Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

New features:

  - Allow filtering out of perf's PID via 'perf record --exclude-perf'. (Wang Nan)

  - 'perf trace' now supports syscall groups, like strace, i.e:

      $ trace -e file touch file

    Will expand 'file' into multiple, file related, syscalls. More work needed to
    add extra groups for other syscall groups, and also to complement what was
    added for the 'file' group, included as a proof of concept. (Arnaldo Carvalho de Melo)

  - Add lock_pi stresser to 'perf bench futex', to test the kernel code
    related to FUTEX_(UN)LOCK_PI. (Davidlohr Bueso)

User visible fixes:

  - Apply --filter to all events in a glob matching, not just the last one. (Wang Nan)

Documentation changes:

  - Document setting '-e pmu/period=N/' in the 'perf record' man page. (Kan Liang)

Infrastructure changes:

  - 'perf probe' code simplifications and movements to separate files. (Masami Hiramatsu)

  - Fix makefile generation under 'dash'. (Sergei Trofimovich)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

17 files changed, 527 insertions, 345 deletions

diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index d2d318c59b37..a1e5168dc1fb 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -79,6 +79,7 @@ libperf-$(CONFIG_AUXTRACE) += auxtrace.o
 libperf-y += parse-branch-options.o
 
 libperf-$(CONFIG_LIBELF) += symbol-elf.o
+libperf-$(CONFIG_LIBELF) += probe-file.o
 libperf-$(CONFIG_LIBELF) += probe-event.o
 
 ifndef CONFIG_LIBELF
diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
index 1f6fc2323ef9..4a2c2f0ead41 100644
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -124,7 +124,7 @@ static char *build_id__filename(const char *sbuild_id, char *bf, size_t size)
 
 char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size)
 {
-	char build_id_hex[BUILD_ID_SIZE * 2 + 1];
+	char build_id_hex[SBUILD_ID_SIZE];
 
 	if (!dso->has_build_id)
 		return NULL;
@@ -291,7 +291,7 @@ int build_id_cache__list_build_ids(const char *pathname,
 	struct dirent *d;
 	int ret = 0;
 
-	list = strlist__new(true, NULL);
+	list = strlist__new(NULL, NULL);
 	dir_name = build_id_cache__dirname_from_path(pathname, false, false);
 	if (!list || !dir_name) {
 		ret = -ENOMEM;
@@ -384,7 +384,7 @@ static int build_id_cache__add_b(const u8 *build_id, size_t build_id_size,
 				 const char *name, bool is_kallsyms,
 				 bool is_vdso)
 {
-	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
+	char sbuild_id[SBUILD_ID_SIZE];
 
 	build_id__sprintf(build_id, build_id_size, sbuild_id);
 
diff --git a/tools/perf/util/build-id.h b/tools/perf/util/build-id.h
index 85011222cc14..ce2f493f057a 100644
--- a/tools/perf/util/build-id.h
+++ b/tools/perf/util/build-id.h
@@ -1,7 +1,8 @@
 #ifndef PERF_BUILD_ID_H_
 #define PERF_BUILD_ID_H_ 1
 
-#define BUILD_ID_SIZE 20
+#define BUILD_ID_SIZE	20
+#define SBUILD_ID_SIZE	(BUILD_ID_SIZE * 2 + 1)
 
 #include "tool.h"
 #include "strlist.h"
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 83c08037e7e2..49fb7b5feb09 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -210,6 +210,7 @@ void perf_evsel__init(struct perf_evsel *evsel,
 	perf_evsel__object.init(evsel);
 	evsel->sample_size = __perf_evsel__sample_size(attr->sample_type);
 	perf_evsel__calc_id_pos(evsel);
+	evsel->cmdline_group_boundary = false;
 }
 
 struct perf_evsel *perf_evsel__new_idx(struct perf_event_attr *attr, int idx)
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index fe9f3279632b..1fc263a80d91 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -86,6 +86,7 @@ struct perf_evsel {
 	unsigned long		*per_pkg_mask;
 	struct perf_evsel	*leader;
 	char			*group_name;
+	bool			cmdline_group_boundary;
 };
 
 union u64_swap {
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 7ff682770fdb..d0bf1e590479 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -250,7 +250,7 @@ struct machine *machines__findnew(struct machines *machines, pid_t pid)
 			static struct strlist *seen;
 
 			if (!seen)
-				seen = strlist__new(true, NULL);
+				seen = strlist__new(NULL, NULL);
 
 			if (!strlist__has_entry(seen, path)) {
 				pr_err("Can't access file %s\n", path);
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index a71eeb279ed2..4f807fc1b14a 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -1065,8 +1065,13 @@ int parse_events(struct perf_evlist *evlist, const char *str,
 	perf_pmu__parse_cleanup();
 	if (!ret) {
 		int entries = data.idx - evlist->nr_entries;
+		struct perf_evsel *last;
+
 		perf_evlist__splice_list_tail(evlist, &data.list, entries);
 		evlist->nr_groups += data.nr_groups;
+		last = perf_evlist__last(evlist);
+		last->cmdline_group_boundary = true;
+
 		return 0;
 	}
 
@@ -1162,29 +1167,93 @@ int parse_events_option(const struct option *opt, const char *str,
 	return ret;
 }
 
-int parse_filter(const struct option *opt, const char *str,
-		 int unset __maybe_unused)
+static int
+foreach_evsel_in_last_glob(struct perf_evlist *evlist,
+			   int (*func)(struct perf_evsel *evsel,
+				       const void *arg),
+			   const void *arg)
 {
-	struct perf_evlist *evlist = *(struct perf_evlist **)opt->value;
 	struct perf_evsel *last = NULL;
+	int err;
 
 	if (evlist->nr_entries > 0)
 		last = perf_evlist__last(evlist);
 
-	if (last == NULL || last->attr.type != PERF_TYPE_TRACEPOINT) {
+	do {
+		err = (*func)(last, arg);
+		if (err)
+			return -1;
+		if (!last)
+			return 0;
+
+		if (last->node.prev == &evlist->entries)
+			return 0;
+		last = list_entry(last->node.prev, struct perf_evsel, node);
+	} while (!last->cmdline_group_boundary);
+
+	return 0;
+}
+
+static int set_filter(struct perf_evsel *evsel, const void *arg)
+{
+	const char *str = arg;
+
+	if (evsel == NULL || evsel->attr.type != PERF_TYPE_TRACEPOINT) {
 		fprintf(stderr,
 			"--filter option should follow a -e tracepoint option\n");
 		return -1;
 	}
 
-	if (perf_evsel__set_filter(last, str) < 0) {
-		fprintf(stderr, "not enough memory to hold filter string\n");
+	if (perf_evsel__append_filter(evsel, "&&", str) < 0) {
+		fprintf(stderr,
+			"not enough memory to hold filter string\n");
 		return -1;
 	}
 
 	return 0;
 }
 
+int parse_filter(const struct option *opt, const char *str,
+		 int unset __maybe_unused)
+{
+	struct perf_evlist *evlist = *(struct perf_evlist **)opt->value;
+
+	return foreach_evsel_in_last_glob(evlist, set_filter,
+					  (const void *)str);
+}
+
+static int add_exclude_perf_filter(struct perf_evsel *evsel,
+				   const void *arg __maybe_unused)
+{
+	char new_filter[64];
+
+	if (evsel == NULL || evsel->attr.type != PERF_TYPE_TRACEPOINT) {
+		fprintf(stderr,
+			"--exclude-perf option should follow a -e tracepoint option\n");
+		return -1;
+	}
+
+	snprintf(new_filter, sizeof(new_filter), "common_pid != %d", getpid());
+
+	if (perf_evsel__append_filter(evsel, "&&", new_filter) < 0) {
+		fprintf(stderr,
+			"not enough memory to hold filter string\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+int exclude_perf(const struct option *opt,
+		 const char *arg __maybe_unused,
+		 int unset __maybe_unused)
+{
+	struct perf_evlist *evlist = *(struct perf_evlist **)opt->value;
+
+	return foreach_evsel_in_last_glob(evlist, add_exclude_perf_filter,
+					  NULL);
+}
+
 static const char * const event_type_descriptors[] = {
 	"Hardware event",
 	"Software event",
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index 131f29b2f132..2063048a4354 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -34,6 +34,7 @@ extern int parse_events(struct perf_evlist *evlist, const char *str,
 			struct parse_events_error *error);
 extern int parse_events_terms(struct list_head *terms, const char *str);
 extern int parse_filter(const struct option *opt, const char *str, int unset);
+extern int exclude_perf(const struct option *opt, const char *arg, int unset);
 
 #define EVENTS_HELP_MAX (128*1024)
 
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 381f23a443c7..fe4941a94a25 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -45,6 +45,7 @@
 #include "trace-event.h"	/* For __maybe_unused */
 #include "probe-event.h"
 #include "probe-finder.h"
+#include "probe-file.h"
 #include "session.h"
 
 #define MAX_CMDLEN 256
@@ -55,11 +56,7 @@ struct probe_conf probe_conf;
 
 #define semantic_error(msg ...) pr_err("Semantic error :" msg)
 
-/* If there is no space to write, returns -E2BIG. */
-static int e_snprintf(char *str, size_t size, const char *format, ...)
-	__attribute__((format(printf, 3, 4)));
-
-static int e_snprintf(char *str, size_t size, const char *format, ...)
+int e_snprintf(char *str, size_t size, const char *format, ...)
 {
 	int ret;
 	va_list ap;
@@ -72,7 +69,6 @@ static int e_snprintf(char *str, size_t size, const char *format, ...)
 }
 
 static char *synthesize_perf_probe_point(struct perf_probe_point *pp);
-static void clear_probe_trace_event(struct probe_trace_event *tev);
 static struct machine *host_machine;
 
 /* Initialize symbol maps and path of vmlinux/modules */
@@ -1467,8 +1463,7 @@ bool perf_probe_event_need_dwarf(struct perf_probe_event *pev)
 }
 
 /* Parse probe_events event into struct probe_point */
-static int parse_probe_trace_command(const char *cmd,
-				     struct probe_trace_event *tev)
+int parse_probe_trace_command(const char *cmd, struct probe_trace_event *tev)
 {
 	struct probe_trace_point *tp = &tev->point;
 	char pr;
@@ -1951,7 +1946,7 @@ void clear_perf_probe_event(struct perf_probe_event *pev)
 	memset(pev, 0, sizeof(*pev));
 }
 
-static void clear_probe_trace_event(struct probe_trace_event *tev)
+void clear_probe_trace_event(struct probe_trace_event *tev)
 {
 	struct probe_trace_arg_ref *ref, *next;
 	int i;
@@ -1976,119 +1971,6 @@ static void clear_probe_trace_event(struct probe_trace_event *tev)
 	memset(tev, 0, sizeof(*tev));
 }
 
-static void print_open_warning(int err, bool is_kprobe)
-{
-	char sbuf[STRERR_BUFSIZE];
-
-	if (err == -ENOENT) {
-		const char *config;
-
-		if (!is_kprobe)
-			config = "CONFIG_UPROBE_EVENTS";
-		else
-			config = "CONFIG_KPROBE_EVENTS";
-
-		pr_warning("%cprobe_events file does not exist"
-			   " - please rebuild kernel with %s.\n",
-			   is_kprobe ? 'k' : 'u', config);
-	} else if (err == -ENOTSUP)
-		pr_warning("Tracefs or debugfs is not mounted.\n");
-	else
-		pr_warning("Failed to open %cprobe_events: %s\n",
-			   is_kprobe ? 'k' : 'u',
-			   strerror_r(-err, sbuf, sizeof(sbuf)));
-}
-
-static void print_both_open_warning(int kerr, int uerr)
-{
-	/* Both kprobes and uprobes are disabled, warn it. */
-	if (kerr == -ENOTSUP && uerr == -ENOTSUP)
-		pr_warning("Tracefs or debugfs is not mounted.\n");
-	else if (kerr == -ENOENT && uerr == -ENOENT)
-		pr_warning("Please rebuild kernel with CONFIG_KPROBE_EVENTS "
-			   "or/and CONFIG_UPROBE_EVENTS.\n");
-	else {
-		char sbuf[STRERR_BUFSIZE];
-		pr_warning("Failed to open kprobe events: %s.\n",
-			   strerror_r(-kerr, sbuf, sizeof(sbuf)));
-		pr_warning("Failed to open uprobe events: %s.\n",
-			   strerror_r(-uerr, sbuf, sizeof(sbuf)));
-	}
-}
-
-static int open_probe_events(const char *trace_file, bool readwrite)
-{
-	char buf[PATH_MAX];
-	const char *__debugfs;
-	const char *tracing_dir = "";
-	int ret;
-
-	__debugfs = tracefs_find_mountpoint();
-	if (__debugfs == NULL) {
-		tracing_dir = "tracing/";
-
-		__debugfs = debugfs_find_mountpoint();
-		if (__debugfs == NULL)
-			return -ENOTSUP;
-	}
-
-	ret = e_snprintf(buf, PATH_MAX, "%s/%s%s",
-			 __debugfs, tracing_dir, trace_file);
-	if (ret >= 0) {
-		pr_debug("Opening %s write=%d\n", buf, readwrite);
-		if (readwrite && !probe_event_dry_run)
-			ret = open(buf, O_RDWR | O_APPEND, 0);
-		else
-			ret = open(buf, O_RDONLY, 0);
-
-		if (ret < 0)
-			ret = -errno;
-	}
-	return ret;
-}
-
-static int open_kprobe_events(bool readwrite)
-{
-	return open_probe_events("kprobe_events", readwrite);
-}
-
-static int open_uprobe_events(bool readwrite)
-{
-	return open_probe_events("uprobe_events", readwrite);
-}
-
-/* Get raw string list of current kprobe_events  or uprobe_events */
-static struct strlist *get_probe_trace_command_rawlist(int fd)
-{
-	int ret, idx;
-	FILE *fp;
-	char buf[MAX_CMDLEN];
-	char *p;
-	struct strlist *sl;
-
-	sl = strlist__new(true, NULL);
-
-	fp = fdopen(dup(fd), "r");
-	while (!feof(fp)) {
-		p = fgets(buf, MAX_CMDLEN, fp);
-		if (!p)
-			break;
-
-		idx = strlen(p) - 1;
-		if (p[idx] == '\n')
-			p[idx] = '\0';
-		ret = strlist__add(sl, buf);
-		if (ret < 0) {
-			pr_debug("strlist__add failed (%d)\n", ret);
-			strlist__delete(sl);
-			return NULL;
-		}
-	}
-	fclose(fp);
-
-	return sl;
-}
-
 struct kprobe_blacklist_node {
 	struct list_head list;
 	unsigned long start;
@@ -2284,7 +2166,7 @@ static int __show_perf_probe_events(int fd, bool is_kprobe,
 	memset(&tev, 0, sizeof(tev));
 	memset(&pev, 0, sizeof(pev));
 
-	rawlist = get_probe_trace_command_rawlist(fd);
+	rawlist = probe_file__get_rawlist(fd);
 	if (!rawlist)
 		return -ENOMEM;
 
@@ -2325,89 +2207,20 @@ int show_perf_probe_events(struct strfilter *filter)
 	if (ret < 0)
 		return ret;
 
-	kp_fd = open_kprobe_events(false);
-	if (kp_fd >= 0) {
-		ret = __show_perf_probe_events(kp_fd, true, filter);
-		close(kp_fd);
-		if (ret < 0)
-			goto out;
-	}
-
-	up_fd = open_uprobe_events(false);
-	if (kp_fd < 0 && up_fd < 0) {
-		print_both_open_warning(kp_fd, up_fd);
-		ret = kp_fd;
-		goto out;
-	}
+	ret = probe_file__open_both(&kp_fd, &up_fd, 0);
+	if (ret < 0)
+		return ret;
 
-	if (up_fd >= 0) {
+	if (kp_fd >= 0)
+		ret = __show_perf_probe_events(kp_fd, true, filter);
+	if (up_fd >= 0 && ret >= 0)
 		ret = __show_perf_probe_events(up_fd, false, filter);
+	if (kp_fd > 0)
+		close(kp_fd);
+	if (up_fd > 0)
 		close(up_fd);
-	}
-out:
 	exit_symbol_maps();
-	return ret;
-}
-
-/* Get current perf-probe event names */
-static struct strlist *get_probe_trace_event_names(int fd, bool include_group)
-{
-	char buf[128];
-	struct strlist *sl, *rawlist;
-	struct str_node *ent;
-	struct probe_trace_event tev;
-	int ret = 0;
-
-	memset(&tev, 0, sizeof(tev));
-	rawlist = get_probe_trace_command_rawlist(fd);
-	if (!rawlist)
-		return NULL;
-	sl = strlist__new(true, NULL);
-	strlist__for_each(ent, rawlist) {
-		ret = parse_probe_trace_command(ent->s, &tev);
-		if (ret < 0)
-			break;
-		if (include_group) {
-			ret = e_snprintf(buf, 128, "%s:%s", tev.group,
-					tev.event);
-			if (ret >= 0)
-				ret = strlist__add(sl, buf);
-		} else
-			ret = strlist__add(sl, tev.event);
-		clear_probe_trace_event(&tev);
-		if (ret < 0)
-			break;
-	}
-	strlist__delete(rawlist);
-
-	if (ret < 0) {
-		strlist__delete(sl);
-		return NULL;
-	}
-	return sl;
-}
-
-static int write_probe_trace_event(int fd, struct probe_trace_event *tev)
-{
-	int ret = 0;
-	char *buf = synthesize_probe_trace_command(tev);
-	char sbuf[STRERR_BUFSIZE];
-
-	if (!buf) {
-		pr_debug("Failed to synthesize probe trace event.\n");
-		return -EINVAL;
-	}
 
-	pr_debug("Writing event: %s\n", buf);
-	if (!probe_event_dry_run) {
-		ret = write(fd, buf, strlen(buf));
-		if (ret <= 0) {
-			ret = -errno;
-			pr_warning("Failed to write event: %s\n",
-				   strerror_r(errno, sbuf, sizeof(sbuf)));
-		}
-	}
-	free(buf);
 	return ret;
 }
 
@@ -2478,36 +2291,67 @@ out:
 	free(buf);
 }
 
+/* Set new name from original perf_probe_event and namelist */
+static int probe_trace_event__set_name(struct probe_trace_event *tev,
+				       struct perf_probe_event *pev,
+				       struct strlist *namelist,
+				       bool allow_suffix)
+{
+	const char *event, *group;
+	char buf[64];
+	int ret;
+
+	if (pev->event)
+		event = pev->event;
+	else
+		if (pev->point.function && !strisglob(pev->point.function))
+			event = pev->point.function;
+		else
+			event = tev->point.realname;
+	if (pev->group)
+		group = pev->group;
+	else
+		group = PERFPROBE_GROUP;
+
+	/* Get an unused new event name */
+	ret = get_new_event_name(buf, 64, event,
+				 namelist, allow_suffix);
+	if (ret < 0)
+		return ret;
+
+	event = buf;
+
+	tev->event = strdup(event);
+	tev->group = strdup(group);
+	if (tev->event == NULL || tev->group == NULL)
+		return -ENOMEM;
+
+	/* Add added event name to namelist */
+	strlist__add(namelist, event);
+	return 0;
+}
+
 static int __add_probe_trace_events(struct perf_probe_event *pev,
 				     struct probe_trace_event *tevs,
 				     int ntevs, bool allow_suffix)
 {
 	int i, fd, ret;
 	struct probe_trace_event *tev = NULL;
-	char buf[64];
 	const char *event = NULL, *group = NULL;
 	struct strlist *namelist;
-	bool safename;
-
-	if (pev->uprobes)
-		fd = open_uprobe_events(true);
-	else
-		fd = open_kprobe_events(true);
 
-	if (fd < 0) {
-		print_open_warning(fd, !pev->uprobes);
+	fd = probe_file__open(PF_FL_RW | (pev->uprobes ? PF_FL_UPROBE : 0));
+	if (fd < 0)
 		return fd;
-	}
 
 	/* Get current event names */
-	namelist = get_probe_trace_event_names(fd, false);
+	namelist = probe_file__get_namelist(fd);
 	if (!namelist) {
 		pr_debug("Failed to get current event list.\n");
 		ret = -ENOMEM;
 		goto close_out;
 	}
 
-	safename = (pev->point.function && !strisglob(pev->point.function));
 	ret = 0;
 	pr_info("Added new event%s\n", (ntevs > 1) ? "s:" : ":");
 	for (i = 0; i < ntevs; i++) {
@@ -2516,36 +2360,15 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,
 		if (!tev->point.symbol)
 			continue;
 
-		if (pev->event)
-			event = pev->event;
-		else
-			if (safename)
-				event = pev->point.function;
-			else
-				event = tev->point.realname;
-		if (pev->group)
-			group = pev->group;
-		else
-			group = PERFPROBE_GROUP;
-
-		/* Get an unused new event name */
-		ret = get_new_event_name(buf, 64, event,
-					 namelist, allow_suffix);
+		/* Set new name for tev (and update namelist) */
+		ret = probe_trace_event__set_name(tev, pev, namelist,
+						  allow_suffix);
 		if (ret < 0)
 			break;
-		event = buf;
 
-		tev->event = strdup(event);
-		tev->group = strdup(group);
-		if (tev->event == NULL || tev->group == NULL) {
-			ret = -ENOMEM;
-			break;
-		}
-		ret = write_probe_trace_event(fd, tev);
+		ret = probe_file__add_event(fd, tev);
 		if (ret < 0)
 			break;
-		/* Add added event name to namelist */
-		strlist__add(namelist, event);
 
 		/* We use tev's name for showing new events */
 		show_perf_probe_event(tev->group, tev->event, pev,
@@ -2838,68 +2661,9 @@ end:
 	return ret;
 }
 
-static int __del_trace_probe_event(int fd, struct str_node *ent)
-{
-	char *p;
-	char buf[128];
-	int ret;
-
-	/* Convert from perf-probe event to trace-probe event */
-	ret = e_snprintf(buf, 128, "-:%s", ent->s);
-	if (ret < 0)
-		goto error;
-
-	p = strchr(buf + 2, ':');
-	if (!p) {
-		pr_debug("Internal error: %s should have ':' but not.\n",
-			 ent->s);
-		ret = -ENOTSUP;
-		goto error;
-	}
-	*p = '/';
-
-	pr_debug("Writing event: %s\n", buf);
-	ret = write(fd, buf, strlen(buf));
-	if (ret < 0) {
-		ret = -errno;
-		goto error;
-	}
-
-	pr_info("Removed event: %s\n", ent->s);
-	return 0;
-error:
-	pr_warning("Failed to delete event: %s\n",
-		   strerror_r(-ret, buf, sizeof(buf)));
-	return ret;
-}
-
-static int del_trace_probe_events(int fd, struct strfilter *filter,
-				  struct strlist *namelist)
-{
-	struct str_node *ent;
-	const char *p;
-	int ret = -ENOENT;
-
-	if (!namelist)
-		return -ENOENT;
-
-	strlist__for_each(ent, namelist) {
-		p = strchr(ent->s, ':');
-		if ((p && strfilter__compare(filter, p + 1)) ||
-		    strfilter__compare(filter, ent->s)) {
-			ret = __del_trace_probe_event(fd, ent);
-			if (ret < 0)
-				break;
-		}
-	}
-
-	return ret;
-}
-
 int del_perf_probe_events(struct strfilter *filter)
 {
 	int ret, ret2, ufd = -1, kfd = -1;
-	struct strlist *namelist = NULL, *unamelist = NULL;
 	char *str = strfilter__string(filter);
 
 	if (!str)
@@ -2908,25 +2672,15 @@ int del_perf_probe_events(struct strfilter *filter)
 	pr_debug("Delete filter: \'%s\'\n", str);
 
 	/* Get current event names */
-	kfd = open_kprobe_events(true);
-	if (kfd >= 0)
-		namelist = get_probe_trace_event_names(kfd, true);
-
-	ufd = open_uprobe_events(true);
-	if (ufd >= 0)
-		unamelist = get_probe_trace_event_names(ufd, true);
-
-	if (kfd < 0 && ufd < 0) {
-		print_both_open_warning(kfd, ufd);
-		ret = kfd;
-		goto error;
-	}
+	ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
+	if (ret < 0)
+		goto out;
 
-	ret = del_trace_probe_events(kfd, filter, namelist);
+	ret = probe_file__del_events(kfd, filter);
 	if (ret < 0 && ret != -ENOENT)
 		goto error;
 
-	ret2 = del_trace_probe_events(ufd, filter, unamelist);
+	ret2 = probe_file__del_events(ufd, filter);
 	if (ret2 < 0 && ret2 != -ENOENT) {
 		ret = ret2;
 		goto error;
@@ -2937,15 +2691,11 @@ int del_perf_probe_events(struct strfilter *filter)
 	ret = 0;
 
 error:
-	if (kfd >= 0) {
-		strlist__delete(namelist);
+	if (kfd >= 0)
 		close(kfd);
-	}
-
-	if (ufd >= 0) {
-		strlist__delete(unamelist);
+	if (ufd >= 0)
 		close(ufd);
-	}
+out:
 	free(str);
 
 	return ret;
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index 31db6ee7db54..20f555d1ae1c 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -109,6 +109,8 @@ struct variable_list {
 /* Command string to events */
 extern int parse_perf_probe_command(const char *cmd,
 				    struct perf_probe_event *pev);
+extern int parse_probe_trace_command(const char *cmd,
+				     struct probe_trace_event *tev);
 
 /* Events to command string */
 extern char *synthesize_perf_probe_command(struct perf_probe_event *pev);
@@ -121,6 +123,7 @@ extern bool perf_probe_event_need_dwarf(struct perf_probe_event *pev);
 
 /* Release event contents */
 extern void clear_perf_probe_event(struct perf_probe_event *pev);
+extern void clear_probe_trace_event(struct probe_trace_event *tev);
 
 /* Command string to line-range */
 extern int parse_line_range_desc(const char *cmd, struct line_range *lr);
@@ -144,6 +147,10 @@ bool arch__prefers_symtab(void);
 void arch__fix_tev_from_maps(struct perf_probe_event *pev,
 			     struct probe_trace_event *tev, struct map *map);
 
+/* If there is no space to write, returns -E2BIG. */
+int e_snprintf(char *str, size_t size, const char *format, ...)
+	__attribute__((format(printf, 3, 4)));
+
 /* Maximum index number of event-name postfix */
 #define MAX_EVENT_INDEX	1024
 
diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
new file mode 100644
index 000000000000..bbb243717ec8
--- /dev/null
+++ b/tools/perf/util/probe-file.c
@@ -0,0 +1,301 @@
+/*
+ * probe-file.c : operate ftrace k/uprobe events files
+ *
+ * Written by Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+#include "util.h"
+#include "event.h"
+#include "strlist.h"
+#include "debug.h"
+#include "cache.h"
+#include "color.h"
+#include "symbol.h"
+#include "thread.h"
+#include <api/fs/debugfs.h>
+#include <api/fs/tracefs.h>
+#include "probe-event.h"
+#include "probe-file.h"
+#include "session.h"
+
+#define MAX_CMDLEN 256
+
+static void print_open_warning(int err, bool uprobe)
+{
+	char sbuf[STRERR_BUFSIZE];
+
+	if (err == -ENOENT) {
+		const char *config;
+
+		if (uprobe)
+			config = "CONFIG_UPROBE_EVENTS";
+		else
+			config = "CONFIG_KPROBE_EVENTS";
+
+		pr_warning("%cprobe_events file does not exist"
+			   " - please rebuild kernel with %s.\n",
+			   uprobe ? 'u' : 'k', config);
+	} else if (err == -ENOTSUP)
+		pr_warning("Tracefs or debugfs is not mounted.\n");
+	else
+		pr_warning("Failed to open %cprobe_events: %s\n",
+			   uprobe ? 'u' : 'k',
+			   strerror_r(-err, sbuf, sizeof(sbuf)));
+}
+
+static void print_both_open_warning(int kerr, int uerr)
+{
+	/* Both kprobes and uprobes are disabled, warn it. */
+	if (kerr == -ENOTSUP && uerr == -ENOTSUP)
+		pr_warning("Tracefs or debugfs is not mounted.\n");
+	else if (kerr == -ENOENT && uerr == -ENOENT)
+		pr_warning("Please rebuild kernel with CONFIG_KPROBE_EVENTS "
+			   "or/and CONFIG_UPROBE_EVENTS.\n");
+	else {
+		char sbuf[STRERR_BUFSIZE];
+		pr_warning("Failed to open kprobe events: %s.\n",
+			   strerror_r(-kerr, sbuf, sizeof(sbuf)));
+		pr_warning("Failed to open uprobe events: %s.\n",
+			   strerror_r(-uerr, sbuf, sizeof(sbuf)));
+	}
+}
+
+static int open_probe_events(const char *trace_file, bool readwrite)
+{
+	char buf[PATH_MAX];
+	const char *__debugfs;
+	const char *tracing_dir = "";
+	int ret;
+
+	__debugfs = tracefs_find_mountpoint();
+	if (__debugfs == NULL) {
+		tracing_dir = "tracing/";
+
+		__debugfs = debugfs_find_mountpoint();
+		if (__debugfs == NULL)
+			return -ENOTSUP;
+	}
+
+	ret = e_snprintf(buf, PATH_MAX, "%s/%s%s",
+			 __debugfs, tracing_dir, trace_file);
+	if (ret >= 0) {
+		pr_debug("Opening %s write=%d\n", buf, readwrite);
+		if (readwrite && !probe_event_dry_run)
+			ret = open(buf, O_RDWR | O_APPEND, 0);
+		else
+			ret = open(buf, O_RDONLY, 0);
+
+		if (ret < 0)
+			ret = -errno;
+	}
+	return ret;
+}
+
+static int open_kprobe_events(bool readwrite)
+{
+	return open_probe_events("kprobe_events", readwrite);
+}
+
+static int open_uprobe_events(bool readwrite)
+{
+	return open_probe_events("uprobe_events", readwrite);
+}
+
+int probe_file__open(int flag)
+{
+	int fd;
+
+	if (flag & PF_FL_UPROBE)
+		fd = open_uprobe_events(flag & PF_FL_RW);
+	else
+		fd = open_kprobe_events(flag & PF_FL_RW);
+	if (fd < 0)
+		print_open_warning(fd, flag & PF_FL_UPROBE);
+
+	return fd;
+}
+
+int probe_file__open_both(int *kfd, int *ufd, int flag)
+{
+	if (!kfd || !ufd)
+		return -EINVAL;
+
+	*kfd = open_kprobe_events(flag & PF_FL_RW);
+	*ufd = open_uprobe_events(flag & PF_FL_RW);
+	if (*kfd < 0 && *ufd < 0) {
+		print_both_open_warning(*kfd, *ufd);
+		return *kfd;
+	}
+
+	return 0;
+}
+
+/* Get raw string list of current kprobe_events  or uprobe_events */
+struct strlist *probe_file__get_rawlist(int fd)
+{
+	int ret, idx;
+	FILE *fp;
+	char buf[MAX_CMDLEN];
+	char *p;
+	struct strlist *sl;
+
+	sl = strlist__new(NULL, NULL);
+
+	fp = fdopen(dup(fd), "r");
+	while (!feof(fp)) {
+		p = fgets(buf, MAX_CMDLEN, fp);
+		if (!p)
+			break;
+
+		idx = strlen(p) - 1;
+		if (p[idx] == '\n')
+			p[idx] = '\0';
+		ret = strlist__add(sl, buf);
+		if (ret < 0) {
+			pr_debug("strlist__add failed (%d)\n", ret);
+			strlist__delete(sl);
+			return NULL;
+		}
+	}
+	fclose(fp);
+
+	return sl;
+}
+
+static struct strlist *__probe_file__get_namelist(int fd, bool include_group)
+{
+	char buf[128];
+	struct strlist *sl, *rawlist;
+	struct str_node *ent;
+	struct probe_trace_event tev;
+	int ret = 0;
+
+	memset(&tev, 0, sizeof(tev));
+	rawlist = probe_file__get_rawlist(fd);
+	if (!rawlist)
+		return NULL;
+	sl = strlist__new(NULL, NULL);
+	strlist__for_each(ent, rawlist) {
+		ret = parse_probe_trace_command(ent->s, &tev);
+		if (ret < 0)
+			break;
+		if (include_group) {
+			ret = e_snprintf(buf, 128, "%s:%s", tev.group,
+					tev.event);
+			if (ret >= 0)
+				ret = strlist__add(sl, buf);
+		} else
+			ret = strlist__add(sl, tev.event);
+		clear_probe_trace_event(&tev);
+		if (ret < 0)
+			break;
+	}
+	strlist__delete(rawlist);
+
+	if (ret < 0) {
+		strlist__delete(sl);
+		return NULL;
+	}
+	return sl;
+}
+
+/* Get current perf-probe event names */
+struct strlist *probe_file__get_namelist(int fd)
+{
+	return __probe_file__get_namelist(fd, false);
+}
+
+int probe_file__add_event(int fd, struct probe_trace_event *tev)
+{
+	int ret = 0;
+	char *buf = synthesize_probe_trace_command(tev);
+	char sbuf[STRERR_BUFSIZE];
+
+	if (!buf) {
+		pr_debug("Failed to synthesize probe trace event.\n");
+		return -EINVAL;
+	}
+
+	pr_debug("Writing event: %s\n", buf);
+	if (!probe_event_dry_run) {
+		ret = write(fd, buf, strlen(buf));
+		if (ret <= 0) {
+			ret = -errno;
+			pr_warning("Failed to write event: %s\n",
+				   strerror_r(errno, sbuf, sizeof(sbuf)));
+		}
+	}
+	free(buf);
+
+	return ret;
+}
+
+static int __del_trace_probe_event(int fd, struct str_node *ent)
+{
+	char *p;
+	char buf[128];
+	int ret;
+
+	/* Convert from perf-probe event to trace-probe event */
+	ret = e_snprintf(buf, 128, "-:%s", ent->s);
+	if (ret < 0)
+		goto error;
+
+	p = strchr(buf + 2, ':');
+	if (!p) {
+		pr_debug("Internal error: %s should have ':' but not.\n",
+			 ent->s);
+		ret = -ENOTSUP;
+		goto error;
+	}
+	*p = '/';
+
+	pr_debug("Writing event: %s\n", buf);
+	ret = write(fd, buf, strlen(buf));
+	if (ret < 0) {
+		ret = -errno;
+		goto error;
+	}
+
+	pr_info("Removed event: %s\n", ent->s);
+	return 0;
+error:
+	pr_warning("Failed to delete event: %s\n",
+		   strerror_r(-ret, buf, sizeof(buf)));
+	return ret;
+}
+
+int probe_file__del_events(int fd, struct strfilter *filter)
+{
+	struct strlist *namelist;
+	struct str_node *ent;
+	const char *p;
+	int ret = -ENOENT;
+
+	namelist = __probe_file__get_namelist(fd, true);
+	if (!namelist)
+		return -ENOENT;
+
+	strlist__for_each(ent, namelist) {
+		p = strchr(ent->s, ':');
+		if ((p && strfilter__compare(filter, p + 1)) ||
+		    strfilter__compare(filter, ent->s)) {
+			ret = __del_trace_probe_event(fd, ent);
+			if (ret < 0)
+				break;
+		}
+	}
+	strlist__delete(namelist);
+
+	return ret;
+}
diff --git a/tools/perf/util/probe-file.h b/tools/perf/util/probe-file.h
new file mode 100644
index 000000000000..ada94a242a17
--- /dev/null
+++ b/tools/perf/util/probe-file.h
@@ -0,0 +1,18 @@
+#ifndef __PROBE_FILE_H
+#define __PROBE_FILE_H
+
+#include "strlist.h"
+#include "strfilter.h"
+#include "probe-event.h"
+
+#define PF_FL_UPROBE	1
+#define PF_FL_RW	2
+
+int probe_file__open(int flag);
+int probe_file__open_both(int *kfd, int *ufd, int flag);
+struct strlist *probe_file__get_namelist(int fd);
+struct strlist *probe_file__get_rawlist(int fd);
+int probe_file__add_event(int fd, struct probe_trace_event *tev);
+int probe_file__del_events(int fd, struct strfilter *filter);
+
+#endif
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 2da65a710893..7b80f8cb62b9 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -1355,7 +1355,7 @@ static int add_available_vars(Dwarf_Die *sc_die, struct probe_finder *pf)
 		 vl->point.offset);
 
 	/* Find local variables */
-	vl->vars = strlist__new(true, NULL);
+	vl->vars = strlist__new(NULL, NULL);
 	if (vl->vars == NULL)
 		return -ENOMEM;
 	af->child = true;
diff --git a/tools/perf/util/strlist.c b/tools/perf/util/strlist.c
index 71f9d102b96f..bdf98f6f27bb 100644
--- a/tools/perf/util/strlist.c
+++ b/tools/perf/util/strlist.c
@@ -72,7 +72,7 @@ int strlist__load(struct strlist *slist, const char *filename)
 	FILE *fp = fopen(filename, "r");
 
 	if (fp == NULL)
-		return errno;
+		return -errno;
 
 	while (fgets(entry, sizeof(entry), fp) != NULL) {
 		const size_t len = strlen(entry);
@@ -108,43 +108,70 @@ struct str_node *strlist__find(struct strlist *slist, const char *entry)
 	return snode;
 }
 
-static int strlist__parse_list_entry(struct strlist *slist, const char *s)
+static int strlist__parse_list_entry(struct strlist *slist, const char *s,
+				     const char *subst_dir)
 {
+	int err;
+	char *subst = NULL;
+
 	if (strncmp(s, "file://", 7) == 0)
 		return strlist__load(slist, s + 7);
 
-	return strlist__add(slist, s);
+	if (subst_dir) {
+		err = -ENOMEM;
+		if (asprintf(&subst, "%s/%s", subst_dir, s) < 0)
+			goto out;
+
+		if (access(subst, F_OK) == 0) {
+			err = strlist__load(slist, subst);
+			goto out;
+		}
+	}
+
+	err = strlist__add(slist, s);
+out:
+	free(subst);
+	return err;
 }
 
-int strlist__parse_list(struct strlist *slist, const char *s)
+static int strlist__parse_list(struct strlist *slist, const char *s, const char *subst_dir)
 {
 	char *sep;
 	int err;
 
 	while ((sep = strchr(s, ',')) != NULL) {
 		*sep = '\0';
-		err = strlist__parse_list_entry(slist, s);
+		err = strlist__parse_list_entry(slist, s, subst_dir);
 		*sep = ',';
 		if (err != 0)
 			return err;
 		s = sep + 1;
 	}
 
-	return *s ? strlist__parse_list_entry(slist, s) : 0;
+	return *s ? strlist__parse_list_entry(slist, s, subst_dir) : 0;
 }
 
-struct strlist *strlist__new(bool dupstr, const char *list)
+struct strlist *strlist__new(const char *list, const struct strlist_config *config)
 {
 	struct strlist *slist = malloc(sizeof(*slist));
 
 	if (slist != NULL) {
+		bool dupstr = true;
+		const char *dirname = NULL;
+
+		if (config) {
+			dupstr = !config->dont_dupstr;
+			dirname = config->dirname;
+		}
+
 		rblist__init(&slist->rblist);
 		slist->rblist.node_cmp    = strlist__node_cmp;
 		slist->rblist.node_new    = strlist__node_new;
 		slist->rblist.node_delete = strlist__node_delete;
 
 		slist->dupstr	 = dupstr;
-		if (list && strlist__parse_list(slist, list) != 0)
+
+		if (list && strlist__parse_list(slist, list, dirname) != 0)
 			goto out_error;
 	}
 
diff --git a/tools/perf/util/strlist.h b/tools/perf/util/strlist.h
index 5c7f87069d9c..297565aa7535 100644
--- a/tools/perf/util/strlist.h
+++ b/tools/perf/util/strlist.h
@@ -16,7 +16,12 @@ struct strlist {
 	bool	       dupstr;
 };
 
-struct strlist *strlist__new(bool dupstr, const char *slist);
+struct strlist_config {
+	bool dont_dupstr;
+	const char *dirname;
+};
+
+struct strlist *strlist__new(const char *slist, const struct strlist_config *config);
 void strlist__delete(struct strlist *slist);
 
 void strlist__remove(struct strlist *slist, struct str_node *sn);
@@ -74,6 +79,4 @@ static inline struct str_node *strlist__next(struct str_node *sn)
 #define strlist__for_each_safe(pos, n, slist)	\
 	for (pos = strlist__first(slist), n = strlist__next(pos); pos;\
 	     pos = n, n = strlist__next(n))
-
-int strlist__parse_list(struct strlist *slist, const char *s);
 #endif /* __PERF_STRLIST_H */
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 60f11414bb5c..45c2e3a8316b 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1906,7 +1906,7 @@ int setup_list(struct strlist **list, const char *list_str,
 	if (list_str == NULL)
 		return 0;
 
-	*list = strlist__new(true, list_str);
+	*list = strlist__new(list_str, NULL);
 	if (!*list) {
 		pr_err("problems parsing %s list\n", list_name);
 		return -1;
diff --git a/tools/perf/util/thread_map.c b/tools/perf/util/thread_map.c
index 292ae2c90e06..6ec3c5ca438f 100644
--- a/tools/perf/util/thread_map.c
+++ b/tools/perf/util/thread_map.c
@@ -195,7 +195,8 @@ static struct thread_map *thread_map__new_by_pid_str(const char *pid_str)
 	pid_t pid, prev_pid = INT_MAX;
 	char *end_ptr;
 	struct str_node *pos;
-	struct strlist *slist = strlist__new(false, pid_str);
+	struct strlist_config slist_config = { .dont_dupstr = true, };
+	struct strlist *slist = strlist__new(pid_str, &slist_config);
 
 	if (!slist)
 		return NULL;
@@ -265,13 +266,14 @@ static struct thread_map *thread_map__new_by_tid_str(const char *tid_str)
 	pid_t tid, prev_tid = INT_MAX;
 	char *end_ptr;
 	struct str_node *pos;
+	struct strlist_config slist_config = { .dont_dupstr = true, };
 	struct strlist *slist;
 
 	/* perf-stat expects threads to be generated even if tid not given */
 	if (!tid_str)
 		return thread_map__new_dummy();
 
-	slist = strlist__new(false, tid_str);
+	slist = strlist__new(tid_str, &slist_config);
 	if (!slist)
 		return NULL;