
2276	decoder->pge = false;
2277	decoder->continuous_period = false;
2278	decoder->have_last_ip = false;
2279	decoder->last_ip = 0;
 
2280	decoder->ip = 0;
2281	intel_pt_clear_stack(&decoder->stack);
2282
2283	err = intel_pt_scan_for_psb(decoder);
2284	if (err)
2285		return err;
2286
 
 
 
 
 
 
 
 
 
2287	decoder->have_last_ip = true;
2288	decoder->pkt_state = INTEL_PT_STATE_NO_IP;
2289
2290	err = intel_pt_walk_psb(decoder);
2291	if (err)
2292		return err;
2293
 
 
 
 
2294	if (decoder->ip) {
2295		decoder->state.type = 0; /* Do not have a sample */
2296		decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2297	} else {
2298		return intel_pt_sync_ip(decoder);
 
 
 
 
2299	}
2300
2301	return 0;
2302}
2303
2304static uint64_t intel_pt_est_timestamp(struct intel_pt_decoder *decoder)
2305{
2306	uint64_t est = decoder->sample_insn_cnt << 1;
2307
2308	if (!decoder->cbr || !decoder->max_non_turbo_ratio)
2309		goto out;
2310
2311	est *= decoder->max_non_turbo_ratio;
2312	est /= decoder->cbr;
2313out:
2314	return decoder->sample_timestamp + est;
2315}
2316
2317const struct intel_pt_state *intel_pt_decode(struct intel_pt_decoder *decoder)
2318{
2319	int err;
2320
2321	do {
2322		decoder->state.type = INTEL_PT_BRANCH;
2323		decoder->state.flags = 0;
2324
2325		switch (decoder->pkt_state) {
2326		case INTEL_PT_STATE_NO_PSB:
2327			err = intel_pt_sync(decoder);
2328			break;
2329		case INTEL_PT_STATE_NO_IP:
2330			decoder->have_last_ip = false;
2331			decoder->last_ip = 0;
2332			decoder->ip = 0;
2333			__fallthrough;
2334		case INTEL_PT_STATE_ERR_RESYNC:
2335			err = intel_pt_sync_ip(decoder);
2336			break;
2337		case INTEL_PT_STATE_IN_SYNC:
2338			err = intel_pt_walk_trace(decoder);
2339			break;
2340		case INTEL_PT_STATE_TNT:
 
2341			err = intel_pt_walk_tnt(decoder);
2342			if (err == -EAGAIN)
2343				err = intel_pt_walk_trace(decoder);
2344			break;
2345		case INTEL_PT_STATE_TIP:
2346		case INTEL_PT_STATE_TIP_PGD:
2347			err = intel_pt_walk_tip(decoder);
2348			break;
2349		case INTEL_PT_STATE_FUP:
2350			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2351			err = intel_pt_walk_fup(decoder);
2352			if (err == -EAGAIN)
2353				err = intel_pt_walk_fup_tip(decoder);
2354			else if (!err)
2355				decoder->pkt_state = INTEL_PT_STATE_FUP;
2356			break;
2357		case INTEL_PT_STATE_FUP_NO_TIP:
2358			decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2359			err = intel_pt_walk_fup(decoder);
2360			if (err == -EAGAIN)
2361				err = intel_pt_walk_trace(decoder);
2362			break;
 
 
 
 
 
 
 
 
 
2363		default:
2364			err = intel_pt_bug(decoder);
2365			break;
2366		}
2367	} while (err == -ENOLINK);
2368
2369	if (err) {
2370		decoder->state.err = intel_pt_ext_err(err);
2371		decoder->state.from_ip = decoder->ip;
2372		decoder->sample_timestamp = decoder->timestamp;
2373		decoder->sample_insn_cnt = decoder->timestamp_insn_cnt;
 
 
2374	} else {
2375		decoder->state.err = 0;
2376		if (decoder->cbr != decoder->cbr_seen && decoder->state.type) {
2377			decoder->cbr_seen = decoder->cbr;
 
 
 
 
2378			decoder->state.type |= INTEL_PT_CBR_CHG;
2379			decoder->state.cbr_payload = decoder->cbr_payload;
 
2380		}
2381		if (intel_pt_sample_time(decoder->pkt_state)) {
2382			decoder->sample_timestamp = decoder->timestamp;
2383			decoder->sample_insn_cnt = decoder->timestamp_insn_cnt;
 
 
 
 
2384		}
 
 
 
 
 
 
2385	}
2386
 
 
 
 
 
 
 
 
2387	decoder->state.timestamp = decoder->sample_timestamp;
2388	decoder->state.est_timestamp = intel_pt_est_timestamp(decoder);
2389	decoder->state.cr3 = decoder->cr3;
2390	decoder->state.tot_insn_cnt = decoder->tot_insn_cnt;
 
2391
2392	return &decoder->state;
2393}
2394
2395/**
2396 * intel_pt_next_psb - move buffer pointer to the start of the next PSB packet.
2397 * @buf: pointer to buffer pointer
2398 * @len: size of buffer
2399 *
2400 * Updates the buffer pointer to point to the start of the next PSB packet if
2401 * there is one, otherwise the buffer pointer is unchanged.  If @buf is updated,
2402 * @len is adjusted accordingly.
2403 *
2404 * Return: %true if a PSB packet is found, %false otherwise.
2405 */
2406static bool intel_pt_next_psb(unsigned char **buf, size_t *len)
2407{
2408	unsigned char *next;
2409
2410	next = memmem(*buf, *len, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
2411	if (next) {
2412		*len -= next - *buf;
2413		*buf = next;
2414		return true;
2415	}
2416	return false;
2417}
2418
2419/**
2420 * intel_pt_step_psb - move buffer pointer to the start of the following PSB
2421 *                     packet.
2422 * @buf: pointer to buffer pointer
2423 * @len: size of buffer
2424 *
2425 * Updates the buffer pointer to point to the start of the following PSB packet
2426 * (skipping the PSB at @buf itself) if there is one, otherwise the buffer
2427 * pointer is unchanged.  If @buf is updated, @len is adjusted accordingly.
2428 *
2429 * Return: %true if a PSB packet is found, %false otherwise.
2430 */
2431static bool intel_pt_step_psb(unsigned char **buf, size_t *len)
2432{
2433	unsigned char *next;
2434
2435	if (!*len)
2436		return false;
2437
2438	next = memmem(*buf + 1, *len - 1, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
2439	if (next) {
2440		*len -= next - *buf;
2441		*buf = next;
2442		return true;
2443	}
2444	return false;
2445}
2446
2447/**
2448 * intel_pt_last_psb - find the last PSB packet in a buffer.
2449 * @buf: buffer
2450 * @len: size of buffer
2451 *
2452 * This function finds the last PSB in a buffer.
2453 *
2454 * Return: A pointer to the last PSB in @buf if found, %NULL otherwise.
2455 */
2456static unsigned char *intel_pt_last_psb(unsigned char *buf, size_t len)
2457{
2458	const char *n = INTEL_PT_PSB_STR;
2459	unsigned char *p;
2460	size_t k;
2461
2462	if (len < INTEL_PT_PSB_LEN)
2463		return NULL;
2464
2465	k = len - INTEL_PT_PSB_LEN + 1;
2466	while (1) {
2467		p = memrchr(buf, n[0], k);
2468		if (!p)
2469			return NULL;
2470		if (!memcmp(p + 1, n + 1, INTEL_PT_PSB_LEN - 1))
2471			return p;
2472		k = p - buf;
2473		if (!k)
2474			return NULL;
2475	}
2476}
2477
2478/**
2479 * intel_pt_next_tsc - find and return next TSC.
2480 * @buf: buffer
2481 * @len: size of buffer
2482 * @tsc: TSC value returned
2483 * @rem: returns remaining size when TSC is found
2484 *
2485 * Find a TSC packet in @buf and return the TSC value.  This function assumes
2486 * that @buf starts at a PSB and that PSB+ will contain TSC and so stops if a
2487 * PSBEND packet is found.
2488 *
2489 * Return: %true if TSC is found, false otherwise.
2490 */
2491static bool intel_pt_next_tsc(unsigned char *buf, size_t len, uint64_t *tsc,
2492			      size_t *rem)
2493{
 
2494	struct intel_pt_pkt packet;
2495	int ret;
2496
2497	while (len) {
2498		ret = intel_pt_get_packet(buf, len, &packet);
2499		if (ret <= 0)
2500			return false;
2501		if (packet.type == INTEL_PT_TSC) {
2502			*tsc = packet.payload;
2503			*rem = len;
2504			return true;
2505		}
2506		if (packet.type == INTEL_PT_PSBEND)
2507			return false;
2508		buf += ret;
2509		len -= ret;
2510	}
2511	return false;
2512}
2513
2514/**
2515 * intel_pt_tsc_cmp - compare 7-byte TSCs.
2516 * @tsc1: first TSC to compare
2517 * @tsc2: second TSC to compare
2518 *
2519 * This function compares 7-byte TSC values allowing for the possibility that
2520 * TSC wrapped around.  Generally it is not possible to know if TSC has wrapped
2521 * around so for that purpose this function assumes the absolute difference is
2522 * less than half the maximum difference.
2523 *
2524 * Return: %-1 if @tsc1 is before @tsc2, %0 if @tsc1 == @tsc2, %1 if @tsc1 is
2525 * after @tsc2.
2526 */
2527static int intel_pt_tsc_cmp(uint64_t tsc1, uint64_t tsc2)
2528{
2529	const uint64_t halfway = (1ULL << 55);
2530
2531	if (tsc1 == tsc2)
2532		return 0;
2533
2534	if (tsc1 < tsc2) {
2535		if (tsc2 - tsc1 < halfway)
2536			return -1;
2537		else
2538			return 1;
2539	} else {
2540		if (tsc1 - tsc2 < halfway)
2541			return 1;
2542		else
2543			return -1;
2544	}
2545}
2546
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2547/**
2548 * intel_pt_find_overlap_tsc - determine start of non-overlapped trace data
2549 *                             using TSC.
2550 * @buf_a: first buffer
2551 * @len_a: size of first buffer
2552 * @buf_b: second buffer
2553 * @len_b: size of second buffer
2554 * @consecutive: returns true if there is data in buf_b that is consecutive
2555 *               to buf_a
 
2556 *
2557 * If the trace contains TSC we can look at the last TSC of @buf_a and the
2558 * first TSC of @buf_b in order to determine if the buffers overlap, and then
2559 * walk forward in @buf_b until a later TSC is found.  A precondition is that
2560 * @buf_a and @buf_b are positioned at a PSB.
2561 *
2562 * Return: A pointer into @buf_b from where non-overlapped data starts, or
2563 * @buf_b + @len_b if there is no non-overlapped data.
2564 */
2565static unsigned char *intel_pt_find_overlap_tsc(unsigned char *buf_a,
2566						size_t len_a,
2567						unsigned char *buf_b,
2568						size_t len_b, bool *consecutive)
 
2569{
2570	uint64_t tsc_a, tsc_b;
2571	unsigned char *p;
2572	size_t len, rem_a, rem_b;
2573
2574	p = intel_pt_last_psb(buf_a, len_a);
2575	if (!p)
2576		return buf_b; /* No PSB in buf_a => no overlap */
2577
2578	len = len_a - (p - buf_a);
2579	if (!intel_pt_next_tsc(p, len, &tsc_a, &rem_a)) {
2580		/* The last PSB+ in buf_a is incomplete, so go back one more */
2581		len_a -= len;
2582		p = intel_pt_last_psb(buf_a, len_a);
2583		if (!p)
2584			return buf_b; /* No full PSB+ => assume no overlap */
2585		len = len_a - (p - buf_a);
2586		if (!intel_pt_next_tsc(p, len, &tsc_a, &rem_a))
2587			return buf_b; /* No TSC in buf_a => assume no overlap */
2588	}
2589
2590	while (1) {
2591		/* Ignore PSB+ with no TSC */
2592		if (intel_pt_next_tsc(buf_b, len_b, &tsc_b, &rem_b)) {
2593			int cmp = intel_pt_tsc_cmp(tsc_a, tsc_b);
2594
2595			/* Same TSC, so buffers are consecutive */
2596			if (!cmp && rem_b >= rem_a) {
 
 
2597				*consecutive = true;
2598				return buf_b + len_b - (rem_b - rem_a);
 
2599			}
2600			if (cmp < 0)
2601				return buf_b; /* tsc_a < tsc_b => no overlap */
2602		}
2603
2604		if (!intel_pt_step_psb(&buf_b, &len_b))
2605			return buf_b + len_b; /* No PSB in buf_b => no data */
2606	}
2607}
2608
2609/**
2610 * intel_pt_find_overlap - determine start of non-overlapped trace data.
2611 * @buf_a: first buffer
2612 * @len_a: size of first buffer
2613 * @buf_b: second buffer
2614 * @len_b: size of second buffer
2615 * @have_tsc: can use TSC packets to detect overlap
2616 * @consecutive: returns true if there is data in buf_b that is consecutive
2617 *               to buf_a
 
2618 *
2619 * When trace samples or snapshots are recorded there is the possibility that
2620 * the data overlaps.  Note that, for the purposes of decoding, data is only
2621 * useful if it begins with a PSB packet.
2622 *
2623 * Return: A pointer into @buf_b from where non-overlapped data starts, or
2624 * @buf_b + @len_b if there is no non-overlapped data.
2625 */
2626unsigned char *intel_pt_find_overlap(unsigned char *buf_a, size_t len_a,
2627				     unsigned char *buf_b, size_t len_b,
2628				     bool have_tsc, bool *consecutive)
 
2629{
2630	unsigned char *found;
2631
2632	/* Buffer 'b' must start at PSB so throw away everything before that */
2633	if (!intel_pt_next_psb(&buf_b, &len_b))
2634		return buf_b + len_b; /* No PSB */
2635
2636	if (!intel_pt_next_psb(&buf_a, &len_a))
2637		return buf_b; /* No overlap */
2638
2639	if (have_tsc) {
2640		found = intel_pt_find_overlap_tsc(buf_a, len_a, buf_b, len_b,
2641						  consecutive);
2642		if (found)
2643			return found;
2644	}
2645
2646	/*
2647	 * Buffer 'b' cannot end within buffer 'a' so, for comparison purposes,
2648	 * we can ignore the first part of buffer 'a'.
2649	 */
2650	while (len_b < len_a) {
2651		if (!intel_pt_step_psb(&buf_a, &len_a))
2652			return buf_b; /* No overlap */
2653	}
2654
2655	/* Now len_b >= len_a */
2656	while (1) {
2657		/* Potential overlap so check the bytes */
2658		found = memmem(buf_a, len_a, buf_b, len_a);
2659		if (found) {
2660			*consecutive = true;
2661			return buf_b + len_a;
2662		}
2663
2664		/* Try again at next PSB in buffer 'a' */
2665		if (!intel_pt_step_psb(&buf_a, &len_a))
2666			return buf_b; /* No overlap */
2667	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2668}
v6.8
   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}