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v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * bpf-loader.c
   4 *
   5 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
   6 * Copyright (C) 2015 Huawei Inc.
   7 */
   8
   9#include <linux/bpf.h>
  10#include <bpf/libbpf.h>
  11#include <bpf/bpf.h>
  12#include <linux/err.h>
  13#include <linux/kernel.h>
  14#include <linux/string.h>
  15#include <linux/zalloc.h>
  16#include <errno.h>
  17#include <stdlib.h>
  18#include "debug.h"
  19#include "evlist.h"
  20#include "bpf-loader.h"
  21#include "bpf-prologue.h"
  22#include "probe-event.h"
  23#include "probe-finder.h" // for MAX_PROBES
  24#include "parse-events.h"
  25#include "strfilter.h"
  26#include "util.h"
  27#include "llvm-utils.h"
  28#include "c++/clang-c.h"
  29
  30#include <internal/xyarray.h>
  31
  32static int libbpf_perf_print(enum libbpf_print_level level __attribute__((unused)),
  33			      const char *fmt, va_list args)
  34{
  35	return veprintf(1, verbose, pr_fmt(fmt), args);
 
 
 
 
  36}
  37
 
 
 
 
  38struct bpf_prog_priv {
  39	bool is_tp;
  40	char *sys_name;
  41	char *evt_name;
  42	struct perf_probe_event pev;
  43	bool need_prologue;
  44	struct bpf_insn *insns_buf;
  45	int nr_types;
  46	int *type_mapping;
  47};
  48
  49static bool libbpf_initialized;
  50
  51struct bpf_object *
  52bpf__prepare_load_buffer(void *obj_buf, size_t obj_buf_sz, const char *name)
  53{
  54	struct bpf_object *obj;
  55
  56	if (!libbpf_initialized) {
  57		libbpf_set_print(libbpf_perf_print);
 
 
  58		libbpf_initialized = true;
  59	}
  60
  61	obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, name);
  62	if (IS_ERR_OR_NULL(obj)) {
  63		pr_debug("bpf: failed to load buffer\n");
  64		return ERR_PTR(-EINVAL);
  65	}
  66
  67	return obj;
  68}
  69
  70struct bpf_object *bpf__prepare_load(const char *filename, bool source)
  71{
  72	struct bpf_object *obj;
  73
  74	if (!libbpf_initialized) {
  75		libbpf_set_print(libbpf_perf_print);
 
 
  76		libbpf_initialized = true;
  77	}
  78
  79	if (source) {
  80		int err;
  81		void *obj_buf;
  82		size_t obj_buf_sz;
  83
  84		perf_clang__init();
  85		err = perf_clang__compile_bpf(filename, &obj_buf, &obj_buf_sz);
  86		perf_clang__cleanup();
  87		if (err) {
  88			pr_debug("bpf: builtin compilation failed: %d, try external compiler\n", err);
  89			err = llvm__compile_bpf(filename, &obj_buf, &obj_buf_sz);
  90			if (err)
  91				return ERR_PTR(-BPF_LOADER_ERRNO__COMPILE);
  92		} else
  93			pr_debug("bpf: successful builtin compilation\n");
  94		obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, filename);
  95
  96		if (!IS_ERR_OR_NULL(obj) && llvm_param.dump_obj)
  97			llvm__dump_obj(filename, obj_buf, obj_buf_sz);
  98
  99		free(obj_buf);
 100	} else
 101		obj = bpf_object__open(filename);
 102
 103	if (IS_ERR_OR_NULL(obj)) {
 104		pr_debug("bpf: failed to load %s\n", filename);
 105		return obj;
 106	}
 107
 108	return obj;
 109}
 110
 111void bpf__clear(void)
 112{
 113	struct bpf_object *obj, *tmp;
 114
 115	bpf_object__for_each_safe(obj, tmp) {
 116		bpf__unprobe(obj);
 117		bpf_object__close(obj);
 118	}
 119}
 120
 121static void
 122clear_prog_priv(struct bpf_program *prog __maybe_unused,
 123		void *_priv)
 124{
 125	struct bpf_prog_priv *priv = _priv;
 126
 127	cleanup_perf_probe_events(&priv->pev, 1);
 128	zfree(&priv->insns_buf);
 129	zfree(&priv->type_mapping);
 130	zfree(&priv->sys_name);
 131	zfree(&priv->evt_name);
 132	free(priv);
 133}
 134
 135static int
 136prog_config__exec(const char *value, struct perf_probe_event *pev)
 137{
 138	pev->uprobes = true;
 139	pev->target = strdup(value);
 140	if (!pev->target)
 141		return -ENOMEM;
 142	return 0;
 143}
 144
 145static int
 146prog_config__module(const char *value, struct perf_probe_event *pev)
 147{
 148	pev->uprobes = false;
 149	pev->target = strdup(value);
 150	if (!pev->target)
 151		return -ENOMEM;
 152	return 0;
 153}
 154
 155static int
 156prog_config__bool(const char *value, bool *pbool, bool invert)
 157{
 158	int err;
 159	bool bool_value;
 160
 161	if (!pbool)
 162		return -EINVAL;
 163
 164	err = strtobool(value, &bool_value);
 165	if (err)
 166		return err;
 167
 168	*pbool = invert ? !bool_value : bool_value;
 169	return 0;
 170}
 171
 172static int
 173prog_config__inlines(const char *value,
 174		     struct perf_probe_event *pev __maybe_unused)
 175{
 176	return prog_config__bool(value, &probe_conf.no_inlines, true);
 177}
 178
 179static int
 180prog_config__force(const char *value,
 181		   struct perf_probe_event *pev __maybe_unused)
 182{
 183	return prog_config__bool(value, &probe_conf.force_add, false);
 184}
 185
 186static struct {
 187	const char *key;
 188	const char *usage;
 189	const char *desc;
 190	int (*func)(const char *, struct perf_probe_event *);
 191} bpf_prog_config_terms[] = {
 192	{
 193		.key	= "exec",
 194		.usage	= "exec=<full path of file>",
 195		.desc	= "Set uprobe target",
 196		.func	= prog_config__exec,
 197	},
 198	{
 199		.key	= "module",
 200		.usage	= "module=<module name>    ",
 201		.desc	= "Set kprobe module",
 202		.func	= prog_config__module,
 203	},
 204	{
 205		.key	= "inlines",
 206		.usage	= "inlines=[yes|no]        ",
 207		.desc	= "Probe at inline symbol",
 208		.func	= prog_config__inlines,
 209	},
 210	{
 211		.key	= "force",
 212		.usage	= "force=[yes|no]          ",
 213		.desc	= "Forcibly add events with existing name",
 214		.func	= prog_config__force,
 215	},
 216};
 217
 218static int
 219do_prog_config(const char *key, const char *value,
 220	       struct perf_probe_event *pev)
 221{
 222	unsigned int i;
 223
 224	pr_debug("config bpf program: %s=%s\n", key, value);
 225	for (i = 0; i < ARRAY_SIZE(bpf_prog_config_terms); i++)
 226		if (strcmp(key, bpf_prog_config_terms[i].key) == 0)
 227			return bpf_prog_config_terms[i].func(value, pev);
 228
 229	pr_debug("BPF: ERROR: invalid program config option: %s=%s\n",
 230		 key, value);
 231
 232	pr_debug("\nHint: Valid options are:\n");
 233	for (i = 0; i < ARRAY_SIZE(bpf_prog_config_terms); i++)
 234		pr_debug("\t%s:\t%s\n", bpf_prog_config_terms[i].usage,
 235			 bpf_prog_config_terms[i].desc);
 236	pr_debug("\n");
 237
 238	return -BPF_LOADER_ERRNO__PROGCONF_TERM;
 239}
 240
 241static const char *
 242parse_prog_config_kvpair(const char *config_str, struct perf_probe_event *pev)
 243{
 244	char *text = strdup(config_str);
 245	char *sep, *line;
 246	const char *main_str = NULL;
 247	int err = 0;
 248
 249	if (!text) {
 250		pr_debug("Not enough memory: dup config_str failed\n");
 251		return ERR_PTR(-ENOMEM);
 252	}
 253
 254	line = text;
 255	while ((sep = strchr(line, ';'))) {
 256		char *equ;
 257
 258		*sep = '\0';
 259		equ = strchr(line, '=');
 260		if (!equ) {
 261			pr_warning("WARNING: invalid config in BPF object: %s\n",
 262				   line);
 263			pr_warning("\tShould be 'key=value'.\n");
 264			goto nextline;
 265		}
 266		*equ = '\0';
 267
 268		err = do_prog_config(line, equ + 1, pev);
 269		if (err)
 270			break;
 271nextline:
 272		line = sep + 1;
 273	}
 274
 275	if (!err)
 276		main_str = config_str + (line - text);
 277	free(text);
 278
 279	return err ? ERR_PTR(err) : main_str;
 280}
 281
 282static int
 283parse_prog_config(const char *config_str, const char **p_main_str,
 284		  bool *is_tp, struct perf_probe_event *pev)
 285{
 286	int err;
 287	const char *main_str = parse_prog_config_kvpair(config_str, pev);
 288
 289	if (IS_ERR(main_str))
 290		return PTR_ERR(main_str);
 291
 292	*p_main_str = main_str;
 293	if (!strchr(main_str, '=')) {
 294		/* Is a tracepoint event? */
 295		const char *s = strchr(main_str, ':');
 296
 297		if (!s) {
 298			pr_debug("bpf: '%s' is not a valid tracepoint\n",
 299				 config_str);
 300			return -BPF_LOADER_ERRNO__CONFIG;
 301		}
 302
 303		*is_tp = true;
 304		return 0;
 305	}
 306
 307	*is_tp = false;
 308	err = parse_perf_probe_command(main_str, pev);
 309	if (err < 0) {
 310		pr_debug("bpf: '%s' is not a valid config string\n",
 311			 config_str);
 312		/* parse failed, don't need clear pev. */
 313		return -BPF_LOADER_ERRNO__CONFIG;
 314	}
 315	return 0;
 316}
 317
 318static int
 319config_bpf_program(struct bpf_program *prog)
 320{
 321	struct perf_probe_event *pev = NULL;
 322	struct bpf_prog_priv *priv = NULL;
 323	const char *config_str, *main_str;
 324	bool is_tp = false;
 325	int err;
 326
 327	/* Initialize per-program probing setting */
 328	probe_conf.no_inlines = false;
 329	probe_conf.force_add = false;
 330
 331	config_str = bpf_program__title(prog, false);
 332	if (IS_ERR(config_str)) {
 333		pr_debug("bpf: unable to get title for program\n");
 334		return PTR_ERR(config_str);
 335	}
 336
 337	priv = calloc(sizeof(*priv), 1);
 338	if (!priv) {
 339		pr_debug("bpf: failed to alloc priv\n");
 340		return -ENOMEM;
 341	}
 342	pev = &priv->pev;
 343
 344	pr_debug("bpf: config program '%s'\n", config_str);
 345	err = parse_prog_config(config_str, &main_str, &is_tp, pev);
 346	if (err)
 347		goto errout;
 348
 349	if (is_tp) {
 350		char *s = strchr(main_str, ':');
 351
 352		priv->is_tp = true;
 353		priv->sys_name = strndup(main_str, s - main_str);
 354		priv->evt_name = strdup(s + 1);
 355		goto set_priv;
 356	}
 357
 358	if (pev->group && strcmp(pev->group, PERF_BPF_PROBE_GROUP)) {
 359		pr_debug("bpf: '%s': group for event is set and not '%s'.\n",
 360			 config_str, PERF_BPF_PROBE_GROUP);
 361		err = -BPF_LOADER_ERRNO__GROUP;
 362		goto errout;
 363	} else if (!pev->group)
 364		pev->group = strdup(PERF_BPF_PROBE_GROUP);
 365
 366	if (!pev->group) {
 367		pr_debug("bpf: strdup failed\n");
 368		err = -ENOMEM;
 369		goto errout;
 370	}
 371
 372	if (!pev->event) {
 373		pr_debug("bpf: '%s': event name is missing. Section name should be 'key=value'\n",
 374			 config_str);
 375		err = -BPF_LOADER_ERRNO__EVENTNAME;
 376		goto errout;
 377	}
 378	pr_debug("bpf: config '%s' is ok\n", config_str);
 379
 380set_priv:
 381	err = bpf_program__set_priv(prog, priv, clear_prog_priv);
 382	if (err) {
 383		pr_debug("Failed to set priv for program '%s'\n", config_str);
 384		goto errout;
 385	}
 386
 387	return 0;
 388
 389errout:
 390	if (pev)
 391		clear_perf_probe_event(pev);
 392	free(priv);
 393	return err;
 394}
 395
 396static int bpf__prepare_probe(void)
 397{
 398	static int err = 0;
 399	static bool initialized = false;
 400
 401	/*
 402	 * Make err static, so if init failed the first, bpf__prepare_probe()
 403	 * fails each time without calling init_probe_symbol_maps multiple
 404	 * times.
 405	 */
 406	if (initialized)
 407		return err;
 408
 409	initialized = true;
 410	err = init_probe_symbol_maps(false);
 411	if (err < 0)
 412		pr_debug("Failed to init_probe_symbol_maps\n");
 413	probe_conf.max_probes = MAX_PROBES;
 414	return err;
 415}
 416
 417static int
 418preproc_gen_prologue(struct bpf_program *prog, int n,
 419		     struct bpf_insn *orig_insns, int orig_insns_cnt,
 420		     struct bpf_prog_prep_result *res)
 421{
 422	struct bpf_prog_priv *priv = bpf_program__priv(prog);
 423	struct probe_trace_event *tev;
 424	struct perf_probe_event *pev;
 425	struct bpf_insn *buf;
 426	size_t prologue_cnt = 0;
 427	int i, err;
 428
 429	if (IS_ERR(priv) || !priv || priv->is_tp)
 430		goto errout;
 431
 432	pev = &priv->pev;
 433
 434	if (n < 0 || n >= priv->nr_types)
 435		goto errout;
 436
 437	/* Find a tev belongs to that type */
 438	for (i = 0; i < pev->ntevs; i++) {
 439		if (priv->type_mapping[i] == n)
 440			break;
 441	}
 442
 443	if (i >= pev->ntevs) {
 444		pr_debug("Internal error: prologue type %d not found\n", n);
 445		return -BPF_LOADER_ERRNO__PROLOGUE;
 446	}
 447
 448	tev = &pev->tevs[i];
 449
 450	buf = priv->insns_buf;
 451	err = bpf__gen_prologue(tev->args, tev->nargs,
 452				buf, &prologue_cnt,
 453				BPF_MAXINSNS - orig_insns_cnt);
 454	if (err) {
 455		const char *title;
 456
 457		title = bpf_program__title(prog, false);
 458		if (!title)
 459			title = "[unknown]";
 460
 461		pr_debug("Failed to generate prologue for program %s\n",
 462			 title);
 463		return err;
 464	}
 465
 466	memcpy(&buf[prologue_cnt], orig_insns,
 467	       sizeof(struct bpf_insn) * orig_insns_cnt);
 468
 469	res->new_insn_ptr = buf;
 470	res->new_insn_cnt = prologue_cnt + orig_insns_cnt;
 471	res->pfd = NULL;
 472	return 0;
 473
 474errout:
 475	pr_debug("Internal error in preproc_gen_prologue\n");
 476	return -BPF_LOADER_ERRNO__PROLOGUE;
 477}
 478
 479/*
 480 * compare_tev_args is reflexive, transitive and antisymmetric.
 481 * I can proof it but this margin is too narrow to contain.
 482 */
 483static int compare_tev_args(const void *ptev1, const void *ptev2)
 484{
 485	int i, ret;
 486	const struct probe_trace_event *tev1 =
 487		*(const struct probe_trace_event **)ptev1;
 488	const struct probe_trace_event *tev2 =
 489		*(const struct probe_trace_event **)ptev2;
 490
 491	ret = tev2->nargs - tev1->nargs;
 492	if (ret)
 493		return ret;
 494
 495	for (i = 0; i < tev1->nargs; i++) {
 496		struct probe_trace_arg *arg1, *arg2;
 497		struct probe_trace_arg_ref *ref1, *ref2;
 498
 499		arg1 = &tev1->args[i];
 500		arg2 = &tev2->args[i];
 501
 502		ret = strcmp(arg1->value, arg2->value);
 503		if (ret)
 504			return ret;
 505
 506		ref1 = arg1->ref;
 507		ref2 = arg2->ref;
 508
 509		while (ref1 && ref2) {
 510			ret = ref2->offset - ref1->offset;
 511			if (ret)
 512				return ret;
 513
 514			ref1 = ref1->next;
 515			ref2 = ref2->next;
 516		}
 517
 518		if (ref1 || ref2)
 519			return ref2 ? 1 : -1;
 520	}
 521
 522	return 0;
 523}
 524
 525/*
 526 * Assign a type number to each tevs in a pev.
 527 * mapping is an array with same slots as tevs in that pev.
 528 * nr_types will be set to number of types.
 529 */
 530static int map_prologue(struct perf_probe_event *pev, int *mapping,
 531			int *nr_types)
 532{
 533	int i, type = 0;
 534	struct probe_trace_event **ptevs;
 535
 536	size_t array_sz = sizeof(*ptevs) * pev->ntevs;
 537
 538	ptevs = malloc(array_sz);
 539	if (!ptevs) {
 540		pr_debug("Not enough memory: alloc ptevs failed\n");
 541		return -ENOMEM;
 542	}
 543
 544	pr_debug("In map_prologue, ntevs=%d\n", pev->ntevs);
 545	for (i = 0; i < pev->ntevs; i++)
 546		ptevs[i] = &pev->tevs[i];
 547
 548	qsort(ptevs, pev->ntevs, sizeof(*ptevs),
 549	      compare_tev_args);
 550
 551	for (i = 0; i < pev->ntevs; i++) {
 552		int n;
 553
 554		n = ptevs[i] - pev->tevs;
 555		if (i == 0) {
 556			mapping[n] = type;
 557			pr_debug("mapping[%d]=%d\n", n, type);
 558			continue;
 559		}
 560
 561		if (compare_tev_args(ptevs + i, ptevs + i - 1) == 0)
 562			mapping[n] = type;
 563		else
 564			mapping[n] = ++type;
 565
 566		pr_debug("mapping[%d]=%d\n", n, mapping[n]);
 567	}
 568	free(ptevs);
 569	*nr_types = type + 1;
 570
 571	return 0;
 572}
 573
 574static int hook_load_preprocessor(struct bpf_program *prog)
 575{
 576	struct bpf_prog_priv *priv = bpf_program__priv(prog);
 577	struct perf_probe_event *pev;
 578	bool need_prologue = false;
 579	int err, i;
 580
 581	if (IS_ERR(priv) || !priv) {
 582		pr_debug("Internal error when hook preprocessor\n");
 583		return -BPF_LOADER_ERRNO__INTERNAL;
 584	}
 585
 586	if (priv->is_tp) {
 587		priv->need_prologue = false;
 588		return 0;
 589	}
 590
 591	pev = &priv->pev;
 592	for (i = 0; i < pev->ntevs; i++) {
 593		struct probe_trace_event *tev = &pev->tevs[i];
 594
 595		if (tev->nargs > 0) {
 596			need_prologue = true;
 597			break;
 598		}
 599	}
 600
 601	/*
 602	 * Since all tevs don't have argument, we don't need generate
 603	 * prologue.
 604	 */
 605	if (!need_prologue) {
 606		priv->need_prologue = false;
 607		return 0;
 608	}
 609
 610	priv->need_prologue = true;
 611	priv->insns_buf = malloc(sizeof(struct bpf_insn) * BPF_MAXINSNS);
 612	if (!priv->insns_buf) {
 613		pr_debug("Not enough memory: alloc insns_buf failed\n");
 614		return -ENOMEM;
 615	}
 616
 617	priv->type_mapping = malloc(sizeof(int) * pev->ntevs);
 618	if (!priv->type_mapping) {
 619		pr_debug("Not enough memory: alloc type_mapping failed\n");
 620		return -ENOMEM;
 621	}
 622	memset(priv->type_mapping, -1,
 623	       sizeof(int) * pev->ntevs);
 624
 625	err = map_prologue(pev, priv->type_mapping, &priv->nr_types);
 626	if (err)
 627		return err;
 628
 629	err = bpf_program__set_prep(prog, priv->nr_types,
 630				    preproc_gen_prologue);
 631	return err;
 632}
 633
 634int bpf__probe(struct bpf_object *obj)
 635{
 636	int err = 0;
 637	struct bpf_program *prog;
 638	struct bpf_prog_priv *priv;
 639	struct perf_probe_event *pev;
 640
 641	err = bpf__prepare_probe();
 642	if (err) {
 643		pr_debug("bpf__prepare_probe failed\n");
 644		return err;
 645	}
 646
 647	bpf_object__for_each_program(prog, obj) {
 648		err = config_bpf_program(prog);
 649		if (err)
 650			goto out;
 651
 652		priv = bpf_program__priv(prog);
 653		if (IS_ERR(priv) || !priv) {
 654			err = PTR_ERR(priv);
 655			goto out;
 656		}
 657
 658		if (priv->is_tp) {
 659			bpf_program__set_tracepoint(prog);
 660			continue;
 661		}
 662
 663		bpf_program__set_kprobe(prog);
 664		pev = &priv->pev;
 665
 666		err = convert_perf_probe_events(pev, 1);
 667		if (err < 0) {
 668			pr_debug("bpf_probe: failed to convert perf probe events\n");
 669			goto out;
 670		}
 671
 672		err = apply_perf_probe_events(pev, 1);
 673		if (err < 0) {
 674			pr_debug("bpf_probe: failed to apply perf probe events\n");
 675			goto out;
 676		}
 677
 678		/*
 679		 * After probing, let's consider prologue, which
 680		 * adds program fetcher to BPF programs.
 681		 *
 682		 * hook_load_preprocessorr() hooks pre-processor
 683		 * to bpf_program, let it generate prologue
 684		 * dynamically during loading.
 685		 */
 686		err = hook_load_preprocessor(prog);
 687		if (err)
 688			goto out;
 689	}
 690out:
 691	return err < 0 ? err : 0;
 692}
 693
 694#define EVENTS_WRITE_BUFSIZE  4096
 695int bpf__unprobe(struct bpf_object *obj)
 696{
 697	int err, ret = 0;
 698	struct bpf_program *prog;
 699
 700	bpf_object__for_each_program(prog, obj) {
 701		struct bpf_prog_priv *priv = bpf_program__priv(prog);
 702		int i;
 703
 704		if (IS_ERR(priv) || !priv || priv->is_tp)
 705			continue;
 706
 707		for (i = 0; i < priv->pev.ntevs; i++) {
 708			struct probe_trace_event *tev = &priv->pev.tevs[i];
 709			char name_buf[EVENTS_WRITE_BUFSIZE];
 710			struct strfilter *delfilter;
 711
 712			snprintf(name_buf, EVENTS_WRITE_BUFSIZE,
 713				 "%s:%s", tev->group, tev->event);
 714			name_buf[EVENTS_WRITE_BUFSIZE - 1] = '\0';
 715
 716			delfilter = strfilter__new(name_buf, NULL);
 717			if (!delfilter) {
 718				pr_debug("Failed to create filter for unprobing\n");
 719				ret = -ENOMEM;
 720				continue;
 721			}
 722
 723			err = del_perf_probe_events(delfilter);
 724			strfilter__delete(delfilter);
 725			if (err) {
 726				pr_debug("Failed to delete %s\n", name_buf);
 727				ret = err;
 728				continue;
 729			}
 730		}
 731	}
 732	return ret;
 733}
 734
 735int bpf__load(struct bpf_object *obj)
 736{
 737	int err;
 738
 739	err = bpf_object__load(obj);
 740	if (err) {
 741		char bf[128];
 742		libbpf_strerror(err, bf, sizeof(bf));
 743		pr_debug("bpf: load objects failed: err=%d: (%s)\n", err, bf);
 744		return err;
 745	}
 746	return 0;
 747}
 748
 749int bpf__foreach_event(struct bpf_object *obj,
 750		       bpf_prog_iter_callback_t func,
 751		       void *arg)
 752{
 753	struct bpf_program *prog;
 754	int err;
 755
 756	bpf_object__for_each_program(prog, obj) {
 757		struct bpf_prog_priv *priv = bpf_program__priv(prog);
 758		struct probe_trace_event *tev;
 759		struct perf_probe_event *pev;
 760		int i, fd;
 761
 762		if (IS_ERR(priv) || !priv) {
 763			pr_debug("bpf: failed to get private field\n");
 764			return -BPF_LOADER_ERRNO__INTERNAL;
 765		}
 766
 767		if (priv->is_tp) {
 768			fd = bpf_program__fd(prog);
 769			err = (*func)(priv->sys_name, priv->evt_name, fd, obj, arg);
 770			if (err) {
 771				pr_debug("bpf: tracepoint call back failed, stop iterate\n");
 772				return err;
 773			}
 774			continue;
 775		}
 776
 777		pev = &priv->pev;
 778		for (i = 0; i < pev->ntevs; i++) {
 779			tev = &pev->tevs[i];
 780
 781			if (priv->need_prologue) {
 782				int type = priv->type_mapping[i];
 783
 784				fd = bpf_program__nth_fd(prog, type);
 785			} else {
 786				fd = bpf_program__fd(prog);
 787			}
 788
 789			if (fd < 0) {
 790				pr_debug("bpf: failed to get file descriptor\n");
 791				return fd;
 792			}
 793
 794			err = (*func)(tev->group, tev->event, fd, obj, arg);
 795			if (err) {
 796				pr_debug("bpf: call back failed, stop iterate\n");
 797				return err;
 798			}
 799		}
 800	}
 801	return 0;
 802}
 803
 804enum bpf_map_op_type {
 805	BPF_MAP_OP_SET_VALUE,
 806	BPF_MAP_OP_SET_EVSEL,
 807};
 808
 809enum bpf_map_key_type {
 810	BPF_MAP_KEY_ALL,
 811	BPF_MAP_KEY_RANGES,
 812};
 813
 814struct bpf_map_op {
 815	struct list_head list;
 816	enum bpf_map_op_type op_type;
 817	enum bpf_map_key_type key_type;
 818	union {
 819		struct parse_events_array array;
 820	} k;
 821	union {
 822		u64 value;
 823		struct evsel *evsel;
 824	} v;
 825};
 826
 827struct bpf_map_priv {
 828	struct list_head ops_list;
 829};
 830
 831static void
 832bpf_map_op__delete(struct bpf_map_op *op)
 833{
 834	if (!list_empty(&op->list))
 835		list_del_init(&op->list);
 836	if (op->key_type == BPF_MAP_KEY_RANGES)
 837		parse_events__clear_array(&op->k.array);
 838	free(op);
 839}
 840
 841static void
 842bpf_map_priv__purge(struct bpf_map_priv *priv)
 843{
 844	struct bpf_map_op *pos, *n;
 845
 846	list_for_each_entry_safe(pos, n, &priv->ops_list, list) {
 847		list_del_init(&pos->list);
 848		bpf_map_op__delete(pos);
 849	}
 850}
 851
 852static void
 853bpf_map_priv__clear(struct bpf_map *map __maybe_unused,
 854		    void *_priv)
 855{
 856	struct bpf_map_priv *priv = _priv;
 857
 858	bpf_map_priv__purge(priv);
 859	free(priv);
 860}
 861
 862static int
 863bpf_map_op_setkey(struct bpf_map_op *op, struct parse_events_term *term)
 864{
 865	op->key_type = BPF_MAP_KEY_ALL;
 866	if (!term)
 867		return 0;
 868
 869	if (term->array.nr_ranges) {
 870		size_t memsz = term->array.nr_ranges *
 871				sizeof(op->k.array.ranges[0]);
 872
 873		op->k.array.ranges = memdup(term->array.ranges, memsz);
 874		if (!op->k.array.ranges) {
 875			pr_debug("Not enough memory to alloc indices for map\n");
 876			return -ENOMEM;
 877		}
 878		op->key_type = BPF_MAP_KEY_RANGES;
 879		op->k.array.nr_ranges = term->array.nr_ranges;
 880	}
 881	return 0;
 882}
 883
 884static struct bpf_map_op *
 885bpf_map_op__new(struct parse_events_term *term)
 886{
 887	struct bpf_map_op *op;
 888	int err;
 889
 890	op = zalloc(sizeof(*op));
 891	if (!op) {
 892		pr_debug("Failed to alloc bpf_map_op\n");
 893		return ERR_PTR(-ENOMEM);
 894	}
 895	INIT_LIST_HEAD(&op->list);
 896
 897	err = bpf_map_op_setkey(op, term);
 898	if (err) {
 899		free(op);
 900		return ERR_PTR(err);
 901	}
 902	return op;
 903}
 904
 905static struct bpf_map_op *
 906bpf_map_op__clone(struct bpf_map_op *op)
 907{
 908	struct bpf_map_op *newop;
 909
 910	newop = memdup(op, sizeof(*op));
 911	if (!newop) {
 912		pr_debug("Failed to alloc bpf_map_op\n");
 913		return NULL;
 914	}
 915
 916	INIT_LIST_HEAD(&newop->list);
 917	if (op->key_type == BPF_MAP_KEY_RANGES) {
 918		size_t memsz = op->k.array.nr_ranges *
 919			       sizeof(op->k.array.ranges[0]);
 920
 921		newop->k.array.ranges = memdup(op->k.array.ranges, memsz);
 922		if (!newop->k.array.ranges) {
 923			pr_debug("Failed to alloc indices for map\n");
 924			free(newop);
 925			return NULL;
 926		}
 927	}
 928
 929	return newop;
 930}
 931
 932static struct bpf_map_priv *
 933bpf_map_priv__clone(struct bpf_map_priv *priv)
 934{
 935	struct bpf_map_priv *newpriv;
 936	struct bpf_map_op *pos, *newop;
 937
 938	newpriv = zalloc(sizeof(*newpriv));
 939	if (!newpriv) {
 940		pr_debug("Not enough memory to alloc map private\n");
 941		return NULL;
 942	}
 943	INIT_LIST_HEAD(&newpriv->ops_list);
 944
 945	list_for_each_entry(pos, &priv->ops_list, list) {
 946		newop = bpf_map_op__clone(pos);
 947		if (!newop) {
 948			bpf_map_priv__purge(newpriv);
 949			return NULL;
 950		}
 951		list_add_tail(&newop->list, &newpriv->ops_list);
 952	}
 953
 954	return newpriv;
 955}
 956
 957static int
 958bpf_map__add_op(struct bpf_map *map, struct bpf_map_op *op)
 959{
 960	const char *map_name = bpf_map__name(map);
 961	struct bpf_map_priv *priv = bpf_map__priv(map);
 962
 963	if (IS_ERR(priv)) {
 964		pr_debug("Failed to get private from map %s\n", map_name);
 965		return PTR_ERR(priv);
 966	}
 967
 968	if (!priv) {
 969		priv = zalloc(sizeof(*priv));
 970		if (!priv) {
 971			pr_debug("Not enough memory to alloc map private\n");
 972			return -ENOMEM;
 973		}
 974		INIT_LIST_HEAD(&priv->ops_list);
 975
 976		if (bpf_map__set_priv(map, priv, bpf_map_priv__clear)) {
 977			free(priv);
 978			return -BPF_LOADER_ERRNO__INTERNAL;
 979		}
 980	}
 981
 982	list_add_tail(&op->list, &priv->ops_list);
 983	return 0;
 984}
 985
 986static struct bpf_map_op *
 987bpf_map__add_newop(struct bpf_map *map, struct parse_events_term *term)
 988{
 989	struct bpf_map_op *op;
 990	int err;
 991
 992	op = bpf_map_op__new(term);
 993	if (IS_ERR(op))
 994		return op;
 995
 996	err = bpf_map__add_op(map, op);
 997	if (err) {
 998		bpf_map_op__delete(op);
 999		return ERR_PTR(err);
1000	}
1001	return op;
1002}
1003
1004static int
1005__bpf_map__config_value(struct bpf_map *map,
1006			struct parse_events_term *term)
1007{
1008	struct bpf_map_op *op;
1009	const char *map_name = bpf_map__name(map);
1010	const struct bpf_map_def *def = bpf_map__def(map);
1011
1012	if (IS_ERR(def)) {
1013		pr_debug("Unable to get map definition from '%s'\n",
1014			 map_name);
1015		return -BPF_LOADER_ERRNO__INTERNAL;
1016	}
1017
1018	if (def->type != BPF_MAP_TYPE_ARRAY) {
1019		pr_debug("Map %s type is not BPF_MAP_TYPE_ARRAY\n",
1020			 map_name);
1021		return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1022	}
1023	if (def->key_size < sizeof(unsigned int)) {
1024		pr_debug("Map %s has incorrect key size\n", map_name);
1025		return -BPF_LOADER_ERRNO__OBJCONF_MAP_KEYSIZE;
1026	}
1027	switch (def->value_size) {
1028	case 1:
1029	case 2:
1030	case 4:
1031	case 8:
1032		break;
1033	default:
1034		pr_debug("Map %s has incorrect value size\n", map_name);
1035		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE;
1036	}
1037
1038	op = bpf_map__add_newop(map, term);
1039	if (IS_ERR(op))
1040		return PTR_ERR(op);
1041	op->op_type = BPF_MAP_OP_SET_VALUE;
1042	op->v.value = term->val.num;
1043	return 0;
1044}
1045
1046static int
1047bpf_map__config_value(struct bpf_map *map,
1048		      struct parse_events_term *term,
1049		      struct evlist *evlist __maybe_unused)
1050{
1051	if (!term->err_val) {
1052		pr_debug("Config value not set\n");
1053		return -BPF_LOADER_ERRNO__OBJCONF_CONF;
1054	}
1055
1056	if (term->type_val != PARSE_EVENTS__TERM_TYPE_NUM) {
1057		pr_debug("ERROR: wrong value type for 'value'\n");
1058		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE;
1059	}
1060
1061	return __bpf_map__config_value(map, term);
1062}
1063
1064static int
1065__bpf_map__config_event(struct bpf_map *map,
1066			struct parse_events_term *term,
1067			struct evlist *evlist)
1068{
1069	struct evsel *evsel;
1070	const struct bpf_map_def *def;
1071	struct bpf_map_op *op;
1072	const char *map_name = bpf_map__name(map);
1073
1074	evsel = perf_evlist__find_evsel_by_str(evlist, term->val.str);
1075	if (!evsel) {
1076		pr_debug("Event (for '%s') '%s' doesn't exist\n",
1077			 map_name, term->val.str);
1078		return -BPF_LOADER_ERRNO__OBJCONF_MAP_NOEVT;
1079	}
1080
1081	def = bpf_map__def(map);
1082	if (IS_ERR(def)) {
1083		pr_debug("Unable to get map definition from '%s'\n",
1084			 map_name);
1085		return PTR_ERR(def);
1086	}
1087
1088	/*
1089	 * No need to check key_size and value_size:
1090	 * kernel has already checked them.
1091	 */
1092	if (def->type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
1093		pr_debug("Map %s type is not BPF_MAP_TYPE_PERF_EVENT_ARRAY\n",
1094			 map_name);
1095		return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1096	}
1097
1098	op = bpf_map__add_newop(map, term);
1099	if (IS_ERR(op))
1100		return PTR_ERR(op);
1101	op->op_type = BPF_MAP_OP_SET_EVSEL;
1102	op->v.evsel = evsel;
1103	return 0;
1104}
1105
1106static int
1107bpf_map__config_event(struct bpf_map *map,
1108		      struct parse_events_term *term,
1109		      struct evlist *evlist)
1110{
1111	if (!term->err_val) {
1112		pr_debug("Config value not set\n");
1113		return -BPF_LOADER_ERRNO__OBJCONF_CONF;
1114	}
1115
1116	if (term->type_val != PARSE_EVENTS__TERM_TYPE_STR) {
1117		pr_debug("ERROR: wrong value type for 'event'\n");
1118		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE;
1119	}
1120
1121	return __bpf_map__config_event(map, term, evlist);
1122}
1123
1124struct bpf_obj_config__map_func {
1125	const char *config_opt;
1126	int (*config_func)(struct bpf_map *, struct parse_events_term *,
1127			   struct evlist *);
1128};
1129
1130struct bpf_obj_config__map_func bpf_obj_config__map_funcs[] = {
1131	{"value", bpf_map__config_value},
1132	{"event", bpf_map__config_event},
1133};
1134
1135static int
1136config_map_indices_range_check(struct parse_events_term *term,
1137			       struct bpf_map *map,
1138			       const char *map_name)
1139{
1140	struct parse_events_array *array = &term->array;
1141	const struct bpf_map_def *def;
1142	unsigned int i;
1143
1144	if (!array->nr_ranges)
1145		return 0;
1146	if (!array->ranges) {
1147		pr_debug("ERROR: map %s: array->nr_ranges is %d but range array is NULL\n",
1148			 map_name, (int)array->nr_ranges);
1149		return -BPF_LOADER_ERRNO__INTERNAL;
1150	}
1151
1152	def = bpf_map__def(map);
1153	if (IS_ERR(def)) {
1154		pr_debug("ERROR: Unable to get map definition from '%s'\n",
1155			 map_name);
1156		return -BPF_LOADER_ERRNO__INTERNAL;
1157	}
1158
1159	for (i = 0; i < array->nr_ranges; i++) {
1160		unsigned int start = array->ranges[i].start;
1161		size_t length = array->ranges[i].length;
1162		unsigned int idx = start + length - 1;
1163
1164		if (idx >= def->max_entries) {
1165			pr_debug("ERROR: index %d too large\n", idx);
1166			return -BPF_LOADER_ERRNO__OBJCONF_MAP_IDX2BIG;
1167		}
1168	}
1169	return 0;
1170}
1171
1172static int
1173bpf__obj_config_map(struct bpf_object *obj,
1174		    struct parse_events_term *term,
1175		    struct evlist *evlist,
1176		    int *key_scan_pos)
1177{
1178	/* key is "map:<mapname>.<config opt>" */
1179	char *map_name = strdup(term->config + sizeof("map:") - 1);
1180	struct bpf_map *map;
1181	int err = -BPF_LOADER_ERRNO__OBJCONF_OPT;
1182	char *map_opt;
1183	size_t i;
1184
1185	if (!map_name)
1186		return -ENOMEM;
1187
1188	map_opt = strchr(map_name, '.');
1189	if (!map_opt) {
1190		pr_debug("ERROR: Invalid map config: %s\n", map_name);
1191		goto out;
1192	}
1193
1194	*map_opt++ = '\0';
1195	if (*map_opt == '\0') {
1196		pr_debug("ERROR: Invalid map option: %s\n", term->config);
1197		goto out;
1198	}
1199
1200	map = bpf_object__find_map_by_name(obj, map_name);
1201	if (!map) {
1202		pr_debug("ERROR: Map %s doesn't exist\n", map_name);
1203		err = -BPF_LOADER_ERRNO__OBJCONF_MAP_NOTEXIST;
1204		goto out;
1205	}
1206
1207	*key_scan_pos += strlen(map_opt);
1208	err = config_map_indices_range_check(term, map, map_name);
1209	if (err)
1210		goto out;
1211	*key_scan_pos -= strlen(map_opt);
1212
1213	for (i = 0; i < ARRAY_SIZE(bpf_obj_config__map_funcs); i++) {
1214		struct bpf_obj_config__map_func *func =
1215				&bpf_obj_config__map_funcs[i];
1216
1217		if (strcmp(map_opt, func->config_opt) == 0) {
1218			err = func->config_func(map, term, evlist);
1219			goto out;
1220		}
1221	}
1222
1223	pr_debug("ERROR: Invalid map config option '%s'\n", map_opt);
1224	err = -BPF_LOADER_ERRNO__OBJCONF_MAP_OPT;
1225out:
1226	free(map_name);
1227	if (!err)
1228		key_scan_pos += strlen(map_opt);
1229	return err;
1230}
1231
1232int bpf__config_obj(struct bpf_object *obj,
1233		    struct parse_events_term *term,
1234		    struct evlist *evlist,
1235		    int *error_pos)
1236{
1237	int key_scan_pos = 0;
1238	int err;
1239
1240	if (!obj || !term || !term->config)
1241		return -EINVAL;
1242
1243	if (strstarts(term->config, "map:")) {
1244		key_scan_pos = sizeof("map:") - 1;
1245		err = bpf__obj_config_map(obj, term, evlist, &key_scan_pos);
1246		goto out;
1247	}
1248	err = -BPF_LOADER_ERRNO__OBJCONF_OPT;
1249out:
1250	if (error_pos)
1251		*error_pos = key_scan_pos;
1252	return err;
1253
1254}
1255
1256typedef int (*map_config_func_t)(const char *name, int map_fd,
1257				 const struct bpf_map_def *pdef,
1258				 struct bpf_map_op *op,
1259				 void *pkey, void *arg);
1260
1261static int
1262foreach_key_array_all(map_config_func_t func,
1263		      void *arg, const char *name,
1264		      int map_fd, const struct bpf_map_def *pdef,
1265		      struct bpf_map_op *op)
1266{
1267	unsigned int i;
1268	int err;
1269
1270	for (i = 0; i < pdef->max_entries; i++) {
1271		err = func(name, map_fd, pdef, op, &i, arg);
1272		if (err) {
1273			pr_debug("ERROR: failed to insert value to %s[%u]\n",
1274				 name, i);
1275			return err;
1276		}
1277	}
1278	return 0;
1279}
1280
1281static int
1282foreach_key_array_ranges(map_config_func_t func, void *arg,
1283			 const char *name, int map_fd,
1284			 const struct bpf_map_def *pdef,
1285			 struct bpf_map_op *op)
1286{
1287	unsigned int i, j;
1288	int err;
1289
1290	for (i = 0; i < op->k.array.nr_ranges; i++) {
1291		unsigned int start = op->k.array.ranges[i].start;
1292		size_t length = op->k.array.ranges[i].length;
1293
1294		for (j = 0; j < length; j++) {
1295			unsigned int idx = start + j;
1296
1297			err = func(name, map_fd, pdef, op, &idx, arg);
1298			if (err) {
1299				pr_debug("ERROR: failed to insert value to %s[%u]\n",
1300					 name, idx);
1301				return err;
1302			}
1303		}
1304	}
1305	return 0;
1306}
1307
1308static int
1309bpf_map_config_foreach_key(struct bpf_map *map,
1310			   map_config_func_t func,
1311			   void *arg)
1312{
1313	int err, map_fd;
1314	struct bpf_map_op *op;
1315	const struct bpf_map_def *def;
1316	const char *name = bpf_map__name(map);
1317	struct bpf_map_priv *priv = bpf_map__priv(map);
1318
1319	if (IS_ERR(priv)) {
1320		pr_debug("ERROR: failed to get private from map %s\n", name);
1321		return -BPF_LOADER_ERRNO__INTERNAL;
1322	}
1323	if (!priv || list_empty(&priv->ops_list)) {
1324		pr_debug("INFO: nothing to config for map %s\n", name);
1325		return 0;
1326	}
1327
1328	def = bpf_map__def(map);
1329	if (IS_ERR(def)) {
1330		pr_debug("ERROR: failed to get definition from map %s\n", name);
1331		return -BPF_LOADER_ERRNO__INTERNAL;
1332	}
1333	map_fd = bpf_map__fd(map);
1334	if (map_fd < 0) {
1335		pr_debug("ERROR: failed to get fd from map %s\n", name);
1336		return map_fd;
1337	}
1338
1339	list_for_each_entry(op, &priv->ops_list, list) {
1340		switch (def->type) {
1341		case BPF_MAP_TYPE_ARRAY:
1342		case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
1343			switch (op->key_type) {
1344			case BPF_MAP_KEY_ALL:
1345				err = foreach_key_array_all(func, arg, name,
1346							    map_fd, def, op);
1347				break;
1348			case BPF_MAP_KEY_RANGES:
1349				err = foreach_key_array_ranges(func, arg, name,
1350							       map_fd, def,
1351							       op);
1352				break;
1353			default:
1354				pr_debug("ERROR: keytype for map '%s' invalid\n",
1355					 name);
1356				return -BPF_LOADER_ERRNO__INTERNAL;
1357			}
1358			if (err)
1359				return err;
1360			break;
1361		default:
1362			pr_debug("ERROR: type of '%s' incorrect\n", name);
1363			return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1364		}
1365	}
1366
1367	return 0;
1368}
1369
1370static int
1371apply_config_value_for_key(int map_fd, void *pkey,
1372			   size_t val_size, u64 val)
1373{
1374	int err = 0;
1375
1376	switch (val_size) {
1377	case 1: {
1378		u8 _val = (u8)(val);
1379		err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1380		break;
1381	}
1382	case 2: {
1383		u16 _val = (u16)(val);
1384		err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1385		break;
1386	}
1387	case 4: {
1388		u32 _val = (u32)(val);
1389		err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1390		break;
1391	}
1392	case 8: {
1393		err = bpf_map_update_elem(map_fd, pkey, &val, BPF_ANY);
1394		break;
1395	}
1396	default:
1397		pr_debug("ERROR: invalid value size\n");
1398		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE;
1399	}
1400	if (err && errno)
1401		err = -errno;
1402	return err;
1403}
1404
1405static int
1406apply_config_evsel_for_key(const char *name, int map_fd, void *pkey,
1407			   struct evsel *evsel)
1408{
1409	struct xyarray *xy = evsel->core.fd;
1410	struct perf_event_attr *attr;
1411	unsigned int key, events;
1412	bool check_pass = false;
1413	int *evt_fd;
1414	int err;
1415
1416	if (!xy) {
1417		pr_debug("ERROR: evsel not ready for map %s\n", name);
1418		return -BPF_LOADER_ERRNO__INTERNAL;
1419	}
1420
1421	if (xy->row_size / xy->entry_size != 1) {
1422		pr_debug("ERROR: Dimension of target event is incorrect for map %s\n",
1423			 name);
1424		return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM;
1425	}
1426
1427	attr = &evsel->core.attr;
1428	if (attr->inherit) {
1429		pr_debug("ERROR: Can't put inherit event into map %s\n", name);
1430		return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH;
1431	}
1432
1433	if (perf_evsel__is_bpf_output(evsel))
1434		check_pass = true;
1435	if (attr->type == PERF_TYPE_RAW)
1436		check_pass = true;
1437	if (attr->type == PERF_TYPE_HARDWARE)
1438		check_pass = true;
1439	if (!check_pass) {
1440		pr_debug("ERROR: Event type is wrong for map %s\n", name);
1441		return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE;
1442	}
1443
1444	events = xy->entries / (xy->row_size / xy->entry_size);
1445	key = *((unsigned int *)pkey);
1446	if (key >= events) {
1447		pr_debug("ERROR: there is no event %d for map %s\n",
1448			 key, name);
1449		return -BPF_LOADER_ERRNO__OBJCONF_MAP_MAPSIZE;
1450	}
1451	evt_fd = xyarray__entry(xy, key, 0);
1452	err = bpf_map_update_elem(map_fd, pkey, evt_fd, BPF_ANY);
1453	if (err && errno)
1454		err = -errno;
1455	return err;
1456}
1457
1458static int
1459apply_obj_config_map_for_key(const char *name, int map_fd,
1460			     const struct bpf_map_def *pdef,
1461			     struct bpf_map_op *op,
1462			     void *pkey, void *arg __maybe_unused)
1463{
1464	int err;
1465
1466	switch (op->op_type) {
1467	case BPF_MAP_OP_SET_VALUE:
1468		err = apply_config_value_for_key(map_fd, pkey,
1469						 pdef->value_size,
1470						 op->v.value);
1471		break;
1472	case BPF_MAP_OP_SET_EVSEL:
1473		err = apply_config_evsel_for_key(name, map_fd, pkey,
1474						 op->v.evsel);
1475		break;
1476	default:
1477		pr_debug("ERROR: unknown value type for '%s'\n", name);
1478		err = -BPF_LOADER_ERRNO__INTERNAL;
1479	}
1480	return err;
1481}
1482
1483static int
1484apply_obj_config_map(struct bpf_map *map)
1485{
1486	return bpf_map_config_foreach_key(map,
1487					  apply_obj_config_map_for_key,
1488					  NULL);
1489}
1490
1491static int
1492apply_obj_config_object(struct bpf_object *obj)
1493{
1494	struct bpf_map *map;
1495	int err;
1496
1497	bpf_object__for_each_map(map, obj) {
1498		err = apply_obj_config_map(map);
1499		if (err)
1500			return err;
1501	}
1502	return 0;
1503}
1504
1505int bpf__apply_obj_config(void)
1506{
1507	struct bpf_object *obj, *tmp;
1508	int err;
1509
1510	bpf_object__for_each_safe(obj, tmp) {
1511		err = apply_obj_config_object(obj);
1512		if (err)
1513			return err;
1514	}
1515
1516	return 0;
1517}
1518
1519#define bpf__for_each_map(pos, obj, objtmp)	\
1520	bpf_object__for_each_safe(obj, objtmp)	\
1521		bpf_object__for_each_map(pos, obj)
1522
1523#define bpf__for_each_map_named(pos, obj, objtmp, name)	\
1524	bpf__for_each_map(pos, obj, objtmp) 		\
1525		if (bpf_map__name(pos) && 		\
1526			(strcmp(name, 			\
1527				bpf_map__name(pos)) == 0))
1528
1529struct evsel *bpf__setup_output_event(struct evlist *evlist, const char *name)
1530{
1531	struct bpf_map_priv *tmpl_priv = NULL;
1532	struct bpf_object *obj, *tmp;
1533	struct evsel *evsel = NULL;
1534	struct bpf_map *map;
1535	int err;
1536	bool need_init = false;
1537
1538	bpf__for_each_map_named(map, obj, tmp, name) {
1539		struct bpf_map_priv *priv = bpf_map__priv(map);
1540
1541		if (IS_ERR(priv))
1542			return ERR_PTR(-BPF_LOADER_ERRNO__INTERNAL);
1543
1544		/*
1545		 * No need to check map type: type should have been
1546		 * verified by kernel.
1547		 */
1548		if (!need_init && !priv)
1549			need_init = !priv;
1550		if (!tmpl_priv && priv)
1551			tmpl_priv = priv;
1552	}
1553
1554	if (!need_init)
1555		return NULL;
1556
1557	if (!tmpl_priv) {
1558		char *event_definition = NULL;
1559
1560		if (asprintf(&event_definition, "bpf-output/no-inherit=1,name=%s/", name) < 0)
1561			return ERR_PTR(-ENOMEM);
1562
1563		err = parse_events(evlist, event_definition, NULL);
1564		free(event_definition);
1565
1566		if (err) {
1567			pr_debug("ERROR: failed to create the \"%s\" bpf-output event\n", name);
1568			return ERR_PTR(-err);
1569		}
1570
1571		evsel = evlist__last(evlist);
1572	}
1573
1574	bpf__for_each_map_named(map, obj, tmp, name) {
1575		struct bpf_map_priv *priv = bpf_map__priv(map);
1576
1577		if (IS_ERR(priv))
1578			return ERR_PTR(-BPF_LOADER_ERRNO__INTERNAL);
1579		if (priv)
1580			continue;
1581
1582		if (tmpl_priv) {
1583			priv = bpf_map_priv__clone(tmpl_priv);
1584			if (!priv)
1585				return ERR_PTR(-ENOMEM);
1586
1587			err = bpf_map__set_priv(map, priv, bpf_map_priv__clear);
1588			if (err) {
1589				bpf_map_priv__clear(map, priv);
1590				return ERR_PTR(err);
1591			}
1592		} else if (evsel) {
1593			struct bpf_map_op *op;
1594
1595			op = bpf_map__add_newop(map, NULL);
1596			if (IS_ERR(op))
1597				return ERR_CAST(op);
1598			op->op_type = BPF_MAP_OP_SET_EVSEL;
1599			op->v.evsel = evsel;
1600		}
1601	}
1602
1603	return evsel;
1604}
1605
1606int bpf__setup_stdout(struct evlist *evlist)
1607{
1608	struct evsel *evsel = bpf__setup_output_event(evlist, "__bpf_stdout__");
1609	return PTR_ERR_OR_ZERO(evsel);
1610}
1611
1612#define ERRNO_OFFSET(e)		((e) - __BPF_LOADER_ERRNO__START)
1613#define ERRCODE_OFFSET(c)	ERRNO_OFFSET(BPF_LOADER_ERRNO__##c)
1614#define NR_ERRNO	(__BPF_LOADER_ERRNO__END - __BPF_LOADER_ERRNO__START)
1615
1616static const char *bpf_loader_strerror_table[NR_ERRNO] = {
1617	[ERRCODE_OFFSET(CONFIG)]	= "Invalid config string",
1618	[ERRCODE_OFFSET(GROUP)]		= "Invalid group name",
1619	[ERRCODE_OFFSET(EVENTNAME)]	= "No event name found in config string",
1620	[ERRCODE_OFFSET(INTERNAL)]	= "BPF loader internal error",
1621	[ERRCODE_OFFSET(COMPILE)]	= "Error when compiling BPF scriptlet",
1622	[ERRCODE_OFFSET(PROGCONF_TERM)]	= "Invalid program config term in config string",
1623	[ERRCODE_OFFSET(PROLOGUE)]	= "Failed to generate prologue",
1624	[ERRCODE_OFFSET(PROLOGUE2BIG)]	= "Prologue too big for program",
1625	[ERRCODE_OFFSET(PROLOGUEOOB)]	= "Offset out of bound for prologue",
1626	[ERRCODE_OFFSET(OBJCONF_OPT)]	= "Invalid object config option",
1627	[ERRCODE_OFFSET(OBJCONF_CONF)]	= "Config value not set (missing '=')",
1628	[ERRCODE_OFFSET(OBJCONF_MAP_OPT)]	= "Invalid object map config option",
1629	[ERRCODE_OFFSET(OBJCONF_MAP_NOTEXIST)]	= "Target map doesn't exist",
1630	[ERRCODE_OFFSET(OBJCONF_MAP_VALUE)]	= "Incorrect value type for map",
1631	[ERRCODE_OFFSET(OBJCONF_MAP_TYPE)]	= "Incorrect map type",
1632	[ERRCODE_OFFSET(OBJCONF_MAP_KEYSIZE)]	= "Incorrect map key size",
1633	[ERRCODE_OFFSET(OBJCONF_MAP_VALUESIZE)]	= "Incorrect map value size",
1634	[ERRCODE_OFFSET(OBJCONF_MAP_NOEVT)]	= "Event not found for map setting",
1635	[ERRCODE_OFFSET(OBJCONF_MAP_MAPSIZE)]	= "Invalid map size for event setting",
1636	[ERRCODE_OFFSET(OBJCONF_MAP_EVTDIM)]	= "Event dimension too large",
1637	[ERRCODE_OFFSET(OBJCONF_MAP_EVTINH)]	= "Doesn't support inherit event",
1638	[ERRCODE_OFFSET(OBJCONF_MAP_EVTTYPE)]	= "Wrong event type for map",
1639	[ERRCODE_OFFSET(OBJCONF_MAP_IDX2BIG)]	= "Index too large",
1640};
1641
1642static int
1643bpf_loader_strerror(int err, char *buf, size_t size)
1644{
1645	char sbuf[STRERR_BUFSIZE];
1646	const char *msg;
1647
1648	if (!buf || !size)
1649		return -1;
1650
1651	err = err > 0 ? err : -err;
1652
1653	if (err >= __LIBBPF_ERRNO__START)
1654		return libbpf_strerror(err, buf, size);
1655
1656	if (err >= __BPF_LOADER_ERRNO__START && err < __BPF_LOADER_ERRNO__END) {
1657		msg = bpf_loader_strerror_table[ERRNO_OFFSET(err)];
1658		snprintf(buf, size, "%s", msg);
1659		buf[size - 1] = '\0';
1660		return 0;
1661	}
1662
1663	if (err >= __BPF_LOADER_ERRNO__END)
1664		snprintf(buf, size, "Unknown bpf loader error %d", err);
1665	else
1666		snprintf(buf, size, "%s",
1667			 str_error_r(err, sbuf, sizeof(sbuf)));
1668
1669	buf[size - 1] = '\0';
1670	return -1;
1671}
1672
1673#define bpf__strerror_head(err, buf, size) \
1674	char sbuf[STRERR_BUFSIZE], *emsg;\
1675	if (!size)\
1676		return 0;\
1677	if (err < 0)\
1678		err = -err;\
1679	bpf_loader_strerror(err, sbuf, sizeof(sbuf));\
1680	emsg = sbuf;\
1681	switch (err) {\
1682	default:\
1683		scnprintf(buf, size, "%s", emsg);\
1684		break;
1685
1686#define bpf__strerror_entry(val, fmt...)\
1687	case val: {\
1688		scnprintf(buf, size, fmt);\
1689		break;\
1690	}
1691
1692#define bpf__strerror_end(buf, size)\
1693	}\
1694	buf[size - 1] = '\0';
1695
1696int bpf__strerror_prepare_load(const char *filename, bool source,
1697			       int err, char *buf, size_t size)
1698{
1699	size_t n;
1700	int ret;
1701
1702	n = snprintf(buf, size, "Failed to load %s%s: ",
1703			 filename, source ? " from source" : "");
1704	if (n >= size) {
1705		buf[size - 1] = '\0';
1706		return 0;
1707	}
1708	buf += n;
1709	size -= n;
1710
1711	ret = bpf_loader_strerror(err, buf, size);
1712	buf[size - 1] = '\0';
1713	return ret;
1714}
1715
1716int bpf__strerror_probe(struct bpf_object *obj __maybe_unused,
1717			int err, char *buf, size_t size)
1718{
1719	bpf__strerror_head(err, buf, size);
1720	case BPF_LOADER_ERRNO__PROGCONF_TERM: {
1721		scnprintf(buf, size, "%s (add -v to see detail)", emsg);
1722		break;
1723	}
1724	bpf__strerror_entry(EEXIST, "Probe point exist. Try 'perf probe -d \"*\"' and set 'force=yes'");
1725	bpf__strerror_entry(EACCES, "You need to be root");
1726	bpf__strerror_entry(EPERM, "You need to be root, and /proc/sys/kernel/kptr_restrict should be 0");
1727	bpf__strerror_entry(ENOENT, "You need to check probing points in BPF file");
1728	bpf__strerror_end(buf, size);
1729	return 0;
1730}
1731
1732int bpf__strerror_load(struct bpf_object *obj,
1733		       int err, char *buf, size_t size)
1734{
1735	bpf__strerror_head(err, buf, size);
1736	case LIBBPF_ERRNO__KVER: {
1737		unsigned int obj_kver = bpf_object__kversion(obj);
1738		unsigned int real_kver;
1739
1740		if (fetch_kernel_version(&real_kver, NULL, 0)) {
1741			scnprintf(buf, size, "Unable to fetch kernel version");
1742			break;
1743		}
1744
1745		if (obj_kver != real_kver) {
1746			scnprintf(buf, size,
1747				  "'version' ("KVER_FMT") doesn't match running kernel ("KVER_FMT")",
1748				  KVER_PARAM(obj_kver),
1749				  KVER_PARAM(real_kver));
1750			break;
1751		}
1752
1753		scnprintf(buf, size, "Failed to load program for unknown reason");
1754		break;
1755	}
1756	bpf__strerror_end(buf, size);
1757	return 0;
1758}
1759
1760int bpf__strerror_config_obj(struct bpf_object *obj __maybe_unused,
1761			     struct parse_events_term *term __maybe_unused,
1762			     struct evlist *evlist __maybe_unused,
1763			     int *error_pos __maybe_unused, int err,
1764			     char *buf, size_t size)
1765{
1766	bpf__strerror_head(err, buf, size);
1767	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE,
1768			    "Can't use this config term with this map type");
1769	bpf__strerror_end(buf, size);
1770	return 0;
1771}
1772
1773int bpf__strerror_apply_obj_config(int err, char *buf, size_t size)
1774{
1775	bpf__strerror_head(err, buf, size);
1776	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM,
1777			    "Cannot set event to BPF map in multi-thread tracing");
1778	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH,
1779			    "%s (Hint: use -i to turn off inherit)", emsg);
1780	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE,
1781			    "Can only put raw, hardware and BPF output event into a BPF map");
1782	bpf__strerror_end(buf, size);
1783	return 0;
1784}
1785
1786int bpf__strerror_setup_output_event(struct evlist *evlist __maybe_unused,
1787				     int err, char *buf, size_t size)
1788{
1789	bpf__strerror_head(err, buf, size);
1790	bpf__strerror_end(buf, size);
1791	return 0;
1792}
v4.10.11
 
   1/*
   2 * bpf-loader.c
   3 *
   4 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
   5 * Copyright (C) 2015 Huawei Inc.
   6 */
   7
   8#include <linux/bpf.h>
   9#include <bpf/libbpf.h>
  10#include <bpf/bpf.h>
  11#include <linux/err.h>
 
  12#include <linux/string.h>
  13#include "perf.h"
 
 
  14#include "debug.h"
 
  15#include "bpf-loader.h"
  16#include "bpf-prologue.h"
  17#include "probe-event.h"
  18#include "probe-finder.h" // for MAX_PROBES
  19#include "parse-events.h"
 
 
  20#include "llvm-utils.h"
  21#include "c++/clang-c.h"
  22
  23#define DEFINE_PRINT_FN(name, level) \
  24static int libbpf_##name(const char *fmt, ...)	\
  25{						\
  26	va_list args;				\
  27	int ret;				\
  28						\
  29	va_start(args, fmt);			\
  30	ret = veprintf(level, verbose, pr_fmt(fmt), args);\
  31	va_end(args);				\
  32	return ret;				\
  33}
  34
  35DEFINE_PRINT_FN(warning, 1)
  36DEFINE_PRINT_FN(info, 1)
  37DEFINE_PRINT_FN(debug, 1)
  38
  39struct bpf_prog_priv {
  40	bool is_tp;
  41	char *sys_name;
  42	char *evt_name;
  43	struct perf_probe_event pev;
  44	bool need_prologue;
  45	struct bpf_insn *insns_buf;
  46	int nr_types;
  47	int *type_mapping;
  48};
  49
  50static bool libbpf_initialized;
  51
  52struct bpf_object *
  53bpf__prepare_load_buffer(void *obj_buf, size_t obj_buf_sz, const char *name)
  54{
  55	struct bpf_object *obj;
  56
  57	if (!libbpf_initialized) {
  58		libbpf_set_print(libbpf_warning,
  59				 libbpf_info,
  60				 libbpf_debug);
  61		libbpf_initialized = true;
  62	}
  63
  64	obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, name);
  65	if (IS_ERR(obj)) {
  66		pr_debug("bpf: failed to load buffer\n");
  67		return ERR_PTR(-EINVAL);
  68	}
  69
  70	return obj;
  71}
  72
  73struct bpf_object *bpf__prepare_load(const char *filename, bool source)
  74{
  75	struct bpf_object *obj;
  76
  77	if (!libbpf_initialized) {
  78		libbpf_set_print(libbpf_warning,
  79				 libbpf_info,
  80				 libbpf_debug);
  81		libbpf_initialized = true;
  82	}
  83
  84	if (source) {
  85		int err;
  86		void *obj_buf;
  87		size_t obj_buf_sz;
  88
  89		perf_clang__init();
  90		err = perf_clang__compile_bpf(filename, &obj_buf, &obj_buf_sz);
  91		perf_clang__cleanup();
  92		if (err) {
  93			pr_warning("bpf: builtin compilation failed: %d, try external compiler\n", err);
  94			err = llvm__compile_bpf(filename, &obj_buf, &obj_buf_sz);
  95			if (err)
  96				return ERR_PTR(-BPF_LOADER_ERRNO__COMPILE);
  97		} else
  98			pr_debug("bpf: successfull builtin compilation\n");
  99		obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, filename);
 100
 101		if (!IS_ERR(obj) && llvm_param.dump_obj)
 102			llvm__dump_obj(filename, obj_buf, obj_buf_sz);
 103
 104		free(obj_buf);
 105	} else
 106		obj = bpf_object__open(filename);
 107
 108	if (IS_ERR(obj)) {
 109		pr_debug("bpf: failed to load %s\n", filename);
 110		return obj;
 111	}
 112
 113	return obj;
 114}
 115
 116void bpf__clear(void)
 117{
 118	struct bpf_object *obj, *tmp;
 119
 120	bpf_object__for_each_safe(obj, tmp) {
 121		bpf__unprobe(obj);
 122		bpf_object__close(obj);
 123	}
 124}
 125
 126static void
 127clear_prog_priv(struct bpf_program *prog __maybe_unused,
 128		void *_priv)
 129{
 130	struct bpf_prog_priv *priv = _priv;
 131
 132	cleanup_perf_probe_events(&priv->pev, 1);
 133	zfree(&priv->insns_buf);
 134	zfree(&priv->type_mapping);
 135	zfree(&priv->sys_name);
 136	zfree(&priv->evt_name);
 137	free(priv);
 138}
 139
 140static int
 141prog_config__exec(const char *value, struct perf_probe_event *pev)
 142{
 143	pev->uprobes = true;
 144	pev->target = strdup(value);
 145	if (!pev->target)
 146		return -ENOMEM;
 147	return 0;
 148}
 149
 150static int
 151prog_config__module(const char *value, struct perf_probe_event *pev)
 152{
 153	pev->uprobes = false;
 154	pev->target = strdup(value);
 155	if (!pev->target)
 156		return -ENOMEM;
 157	return 0;
 158}
 159
 160static int
 161prog_config__bool(const char *value, bool *pbool, bool invert)
 162{
 163	int err;
 164	bool bool_value;
 165
 166	if (!pbool)
 167		return -EINVAL;
 168
 169	err = strtobool(value, &bool_value);
 170	if (err)
 171		return err;
 172
 173	*pbool = invert ? !bool_value : bool_value;
 174	return 0;
 175}
 176
 177static int
 178prog_config__inlines(const char *value,
 179		     struct perf_probe_event *pev __maybe_unused)
 180{
 181	return prog_config__bool(value, &probe_conf.no_inlines, true);
 182}
 183
 184static int
 185prog_config__force(const char *value,
 186		   struct perf_probe_event *pev __maybe_unused)
 187{
 188	return prog_config__bool(value, &probe_conf.force_add, false);
 189}
 190
 191static struct {
 192	const char *key;
 193	const char *usage;
 194	const char *desc;
 195	int (*func)(const char *, struct perf_probe_event *);
 196} bpf_prog_config_terms[] = {
 197	{
 198		.key	= "exec",
 199		.usage	= "exec=<full path of file>",
 200		.desc	= "Set uprobe target",
 201		.func	= prog_config__exec,
 202	},
 203	{
 204		.key	= "module",
 205		.usage	= "module=<module name>    ",
 206		.desc	= "Set kprobe module",
 207		.func	= prog_config__module,
 208	},
 209	{
 210		.key	= "inlines",
 211		.usage	= "inlines=[yes|no]        ",
 212		.desc	= "Probe at inline symbol",
 213		.func	= prog_config__inlines,
 214	},
 215	{
 216		.key	= "force",
 217		.usage	= "force=[yes|no]          ",
 218		.desc	= "Forcibly add events with existing name",
 219		.func	= prog_config__force,
 220	},
 221};
 222
 223static int
 224do_prog_config(const char *key, const char *value,
 225	       struct perf_probe_event *pev)
 226{
 227	unsigned int i;
 228
 229	pr_debug("config bpf program: %s=%s\n", key, value);
 230	for (i = 0; i < ARRAY_SIZE(bpf_prog_config_terms); i++)
 231		if (strcmp(key, bpf_prog_config_terms[i].key) == 0)
 232			return bpf_prog_config_terms[i].func(value, pev);
 233
 234	pr_debug("BPF: ERROR: invalid program config option: %s=%s\n",
 235		 key, value);
 236
 237	pr_debug("\nHint: Valid options are:\n");
 238	for (i = 0; i < ARRAY_SIZE(bpf_prog_config_terms); i++)
 239		pr_debug("\t%s:\t%s\n", bpf_prog_config_terms[i].usage,
 240			 bpf_prog_config_terms[i].desc);
 241	pr_debug("\n");
 242
 243	return -BPF_LOADER_ERRNO__PROGCONF_TERM;
 244}
 245
 246static const char *
 247parse_prog_config_kvpair(const char *config_str, struct perf_probe_event *pev)
 248{
 249	char *text = strdup(config_str);
 250	char *sep, *line;
 251	const char *main_str = NULL;
 252	int err = 0;
 253
 254	if (!text) {
 255		pr_debug("Not enough memory: dup config_str failed\n");
 256		return ERR_PTR(-ENOMEM);
 257	}
 258
 259	line = text;
 260	while ((sep = strchr(line, ';'))) {
 261		char *equ;
 262
 263		*sep = '\0';
 264		equ = strchr(line, '=');
 265		if (!equ) {
 266			pr_warning("WARNING: invalid config in BPF object: %s\n",
 267				   line);
 268			pr_warning("\tShould be 'key=value'.\n");
 269			goto nextline;
 270		}
 271		*equ = '\0';
 272
 273		err = do_prog_config(line, equ + 1, pev);
 274		if (err)
 275			break;
 276nextline:
 277		line = sep + 1;
 278	}
 279
 280	if (!err)
 281		main_str = config_str + (line - text);
 282	free(text);
 283
 284	return err ? ERR_PTR(err) : main_str;
 285}
 286
 287static int
 288parse_prog_config(const char *config_str, const char **p_main_str,
 289		  bool *is_tp, struct perf_probe_event *pev)
 290{
 291	int err;
 292	const char *main_str = parse_prog_config_kvpair(config_str, pev);
 293
 294	if (IS_ERR(main_str))
 295		return PTR_ERR(main_str);
 296
 297	*p_main_str = main_str;
 298	if (!strchr(main_str, '=')) {
 299		/* Is a tracepoint event? */
 300		const char *s = strchr(main_str, ':');
 301
 302		if (!s) {
 303			pr_debug("bpf: '%s' is not a valid tracepoint\n",
 304				 config_str);
 305			return -BPF_LOADER_ERRNO__CONFIG;
 306		}
 307
 308		*is_tp = true;
 309		return 0;
 310	}
 311
 312	*is_tp = false;
 313	err = parse_perf_probe_command(main_str, pev);
 314	if (err < 0) {
 315		pr_debug("bpf: '%s' is not a valid config string\n",
 316			 config_str);
 317		/* parse failed, don't need clear pev. */
 318		return -BPF_LOADER_ERRNO__CONFIG;
 319	}
 320	return 0;
 321}
 322
 323static int
 324config_bpf_program(struct bpf_program *prog)
 325{
 326	struct perf_probe_event *pev = NULL;
 327	struct bpf_prog_priv *priv = NULL;
 328	const char *config_str, *main_str;
 329	bool is_tp = false;
 330	int err;
 331
 332	/* Initialize per-program probing setting */
 333	probe_conf.no_inlines = false;
 334	probe_conf.force_add = false;
 335
 336	config_str = bpf_program__title(prog, false);
 337	if (IS_ERR(config_str)) {
 338		pr_debug("bpf: unable to get title for program\n");
 339		return PTR_ERR(config_str);
 340	}
 341
 342	priv = calloc(sizeof(*priv), 1);
 343	if (!priv) {
 344		pr_debug("bpf: failed to alloc priv\n");
 345		return -ENOMEM;
 346	}
 347	pev = &priv->pev;
 348
 349	pr_debug("bpf: config program '%s'\n", config_str);
 350	err = parse_prog_config(config_str, &main_str, &is_tp, pev);
 351	if (err)
 352		goto errout;
 353
 354	if (is_tp) {
 355		char *s = strchr(main_str, ':');
 356
 357		priv->is_tp = true;
 358		priv->sys_name = strndup(main_str, s - main_str);
 359		priv->evt_name = strdup(s + 1);
 360		goto set_priv;
 361	}
 362
 363	if (pev->group && strcmp(pev->group, PERF_BPF_PROBE_GROUP)) {
 364		pr_debug("bpf: '%s': group for event is set and not '%s'.\n",
 365			 config_str, PERF_BPF_PROBE_GROUP);
 366		err = -BPF_LOADER_ERRNO__GROUP;
 367		goto errout;
 368	} else if (!pev->group)
 369		pev->group = strdup(PERF_BPF_PROBE_GROUP);
 370
 371	if (!pev->group) {
 372		pr_debug("bpf: strdup failed\n");
 373		err = -ENOMEM;
 374		goto errout;
 375	}
 376
 377	if (!pev->event) {
 378		pr_debug("bpf: '%s': event name is missing. Section name should be 'key=value'\n",
 379			 config_str);
 380		err = -BPF_LOADER_ERRNO__EVENTNAME;
 381		goto errout;
 382	}
 383	pr_debug("bpf: config '%s' is ok\n", config_str);
 384
 385set_priv:
 386	err = bpf_program__set_priv(prog, priv, clear_prog_priv);
 387	if (err) {
 388		pr_debug("Failed to set priv for program '%s'\n", config_str);
 389		goto errout;
 390	}
 391
 392	return 0;
 393
 394errout:
 395	if (pev)
 396		clear_perf_probe_event(pev);
 397	free(priv);
 398	return err;
 399}
 400
 401static int bpf__prepare_probe(void)
 402{
 403	static int err = 0;
 404	static bool initialized = false;
 405
 406	/*
 407	 * Make err static, so if init failed the first, bpf__prepare_probe()
 408	 * fails each time without calling init_probe_symbol_maps multiple
 409	 * times.
 410	 */
 411	if (initialized)
 412		return err;
 413
 414	initialized = true;
 415	err = init_probe_symbol_maps(false);
 416	if (err < 0)
 417		pr_debug("Failed to init_probe_symbol_maps\n");
 418	probe_conf.max_probes = MAX_PROBES;
 419	return err;
 420}
 421
 422static int
 423preproc_gen_prologue(struct bpf_program *prog, int n,
 424		     struct bpf_insn *orig_insns, int orig_insns_cnt,
 425		     struct bpf_prog_prep_result *res)
 426{
 427	struct bpf_prog_priv *priv = bpf_program__priv(prog);
 428	struct probe_trace_event *tev;
 429	struct perf_probe_event *pev;
 430	struct bpf_insn *buf;
 431	size_t prologue_cnt = 0;
 432	int i, err;
 433
 434	if (IS_ERR(priv) || !priv || priv->is_tp)
 435		goto errout;
 436
 437	pev = &priv->pev;
 438
 439	if (n < 0 || n >= priv->nr_types)
 440		goto errout;
 441
 442	/* Find a tev belongs to that type */
 443	for (i = 0; i < pev->ntevs; i++) {
 444		if (priv->type_mapping[i] == n)
 445			break;
 446	}
 447
 448	if (i >= pev->ntevs) {
 449		pr_debug("Internal error: prologue type %d not found\n", n);
 450		return -BPF_LOADER_ERRNO__PROLOGUE;
 451	}
 452
 453	tev = &pev->tevs[i];
 454
 455	buf = priv->insns_buf;
 456	err = bpf__gen_prologue(tev->args, tev->nargs,
 457				buf, &prologue_cnt,
 458				BPF_MAXINSNS - orig_insns_cnt);
 459	if (err) {
 460		const char *title;
 461
 462		title = bpf_program__title(prog, false);
 463		if (!title)
 464			title = "[unknown]";
 465
 466		pr_debug("Failed to generate prologue for program %s\n",
 467			 title);
 468		return err;
 469	}
 470
 471	memcpy(&buf[prologue_cnt], orig_insns,
 472	       sizeof(struct bpf_insn) * orig_insns_cnt);
 473
 474	res->new_insn_ptr = buf;
 475	res->new_insn_cnt = prologue_cnt + orig_insns_cnt;
 476	res->pfd = NULL;
 477	return 0;
 478
 479errout:
 480	pr_debug("Internal error in preproc_gen_prologue\n");
 481	return -BPF_LOADER_ERRNO__PROLOGUE;
 482}
 483
 484/*
 485 * compare_tev_args is reflexive, transitive and antisymmetric.
 486 * I can proof it but this margin is too narrow to contain.
 487 */
 488static int compare_tev_args(const void *ptev1, const void *ptev2)
 489{
 490	int i, ret;
 491	const struct probe_trace_event *tev1 =
 492		*(const struct probe_trace_event **)ptev1;
 493	const struct probe_trace_event *tev2 =
 494		*(const struct probe_trace_event **)ptev2;
 495
 496	ret = tev2->nargs - tev1->nargs;
 497	if (ret)
 498		return ret;
 499
 500	for (i = 0; i < tev1->nargs; i++) {
 501		struct probe_trace_arg *arg1, *arg2;
 502		struct probe_trace_arg_ref *ref1, *ref2;
 503
 504		arg1 = &tev1->args[i];
 505		arg2 = &tev2->args[i];
 506
 507		ret = strcmp(arg1->value, arg2->value);
 508		if (ret)
 509			return ret;
 510
 511		ref1 = arg1->ref;
 512		ref2 = arg2->ref;
 513
 514		while (ref1 && ref2) {
 515			ret = ref2->offset - ref1->offset;
 516			if (ret)
 517				return ret;
 518
 519			ref1 = ref1->next;
 520			ref2 = ref2->next;
 521		}
 522
 523		if (ref1 || ref2)
 524			return ref2 ? 1 : -1;
 525	}
 526
 527	return 0;
 528}
 529
 530/*
 531 * Assign a type number to each tevs in a pev.
 532 * mapping is an array with same slots as tevs in that pev.
 533 * nr_types will be set to number of types.
 534 */
 535static int map_prologue(struct perf_probe_event *pev, int *mapping,
 536			int *nr_types)
 537{
 538	int i, type = 0;
 539	struct probe_trace_event **ptevs;
 540
 541	size_t array_sz = sizeof(*ptevs) * pev->ntevs;
 542
 543	ptevs = malloc(array_sz);
 544	if (!ptevs) {
 545		pr_debug("Not enough memory: alloc ptevs failed\n");
 546		return -ENOMEM;
 547	}
 548
 549	pr_debug("In map_prologue, ntevs=%d\n", pev->ntevs);
 550	for (i = 0; i < pev->ntevs; i++)
 551		ptevs[i] = &pev->tevs[i];
 552
 553	qsort(ptevs, pev->ntevs, sizeof(*ptevs),
 554	      compare_tev_args);
 555
 556	for (i = 0; i < pev->ntevs; i++) {
 557		int n;
 558
 559		n = ptevs[i] - pev->tevs;
 560		if (i == 0) {
 561			mapping[n] = type;
 562			pr_debug("mapping[%d]=%d\n", n, type);
 563			continue;
 564		}
 565
 566		if (compare_tev_args(ptevs + i, ptevs + i - 1) == 0)
 567			mapping[n] = type;
 568		else
 569			mapping[n] = ++type;
 570
 571		pr_debug("mapping[%d]=%d\n", n, mapping[n]);
 572	}
 573	free(ptevs);
 574	*nr_types = type + 1;
 575
 576	return 0;
 577}
 578
 579static int hook_load_preprocessor(struct bpf_program *prog)
 580{
 581	struct bpf_prog_priv *priv = bpf_program__priv(prog);
 582	struct perf_probe_event *pev;
 583	bool need_prologue = false;
 584	int err, i;
 585
 586	if (IS_ERR(priv) || !priv) {
 587		pr_debug("Internal error when hook preprocessor\n");
 588		return -BPF_LOADER_ERRNO__INTERNAL;
 589	}
 590
 591	if (priv->is_tp) {
 592		priv->need_prologue = false;
 593		return 0;
 594	}
 595
 596	pev = &priv->pev;
 597	for (i = 0; i < pev->ntevs; i++) {
 598		struct probe_trace_event *tev = &pev->tevs[i];
 599
 600		if (tev->nargs > 0) {
 601			need_prologue = true;
 602			break;
 603		}
 604	}
 605
 606	/*
 607	 * Since all tevs don't have argument, we don't need generate
 608	 * prologue.
 609	 */
 610	if (!need_prologue) {
 611		priv->need_prologue = false;
 612		return 0;
 613	}
 614
 615	priv->need_prologue = true;
 616	priv->insns_buf = malloc(sizeof(struct bpf_insn) * BPF_MAXINSNS);
 617	if (!priv->insns_buf) {
 618		pr_debug("Not enough memory: alloc insns_buf failed\n");
 619		return -ENOMEM;
 620	}
 621
 622	priv->type_mapping = malloc(sizeof(int) * pev->ntevs);
 623	if (!priv->type_mapping) {
 624		pr_debug("Not enough memory: alloc type_mapping failed\n");
 625		return -ENOMEM;
 626	}
 627	memset(priv->type_mapping, -1,
 628	       sizeof(int) * pev->ntevs);
 629
 630	err = map_prologue(pev, priv->type_mapping, &priv->nr_types);
 631	if (err)
 632		return err;
 633
 634	err = bpf_program__set_prep(prog, priv->nr_types,
 635				    preproc_gen_prologue);
 636	return err;
 637}
 638
 639int bpf__probe(struct bpf_object *obj)
 640{
 641	int err = 0;
 642	struct bpf_program *prog;
 643	struct bpf_prog_priv *priv;
 644	struct perf_probe_event *pev;
 645
 646	err = bpf__prepare_probe();
 647	if (err) {
 648		pr_debug("bpf__prepare_probe failed\n");
 649		return err;
 650	}
 651
 652	bpf_object__for_each_program(prog, obj) {
 653		err = config_bpf_program(prog);
 654		if (err)
 655			goto out;
 656
 657		priv = bpf_program__priv(prog);
 658		if (IS_ERR(priv) || !priv) {
 659			err = PTR_ERR(priv);
 660			goto out;
 661		}
 662
 663		if (priv->is_tp) {
 664			bpf_program__set_tracepoint(prog);
 665			continue;
 666		}
 667
 668		bpf_program__set_kprobe(prog);
 669		pev = &priv->pev;
 670
 671		err = convert_perf_probe_events(pev, 1);
 672		if (err < 0) {
 673			pr_debug("bpf_probe: failed to convert perf probe events");
 674			goto out;
 675		}
 676
 677		err = apply_perf_probe_events(pev, 1);
 678		if (err < 0) {
 679			pr_debug("bpf_probe: failed to apply perf probe events");
 680			goto out;
 681		}
 682
 683		/*
 684		 * After probing, let's consider prologue, which
 685		 * adds program fetcher to BPF programs.
 686		 *
 687		 * hook_load_preprocessorr() hooks pre-processor
 688		 * to bpf_program, let it generate prologue
 689		 * dynamically during loading.
 690		 */
 691		err = hook_load_preprocessor(prog);
 692		if (err)
 693			goto out;
 694	}
 695out:
 696	return err < 0 ? err : 0;
 697}
 698
 699#define EVENTS_WRITE_BUFSIZE  4096
 700int bpf__unprobe(struct bpf_object *obj)
 701{
 702	int err, ret = 0;
 703	struct bpf_program *prog;
 704
 705	bpf_object__for_each_program(prog, obj) {
 706		struct bpf_prog_priv *priv = bpf_program__priv(prog);
 707		int i;
 708
 709		if (IS_ERR(priv) || !priv || priv->is_tp)
 710			continue;
 711
 712		for (i = 0; i < priv->pev.ntevs; i++) {
 713			struct probe_trace_event *tev = &priv->pev.tevs[i];
 714			char name_buf[EVENTS_WRITE_BUFSIZE];
 715			struct strfilter *delfilter;
 716
 717			snprintf(name_buf, EVENTS_WRITE_BUFSIZE,
 718				 "%s:%s", tev->group, tev->event);
 719			name_buf[EVENTS_WRITE_BUFSIZE - 1] = '\0';
 720
 721			delfilter = strfilter__new(name_buf, NULL);
 722			if (!delfilter) {
 723				pr_debug("Failed to create filter for unprobing\n");
 724				ret = -ENOMEM;
 725				continue;
 726			}
 727
 728			err = del_perf_probe_events(delfilter);
 729			strfilter__delete(delfilter);
 730			if (err) {
 731				pr_debug("Failed to delete %s\n", name_buf);
 732				ret = err;
 733				continue;
 734			}
 735		}
 736	}
 737	return ret;
 738}
 739
 740int bpf__load(struct bpf_object *obj)
 741{
 742	int err;
 743
 744	err = bpf_object__load(obj);
 745	if (err) {
 746		pr_debug("bpf: load objects failed\n");
 
 
 747		return err;
 748	}
 749	return 0;
 750}
 751
 752int bpf__foreach_event(struct bpf_object *obj,
 753		       bpf_prog_iter_callback_t func,
 754		       void *arg)
 755{
 756	struct bpf_program *prog;
 757	int err;
 758
 759	bpf_object__for_each_program(prog, obj) {
 760		struct bpf_prog_priv *priv = bpf_program__priv(prog);
 761		struct probe_trace_event *tev;
 762		struct perf_probe_event *pev;
 763		int i, fd;
 764
 765		if (IS_ERR(priv) || !priv) {
 766			pr_debug("bpf: failed to get private field\n");
 767			return -BPF_LOADER_ERRNO__INTERNAL;
 768		}
 769
 770		if (priv->is_tp) {
 771			fd = bpf_program__fd(prog);
 772			err = (*func)(priv->sys_name, priv->evt_name, fd, arg);
 773			if (err) {
 774				pr_debug("bpf: tracepoint call back failed, stop iterate\n");
 775				return err;
 776			}
 777			continue;
 778		}
 779
 780		pev = &priv->pev;
 781		for (i = 0; i < pev->ntevs; i++) {
 782			tev = &pev->tevs[i];
 783
 784			if (priv->need_prologue) {
 785				int type = priv->type_mapping[i];
 786
 787				fd = bpf_program__nth_fd(prog, type);
 788			} else {
 789				fd = bpf_program__fd(prog);
 790			}
 791
 792			if (fd < 0) {
 793				pr_debug("bpf: failed to get file descriptor\n");
 794				return fd;
 795			}
 796
 797			err = (*func)(tev->group, tev->event, fd, arg);
 798			if (err) {
 799				pr_debug("bpf: call back failed, stop iterate\n");
 800				return err;
 801			}
 802		}
 803	}
 804	return 0;
 805}
 806
 807enum bpf_map_op_type {
 808	BPF_MAP_OP_SET_VALUE,
 809	BPF_MAP_OP_SET_EVSEL,
 810};
 811
 812enum bpf_map_key_type {
 813	BPF_MAP_KEY_ALL,
 814	BPF_MAP_KEY_RANGES,
 815};
 816
 817struct bpf_map_op {
 818	struct list_head list;
 819	enum bpf_map_op_type op_type;
 820	enum bpf_map_key_type key_type;
 821	union {
 822		struct parse_events_array array;
 823	} k;
 824	union {
 825		u64 value;
 826		struct perf_evsel *evsel;
 827	} v;
 828};
 829
 830struct bpf_map_priv {
 831	struct list_head ops_list;
 832};
 833
 834static void
 835bpf_map_op__delete(struct bpf_map_op *op)
 836{
 837	if (!list_empty(&op->list))
 838		list_del(&op->list);
 839	if (op->key_type == BPF_MAP_KEY_RANGES)
 840		parse_events__clear_array(&op->k.array);
 841	free(op);
 842}
 843
 844static void
 845bpf_map_priv__purge(struct bpf_map_priv *priv)
 846{
 847	struct bpf_map_op *pos, *n;
 848
 849	list_for_each_entry_safe(pos, n, &priv->ops_list, list) {
 850		list_del_init(&pos->list);
 851		bpf_map_op__delete(pos);
 852	}
 853}
 854
 855static void
 856bpf_map_priv__clear(struct bpf_map *map __maybe_unused,
 857		    void *_priv)
 858{
 859	struct bpf_map_priv *priv = _priv;
 860
 861	bpf_map_priv__purge(priv);
 862	free(priv);
 863}
 864
 865static int
 866bpf_map_op_setkey(struct bpf_map_op *op, struct parse_events_term *term)
 867{
 868	op->key_type = BPF_MAP_KEY_ALL;
 869	if (!term)
 870		return 0;
 871
 872	if (term->array.nr_ranges) {
 873		size_t memsz = term->array.nr_ranges *
 874				sizeof(op->k.array.ranges[0]);
 875
 876		op->k.array.ranges = memdup(term->array.ranges, memsz);
 877		if (!op->k.array.ranges) {
 878			pr_debug("Not enough memory to alloc indices for map\n");
 879			return -ENOMEM;
 880		}
 881		op->key_type = BPF_MAP_KEY_RANGES;
 882		op->k.array.nr_ranges = term->array.nr_ranges;
 883	}
 884	return 0;
 885}
 886
 887static struct bpf_map_op *
 888bpf_map_op__new(struct parse_events_term *term)
 889{
 890	struct bpf_map_op *op;
 891	int err;
 892
 893	op = zalloc(sizeof(*op));
 894	if (!op) {
 895		pr_debug("Failed to alloc bpf_map_op\n");
 896		return ERR_PTR(-ENOMEM);
 897	}
 898	INIT_LIST_HEAD(&op->list);
 899
 900	err = bpf_map_op_setkey(op, term);
 901	if (err) {
 902		free(op);
 903		return ERR_PTR(err);
 904	}
 905	return op;
 906}
 907
 908static struct bpf_map_op *
 909bpf_map_op__clone(struct bpf_map_op *op)
 910{
 911	struct bpf_map_op *newop;
 912
 913	newop = memdup(op, sizeof(*op));
 914	if (!newop) {
 915		pr_debug("Failed to alloc bpf_map_op\n");
 916		return NULL;
 917	}
 918
 919	INIT_LIST_HEAD(&newop->list);
 920	if (op->key_type == BPF_MAP_KEY_RANGES) {
 921		size_t memsz = op->k.array.nr_ranges *
 922			       sizeof(op->k.array.ranges[0]);
 923
 924		newop->k.array.ranges = memdup(op->k.array.ranges, memsz);
 925		if (!newop->k.array.ranges) {
 926			pr_debug("Failed to alloc indices for map\n");
 927			free(newop);
 928			return NULL;
 929		}
 930	}
 931
 932	return newop;
 933}
 934
 935static struct bpf_map_priv *
 936bpf_map_priv__clone(struct bpf_map_priv *priv)
 937{
 938	struct bpf_map_priv *newpriv;
 939	struct bpf_map_op *pos, *newop;
 940
 941	newpriv = zalloc(sizeof(*newpriv));
 942	if (!newpriv) {
 943		pr_debug("Not enough memory to alloc map private\n");
 944		return NULL;
 945	}
 946	INIT_LIST_HEAD(&newpriv->ops_list);
 947
 948	list_for_each_entry(pos, &priv->ops_list, list) {
 949		newop = bpf_map_op__clone(pos);
 950		if (!newop) {
 951			bpf_map_priv__purge(newpriv);
 952			return NULL;
 953		}
 954		list_add_tail(&newop->list, &newpriv->ops_list);
 955	}
 956
 957	return newpriv;
 958}
 959
 960static int
 961bpf_map__add_op(struct bpf_map *map, struct bpf_map_op *op)
 962{
 963	const char *map_name = bpf_map__name(map);
 964	struct bpf_map_priv *priv = bpf_map__priv(map);
 965
 966	if (IS_ERR(priv)) {
 967		pr_debug("Failed to get private from map %s\n", map_name);
 968		return PTR_ERR(priv);
 969	}
 970
 971	if (!priv) {
 972		priv = zalloc(sizeof(*priv));
 973		if (!priv) {
 974			pr_debug("Not enough memory to alloc map private\n");
 975			return -ENOMEM;
 976		}
 977		INIT_LIST_HEAD(&priv->ops_list);
 978
 979		if (bpf_map__set_priv(map, priv, bpf_map_priv__clear)) {
 980			free(priv);
 981			return -BPF_LOADER_ERRNO__INTERNAL;
 982		}
 983	}
 984
 985	list_add_tail(&op->list, &priv->ops_list);
 986	return 0;
 987}
 988
 989static struct bpf_map_op *
 990bpf_map__add_newop(struct bpf_map *map, struct parse_events_term *term)
 991{
 992	struct bpf_map_op *op;
 993	int err;
 994
 995	op = bpf_map_op__new(term);
 996	if (IS_ERR(op))
 997		return op;
 998
 999	err = bpf_map__add_op(map, op);
1000	if (err) {
1001		bpf_map_op__delete(op);
1002		return ERR_PTR(err);
1003	}
1004	return op;
1005}
1006
1007static int
1008__bpf_map__config_value(struct bpf_map *map,
1009			struct parse_events_term *term)
1010{
1011	struct bpf_map_op *op;
1012	const char *map_name = bpf_map__name(map);
1013	const struct bpf_map_def *def = bpf_map__def(map);
1014
1015	if (IS_ERR(def)) {
1016		pr_debug("Unable to get map definition from '%s'\n",
1017			 map_name);
1018		return -BPF_LOADER_ERRNO__INTERNAL;
1019	}
1020
1021	if (def->type != BPF_MAP_TYPE_ARRAY) {
1022		pr_debug("Map %s type is not BPF_MAP_TYPE_ARRAY\n",
1023			 map_name);
1024		return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1025	}
1026	if (def->key_size < sizeof(unsigned int)) {
1027		pr_debug("Map %s has incorrect key size\n", map_name);
1028		return -BPF_LOADER_ERRNO__OBJCONF_MAP_KEYSIZE;
1029	}
1030	switch (def->value_size) {
1031	case 1:
1032	case 2:
1033	case 4:
1034	case 8:
1035		break;
1036	default:
1037		pr_debug("Map %s has incorrect value size\n", map_name);
1038		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE;
1039	}
1040
1041	op = bpf_map__add_newop(map, term);
1042	if (IS_ERR(op))
1043		return PTR_ERR(op);
1044	op->op_type = BPF_MAP_OP_SET_VALUE;
1045	op->v.value = term->val.num;
1046	return 0;
1047}
1048
1049static int
1050bpf_map__config_value(struct bpf_map *map,
1051		      struct parse_events_term *term,
1052		      struct perf_evlist *evlist __maybe_unused)
1053{
1054	if (!term->err_val) {
1055		pr_debug("Config value not set\n");
1056		return -BPF_LOADER_ERRNO__OBJCONF_CONF;
1057	}
1058
1059	if (term->type_val != PARSE_EVENTS__TERM_TYPE_NUM) {
1060		pr_debug("ERROR: wrong value type for 'value'\n");
1061		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE;
1062	}
1063
1064	return __bpf_map__config_value(map, term);
1065}
1066
1067static int
1068__bpf_map__config_event(struct bpf_map *map,
1069			struct parse_events_term *term,
1070			struct perf_evlist *evlist)
1071{
1072	struct perf_evsel *evsel;
1073	const struct bpf_map_def *def;
1074	struct bpf_map_op *op;
1075	const char *map_name = bpf_map__name(map);
1076
1077	evsel = perf_evlist__find_evsel_by_str(evlist, term->val.str);
1078	if (!evsel) {
1079		pr_debug("Event (for '%s') '%s' doesn't exist\n",
1080			 map_name, term->val.str);
1081		return -BPF_LOADER_ERRNO__OBJCONF_MAP_NOEVT;
1082	}
1083
1084	def = bpf_map__def(map);
1085	if (IS_ERR(def)) {
1086		pr_debug("Unable to get map definition from '%s'\n",
1087			 map_name);
1088		return PTR_ERR(def);
1089	}
1090
1091	/*
1092	 * No need to check key_size and value_size:
1093	 * kernel has already checked them.
1094	 */
1095	if (def->type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
1096		pr_debug("Map %s type is not BPF_MAP_TYPE_PERF_EVENT_ARRAY\n",
1097			 map_name);
1098		return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1099	}
1100
1101	op = bpf_map__add_newop(map, term);
1102	if (IS_ERR(op))
1103		return PTR_ERR(op);
1104	op->op_type = BPF_MAP_OP_SET_EVSEL;
1105	op->v.evsel = evsel;
1106	return 0;
1107}
1108
1109static int
1110bpf_map__config_event(struct bpf_map *map,
1111		      struct parse_events_term *term,
1112		      struct perf_evlist *evlist)
1113{
1114	if (!term->err_val) {
1115		pr_debug("Config value not set\n");
1116		return -BPF_LOADER_ERRNO__OBJCONF_CONF;
1117	}
1118
1119	if (term->type_val != PARSE_EVENTS__TERM_TYPE_STR) {
1120		pr_debug("ERROR: wrong value type for 'event'\n");
1121		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE;
1122	}
1123
1124	return __bpf_map__config_event(map, term, evlist);
1125}
1126
1127struct bpf_obj_config__map_func {
1128	const char *config_opt;
1129	int (*config_func)(struct bpf_map *, struct parse_events_term *,
1130			   struct perf_evlist *);
1131};
1132
1133struct bpf_obj_config__map_func bpf_obj_config__map_funcs[] = {
1134	{"value", bpf_map__config_value},
1135	{"event", bpf_map__config_event},
1136};
1137
1138static int
1139config_map_indices_range_check(struct parse_events_term *term,
1140			       struct bpf_map *map,
1141			       const char *map_name)
1142{
1143	struct parse_events_array *array = &term->array;
1144	const struct bpf_map_def *def;
1145	unsigned int i;
1146
1147	if (!array->nr_ranges)
1148		return 0;
1149	if (!array->ranges) {
1150		pr_debug("ERROR: map %s: array->nr_ranges is %d but range array is NULL\n",
1151			 map_name, (int)array->nr_ranges);
1152		return -BPF_LOADER_ERRNO__INTERNAL;
1153	}
1154
1155	def = bpf_map__def(map);
1156	if (IS_ERR(def)) {
1157		pr_debug("ERROR: Unable to get map definition from '%s'\n",
1158			 map_name);
1159		return -BPF_LOADER_ERRNO__INTERNAL;
1160	}
1161
1162	for (i = 0; i < array->nr_ranges; i++) {
1163		unsigned int start = array->ranges[i].start;
1164		size_t length = array->ranges[i].length;
1165		unsigned int idx = start + length - 1;
1166
1167		if (idx >= def->max_entries) {
1168			pr_debug("ERROR: index %d too large\n", idx);
1169			return -BPF_LOADER_ERRNO__OBJCONF_MAP_IDX2BIG;
1170		}
1171	}
1172	return 0;
1173}
1174
1175static int
1176bpf__obj_config_map(struct bpf_object *obj,
1177		    struct parse_events_term *term,
1178		    struct perf_evlist *evlist,
1179		    int *key_scan_pos)
1180{
1181	/* key is "map:<mapname>.<config opt>" */
1182	char *map_name = strdup(term->config + sizeof("map:") - 1);
1183	struct bpf_map *map;
1184	int err = -BPF_LOADER_ERRNO__OBJCONF_OPT;
1185	char *map_opt;
1186	size_t i;
1187
1188	if (!map_name)
1189		return -ENOMEM;
1190
1191	map_opt = strchr(map_name, '.');
1192	if (!map_opt) {
1193		pr_debug("ERROR: Invalid map config: %s\n", map_name);
1194		goto out;
1195	}
1196
1197	*map_opt++ = '\0';
1198	if (*map_opt == '\0') {
1199		pr_debug("ERROR: Invalid map option: %s\n", term->config);
1200		goto out;
1201	}
1202
1203	map = bpf_object__find_map_by_name(obj, map_name);
1204	if (!map) {
1205		pr_debug("ERROR: Map %s doesn't exist\n", map_name);
1206		err = -BPF_LOADER_ERRNO__OBJCONF_MAP_NOTEXIST;
1207		goto out;
1208	}
1209
1210	*key_scan_pos += strlen(map_opt);
1211	err = config_map_indices_range_check(term, map, map_name);
1212	if (err)
1213		goto out;
1214	*key_scan_pos -= strlen(map_opt);
1215
1216	for (i = 0; i < ARRAY_SIZE(bpf_obj_config__map_funcs); i++) {
1217		struct bpf_obj_config__map_func *func =
1218				&bpf_obj_config__map_funcs[i];
1219
1220		if (strcmp(map_opt, func->config_opt) == 0) {
1221			err = func->config_func(map, term, evlist);
1222			goto out;
1223		}
1224	}
1225
1226	pr_debug("ERROR: Invalid map config option '%s'\n", map_opt);
1227	err = -BPF_LOADER_ERRNO__OBJCONF_MAP_OPT;
1228out:
1229	free(map_name);
1230	if (!err)
1231		key_scan_pos += strlen(map_opt);
1232	return err;
1233}
1234
1235int bpf__config_obj(struct bpf_object *obj,
1236		    struct parse_events_term *term,
1237		    struct perf_evlist *evlist,
1238		    int *error_pos)
1239{
1240	int key_scan_pos = 0;
1241	int err;
1242
1243	if (!obj || !term || !term->config)
1244		return -EINVAL;
1245
1246	if (!prefixcmp(term->config, "map:")) {
1247		key_scan_pos = sizeof("map:") - 1;
1248		err = bpf__obj_config_map(obj, term, evlist, &key_scan_pos);
1249		goto out;
1250	}
1251	err = -BPF_LOADER_ERRNO__OBJCONF_OPT;
1252out:
1253	if (error_pos)
1254		*error_pos = key_scan_pos;
1255	return err;
1256
1257}
1258
1259typedef int (*map_config_func_t)(const char *name, int map_fd,
1260				 const struct bpf_map_def *pdef,
1261				 struct bpf_map_op *op,
1262				 void *pkey, void *arg);
1263
1264static int
1265foreach_key_array_all(map_config_func_t func,
1266		      void *arg, const char *name,
1267		      int map_fd, const struct bpf_map_def *pdef,
1268		      struct bpf_map_op *op)
1269{
1270	unsigned int i;
1271	int err;
1272
1273	for (i = 0; i < pdef->max_entries; i++) {
1274		err = func(name, map_fd, pdef, op, &i, arg);
1275		if (err) {
1276			pr_debug("ERROR: failed to insert value to %s[%u]\n",
1277				 name, i);
1278			return err;
1279		}
1280	}
1281	return 0;
1282}
1283
1284static int
1285foreach_key_array_ranges(map_config_func_t func, void *arg,
1286			 const char *name, int map_fd,
1287			 const struct bpf_map_def *pdef,
1288			 struct bpf_map_op *op)
1289{
1290	unsigned int i, j;
1291	int err;
1292
1293	for (i = 0; i < op->k.array.nr_ranges; i++) {
1294		unsigned int start = op->k.array.ranges[i].start;
1295		size_t length = op->k.array.ranges[i].length;
1296
1297		for (j = 0; j < length; j++) {
1298			unsigned int idx = start + j;
1299
1300			err = func(name, map_fd, pdef, op, &idx, arg);
1301			if (err) {
1302				pr_debug("ERROR: failed to insert value to %s[%u]\n",
1303					 name, idx);
1304				return err;
1305			}
1306		}
1307	}
1308	return 0;
1309}
1310
1311static int
1312bpf_map_config_foreach_key(struct bpf_map *map,
1313			   map_config_func_t func,
1314			   void *arg)
1315{
1316	int err, map_fd;
1317	struct bpf_map_op *op;
1318	const struct bpf_map_def *def;
1319	const char *name = bpf_map__name(map);
1320	struct bpf_map_priv *priv = bpf_map__priv(map);
1321
1322	if (IS_ERR(priv)) {
1323		pr_debug("ERROR: failed to get private from map %s\n", name);
1324		return -BPF_LOADER_ERRNO__INTERNAL;
1325	}
1326	if (!priv || list_empty(&priv->ops_list)) {
1327		pr_debug("INFO: nothing to config for map %s\n", name);
1328		return 0;
1329	}
1330
1331	def = bpf_map__def(map);
1332	if (IS_ERR(def)) {
1333		pr_debug("ERROR: failed to get definition from map %s\n", name);
1334		return -BPF_LOADER_ERRNO__INTERNAL;
1335	}
1336	map_fd = bpf_map__fd(map);
1337	if (map_fd < 0) {
1338		pr_debug("ERROR: failed to get fd from map %s\n", name);
1339		return map_fd;
1340	}
1341
1342	list_for_each_entry(op, &priv->ops_list, list) {
1343		switch (def->type) {
1344		case BPF_MAP_TYPE_ARRAY:
1345		case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
1346			switch (op->key_type) {
1347			case BPF_MAP_KEY_ALL:
1348				err = foreach_key_array_all(func, arg, name,
1349							    map_fd, def, op);
1350				break;
1351			case BPF_MAP_KEY_RANGES:
1352				err = foreach_key_array_ranges(func, arg, name,
1353							       map_fd, def,
1354							       op);
1355				break;
1356			default:
1357				pr_debug("ERROR: keytype for map '%s' invalid\n",
1358					 name);
1359				return -BPF_LOADER_ERRNO__INTERNAL;
1360			}
1361			if (err)
1362				return err;
1363			break;
1364		default:
1365			pr_debug("ERROR: type of '%s' incorrect\n", name);
1366			return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1367		}
1368	}
1369
1370	return 0;
1371}
1372
1373static int
1374apply_config_value_for_key(int map_fd, void *pkey,
1375			   size_t val_size, u64 val)
1376{
1377	int err = 0;
1378
1379	switch (val_size) {
1380	case 1: {
1381		u8 _val = (u8)(val);
1382		err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1383		break;
1384	}
1385	case 2: {
1386		u16 _val = (u16)(val);
1387		err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1388		break;
1389	}
1390	case 4: {
1391		u32 _val = (u32)(val);
1392		err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1393		break;
1394	}
1395	case 8: {
1396		err = bpf_map_update_elem(map_fd, pkey, &val, BPF_ANY);
1397		break;
1398	}
1399	default:
1400		pr_debug("ERROR: invalid value size\n");
1401		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE;
1402	}
1403	if (err && errno)
1404		err = -errno;
1405	return err;
1406}
1407
1408static int
1409apply_config_evsel_for_key(const char *name, int map_fd, void *pkey,
1410			   struct perf_evsel *evsel)
1411{
1412	struct xyarray *xy = evsel->fd;
1413	struct perf_event_attr *attr;
1414	unsigned int key, events;
1415	bool check_pass = false;
1416	int *evt_fd;
1417	int err;
1418
1419	if (!xy) {
1420		pr_debug("ERROR: evsel not ready for map %s\n", name);
1421		return -BPF_LOADER_ERRNO__INTERNAL;
1422	}
1423
1424	if (xy->row_size / xy->entry_size != 1) {
1425		pr_debug("ERROR: Dimension of target event is incorrect for map %s\n",
1426			 name);
1427		return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM;
1428	}
1429
1430	attr = &evsel->attr;
1431	if (attr->inherit) {
1432		pr_debug("ERROR: Can't put inherit event into map %s\n", name);
1433		return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH;
1434	}
1435
1436	if (perf_evsel__is_bpf_output(evsel))
1437		check_pass = true;
1438	if (attr->type == PERF_TYPE_RAW)
1439		check_pass = true;
1440	if (attr->type == PERF_TYPE_HARDWARE)
1441		check_pass = true;
1442	if (!check_pass) {
1443		pr_debug("ERROR: Event type is wrong for map %s\n", name);
1444		return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE;
1445	}
1446
1447	events = xy->entries / (xy->row_size / xy->entry_size);
1448	key = *((unsigned int *)pkey);
1449	if (key >= events) {
1450		pr_debug("ERROR: there is no event %d for map %s\n",
1451			 key, name);
1452		return -BPF_LOADER_ERRNO__OBJCONF_MAP_MAPSIZE;
1453	}
1454	evt_fd = xyarray__entry(xy, key, 0);
1455	err = bpf_map_update_elem(map_fd, pkey, evt_fd, BPF_ANY);
1456	if (err && errno)
1457		err = -errno;
1458	return err;
1459}
1460
1461static int
1462apply_obj_config_map_for_key(const char *name, int map_fd,
1463			     const struct bpf_map_def *pdef,
1464			     struct bpf_map_op *op,
1465			     void *pkey, void *arg __maybe_unused)
1466{
1467	int err;
1468
1469	switch (op->op_type) {
1470	case BPF_MAP_OP_SET_VALUE:
1471		err = apply_config_value_for_key(map_fd, pkey,
1472						 pdef->value_size,
1473						 op->v.value);
1474		break;
1475	case BPF_MAP_OP_SET_EVSEL:
1476		err = apply_config_evsel_for_key(name, map_fd, pkey,
1477						 op->v.evsel);
1478		break;
1479	default:
1480		pr_debug("ERROR: unknown value type for '%s'\n", name);
1481		err = -BPF_LOADER_ERRNO__INTERNAL;
1482	}
1483	return err;
1484}
1485
1486static int
1487apply_obj_config_map(struct bpf_map *map)
1488{
1489	return bpf_map_config_foreach_key(map,
1490					  apply_obj_config_map_for_key,
1491					  NULL);
1492}
1493
1494static int
1495apply_obj_config_object(struct bpf_object *obj)
1496{
1497	struct bpf_map *map;
1498	int err;
1499
1500	bpf_map__for_each(map, obj) {
1501		err = apply_obj_config_map(map);
1502		if (err)
1503			return err;
1504	}
1505	return 0;
1506}
1507
1508int bpf__apply_obj_config(void)
1509{
1510	struct bpf_object *obj, *tmp;
1511	int err;
1512
1513	bpf_object__for_each_safe(obj, tmp) {
1514		err = apply_obj_config_object(obj);
1515		if (err)
1516			return err;
1517	}
1518
1519	return 0;
1520}
1521
1522#define bpf__for_each_map(pos, obj, objtmp)	\
1523	bpf_object__for_each_safe(obj, objtmp)	\
1524		bpf_map__for_each(pos, obj)
1525
1526#define bpf__for_each_stdout_map(pos, obj, objtmp)	\
1527	bpf__for_each_map(pos, obj, objtmp) 		\
1528		if (bpf_map__name(pos) && 		\
1529			(strcmp("__bpf_stdout__", 	\
1530				bpf_map__name(pos)) == 0))
1531
1532int bpf__setup_stdout(struct perf_evlist *evlist __maybe_unused)
1533{
1534	struct bpf_map_priv *tmpl_priv = NULL;
1535	struct bpf_object *obj, *tmp;
1536	struct perf_evsel *evsel = NULL;
1537	struct bpf_map *map;
1538	int err;
1539	bool need_init = false;
1540
1541	bpf__for_each_stdout_map(map, obj, tmp) {
1542		struct bpf_map_priv *priv = bpf_map__priv(map);
1543
1544		if (IS_ERR(priv))
1545			return -BPF_LOADER_ERRNO__INTERNAL;
1546
1547		/*
1548		 * No need to check map type: type should have been
1549		 * verified by kernel.
1550		 */
1551		if (!need_init && !priv)
1552			need_init = !priv;
1553		if (!tmpl_priv && priv)
1554			tmpl_priv = priv;
1555	}
1556
1557	if (!need_init)
1558		return 0;
1559
1560	if (!tmpl_priv) {
1561		err = parse_events(evlist, "bpf-output/no-inherit=1,name=__bpf_stdout__/",
1562				   NULL);
 
 
 
 
 
 
1563		if (err) {
1564			pr_debug("ERROR: failed to create bpf-output event\n");
1565			return -err;
1566		}
1567
1568		evsel = perf_evlist__last(evlist);
1569	}
1570
1571	bpf__for_each_stdout_map(map, obj, tmp) {
1572		struct bpf_map_priv *priv = bpf_map__priv(map);
1573
1574		if (IS_ERR(priv))
1575			return -BPF_LOADER_ERRNO__INTERNAL;
1576		if (priv)
1577			continue;
1578
1579		if (tmpl_priv) {
1580			priv = bpf_map_priv__clone(tmpl_priv);
1581			if (!priv)
1582				return -ENOMEM;
1583
1584			err = bpf_map__set_priv(map, priv, bpf_map_priv__clear);
1585			if (err) {
1586				bpf_map_priv__clear(map, priv);
1587				return err;
1588			}
1589		} else if (evsel) {
1590			struct bpf_map_op *op;
1591
1592			op = bpf_map__add_newop(map, NULL);
1593			if (IS_ERR(op))
1594				return PTR_ERR(op);
1595			op->op_type = BPF_MAP_OP_SET_EVSEL;
1596			op->v.evsel = evsel;
1597		}
1598	}
1599
1600	return 0;
 
 
 
 
 
 
1601}
1602
1603#define ERRNO_OFFSET(e)		((e) - __BPF_LOADER_ERRNO__START)
1604#define ERRCODE_OFFSET(c)	ERRNO_OFFSET(BPF_LOADER_ERRNO__##c)
1605#define NR_ERRNO	(__BPF_LOADER_ERRNO__END - __BPF_LOADER_ERRNO__START)
1606
1607static const char *bpf_loader_strerror_table[NR_ERRNO] = {
1608	[ERRCODE_OFFSET(CONFIG)]	= "Invalid config string",
1609	[ERRCODE_OFFSET(GROUP)]		= "Invalid group name",
1610	[ERRCODE_OFFSET(EVENTNAME)]	= "No event name found in config string",
1611	[ERRCODE_OFFSET(INTERNAL)]	= "BPF loader internal error",
1612	[ERRCODE_OFFSET(COMPILE)]	= "Error when compiling BPF scriptlet",
1613	[ERRCODE_OFFSET(PROGCONF_TERM)]	= "Invalid program config term in config string",
1614	[ERRCODE_OFFSET(PROLOGUE)]	= "Failed to generate prologue",
1615	[ERRCODE_OFFSET(PROLOGUE2BIG)]	= "Prologue too big for program",
1616	[ERRCODE_OFFSET(PROLOGUEOOB)]	= "Offset out of bound for prologue",
1617	[ERRCODE_OFFSET(OBJCONF_OPT)]	= "Invalid object config option",
1618	[ERRCODE_OFFSET(OBJCONF_CONF)]	= "Config value not set (missing '=')",
1619	[ERRCODE_OFFSET(OBJCONF_MAP_OPT)]	= "Invalid object map config option",
1620	[ERRCODE_OFFSET(OBJCONF_MAP_NOTEXIST)]	= "Target map doesn't exist",
1621	[ERRCODE_OFFSET(OBJCONF_MAP_VALUE)]	= "Incorrect value type for map",
1622	[ERRCODE_OFFSET(OBJCONF_MAP_TYPE)]	= "Incorrect map type",
1623	[ERRCODE_OFFSET(OBJCONF_MAP_KEYSIZE)]	= "Incorrect map key size",
1624	[ERRCODE_OFFSET(OBJCONF_MAP_VALUESIZE)]	= "Incorrect map value size",
1625	[ERRCODE_OFFSET(OBJCONF_MAP_NOEVT)]	= "Event not found for map setting",
1626	[ERRCODE_OFFSET(OBJCONF_MAP_MAPSIZE)]	= "Invalid map size for event setting",
1627	[ERRCODE_OFFSET(OBJCONF_MAP_EVTDIM)]	= "Event dimension too large",
1628	[ERRCODE_OFFSET(OBJCONF_MAP_EVTINH)]	= "Doesn't support inherit event",
1629	[ERRCODE_OFFSET(OBJCONF_MAP_EVTTYPE)]	= "Wrong event type for map",
1630	[ERRCODE_OFFSET(OBJCONF_MAP_IDX2BIG)]	= "Index too large",
1631};
1632
1633static int
1634bpf_loader_strerror(int err, char *buf, size_t size)
1635{
1636	char sbuf[STRERR_BUFSIZE];
1637	const char *msg;
1638
1639	if (!buf || !size)
1640		return -1;
1641
1642	err = err > 0 ? err : -err;
1643
1644	if (err >= __LIBBPF_ERRNO__START)
1645		return libbpf_strerror(err, buf, size);
1646
1647	if (err >= __BPF_LOADER_ERRNO__START && err < __BPF_LOADER_ERRNO__END) {
1648		msg = bpf_loader_strerror_table[ERRNO_OFFSET(err)];
1649		snprintf(buf, size, "%s", msg);
1650		buf[size - 1] = '\0';
1651		return 0;
1652	}
1653
1654	if (err >= __BPF_LOADER_ERRNO__END)
1655		snprintf(buf, size, "Unknown bpf loader error %d", err);
1656	else
1657		snprintf(buf, size, "%s",
1658			 str_error_r(err, sbuf, sizeof(sbuf)));
1659
1660	buf[size - 1] = '\0';
1661	return -1;
1662}
1663
1664#define bpf__strerror_head(err, buf, size) \
1665	char sbuf[STRERR_BUFSIZE], *emsg;\
1666	if (!size)\
1667		return 0;\
1668	if (err < 0)\
1669		err = -err;\
1670	bpf_loader_strerror(err, sbuf, sizeof(sbuf));\
1671	emsg = sbuf;\
1672	switch (err) {\
1673	default:\
1674		scnprintf(buf, size, "%s", emsg);\
1675		break;
1676
1677#define bpf__strerror_entry(val, fmt...)\
1678	case val: {\
1679		scnprintf(buf, size, fmt);\
1680		break;\
1681	}
1682
1683#define bpf__strerror_end(buf, size)\
1684	}\
1685	buf[size - 1] = '\0';
1686
1687int bpf__strerror_prepare_load(const char *filename, bool source,
1688			       int err, char *buf, size_t size)
1689{
1690	size_t n;
1691	int ret;
1692
1693	n = snprintf(buf, size, "Failed to load %s%s: ",
1694			 filename, source ? " from source" : "");
1695	if (n >= size) {
1696		buf[size - 1] = '\0';
1697		return 0;
1698	}
1699	buf += n;
1700	size -= n;
1701
1702	ret = bpf_loader_strerror(err, buf, size);
1703	buf[size - 1] = '\0';
1704	return ret;
1705}
1706
1707int bpf__strerror_probe(struct bpf_object *obj __maybe_unused,
1708			int err, char *buf, size_t size)
1709{
1710	bpf__strerror_head(err, buf, size);
1711	case BPF_LOADER_ERRNO__PROGCONF_TERM: {
1712		scnprintf(buf, size, "%s (add -v to see detail)", emsg);
1713		break;
1714	}
1715	bpf__strerror_entry(EEXIST, "Probe point exist. Try 'perf probe -d \"*\"' and set 'force=yes'");
1716	bpf__strerror_entry(EACCES, "You need to be root");
1717	bpf__strerror_entry(EPERM, "You need to be root, and /proc/sys/kernel/kptr_restrict should be 0");
1718	bpf__strerror_entry(ENOENT, "You need to check probing points in BPF file");
1719	bpf__strerror_end(buf, size);
1720	return 0;
1721}
1722
1723int bpf__strerror_load(struct bpf_object *obj,
1724		       int err, char *buf, size_t size)
1725{
1726	bpf__strerror_head(err, buf, size);
1727	case LIBBPF_ERRNO__KVER: {
1728		unsigned int obj_kver = bpf_object__kversion(obj);
1729		unsigned int real_kver;
1730
1731		if (fetch_kernel_version(&real_kver, NULL, 0)) {
1732			scnprintf(buf, size, "Unable to fetch kernel version");
1733			break;
1734		}
1735
1736		if (obj_kver != real_kver) {
1737			scnprintf(buf, size,
1738				  "'version' ("KVER_FMT") doesn't match running kernel ("KVER_FMT")",
1739				  KVER_PARAM(obj_kver),
1740				  KVER_PARAM(real_kver));
1741			break;
1742		}
1743
1744		scnprintf(buf, size, "Failed to load program for unknown reason");
1745		break;
1746	}
1747	bpf__strerror_end(buf, size);
1748	return 0;
1749}
1750
1751int bpf__strerror_config_obj(struct bpf_object *obj __maybe_unused,
1752			     struct parse_events_term *term __maybe_unused,
1753			     struct perf_evlist *evlist __maybe_unused,
1754			     int *error_pos __maybe_unused, int err,
1755			     char *buf, size_t size)
1756{
1757	bpf__strerror_head(err, buf, size);
1758	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE,
1759			    "Can't use this config term with this map type");
1760	bpf__strerror_end(buf, size);
1761	return 0;
1762}
1763
1764int bpf__strerror_apply_obj_config(int err, char *buf, size_t size)
1765{
1766	bpf__strerror_head(err, buf, size);
1767	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM,
1768			    "Cannot set event to BPF map in multi-thread tracing");
1769	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH,
1770			    "%s (Hint: use -i to turn off inherit)", emsg);
1771	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE,
1772			    "Can only put raw, hardware and BPF output event into a BPF map");
1773	bpf__strerror_end(buf, size);
1774	return 0;
1775}
1776
1777int bpf__strerror_setup_stdout(struct perf_evlist *evlist __maybe_unused,
1778			       int err, char *buf, size_t size)
1779{
1780	bpf__strerror_head(err, buf, size);
1781	bpf__strerror_end(buf, size);
1782	return 0;
1783}