Message-ID: <tip-1b36c03e356936d62abbe2accaae1573d3b66f14@git.kernel.org>
Date:   Thu, 29 Sep 2016 11:15:19 -0700
From:   tip-bot for Adrian Hunter <tipbot@...or.com>
To:     linux-tip-commits@...r.kernel.org
Cc:     mingo@...nel.org, linux-kernel@...r.kernel.org, jolsa@...hat.com,
        mhiramat@...nel.org, hpa@...or.com, acme@...hat.com,
        mathieu.poirier@...aro.org, tglx@...utronix.de,
        adrian.hunter@...el.com
Subject: [tip:perf/core] perf record: Add support for using symbols in
 address filters

Commit-ID:  1b36c03e356936d62abbe2accaae1573d3b66f14
Gitweb:     http://git.kernel.org/tip/1b36c03e356936d62abbe2accaae1573d3b66f14
Author:     Adrian Hunter <adrian.hunter@...el.com>
AuthorDate: Fri, 23 Sep 2016 17:38:39 +0300
Committer:  Arnaldo Carvalho de Melo <acme@...hat.com>
CommitDate: Thu, 29 Sep 2016 11:17:02 -0300

perf record: Add support for using symbols in address filters

Symbols come from either the DSO or /proc/kallsyms for the kernel.
Details of the functionality can be found in Documentation/perf-record.txt.

Signed-off-by: Adrian Hunter <adrian.hunter@...el.com>
Cc: Jiri Olsa <jolsa@...hat.com>
Cc: Masami Hiramatsu <mhiramat@...nel.org>
Cc: Mathieu Poirier <mathieu.poirier@...aro.org>
Link: http://lkml.kernel.org/r/1474641528-18776-8-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@...hat.com>
---
 tools/perf/Documentation/perf-record.txt |  55 ++-
 tools/perf/builtin-record.c              |  14 +-
 tools/perf/util/auxtrace.c               | 737 +++++++++++++++++++++++++++++++
 tools/perf/util/auxtrace.h               |  54 +++
 4 files changed, 857 insertions(+), 3 deletions(-)

diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
index babbb63..9233519 100644
--- a/tools/perf/Documentation/perf-record.txt
+++ b/tools/perf/Documentation/perf-record.txt
@@ -89,9 +89,62 @@ OPTIONS
 
 --filter=<filter>::
         Event filter. This option should follow a event selector (-e) which
-	selects tracepoint event(s). Multiple '--filter' options are combined
+	selects either tracepoint event(s) or a hardware trace PMU
+	(e.g. Intel PT or CoreSight).
+
+	- tracepoint filters
+
+	In the case of tracepoints, multiple '--filter' options are combined
 	using '&&'.
 
+	- address filters
+
+	A hardware trace PMU advertises its ability to accept a number of
+	address filters	by specifying a non-zero value in
+	/sys/bus/event_source/devices/<pmu>/nr_addr_filters.
+
+	Address filters have the format:
+
+	filter|start|stop|tracestop <start> [/ <size>] [@<file name>]
+
+	Where:
+	- 'filter': defines a region that will be traced.
+	- 'start': defines an address at which tracing will begin.
+	- 'stop': defines an address at which tracing will stop.
+	- 'tracestop': defines a region in which tracing will stop.
+
+	<file name> is the name of the object file, <start> is the offset to the
+	code to trace in that file, and <size> is the size of the region to
+	trace. 'start' and 'stop' filters need not specify a <size>.
+
+	If no object file is specified then the kernel is assumed, in which case
+	the start address must be a current kernel memory address.
+
+	<start> can also be specified by providing the name of a symbol. If the
+	symbol name is not unique, it can be disambiguated by inserting #n where
+	'n' selects the n'th symbol in address order. Alternately #0, #g or #G
+	select only a global symbol. <size> can also be specified by providing
+	the name of a symbol, in which case the size is calculated to the end
+	of that symbol. For 'filter' and 'tracestop' filters, if <size> is
+	omitted and <start> is a symbol, then the size is calculated to the end
+	of that symbol.
+
+	If <size> is omitted and <start> is '*', then the start and size will
+	be calculated from the first and last symbols, i.e. to trace the whole
+	file.
+
+	If symbol names (or '*') are provided, they must be surrounded by white
+	space.
+
+	The filter passed to the kernel is not necessarily the same as entered.
+	To see the filter that is passed, use the -v option.
+
+	The kernel may not be able to configure a trace region if it is not
+	within a single mapping.  MMAP events (or /proc/<pid>/maps) can be
+	examined to determine if that is a possibility.
+
+	Multiple filters can be separated with space or comma.
+
 --exclude-perf::
 	Don't record events issued by perf itself. This option should follow
 	a event selector (-e) which selects tracepoint event(s). It adds a
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 962adcf..67d2a90 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1581,6 +1581,18 @@ int cmd_record(int argc, const char **argv, const char *prefix __maybe_unused)
 	if (err)
 		goto out;
 
+	/*
+	 * Allow aliases to facilitate the lookup of symbols for address
+	 * filters. Refer to auxtrace_parse_filters().
+	 */
+	symbol_conf.allow_aliases = true;
+
+	symbol__init(NULL);
+
+	err = auxtrace_parse_filters(rec->evlist);
+	if (err)
+		goto out;
+
 	if (dry_run)
 		goto out;
 
@@ -1594,8 +1606,6 @@ int cmd_record(int argc, const char **argv, const char *prefix __maybe_unused)
 
 	err = -ENOMEM;
 
-	symbol__init(NULL);
-
 	if (symbol_conf.kptr_restrict)
 		pr_warning(
 "WARNING: Kernel address maps (/proc/{kallsyms,modules}) are restricted,\n"
diff --git a/tools/perf/util/auxtrace.c b/tools/perf/util/auxtrace.c
index c0aba8e..c5a6e0b 100644
--- a/tools/perf/util/auxtrace.c
+++ b/tools/perf/util/auxtrace.c
@@ -16,6 +16,10 @@
 #include <sys/types.h>
 #include <sys/mman.h>
 #include <stdbool.h>
+#include <ctype.h>
+#include <string.h>
+#include <limits.h>
+#include <errno.h>
 
 #include <linux/kernel.h>
 #include <linux/perf_event.h>
@@ -35,9 +39,14 @@
 #include "../perf.h"
 #include "util.h"
 #include "evlist.h"
+#include "dso.h"
+#include "map.h"
+#include "pmu.h"
+#include "evsel.h"
 #include "cpumap.h"
 #include "thread_map.h"
 #include "asm/bug.h"
+#include "symbol/kallsyms.h"
 #include "auxtrace.h"
 
 #include <linux/hash.h>
@@ -1399,3 +1408,731 @@ void *auxtrace_cache__lookup(struct auxtrace_cache *c, u32 key)
 
 	return NULL;
 }
+
+static void addr_filter__free_str(struct addr_filter *filt)
+{
+	free(filt->str);
+	filt->action   = NULL;
+	filt->sym_from = NULL;
+	filt->sym_to   = NULL;
+	filt->filename = NULL;
+	filt->str      = NULL;
+}
+
+static struct addr_filter *addr_filter__new(void)
+{
+	struct addr_filter *filt = zalloc(sizeof(*filt));
+
+	if (filt)
+		INIT_LIST_HEAD(&filt->list);
+
+	return filt;
+}
+
+static void addr_filter__free(struct addr_filter *filt)
+{
+	if (filt)
+		addr_filter__free_str(filt);
+	free(filt);
+}
+
+static void addr_filters__add(struct addr_filters *filts,
+			      struct addr_filter *filt)
+{
+	list_add_tail(&filt->list, &filts->head);
+	filts->cnt += 1;
+}
+
+static void addr_filters__del(struct addr_filters *filts,
+			      struct addr_filter *filt)
+{
+	list_del_init(&filt->list);
+	filts->cnt -= 1;
+}
+
+void addr_filters__init(struct addr_filters *filts)
+{
+	INIT_LIST_HEAD(&filts->head);
+	filts->cnt = 0;
+}
+
+void addr_filters__exit(struct addr_filters *filts)
+{
+	struct addr_filter *filt, *n;
+
+	list_for_each_entry_safe(filt, n, &filts->head, list) {
+		addr_filters__del(filts, filt);
+		addr_filter__free(filt);
+	}
+}
+
+static int parse_num_or_str(char **inp, u64 *num, const char **str,
+			    const char *str_delim)
+{
+	*inp += strspn(*inp, " ");
+
+	if (isdigit(**inp)) {
+		char *endptr;
+
+		if (!num)
+			return -EINVAL;
+		errno = 0;
+		*num = strtoull(*inp, &endptr, 0);
+		if (errno)
+			return -errno;
+		if (endptr == *inp)
+			return -EINVAL;
+		*inp = endptr;
+	} else {
+		size_t n;
+
+		if (!str)
+			return -EINVAL;
+		*inp += strspn(*inp, " ");
+		*str = *inp;
+		n = strcspn(*inp, str_delim);
+		if (!n)
+			return -EINVAL;
+		*inp += n;
+		if (**inp) {
+			**inp = '\0';
+			*inp += 1;
+		}
+	}
+	return 0;
+}
+
+static int parse_action(struct addr_filter *filt)
+{
+	if (!strcmp(filt->action, "filter")) {
+		filt->start = true;
+		filt->range = true;
+	} else if (!strcmp(filt->action, "start")) {
+		filt->start = true;
+	} else if (!strcmp(filt->action, "stop")) {
+		filt->start = false;
+	} else if (!strcmp(filt->action, "tracestop")) {
+		filt->start = false;
+		filt->range = true;
+		filt->action += 5; /* Change 'tracestop' to 'stop' */
+	} else {
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int parse_sym_idx(char **inp, int *idx)
+{
+	*idx = -1;
+
+	*inp += strspn(*inp, " ");
+
+	if (**inp != '#')
+		return 0;
+
+	*inp += 1;
+
+	if (**inp == 'g' || **inp == 'G') {
+		*inp += 1;
+		*idx = 0;
+	} else {
+		unsigned long num;
+		char *endptr;
+
+		errno = 0;
+		num = strtoul(*inp, &endptr, 0);
+		if (errno)
+			return -errno;
+		if (endptr == *inp || num > INT_MAX)
+			return -EINVAL;
+		*inp = endptr;
+		*idx = num;
+	}
+
+	return 0;
+}
+
+static int parse_addr_size(char **inp, u64 *num, const char **str, int *idx)
+{
+	int err = parse_num_or_str(inp, num, str, " ");
+
+	if (!err && *str)
+		err = parse_sym_idx(inp, idx);
+
+	return err;
+}
+
+static int parse_one_filter(struct addr_filter *filt, const char **filter_inp)
+{
+	char *fstr;
+	int err;
+
+	filt->str = fstr = strdup(*filter_inp);
+	if (!fstr)
+		return -ENOMEM;
+
+	err = parse_num_or_str(&fstr, NULL, &filt->action, " ");
+	if (err)
+		goto out_err;
+
+	err = parse_action(filt);
+	if (err)
+		goto out_err;
+
+	err = parse_addr_size(&fstr, &filt->addr, &filt->sym_from,
+			      &filt->sym_from_idx);
+	if (err)
+		goto out_err;
+
+	fstr += strspn(fstr, " ");
+
+	if (*fstr == '/') {
+		fstr += 1;
+		err = parse_addr_size(&fstr, &filt->size, &filt->sym_to,
+				      &filt->sym_to_idx);
+		if (err)
+			goto out_err;
+		filt->range = true;
+	}
+
+	fstr += strspn(fstr, " ");
+
+	if (*fstr == '@') {
+		fstr += 1;
+		err = parse_num_or_str(&fstr, NULL, &filt->filename, " ,");
+		if (err)
+			goto out_err;
+	}
+
+	fstr += strspn(fstr, " ,");
+
+	*filter_inp += fstr - filt->str;
+
+	return 0;
+
+out_err:
+	addr_filter__free_str(filt);
+
+	return err;
+}
+
+int addr_filters__parse_bare_filter(struct addr_filters *filts,
+				    const char *filter)
+{
+	struct addr_filter *filt;
+	const char *fstr = filter;
+	int err;
+
+	while (*fstr) {
+		filt = addr_filter__new();
+		err = parse_one_filter(filt, &fstr);
+		if (err) {
+			addr_filter__free(filt);
+			addr_filters__exit(filts);
+			return err;
+		}
+		addr_filters__add(filts, filt);
+	}
+
+	return 0;
+}
+
+struct sym_args {
+	const char	*name;
+	u64		start;
+	u64		size;
+	int		idx;
+	int		cnt;
+	bool		started;
+	bool		global;
+	bool		selected;
+	bool		duplicate;
+	bool		near;
+};
+
+static bool kern_sym_match(struct sym_args *args, const char *name, char type)
+{
+	/* A function with the same name, and global or the n'th found or any */
+	return symbol_type__is_a(type, MAP__FUNCTION) &&
+	       !strcmp(name, args->name) &&
+	       ((args->global && isupper(type)) ||
+		(args->selected && ++(args->cnt) == args->idx) ||
+		(!args->global && !args->selected));
+}
+
+static int find_kern_sym_cb(void *arg, const char *name, char type, u64 start)
+{
+	struct sym_args *args = arg;
+
+	if (args->started) {
+		if (!args->size)
+			args->size = start - args->start;
+		if (args->selected) {
+			if (args->size)
+				return 1;
+		} else if (kern_sym_match(args, name, type)) {
+			args->duplicate = true;
+			return 1;
+		}
+	} else if (kern_sym_match(args, name, type)) {
+		args->started = true;
+		args->start = start;
+	}
+
+	return 0;
+}
+
+static int print_kern_sym_cb(void *arg, const char *name, char type, u64 start)
+{
+	struct sym_args *args = arg;
+
+	if (kern_sym_match(args, name, type)) {
+		pr_err("#%d\t0x%"PRIx64"\t%c\t%s\n",
+		       ++args->cnt, start, type, name);
+		args->near = true;
+	} else if (args->near) {
+		args->near = false;
+		pr_err("\t\twhich is near\t\t%s\n", name);
+	}
+
+	return 0;
+}
+
+static int sym_not_found_error(const char *sym_name, int idx)
+{
+	if (idx > 0) {
+		pr_err("N'th occurrence (N=%d) of symbol '%s' not found.\n",
+		       idx, sym_name);
+	} else if (!idx) {
+		pr_err("Global symbol '%s' not found.\n", sym_name);
+	} else {
+		pr_err("Symbol '%s' not found.\n", sym_name);
+	}
+	pr_err("Note that symbols must be functions.\n");
+
+	return -EINVAL;
+}
+
+static int find_kern_sym(const char *sym_name, u64 *start, u64 *size, int idx)
+{
+	struct sym_args args = {
+		.name = sym_name,
+		.idx = idx,
+		.global = !idx,
+		.selected = idx > 0,
+	};
+	int err;
+
+	*start = 0;
+	*size = 0;
+
+	err = kallsyms__parse("/proc/kallsyms", &args, find_kern_sym_cb);
+	if (err < 0) {
+		pr_err("Failed to parse /proc/kallsyms\n");
+		return err;
+	}
+
+	if (args.duplicate) {
+		pr_err("Multiple kernel symbols with name '%s'\n", sym_name);
+		args.cnt = 0;
+		kallsyms__parse("/proc/kallsyms", &args, print_kern_sym_cb);
+		pr_err("Disambiguate symbol name by inserting #n after the name e.g. %s #2\n",
+		       sym_name);
+		pr_err("Or select a global symbol by inserting #0 or #g or #G\n");
+		return -EINVAL;
+	}
+
+	if (!args.started) {
+		pr_err("Kernel symbol lookup: ");
+		return sym_not_found_error(sym_name, idx);
+	}
+
+	*start = args.start;
+	*size = args.size;
+
+	return 0;
+}
+
+static int find_entire_kern_cb(void *arg, const char *name __maybe_unused,
+			       char type, u64 start)
+{
+	struct sym_args *args = arg;
+
+	if (!symbol_type__is_a(type, MAP__FUNCTION))
+		return 0;
+
+	if (!args->started) {
+		args->started = true;
+		args->start = start;
+	}
+	/* Don't know exactly where the kernel ends, so we add a page */
+	args->size = round_up(start, page_size) + page_size - args->start;
+
+	return 0;
+}
+
+static int addr_filter__entire_kernel(struct addr_filter *filt)
+{
+	struct sym_args args = { .started = false };
+	int err;
+
+	err = kallsyms__parse("/proc/kallsyms", &args, find_entire_kern_cb);
+	if (err < 0 || !args.started) {
+		pr_err("Failed to parse /proc/kallsyms\n");
+		return err;
+	}
+
+	filt->addr = args.start;
+	filt->size = args.size;
+
+	return 0;
+}
+
+static int check_end_after_start(struct addr_filter *filt, u64 start, u64 size)
+{
+	if (start + size >= filt->addr)
+		return 0;
+
+	if (filt->sym_from) {
+		pr_err("Symbol '%s' (0x%"PRIx64") comes before '%s' (0x%"PRIx64")\n",
+		       filt->sym_to, start, filt->sym_from, filt->addr);
+	} else {
+		pr_err("Symbol '%s' (0x%"PRIx64") comes before address 0x%"PRIx64")\n",
+		       filt->sym_to, start, filt->addr);
+	}
+
+	return -EINVAL;
+}
+
+static int addr_filter__resolve_kernel_syms(struct addr_filter *filt)
+{
+	bool no_size = false;
+	u64 start, size;
+	int err;
+
+	if (symbol_conf.kptr_restrict) {
+		pr_err("Kernel addresses are restricted. Unable to resolve kernel symbols.\n");
+		return -EINVAL;
+	}
+
+	if (filt->sym_from && !strcmp(filt->sym_from, "*"))
+		return addr_filter__entire_kernel(filt);
+
+	if (filt->sym_from) {
+		err = find_kern_sym(filt->sym_from, &start, &size,
+				    filt->sym_from_idx);
+		if (err)
+			return err;
+		filt->addr = start;
+		if (filt->range && !filt->size && !filt->sym_to) {
+			filt->size = size;
+			no_size = !!size;
+		}
+	}
+
+	if (filt->sym_to) {
+		err = find_kern_sym(filt->sym_to, &start, &size,
+				    filt->sym_to_idx);
+		if (err)
+			return err;
+
+		err = check_end_after_start(filt, start, size);
+		if (err)
+			return err;
+		filt->size = start + size - filt->addr;
+		no_size = !!size;
+	}
+
+	/* The very last symbol in kallsyms does not imply a particular size */
+	if (no_size) {
+		pr_err("Cannot determine size of symbol '%s'\n",
+		       filt->sym_to ? filt->sym_to : filt->sym_from);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static struct dso *load_dso(const char *name)
+{
+	struct map *map;
+	struct dso *dso;
+
+	map = dso__new_map(name);
+	if (!map)
+		return NULL;
+
+	map__load(map);
+
+	dso = dso__get(map->dso);
+
+	map__put(map);
+
+	return dso;
+}
+
+static bool dso_sym_match(struct symbol *sym, const char *name, int *cnt,
+			  int idx)
+{
+	/* Same name, and global or the n'th found or any */
+	return !arch__compare_symbol_names(name, sym->name) &&
+	       ((!idx && sym->binding == STB_GLOBAL) ||
+		(idx > 0 && ++*cnt == idx) ||
+		idx < 0);
+}
+
+static void print_duplicate_syms(struct dso *dso, const char *sym_name)
+{
+	struct symbol *sym;
+	bool near = false;
+	int cnt = 0;
+
+	pr_err("Multiple symbols with name '%s'\n", sym_name);
+
+	sym = dso__first_symbol(dso, MAP__FUNCTION);
+	while (sym) {
+		if (dso_sym_match(sym, sym_name, &cnt, -1)) {
+			pr_err("#%d\t0x%"PRIx64"\t%c\t%s\n",
+			       ++cnt, sym->start,
+			       sym->binding == STB_GLOBAL ? 'g' :
+			       sym->binding == STB_LOCAL  ? 'l' : 'w',
+			       sym->name);
+			near = true;
+		} else if (near) {
+			near = false;
+			pr_err("\t\twhich is near\t\t%s\n", sym->name);
+		}
+		sym = dso__next_symbol(sym);
+	}
+
+	pr_err("Disambiguate symbol name by inserting #n after the name e.g. %s #2\n",
+	       sym_name);
+	pr_err("Or select a global symbol by inserting #0 or #g or #G\n");
+}
+
+static int find_dso_sym(struct dso *dso, const char *sym_name, u64 *start,
+			u64 *size, int idx)
+{
+	struct symbol *sym;
+	int cnt = 0;
+
+	*start = 0;
+	*size = 0;
+
+	sym = dso__first_symbol(dso, MAP__FUNCTION);
+	while (sym) {
+		if (*start) {
+			if (!*size)
+				*size = sym->start - *start;
+			if (idx > 0) {
+				if (*size)
+					return 1;
+			} else if (dso_sym_match(sym, sym_name, &cnt, idx)) {
+				print_duplicate_syms(dso, sym_name);
+				return -EINVAL;
+			}
+		} else if (dso_sym_match(sym, sym_name, &cnt, idx)) {
+			*start = sym->start;
+			*size = sym->end - sym->start;
+		}
+		sym = dso__next_symbol(sym);
+	}
+
+	if (!*start)
+		return sym_not_found_error(sym_name, idx);
+
+	return 0;
+}
+
+static int addr_filter__entire_dso(struct addr_filter *filt, struct dso *dso)
+{
+	struct symbol *first_sym = dso__first_symbol(dso, MAP__FUNCTION);
+	struct symbol *last_sym = dso__last_symbol(dso, MAP__FUNCTION);
+
+	if (!first_sym || !last_sym) {
+		pr_err("Failed to determine filter for %s\nNo symbols found.\n",
+		       filt->filename);
+		return -EINVAL;
+	}
+
+	filt->addr = first_sym->start;
+	filt->size = last_sym->end - first_sym->start;
+
+	return 0;
+}
+
+static int addr_filter__resolve_syms(struct addr_filter *filt)
+{
+	u64 start, size;
+	struct dso *dso;
+	int err = 0;
+
+	if (!filt->sym_from && !filt->sym_to)
+		return 0;
+
+	if (!filt->filename)
+		return addr_filter__resolve_kernel_syms(filt);
+
+	dso = load_dso(filt->filename);
+	if (!dso) {
+		pr_err("Failed to load symbols from: %s\n", filt->filename);
+		return -EINVAL;
+	}
+
+	if (filt->sym_from && !strcmp(filt->sym_from, "*")) {
+		err = addr_filter__entire_dso(filt, dso);
+		goto put_dso;
+	}
+
+	if (filt->sym_from) {
+		err = find_dso_sym(dso, filt->sym_from, &start, &size,
+				   filt->sym_from_idx);
+		if (err)
+			goto put_dso;
+		filt->addr = start;
+		if (filt->range && !filt->size && !filt->sym_to)
+			filt->size = size;
+	}
+
+	if (filt->sym_to) {
+		err = find_dso_sym(dso, filt->sym_to, &start, &size,
+				   filt->sym_to_idx);
+		if (err)
+			goto put_dso;
+
+		err = check_end_after_start(filt, start, size);
+		if (err)
+			return err;
+
+		filt->size = start + size - filt->addr;
+	}
+
+put_dso:
+	dso__put(dso);
+
+	return err;
+}
+
+static char *addr_filter__to_str(struct addr_filter *filt)
+{
+	char filename_buf[PATH_MAX];
+	const char *at = "";
+	const char *fn = "";
+	char *filter;
+	int err;
+
+	if (filt->filename) {
+		at = "@";
+		fn = realpath(filt->filename, filename_buf);
+		if (!fn)
+			return NULL;
+	}
+
+	if (filt->range) {
+		err = asprintf(&filter, "%s 0x%"PRIx64"/0x%"PRIx64"%s%s",
+			       filt->action, filt->addr, filt->size, at, fn);
+	} else {
+		err = asprintf(&filter, "%s 0x%"PRIx64"%s%s",
+			       filt->action, filt->addr, at, fn);
+	}
+
+	return err < 0 ? NULL : filter;
+}
+
+static int parse_addr_filter(struct perf_evsel *evsel, const char *filter,
+			     int max_nr)
+{
+	struct addr_filters filts;
+	struct addr_filter *filt;
+	int err;
+
+	addr_filters__init(&filts);
+
+	err = addr_filters__parse_bare_filter(&filts, filter);
+	if (err)
+		goto out_exit;
+
+	if (filts.cnt > max_nr) {
+		pr_err("Error: number of address filters (%d) exceeds maximum (%d)\n",
+		       filts.cnt, max_nr);
+		err = -EINVAL;
+		goto out_exit;
+	}
+
+	list_for_each_entry(filt, &filts.head, list) {
+		char *new_filter;
+
+		err = addr_filter__resolve_syms(filt);
+		if (err)
+			goto out_exit;
+
+		new_filter = addr_filter__to_str(filt);
+		if (!new_filter) {
+			err = -ENOMEM;
+			goto out_exit;
+		}
+
+		if (perf_evsel__append_addr_filter(evsel, new_filter)) {
+			err = -ENOMEM;
+			goto out_exit;
+		}
+	}
+
+out_exit:
+	addr_filters__exit(&filts);
+
+	if (err) {
+		pr_err("Failed to parse address filter: '%s'\n", filter);
+		pr_err("Filter format is: filter|start|stop|tracestop <start symbol or address> [/ <end symbol or size>] [@<file name>]\n");
+		pr_err("Where multiple filters are separated by space or comma.\n");
+	}
+
+	return err;
+}
+
+static struct perf_pmu *perf_evsel__find_pmu(struct perf_evsel *evsel)
+{
+	struct perf_pmu *pmu = NULL;
+
+	while ((pmu = perf_pmu__scan(pmu)) != NULL) {
+		if (pmu->type == evsel->attr.type)
+			break;
+	}
+
+	return pmu;
+}
+
+static int perf_evsel__nr_addr_filter(struct perf_evsel *evsel)
+{
+	struct perf_pmu *pmu = perf_evsel__find_pmu(evsel);
+	int nr_addr_filters = 0;
+
+	if (!pmu)
+		return 0;
+
+	perf_pmu__scan_file(pmu, "nr_addr_filters", "%d", &nr_addr_filters);
+
+	return nr_addr_filters;
+}
+
+int auxtrace_parse_filters(struct perf_evlist *evlist)
+{
+	struct perf_evsel *evsel;
+	char *filter;
+	int err, max_nr;
+
+	evlist__for_each_entry(evlist, evsel) {
+		filter = evsel->filter;
+		max_nr = perf_evsel__nr_addr_filter(evsel);
+		if (!filter || !max_nr)
+			continue;
+		evsel->filter = NULL;
+		err = parse_addr_filter(evsel, filter, max_nr);
+		free(filter);
+		if (err)
+			return err;
+		pr_debug("Address filter: %s\n", evsel->filter);
+	}
+
+	return 0;
+}
diff --git a/tools/perf/util/auxtrace.h b/tools/perf/util/auxtrace.h
index 09286f1..26fb1ee 100644
--- a/tools/perf/util/auxtrace.h
+++ b/tools/perf/util/auxtrace.h
@@ -318,6 +318,48 @@ struct auxtrace_record {
 	unsigned int alignment;
 };
 
+/**
+ * struct addr_filter - address filter.
+ * @list: list node
+ * @range: true if it is a range filter
+ * @start: true if action is 'filter' or 'start'
+ * @action: 'filter', 'start' or 'stop' ('tracestop' is accepted but converted
+ *          to 'stop')
+ * @sym_from: symbol name for the filter address
+ * @sym_to: symbol name that determines the filter size
+ * @sym_from_idx: selects n'th from symbols with the same name (0 means global
+ *                and less than 0 means symbol must be unique)
+ * @sym_to_idx: same as @sym_from_idx but for @sym_to
+ * @addr: filter address
+ * @size: filter region size (for range filters)
+ * @filename: DSO file name or NULL for the kernel
+ * @str: allocated string that contains the other string members
+ */
+struct addr_filter {
+	struct list_head	list;
+	bool			range;
+	bool			start;
+	const char		*action;
+	const char		*sym_from;
+	const char		*sym_to;
+	int			sym_from_idx;
+	int			sym_to_idx;
+	u64			addr;
+	u64			size;
+	const char		*filename;
+	char			*str;
+};
+
+/**
+ * struct addr_filters - list of address filters.
+ * @head: list of address filters
+ * @cnt: number of address filters
+ */
+struct addr_filters {
+	struct list_head	head;
+	int			cnt;
+};
+
 #ifdef HAVE_AUXTRACE_SUPPORT
 
 /*
@@ -482,6 +524,12 @@ void perf_session__auxtrace_error_inc(struct perf_session *session,
 				      union perf_event *event);
 void events_stats__auxtrace_error_warn(const struct events_stats *stats);
 
+void addr_filters__init(struct addr_filters *filts);
+void addr_filters__exit(struct addr_filters *filts);
+int addr_filters__parse_bare_filter(struct addr_filters *filts,
+				    const char *filter);
+int auxtrace_parse_filters(struct perf_evlist *evlist);
+
 static inline int auxtrace__process_event(struct perf_session *session,
 					  union perf_event *event,
 					  struct perf_sample *sample,
@@ -640,6 +688,12 @@ void auxtrace_index__free(struct list_head *head __maybe_unused)
 {
 }
 
+static inline
+int auxtrace_parse_filters(struct perf_evlist *evlist __maybe_unused)
+{
+	return 0;
+}
+
 int auxtrace_mmap__mmap(struct auxtrace_mmap *mm,
 			struct auxtrace_mmap_params *mp,
 			void *userpg, int fd);

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