[RFC PATCH perf/core 00/13] perf-probe --cache support

[RFC PATCH perf/core 00/13] perf-probe --cache support

[Masami Hiramatsu]

Hi,

Here is a patches for probe-cache which is going to be perf-cache
finally, but I'd like to implement prototype on perf-probe. So,
this version is still not ready to be merged.

The perf-probe is useful for debugging, but it strongly depends
on the debuginfo. Without debuginfo, it is just a frontend of
ftrace's dynamic events. This can usually happen in server
farms or on cloud system, since no one wants to distribute
big debuginfo packages.

To solve this issue, I had tried to make a pre-analyzed probes
( https://lkml.org/lkml/2014/10/31/207 ) but it has a problm
that we can't ensure the probed binary is same as what we analyzed.
Arnaldo gave me an idea to reuse build-id cache for that perpose
and this series is the first prototype of that.

At the same time, Hemant has started to support SDT probes which
also use the cache file of SDT info. So I decided to merge this
into the same build-id cache. In this version, I couldn't get it
done... it still needs a bit more patches. I'll do that in the
next version.

In this version, perf probe supports --cache option which means
that perf probe manipulate probe caches, for example,

  perf probe --cache --add "probe-desc"

does not only add probe events but also add "probe-desc" and
it's result on the cache. (Note that the cached entry is always
referred even without --cache)
The --list and --del commands also support --cache. Note that
both are only manipulate caches, not real events.

Thank you,

---

Masami Hiramatsu (13):
      perf-buildid-cache: Use path/to/bin/buildid/elf instead of path/to/bin/buildid
      perf probe: Simplify __add_probe_trace_events code
      perf probe: Move ftrace probe-event operations to probe-file.c
      perf buildid: Use SBUILD_ID_SIZE macro
      perf buildid: Introduce sysfs/filename__sprintf_build_id
      perf: Add lsdir to read a directory
      perf-buildid-cache: Use lsdir for looking up buildid caches
      perf probe: Check kprobe blacklist in converting phase
      perf probe: Use strbuf for making strings in probe-event.c
      perf probe: Add --cache option to cache the probe definitions
      perf probe: Use cache entry if possible
      perf probe: Show all cached probes
      perf probe: Remove caches when --cache is given


 tools/perf/builtin-buildid-cache.c |   22 -
 tools/perf/builtin-buildid-list.c  |   28 -
 tools/perf/builtin-probe.c         |    3 
 tools/perf/util/Build              |    1 
 tools/perf/util/build-id.c         |  203 ++++++--
 tools/perf/util/build-id.h         |   11 
 tools/perf/util/dso.h              |    5 
 tools/perf/util/probe-event.c      |  927 +++++++++++++++---------------------
 tools/perf/util/probe-event.h      |   15 +
 tools/perf/util/probe-file.c       |  694 +++++++++++++++++++++++++++
 tools/perf/util/probe-file.h       |   44 ++
 tools/perf/util/probe-finder.c     |   10 
 tools/perf/util/symbol.c           |    2 
 tools/perf/util/util.c             |   34 +
 tools/perf/util/util.h             |    4 
 15 files changed, 1386 insertions(+), 617 deletions(-)
 create mode 100644 tools/perf/util/probe-file.c
 create mode 100644 tools/perf/util/probe-file.h


-- 
Masami HIRAMATSU
Linux Technology Research Center, System Productivity Research Dept.
Center for Technology Innovation - Systems Engineering 
Hitachi, Ltd., Research & Development Group
E-mail: masami.hiramatsu.pt@hitachi.com

[RFC PATCH perf/core 01/13] perf-buildid-cache: Use path/to/bin/buildid/elf instead of path/to/bin/buildid

[Masami Hiramatsu]

Use path/to/bin/buildid/elf instead of path/to/bin/buildid
to store corresponding elf binary.
This also stores vdso in buildid/vdso, kallsyms in buildid/kallsyms.
Note that the build-id based symlink changes to point to the
path/to/bin/buildid, not path/to/bin/buildid/elf.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/util/build-id.c |   61 ++++++++++++++++++++++++++++++++------------
 tools/perf/util/dso.h      |    5 ++++
 tools/perf/util/symbol.c   |    2 +
 3 files changed, 50 insertions(+), 18 deletions(-)

diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
index 1f6fc23..204d23d 100644
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -112,7 +112,8 @@ static int asnprintf(char **strp, size_t size, const char *fmt, ...)
 	return ret;
 }
 
-static char *build_id__filename(const char *sbuild_id, char *bf, size_t size)
+static char *build_id_cache__linkname(const char *sbuild_id, char *bf,
+				      size_t size)
 {
 	char *tmp = bf;
 	int ret = asnprintf(&bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
@@ -122,15 +123,35 @@ static char *build_id__filename(const char *sbuild_id, char *bf, size_t size)
 	return bf;
 }
 
+static const char *build_id_cache__basename(bool is_kallsyms, bool is_vdso)
+{
+	return is_kallsyms ? "kallsyms" : (is_vdso ? "vdso" : "elf");
+}
+
 char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size)
 {
+	bool is_kallsyms = dso__is_kallsyms((struct dso *)dso);
+	bool is_vdso = dso__is_vdso((struct dso *)dso);
 	char build_id_hex[BUILD_ID_SIZE * 2 + 1];
+	char *linkname;
+	bool alloc = (bf == NULL);
+	int ret;
 
 	if (!dso->has_build_id)
 		return NULL;
 
 	build_id__sprintf(dso->build_id, sizeof(dso->build_id), build_id_hex);
-	return build_id__filename(build_id_hex, bf, size);
+	linkname = build_id_cache__linkname(build_id_hex, NULL, 0);
+	if (!linkname)
+		return NULL;
+
+	ret = asnprintf(&bf, size, "%s/%s", linkname,
+			 build_id_cache__basename(is_kallsyms, is_vdso));
+	if (ret < 0 || (!alloc && size < (unsigned int)ret))
+		bf = NULL;
+	free(linkname);
+
+	return bf;
 }
 
 #define dsos__for_each_with_build_id(pos, head)	\
@@ -261,7 +282,8 @@ void disable_buildid_cache(void)
 }
 
 static char *build_id_cache__dirname_from_path(const char *name,
-					       bool is_kallsyms, bool is_vdso)
+					       bool is_kallsyms, bool is_vdso,
+					       const char *sbuild_id)
 {
 	char *realname = (char *)name, *filename;
 	bool slash = is_kallsyms || is_vdso;
@@ -272,8 +294,9 @@ static char *build_id_cache__dirname_from_path(const char *name,
 			return NULL;
 	}
 
-	if (asprintf(&filename, "%s%s%s", buildid_dir, slash ? "/" : "",
-		     is_vdso ? DSO__NAME_VDSO : realname) < 0)
+	if (asprintf(&filename, "%s%s%s%s%s", buildid_dir, slash ? "/" : "",
+		     is_vdso ? DSO__NAME_VDSO : realname,
+		     sbuild_id ? "/" : "", sbuild_id ?: "") < 0)
 		filename = NULL;
 
 	if (!slash)
@@ -292,7 +315,8 @@ int build_id_cache__list_build_ids(const char *pathname,
 	int ret = 0;
 
 	list = strlist__new(true, NULL);
-	dir_name = build_id_cache__dirname_from_path(pathname, false, false);
+	dir_name = build_id_cache__dirname_from_path(pathname, false, false,
+						     NULL);
 	if (!list || !dir_name) {
 		ret = -ENOMEM;
 		goto out;
@@ -327,7 +351,7 @@ int build_id_cache__add_s(const char *sbuild_id, const char *name,
 {
 	const size_t size = PATH_MAX;
 	char *realname = NULL, *filename = NULL, *dir_name = NULL,
-	     *linkname = zalloc(size), *targetname, *tmp;
+	     *linkname = zalloc(size), *tmp;
 	int err = -1;
 
 	if (!is_kallsyms) {
@@ -336,14 +360,17 @@ int build_id_cache__add_s(const char *sbuild_id, const char *name,
 			goto out_free;
 	}
 
-	dir_name = build_id_cache__dirname_from_path(name, is_kallsyms, is_vdso);
+	dir_name = build_id_cache__dirname_from_path(name, is_kallsyms,
+						     is_vdso, sbuild_id);
 	if (!dir_name)
 		goto out_free;
 
 	if (mkdir_p(dir_name, 0755))
 		goto out_free;
 
-	if (asprintf(&filename, "%s/%s", dir_name, sbuild_id) < 0) {
+	/* Save the allocated buildid dirname */
+	if (asprintf(&filename, "%s/%s", dir_name,
+		     build_id_cache__basename(is_kallsyms, is_vdso)) < 0) {
 		filename = NULL;
 		goto out_free;
 	}
@@ -357,7 +384,7 @@ int build_id_cache__add_s(const char *sbuild_id, const char *name,
 			goto out_free;
 	}
 
-	if (!build_id__filename(sbuild_id, linkname, size))
+	if (!build_id_cache__linkname(sbuild_id, linkname, size))
 		goto out_free;
 	tmp = strrchr(linkname, '/');
 	*tmp = '\0';
@@ -366,10 +393,10 @@ int build_id_cache__add_s(const char *sbuild_id, const char *name,
 		goto out_free;
 
 	*tmp = '/';
-	targetname = filename + strlen(buildid_dir) - 5;
-	memcpy(targetname, "../..", 5);
+	tmp = dir_name + strlen(buildid_dir) - 5;
+	memcpy(tmp, "../..", 5);
 
-	if (symlink(targetname, linkname) == 0)
+	if (symlink(tmp, linkname) == 0)
 		err = 0;
 out_free:
 	if (!is_kallsyms)
@@ -394,7 +421,7 @@ static int build_id_cache__add_b(const u8 *build_id, size_t build_id_size,
 bool build_id_cache__cached(const char *sbuild_id)
 {
 	bool ret = false;
-	char *filename = build_id__filename(sbuild_id, NULL, 0);
+	char *filename = build_id_cache__linkname(sbuild_id, NULL, 0);
 
 	if (filename && !access(filename, F_OK))
 		ret = true;
@@ -413,7 +440,7 @@ int build_id_cache__remove_s(const char *sbuild_id)
 	if (filename == NULL || linkname == NULL)
 		goto out_free;
 
-	if (!build_id__filename(sbuild_id, linkname, size))
+	if (!build_id_cache__linkname(sbuild_id, linkname, size))
 		goto out_free;
 
 	if (access(linkname, F_OK))
@@ -431,7 +458,7 @@ int build_id_cache__remove_s(const char *sbuild_id)
 	tmp = strrchr(linkname, '/') + 1;
 	snprintf(tmp, size - (tmp - linkname), "%s", filename);
 
-	if (unlink(linkname))
+	if (rm_rf(linkname))
 		goto out_free;
 
 	err = 0;
@@ -443,7 +470,7 @@ out_free:
 
 static int dso__cache_build_id(struct dso *dso, struct machine *machine)
 {
-	bool is_kallsyms = dso->kernel && dso->long_name[0] != '/';
+	bool is_kallsyms = dso__is_kallsyms(dso);
 	bool is_vdso = dso__is_vdso(dso);
 	const char *name = dso->long_name;
 	char nm[PATH_MAX];
diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
index 24a507a..a63e169 100644
--- a/tools/perf/util/dso.h
+++ b/tools/perf/util/dso.h
@@ -325,6 +325,11 @@ static inline bool dso__is_kcore(struct dso *dso)
 	       dso->binary_type == DSO_BINARY_TYPE__GUEST_KCORE;
 }
 
+static inline bool dso__is_kallsyms(struct dso *dso)
+{
+	return dso->kernel && dso->long_name[0] != '/';
+}
+
 void dso__free_a2l(struct dso *dso);
 
 enum dso_type dso__type(struct dso *dso, struct machine *machine);
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index a3e80d6..1822ad3 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1699,7 +1699,7 @@ static char *dso__find_kallsyms(struct dso *dso, struct map *map)
 	if (!find_matching_kcore(map, path, sizeof(path)))
 		return strdup(path);
 
-	scnprintf(path, sizeof(path), "%s/[kernel.kallsyms]/%s",
+	scnprintf(path, sizeof(path), "%s/[kernel.kallsyms]/%s/kallsyms",
 		  buildid_dir, sbuild_id);
 
 	if (access(path, F_OK)) {

[RFC PATCH perf/core 02/13] perf probe: Simplify __add_probe_trace_events code

[Masami Hiramatsu]

Simplify the __add_probe_trace_events() code by taking out the
probe_trace_event__set_name() and updating show_perf_probe_event()

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/util/probe-event.c |   92 +++++++++++++++++++++++------------------
 1 file changed, 51 insertions(+), 41 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index d27edef..9dd6419 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2127,7 +2127,8 @@ kprobe_blacklist__find_by_address(struct list_head *blacklist,
 }
 
 /* Show an event */
-static int show_perf_probe_event(struct perf_probe_event *pev,
+static int show_perf_probe_event(const char *group, const char *event,
+				 struct perf_probe_event *pev,
 				 const char *module)
 {
 	int i, ret;
@@ -2139,7 +2140,7 @@ static int show_perf_probe_event(struct perf_probe_event *pev,
 	if (!place)
 		return -EINVAL;
 
-	ret = e_snprintf(buf, 128, "%s:%s", pev->group, pev->event);
+	ret = e_snprintf(buf, 128, "%s:%s", group, event);
 	if (ret < 0)
 		return ret;
 
@@ -2201,7 +2202,8 @@ static int __show_perf_probe_events(int fd, bool is_kprobe,
 			ret = convert_to_perf_probe_event(&tev, &pev,
 								is_kprobe);
 			if (ret >= 0)
-				ret = show_perf_probe_event(&pev,
+				ret = show_perf_probe_event(pev.group,
+							    pev.event, &pev,
 							    tev.point.module);
 		}
 next:
@@ -2374,18 +2376,55 @@ 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, *group;
 	struct strlist *namelist;
 	LIST_HEAD(blacklist);
 	struct kprobe_blacklist_node *node;
-	bool safename;
 
 	if (pev->uprobes)
 		fd = open_uprobe_events(true);
@@ -2411,7 +2450,6 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,
 			pr_debug("No kprobe blacklist support, ignored\n");
 	}
 
-	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++) {
@@ -2427,47 +2465,19 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,
 			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);
 		if (ret < 0)
 			break;
-		/* Add added event name to namelist */
-		strlist__add(namelist, event);
-
-		/* Trick here - save current event/group */
-		event = pev->event;
-		group = pev->group;
-		pev->event = tev->event;
-		pev->group = tev->group;
-		show_perf_probe_event(pev, tev->point.module);
-		/* Trick here - restore current event/group */
-		pev->event = (char *)event;
-		pev->group = (char *)group;
 
+		/* We use tev's name for showing new events */
+		show_perf_probe_event(tev->group, tev->event, pev,
+				      tev->point.module);
 		/*
 		 * Probes after the first probe which comes from same
 		 * user input are always allowed to add suffix, because

[RFC PATCH perf/core 03/13] perf probe: Move ftrace probe-event operations to probe-file.c

[Masami Hiramatsu]

Move ftrace probe-event operations to probe-file.c from probe-event.c.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/util/Build         |    1 
 tools/perf/util/probe-event.c |  319 +++--------------------------------------
 tools/perf/util/probe-event.h |    7 +
 tools/perf/util/probe-file.c  |  302 +++++++++++++++++++++++++++++++++++++++
 tools/perf/util/probe-file.h  |   18 ++
 5 files changed, 355 insertions(+), 292 deletions(-)
 create mode 100644 tools/perf/util/probe-file.c
 create mode 100644 tools/perf/util/probe-file.h

diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index e4b676d..e4f9c96 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -78,6 +78,7 @@ 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/probe-event.c b/tools/perf/util/probe-event.c
index 9dd6419..6c5ddb8 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 */
@@ -1415,8 +1411,7 @@ 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;
@@ -1899,7 +1894,7 @@ 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;
@@ -1924,119 +1919,6 @@ 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;
@@ -2190,7 +2072,7 @@ 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;
 
@@ -2228,89 +2110,20 @@ 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;
 }
 
@@ -2426,23 +2239,18 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,
 	LIST_HEAD(blacklist);
 	struct kprobe_blacklist_node *node;
 
-	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;
 	}
+
 	/* Get kprobe blacklist if exists */
 	if (!pev->uprobes) {
 		ret = kprobe_blacklist__load(&blacklist);
@@ -2471,7 +2279,7 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,
 		if (ret < 0)
 			break;
 
-		ret = write_probe_trace_event(fd, tev);
+		ret = probe_file__add_event(fd, tev);
 		if (ret < 0)
 			break;
 
@@ -2734,68 +2542,9 @@ 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)
@@ -2804,25 +2553,15 @@ 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;
@@ -2833,15 +2572,11 @@ 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 31db6ee..20f555d 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 0000000..2a7cc8c
--- /dev/null
+++ b/tools/perf/util/probe-file.c
@@ -0,0 +1,302 @@
+/*
+ * 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(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;
+}
+
+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(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;
+}
+
+/* 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 0000000..ada94a2
--- /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

[RFC PATCH perf/core 04/13] perf buildid: Use SBUILD_ID_SIZE macro

[Masami Hiramatsu]

Introduce SBUILD_ID_SIZE macro and use it instead of using
BUILD_ID_SIZE * 2 + 1.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/builtin-buildid-cache.c |    8 ++++----
 tools/perf/builtin-buildid-list.c  |    4 ++--
 tools/perf/util/build-id.c         |    4 ++--
 tools/perf/util/build-id.h         |    3 ++-
 4 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/tools/perf/builtin-buildid-cache.c b/tools/perf/builtin-buildid-cache.c
index d47a0cd..9845c2d 100644
--- a/tools/perf/builtin-buildid-cache.c
+++ b/tools/perf/builtin-buildid-cache.c
@@ -127,7 +127,7 @@ static int build_id_cache__kcore_existing(const char *from_dir, char *to_dir,
 
 static int build_id_cache__add_kcore(const char *filename, bool force)
 {
-	char dir[32], sbuildid[BUILD_ID_SIZE * 2 + 1];
+	char dir[32], sbuildid[SBUILD_ID_SIZE];
 	char from_dir[PATH_MAX], to_dir[PATH_MAX];
 	char *p;
 
@@ -184,7 +184,7 @@ static int build_id_cache__add_kcore(const char *filename, bool force)
 
 static int build_id_cache__add_file(const char *filename)
 {
-	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
+	char sbuild_id[SBUILD_ID_SIZE];
 	u8 build_id[BUILD_ID_SIZE];
 	int err;
 
@@ -204,7 +204,7 @@ static int build_id_cache__add_file(const char *filename)
 static int build_id_cache__remove_file(const char *filename)
 {
 	u8 build_id[BUILD_ID_SIZE];
-	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
+	char sbuild_id[SBUILD_ID_SIZE];
 
 	int err;
 
@@ -276,7 +276,7 @@ static int build_id_cache__fprintf_missing(struct perf_session *session, FILE *f
 static int build_id_cache__update_file(const char *filename)
 {
 	u8 build_id[BUILD_ID_SIZE];
-	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
+	char sbuild_id[SBUILD_ID_SIZE];
 
 	int err = 0;
 
diff --git a/tools/perf/builtin-buildid-list.c b/tools/perf/builtin-buildid-list.c
index 9fe93c8..b5ca988 100644
--- a/tools/perf/builtin-buildid-list.c
+++ b/tools/perf/builtin-buildid-list.c
@@ -20,7 +20,7 @@
 static int sysfs__fprintf_build_id(FILE *fp)
 {
 	u8 kallsyms_build_id[BUILD_ID_SIZE];
-	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
+	char sbuild_id[SBUILD_ID_SIZE];
 
 	if (sysfs__read_build_id("/sys/kernel/notes", kallsyms_build_id,
 				 sizeof(kallsyms_build_id)) != 0)
@@ -35,7 +35,7 @@ static int sysfs__fprintf_build_id(FILE *fp)
 static int filename__fprintf_build_id(const char *name, FILE *fp)
 {
 	u8 build_id[BUILD_ID_SIZE];
-	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
+	char sbuild_id[SBUILD_ID_SIZE];
 
 	if (filename__read_build_id(name, build_id,
 				    sizeof(build_id)) != sizeof(build_id))
diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
index 204d23d..1edb7c7 100644
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -132,7 +132,7 @@ char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size)
 {
 	bool is_kallsyms = dso__is_kallsyms((struct dso *)dso);
 	bool is_vdso = dso__is_vdso((struct dso *)dso);
-	char build_id_hex[BUILD_ID_SIZE * 2 + 1];
+	char build_id_hex[SBUILD_ID_SIZE];
 	char *linkname;
 	bool alloc = (bf == NULL);
 	int ret;
@@ -411,7 +411,7 @@ 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 8501122..ce2f493 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"

[RFC PATCH perf/core 05/13] perf buildid: Introduce sysfs/filename__sprintf_build_id

[Masami Hiramatsu]

Introduce sysfs/filename__sprintf_build_id for consolidating
similar code.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/builtin-buildid-cache.c |   14 ++------------
 tools/perf/builtin-buildid-list.c  |   24 ++++++++++--------------
 tools/perf/util/build-id.c         |   32 ++++++++++++++++++++++++++++++++
 tools/perf/util/build-id.h         |    3 +++
 4 files changed, 47 insertions(+), 26 deletions(-)

diff --git a/tools/perf/builtin-buildid-cache.c b/tools/perf/builtin-buildid-cache.c
index 9845c2d..cd1196b 100644
--- a/tools/perf/builtin-buildid-cache.c
+++ b/tools/perf/builtin-buildid-cache.c
@@ -25,8 +25,6 @@
 static int build_id_cache__kcore_buildid(const char *proc_dir, char *sbuildid)
 {
 	char root_dir[PATH_MAX];
-	char notes[PATH_MAX];
-	u8 build_id[BUILD_ID_SIZE];
 	char *p;
 
 	strlcpy(root_dir, proc_dir, sizeof(root_dir));
@@ -35,15 +33,7 @@ static int build_id_cache__kcore_buildid(const char *proc_dir, char *sbuildid)
 	if (!p)
 		return -1;
 	*p = '\0';
-
-	scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
-
-	if (sysfs__read_build_id(notes, build_id, sizeof(build_id)))
-		return -1;
-
-	build_id__sprintf(build_id, sizeof(build_id), sbuildid);
-
-	return 0;
+	return sysfs__sprintf_build_id(root_dir, sbuildid);
 }
 
 static int build_id_cache__kcore_dir(char *dir, size_t sz)
@@ -138,7 +128,7 @@ static int build_id_cache__add_kcore(const char *filename, bool force)
 		return -1;
 	*p = '\0';
 
-	if (build_id_cache__kcore_buildid(from_dir, sbuildid))
+	if (build_id_cache__kcore_buildid(from_dir, sbuildid) < 0)
 		return -1;
 
 	scnprintf(to_dir, sizeof(to_dir), "%s/[kernel.kcore]/%s",
diff --git a/tools/perf/builtin-buildid-list.c b/tools/perf/builtin-buildid-list.c
index b5ca988..918b4de 100644
--- a/tools/perf/builtin-buildid-list.c
+++ b/tools/perf/builtin-buildid-list.c
@@ -19,29 +19,25 @@
 
 static int sysfs__fprintf_build_id(FILE *fp)
 {
-	u8 kallsyms_build_id[BUILD_ID_SIZE];
 	char sbuild_id[SBUILD_ID_SIZE];
+	int ret;
 
-	if (sysfs__read_build_id("/sys/kernel/notes", kallsyms_build_id,
-				 sizeof(kallsyms_build_id)) != 0)
-		return -1;
+	ret = sysfs__sprintf_build_id("/", sbuild_id);
+	if (ret != sizeof(sbuild_id))
+		return ret < 0 ? ret : -EINVAL;
 
-	build_id__sprintf(kallsyms_build_id, sizeof(kallsyms_build_id),
-			  sbuild_id);
-	fprintf(fp, "%s\n", sbuild_id);
-	return 0;
+	return fprintf(fp, "%s\n", sbuild_id);
 }
 
 static int filename__fprintf_build_id(const char *name, FILE *fp)
 {
-	u8 build_id[BUILD_ID_SIZE];
 	char sbuild_id[SBUILD_ID_SIZE];
+	int ret;
 
-	if (filename__read_build_id(name, build_id,
-				    sizeof(build_id)) != sizeof(build_id))
-		return 0;
+	ret = filename__sprintf_build_id(name, sbuild_id);
+	if (ret != sizeof(sbuild_id))
+		return ret < 0 ? ret : -EINVAL;
 
-	build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
 	return fprintf(fp, "%s\n", sbuild_id);
 }
 
@@ -63,7 +59,7 @@ static int perf_session__list_build_ids(bool force, bool with_hits)
 	/*
 	 * See if this is an ELF file first:
 	 */
-	if (filename__fprintf_build_id(input_name, stdout))
+	if (filename__fprintf_build_id(input_name, stdout) > 0)
 		goto out;
 
 	session = perf_session__new(&file, false, &build_id__mark_dso_hit_ops);
diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
index 1edb7c7..8c40133 100644
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -93,6 +93,38 @@ int build_id__sprintf(const u8 *build_id, int len, char *bf)
 	return raw - build_id;
 }
 
+int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id)
+{
+	char notes[PATH_MAX];
+	u8 build_id[BUILD_ID_SIZE];
+	int ret;
+
+	if (!root_dir)
+		root_dir = "";
+
+	scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
+
+	ret = sysfs__read_build_id(notes, build_id, sizeof(build_id));
+	if (ret < 0)
+		return ret;
+
+	return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
+}
+
+int filename__sprintf_build_id(const char *pathname, char *sbuild_id)
+{
+	u8 build_id[BUILD_ID_SIZE];
+	int ret;
+
+	ret = filename__read_build_id(pathname, build_id, sizeof(build_id));
+	if (ret < 0)
+		return ret;
+	else if (ret != sizeof(build_id))
+		return -EINVAL;
+
+	return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
+}
+
 /* asnprintf consolidates asprintf and snprintf */
 static int asnprintf(char **strp, size_t size, const char *fmt, ...)
 {
diff --git a/tools/perf/util/build-id.h b/tools/perf/util/build-id.h
index ce2f493..27a14a8 100644
--- a/tools/perf/util/build-id.h
+++ b/tools/perf/util/build-id.h
@@ -12,6 +12,9 @@ extern struct perf_tool build_id__mark_dso_hit_ops;
 struct dso;
 
 int build_id__sprintf(const u8 *build_id, int len, char *bf);
+int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id);
+int filename__sprintf_build_id(const char *pathname, char *sbuild_id);
+
 char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size);
 
 int build_id__mark_dso_hit(struct perf_tool *tool, union perf_event *event,

[RFC PATCH perf/core 06/13] perf: Add lsdir to read a directory

[Masami Hiramatsu]

As a utility function, add lsdir() which reads given
directory and store entry name into a strlist.
lsdir accepts a filter function so that user can
filter out unneeded entries.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/util/util.c |   34 ++++++++++++++++++++++++++++++++++
 tools/perf/util/util.h |    4 ++++
 2 files changed, 38 insertions(+)

diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index 0c264bc..2af5b40 100644
--- a/tools/perf/util/util.c
+++ b/tools/perf/util/util.c
@@ -115,6 +115,40 @@ int rm_rf(char *path)
 	return rmdir(path);
 }
 
+/* A filter which removes dot files */
+bool lsdir_no_dot_filter(const char *dirname __maybe_unused, struct dirent *d)
+{
+	return d->d_name[0] != '.';
+}
+
+/* lsdir reads a directory and store it in strlist */
+struct strlist *lsdir(const char *dirname,
+		      bool (*filter)(const char *, struct dirent *))
+{
+	struct strlist *list = NULL;
+	DIR *dir;
+	struct dirent *d;
+
+	dir = opendir(dirname);
+	if (!dir)
+		return NULL;
+
+	list = strlist__new(true, NULL);
+	if (!list) {
+		errno = -ENOMEM;
+		goto out;
+	}
+
+	while ((d = readdir(dir)) != NULL) {
+		if (!filter || filter(dirname, d))
+			strlist__add(list, d->d_name);
+	}
+
+out:
+	closedir(dir);
+	return list;
+}
+
 static int slow_copyfile(const char *from, const char *to, mode_t mode)
 {
 	int err = -1;
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index 8bce58b..5afa003 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -79,6 +79,7 @@
 #include <termios.h>
 #include <linux/bitops.h>
 #include <termios.h>
+#include "strlist.h"
 
 extern const char *graph_line;
 extern const char *graph_dotted_line;
@@ -250,6 +251,9 @@ static inline int sane_case(int x, int high)
 
 int mkdir_p(char *path, mode_t mode);
 int rm_rf(char *path);
+struct strlist *lsdir(const char *dirname,
+		      bool (*filter)(const char *, struct dirent *));
+bool lsdir_no_dot_filter(const char *dirname __maybe_unused, struct dirent *d);
 int copyfile(const char *from, const char *to);
 int copyfile_mode(const char *from, const char *to, mode_t mode);
 int copyfile_offset(int fromfd, loff_t from_ofs, int tofd, loff_t to_ofs, u64 size);

[RFC PATCH perf/core 07/13] perf-buildid-cache: Use lsdir for looking up buildid caches

[Masami Hiramatsu]

Use new lsdir() for looking up buildid caches. This changes
logic a bit to ignore all dot files, since the build-id
cache must not start with dot.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/util/build-id.c |   30 +++++-------------------------
 1 file changed, 5 insertions(+), 25 deletions(-)

diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
index 8c40133..02a5e0d 100644
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -342,38 +342,18 @@ int build_id_cache__list_build_ids(const char *pathname,
 {
 	struct strlist *list;
 	char *dir_name;
-	DIR *dir;
-	struct dirent *d;
 	int ret = 0;
 
-	list = strlist__new(true, NULL);
 	dir_name = build_id_cache__dirname_from_path(pathname, false, false,
 						     NULL);
-	if (!list || !dir_name) {
-		ret = -ENOMEM;
-		goto out;
-	}
+	if (!dir_name)
+		return -ENOMEM;
 
-	/* List up all dirents */
-	dir = opendir(dir_name);
-	if (!dir) {
+	list = lsdir(dir_name, lsdir_no_dot_filter);
+	if (!list)
 		ret = -errno;
-		goto out;
-	}
-
-	while ((d = readdir(dir)) != NULL) {
-		if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
-			continue;
-		strlist__add(list, d->d_name);
-	}
-	closedir(dir);
-
-out:
+	*result = list;
 	free(dir_name);
-	if (ret)
-		strlist__delete(list);
-	else
-		*result = list;
 
 	return ret;
 }

[RFC PATCH perf/core 08/13] perf probe: Check kprobe blacklist in converting phase

[Masami Hiramatsu]

Instead of checking kprobe blacklist in writing phase, check it
in converting phase.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/util/probe-event.c |   92 ++++++++++++++++++++++++-----------------
 1 file changed, 54 insertions(+), 38 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 6c5ddb8..e8c3a25 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -549,6 +549,8 @@ static int add_module_to_probe_trace_events(struct probe_trace_event *tevs,
 	return ret;
 }
 
+static bool kprobe_blacklist__listed(unsigned long address);
+
 /* Post processing the probe events */
 static int post_process_probe_trace_events(struct probe_trace_event *tevs,
 					   int ntevs, const char *module,
@@ -575,27 +577,32 @@ static int post_process_probe_trace_events(struct probe_trace_event *tevs,
 	etext_addr = kernel_get_symbol_address_by_name("_etext", false);
 
 	for (i = 0; i < ntevs; i++) {
-		if (tevs[i].point.address && !tevs[i].point.retprobe) {
-			/* If we found a wrong one, mark it by NULL symbol */
-			if (etext_addr < tevs[i].point.address) {
-				pr_warning("%s+%lu is out of .text, skip it.\n",
-				   tevs[i].point.symbol, tevs[i].point.offset);
-				tmp = NULL;
-				skipped++;
-			} else {
-				tmp = strdup(reloc_sym->name);
-				if (!tmp)
-					return -ENOMEM;
-			}
-			/* If we have no realname, use symbol for it */
-			if (!tevs[i].point.realname)
-				tevs[i].point.realname = tevs[i].point.symbol;
-			else
-				free(tevs[i].point.symbol);
-			tevs[i].point.symbol = tmp;
-			tevs[i].point.offset = tevs[i].point.address -
-					       reloc_sym->unrelocated_addr;
+		if (!tevs[i].point.address || tevs[i].point.retprobe)
+			continue;
+		/* If we found a wrong one, mark it by NULL symbol */
+		if (etext_addr < tevs[i].point.address) {
+			pr_warning("%s+%lu is out of .text, skip it.\n",
+			   tevs[i].point.symbol, tevs[i].point.offset);
+			tmp = NULL;
+			skipped++;
+		} else if (kprobe_blacklist__listed(tevs[i].point.address)) {
+			pr_warning("%s is blacklisted function, skip it.\n",
+				   tevs[i].point.symbol);
+			tmp = NULL;
+			skipped++;
+		} else {
+			tmp = strdup(reloc_sym->name);
+			if (!tmp)
+				return -ENOMEM;
 		}
+		/* If we have no realname, use symbol for it */
+		if (!tevs[i].point.realname)
+			tevs[i].point.realname = tevs[i].point.symbol;
+		else
+			free(tevs[i].point.symbol);
+		tevs[i].point.symbol = tmp;
+		tevs[i].point.offset = tevs[i].point.address -
+				       reloc_sym->unrelocated_addr;
 	}
 	return skipped;
 }
@@ -2008,6 +2015,27 @@ kprobe_blacklist__find_by_address(struct list_head *blacklist,
 	return NULL;
 }
 
+static LIST_HEAD(kprobe_blacklist);
+
+static void kprobe_blacklist__init(void)
+{
+	if (!list_empty(&kprobe_blacklist))
+		return;
+
+	if (kprobe_blacklist__load(&kprobe_blacklist) < 0)
+		pr_debug("No kprobe blacklist support, ignored\n");
+}
+
+static void kprobe_blacklist__release(void)
+{
+	kprobe_blacklist__delete(&kprobe_blacklist);
+}
+
+static bool kprobe_blacklist__listed(unsigned long address)
+{
+	return !!kprobe_blacklist__find_by_address(&kprobe_blacklist, address);
+}
+
 /* Show an event */
 static int show_perf_probe_event(const char *group, const char *event,
 				 struct perf_probe_event *pev,
@@ -2236,8 +2264,6 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,
 	int i, fd, ret;
 	struct probe_trace_event *tev = NULL;
 	struct strlist *namelist;
-	LIST_HEAD(blacklist);
-	struct kprobe_blacklist_node *node;
 
 	fd = probe_file__open(PF_FL_RW | (pev->uprobes ? PF_FL_UPROBE : 0));
 	if (fd < 0)
@@ -2251,27 +2277,13 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,
 		goto close_out;
 	}
 
-	/* Get kprobe blacklist if exists */
-	if (!pev->uprobes) {
-		ret = kprobe_blacklist__load(&blacklist);
-		if (ret < 0)
-			pr_debug("No kprobe blacklist support, ignored\n");
-	}
-
 	ret = 0;
 	pr_info("Added new event%s\n", (ntevs > 1) ? "s:" : ":");
 	for (i = 0; i < ntevs; i++) {
 		tev = &tevs[i];
-		/* Skip if the symbol is out of .text (marked previously) */
+		/* Skip if the symbol is out of .text or blacklisted */
 		if (!tev->point.symbol)
 			continue;
-		/* Ensure that the address is NOT blacklisted */
-		node = kprobe_blacklist__find_by_address(&blacklist,
-							 tev->point.address);
-		if (node) {
-			pr_warning("Warning: Skipped probing on blacklisted function: %s\n", node->symbol);
-			continue;
-		}
 
 		/* Set new name for tev (and update namelist) */
 		ret = probe_trace_event__set_name(tev, pev, namelist,
@@ -2305,7 +2317,6 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,
 			 tev->event);
 	}
 
-	kprobe_blacklist__delete(&blacklist);
 	strlist__delete(namelist);
 close_out:
 	close(fd);
@@ -2513,6 +2524,9 @@ int add_perf_probe_events(struct perf_probe_event *pevs, int npevs)
 	/* Loop 1: convert all events */
 	for (i = 0; i < npevs; i++) {
 		pkgs[i].pev = &pevs[i];
+		/* Init kprobe blacklist if needed */
+		if (!pkgs[i].pev->uprobes)
+			kprobe_blacklist__init();
 		/* Convert with or without debuginfo */
 		ret  = convert_to_probe_trace_events(pkgs[i].pev,
 						     &pkgs[i].tevs);
@@ -2520,6 +2534,8 @@ int add_perf_probe_events(struct perf_probe_event *pevs, int npevs)
 			goto end;
 		pkgs[i].ntevs = ret;
 	}
+	/* This just release blacklist only if allocated */
+	kprobe_blacklist__release();
 
 	/* Loop 2: add all events */
 	for (i = 0; i < npevs; i++) {

[RFC PATCH perf/core 09/13] perf probe: Use strbuf for making strings in probe-event.c

[Masami Hiramatsu]

Replace many fixed-length char array with strbuf to
stringify perf_probe_event and probe_trace_event etc. in
util/probe-event.c.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/util/probe-event.c  |  225 ++++++++++++++--------------------------
 tools/perf/util/probe-event.h  |    3 -
 tools/perf/util/probe-finder.c |   10 +-
 3 files changed, 85 insertions(+), 153 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index e8c3a25..707be38 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -1517,69 +1517,52 @@ out:
 }
 
 /* Compose only probe arg */
-int synthesize_perf_probe_arg(struct perf_probe_arg *pa, char *buf, size_t len)
+char *synthesize_perf_probe_arg(struct perf_probe_arg *pa)
 {
 	struct perf_probe_arg_field *field = pa->field;
-	int ret;
-	char *tmp = buf;
+	struct strbuf buf;
+	char *ret;
 
+	strbuf_init(&buf, 64);
 	if (pa->name && pa->var)
-		ret = e_snprintf(tmp, len, "%s=%s", pa->name, pa->var);
+		strbuf_addf(&buf, "%s=%s", pa->name, pa->var);
 	else
-		ret = e_snprintf(tmp, len, "%s", pa->name ? pa->name : pa->var);
-	if (ret <= 0)
-		goto error;
-	tmp += ret;
-	len -= ret;
+		strbuf_addstr(&buf, pa->name ?: pa->var);
 
 	while (field) {
 		if (field->name[0] == '[')
-			ret = e_snprintf(tmp, len, "%s", field->name);
+			strbuf_addstr(&buf, field->name);
 		else
-			ret = e_snprintf(tmp, len, "%s%s",
-					 field->ref ? "->" : ".", field->name);
-		if (ret <= 0)
-			goto error;
-		tmp += ret;
-		len -= ret;
+			strbuf_addf(&buf, "%s%s", field->ref ? "->" : ".",
+				    field->name);
 		field = field->next;
 	}
 
-	if (pa->type) {
-		ret = e_snprintf(tmp, len, ":%s", pa->type);
-		if (ret <= 0)
-			goto error;
-		tmp += ret;
-		len -= ret;
-	}
+	if (pa->type)
+		strbuf_addf(&buf, ":%s", pa->type);
+
+	ret = strbuf_detach(&buf, NULL);
+	strbuf_release(&buf);
 
-	return tmp - buf;
-error:
-	pr_debug("Failed to synthesize perf probe argument: %d\n", ret);
 	return ret;
 }
 
 /* Compose only probe point (not argument) */
 static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
 {
-	char *buf, *tmp;
-	char offs[32] = "", line[32] = "", file[32] = "";
-	int ret, len;
-
-	buf = zalloc(MAX_CMDLEN);
-	if (buf == NULL) {
-		ret = -ENOMEM;
-		goto error;
-	}
-	if (pp->offset) {
-		ret = e_snprintf(offs, 32, "+%lu", pp->offset);
-		if (ret <= 0)
-			goto error;
-	}
-	if (pp->line) {
-		ret = e_snprintf(line, 32, ":%d", pp->line);
-		if (ret <= 0)
-			goto error;
+	struct strbuf buf;
+	char *tmp;
+	int len;
+
+	strbuf_init(&buf, 64);
+	if (pp->function) {
+		strbuf_addstr(&buf, pp->function);
+		if (pp->offset)
+			strbuf_addf(&buf, "+%lu", pp->offset);
+		else if (pp->line)
+			strbuf_addf(&buf, ":%d", pp->line);
+		else if (pp->retprobe)
+			strbuf_addstr(&buf, "%return");
 	}
 	if (pp->file) {
 		tmp = pp->file;
@@ -1588,25 +1571,14 @@ static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
 			tmp = strchr(pp->file + len - 30, '/');
 			tmp = tmp ? tmp + 1 : pp->file + len - 30;
 		}
-		ret = e_snprintf(file, 32, "@%s", tmp);
-		if (ret <= 0)
-			goto error;
+		strbuf_addf(&buf, "@%s", tmp);
+		if (!pp->function && pp->line)
+			strbuf_addf(&buf, ":%d", pp->line);
 	}
 
-	if (pp->function)
-		ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s%s", pp->function,
-				 offs, pp->retprobe ? "%return" : "", line,
-				 file);
-	else
-		ret = e_snprintf(buf, MAX_CMDLEN, "%s%s", file, line);
-	if (ret <= 0)
-		goto error;
-
-	return buf;
-error:
-	pr_debug("Failed to synthesize perf probe point: %d\n", ret);
-	free(buf);
-	return NULL;
+	tmp = strbuf_detach(&buf, NULL);
+	strbuf_release(&buf);
+	return tmp;
 }
 
 #if 0
@@ -1635,45 +1607,30 @@ char *synthesize_perf_probe_command(struct perf_probe_event *pev)
 #endif
 
 static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref,
-					     char **buf, size_t *buflen,
-					     int depth)
+					    struct strbuf *buf, int depth)
 {
-	int ret;
 	if (ref->next) {
 		depth = __synthesize_probe_trace_arg_ref(ref->next, buf,
-							 buflen, depth + 1);
+							 depth + 1);
 		if (depth < 0)
 			goto out;
 	}
-
-	ret = e_snprintf(*buf, *buflen, "%+ld(", ref->offset);
-	if (ret < 0)
-		depth = ret;
-	else {
-		*buf += ret;
-		*buflen -= ret;
-	}
+	strbuf_addf(buf, "%+ld(", ref->offset);
 out:
 	return depth;
-
 }
 
 static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
-				       char *buf, size_t buflen)
+				      struct strbuf *buf)
 {
 	struct probe_trace_arg_ref *ref = arg->ref;
-	int ret, depth = 0;
-	char *tmp = buf;
+	int depth = 0;
 
 	/* Argument name or separator */
 	if (arg->name)
-		ret = e_snprintf(buf, buflen, " %s=", arg->name);
+		strbuf_addf(buf, " %s=", arg->name);
 	else
-		ret = e_snprintf(buf, buflen, " ");
-	if (ret < 0)
-		return ret;
-	buf += ret;
-	buflen -= ret;
+		strbuf_addch(buf, ' ');
 
 	/* Special case: @XXX */
 	if (arg->value[0] == '@' && arg->ref)
@@ -1681,86 +1638,58 @@ static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
 
 	/* Dereferencing arguments */
 	if (ref) {
-		depth = __synthesize_probe_trace_arg_ref(ref, &buf,
-							  &buflen, 1);
+		depth = __synthesize_probe_trace_arg_ref(ref, buf, 1);
 		if (depth < 0)
 			return depth;
 	}
 
 	/* Print argument value */
 	if (arg->value[0] == '@' && arg->ref)
-		ret = e_snprintf(buf, buflen, "%s%+ld", arg->value,
-				 arg->ref->offset);
+		strbuf_addf(buf, "%s%+ld", arg->value, arg->ref->offset);
 	else
-		ret = e_snprintf(buf, buflen, "%s", arg->value);
-	if (ret < 0)
-		return ret;
-	buf += ret;
-	buflen -= ret;
+		strbuf_addstr(buf, arg->value);
 
 	/* Closing */
-	while (depth--) {
-		ret = e_snprintf(buf, buflen, ")");
-		if (ret < 0)
-			return ret;
-		buf += ret;
-		buflen -= ret;
-	}
+	while (depth--)
+		strbuf_addch(buf, ')');
 	/* Print argument type */
-	if (arg->type) {
-		ret = e_snprintf(buf, buflen, ":%s", arg->type);
-		if (ret <= 0)
-			return ret;
-		buf += ret;
-	}
+	if (arg->type)
+		strbuf_addf(buf, ":%s", arg->type);
 
-	return buf - tmp;
+	return 0;
 }
 
 char *synthesize_probe_trace_command(struct probe_trace_event *tev)
 {
 	struct probe_trace_point *tp = &tev->point;
-	char *buf;
-	int i, len, ret;
-
-	buf = zalloc(MAX_CMDLEN);
-	if (buf == NULL)
-		return NULL;
-
-	len = e_snprintf(buf, MAX_CMDLEN, "%c:%s/%s ", tp->retprobe ? 'r' : 'p',
-			 tev->group, tev->event);
-	if (len <= 0)
-		goto error;
+	struct strbuf buf;
+	char *ret = NULL;
+	int i;
 
 	/* Uprobes must have tp->address and tp->module */
 	if (tev->uprobes && (!tp->address || !tp->module))
-		goto error;
+		return NULL;
+
+	strbuf_init(&buf, 32);
+	strbuf_addf(&buf, "%c:%s/%s ", tp->retprobe ? 'r' : 'p',
+		    tev->group, tev->event);
 
 	/* Use the tp->address for uprobes */
 	if (tev->uprobes)
-		ret = e_snprintf(buf + len, MAX_CMDLEN - len, "%s:0x%lx",
-				 tp->module, tp->address);
+		strbuf_addf(&buf, "%s:0x%lx", tp->module, tp->address);
 	else
-		ret = e_snprintf(buf + len, MAX_CMDLEN - len, "%s%s%s+%lu",
-				 tp->module ?: "", tp->module ? ":" : "",
-				 tp->symbol, tp->offset);
-
-	if (ret <= 0)
-		goto error;
-	len += ret;
+		strbuf_addf(&buf, "%s%s%s+%lu", tp->module ?: "",
+			    tp->module ? ":" : "", tp->symbol, tp->offset);
 
 	for (i = 0; i < tev->nargs; i++) {
-		ret = synthesize_probe_trace_arg(&tev->args[i], buf + len,
-						  MAX_CMDLEN - len);
-		if (ret <= 0)
+		if (synthesize_probe_trace_arg(&tev->args[i], &buf) < 0)
 			goto error;
-		len += ret;
 	}
 
-	return buf;
+	ret = strbuf_detach(&buf, NULL);
 error:
-	free(buf);
-	return NULL;
+	strbuf_release(&buf);
+	return ret;
 }
 
 static int find_perf_probe_point_from_map(struct probe_trace_point *tp,
@@ -1838,7 +1767,7 @@ static int convert_to_perf_probe_point(struct probe_trace_point *tp,
 static int convert_to_perf_probe_event(struct probe_trace_event *tev,
 			       struct perf_probe_event *pev, bool is_kprobe)
 {
-	char buf[64] = "";
+	struct strbuf buf = STRBUF_INIT;
 	int i, ret;
 
 	/* Convert event/group name */
@@ -1861,9 +1790,10 @@ static int convert_to_perf_probe_event(struct probe_trace_event *tev,
 		if (tev->args[i].name)
 			pev->args[i].name = strdup(tev->args[i].name);
 		else {
-			ret = synthesize_probe_trace_arg(&tev->args[i],
-							  buf, 64);
-			pev->args[i].name = strdup(buf);
+			strbuf_init(&buf, 32);
+			ret = synthesize_probe_trace_arg(&tev->args[i], &buf);
+			pev->args[i].name = strbuf_detach(&buf, NULL);
+			strbuf_release(&buf);
 		}
 		if (pev->args[i].name == NULL && ret >= 0)
 			ret = -ENOMEM;
@@ -2042,33 +1972,36 @@ static int show_perf_probe_event(const char *group, const char *event,
 				 const char *module)
 {
 	int i, ret;
-	char buf[128];
-	char *place;
+	char *buf, *place;
 
 	/* Synthesize only event probe point */
 	place = synthesize_perf_probe_point(&pev->point);
 	if (!place)
 		return -EINVAL;
 
-	ret = e_snprintf(buf, 128, "%s:%s", group, event);
+	ret = asprintf(&buf, "%s:%s", group, event);
 	if (ret < 0)
-		return ret;
+		return -errno;
 
 	pr_info("  %-20s (on %s", buf, place);
+	free(buf);
 	if (module)
 		pr_info(" in %s", module);
 
 	if (pev->nargs > 0) {
 		pr_info(" with");
 		for (i = 0; i < pev->nargs; i++) {
-			ret = synthesize_perf_probe_arg(&pev->args[i],
-							buf, 128);
-			if (ret < 0)
-				break;
+			buf = synthesize_perf_probe_arg(&pev->args[i]);
+			if (!buf) {
+				ret = -ENOMEM;
+				goto out;
+			}
 			pr_info(" %s", buf);
+			free(buf);
 		}
 	}
 	pr_info(")\n");
+out:
 	free(place);
 	return ret;
 }
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index 20f555d..4cff6be 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -115,8 +115,7 @@ extern int parse_probe_trace_command(const char *cmd,
 /* Events to command string */
 extern char *synthesize_perf_probe_command(struct perf_probe_event *pev);
 extern char *synthesize_probe_trace_command(struct probe_trace_event *tev);
-extern int synthesize_perf_probe_arg(struct perf_probe_arg *pa, char *buf,
-				     size_t len);
+extern char *synthesize_perf_probe_arg(struct perf_probe_arg *pa);
 
 /* Check the perf_probe_event needs debuginfo */
 extern bool perf_probe_event_need_dwarf(struct perf_probe_event *pev);
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index c50da39..b2d60b2 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -550,7 +550,7 @@ static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
 static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf)
 {
 	Dwarf_Die vr_die;
-	char buf[32], *ptr;
+	char *buf, *ptr;
 	int ret = 0;
 
 	if (!is_c_varname(pf->pvar->var)) {
@@ -575,13 +575,13 @@ static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf)
 	if (pf->pvar->name)
 		pf->tvar->name = strdup(pf->pvar->name);
 	else {
-		ret = synthesize_perf_probe_arg(pf->pvar, buf, 32);
-		if (ret < 0)
-			return ret;
+		buf = synthesize_perf_probe_arg(pf->pvar);
+		if (!buf)
+			return -ENOMEM;
 		ptr = strchr(buf, ':');	/* Change type separator to _ */
 		if (ptr)
 			*ptr = '_';
-		pf->tvar->name = strdup(buf);
+		pf->tvar->name = buf;
 	}
 	if (pf->tvar->name == NULL)
 		return -ENOMEM;

[RFC PATCH perf/core 10/13] perf probe: Add --cache option to cache the probe definitions

[Masami Hiramatsu]

Add --cache option to cache the probe definitions. This
just saves the result of the dwarf analysis to probe cache.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/builtin-probe.c    |    1 
 tools/perf/util/build-id.c    |   13 +-
 tools/perf/util/build-id.h    |    2 
 tools/perf/util/probe-event.c |  136 +++++++++++++++----
 tools/perf/util/probe-event.h |    5 +
 tools/perf/util/probe-file.c  |  298 +++++++++++++++++++++++++++++++++++++++++
 tools/perf/util/probe-file.h  |   20 +++
 7 files changed, 443 insertions(+), 32 deletions(-)

diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index 1272559..97f4d07 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -397,6 +397,7 @@ __cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
 		     opt_set_filter),
 	OPT_CALLBACK('x', "exec", NULL, "executable|path",
 			"target executable name or path", opt_set_target),
+	OPT_BOOLEAN(0, "cache", &probe_conf.cache, "Manipulate probe cache"),
 	OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
 		    "Enable symbol demangling"),
 	OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
index 02a5e0d..169639e 100644
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -313,9 +313,8 @@ void disable_buildid_cache(void)
 	no_buildid_cache = true;
 }
 
-static char *build_id_cache__dirname_from_path(const char *name,
-					       bool is_kallsyms, bool is_vdso,
-					       const char *sbuild_id)
+char *build_id_cache__dirname_from_path(const char *sbuild_id, const char *name,
+					bool is_kallsyms, bool is_vdso)
 {
 	char *realname = (char *)name, *filename;
 	bool slash = is_kallsyms || is_vdso;
@@ -344,8 +343,8 @@ int build_id_cache__list_build_ids(const char *pathname,
 	char *dir_name;
 	int ret = 0;
 
-	dir_name = build_id_cache__dirname_from_path(pathname, false, false,
-						     NULL);
+	dir_name = build_id_cache__dirname_from_path(NULL, pathname,
+						     false, false);
 	if (!dir_name)
 		return -ENOMEM;
 
@@ -372,8 +371,8 @@ int build_id_cache__add_s(const char *sbuild_id, const char *name,
 			goto out_free;
 	}
 
-	dir_name = build_id_cache__dirname_from_path(name, is_kallsyms,
-						     is_vdso, sbuild_id);
+	dir_name = build_id_cache__dirname_from_path(sbuild_id, name,
+						     is_kallsyms, is_vdso);
 	if (!dir_name)
 		goto out_free;
 
diff --git a/tools/perf/util/build-id.h b/tools/perf/util/build-id.h
index 27a14a8..a1f428d 100644
--- a/tools/perf/util/build-id.h
+++ b/tools/perf/util/build-id.h
@@ -27,6 +27,8 @@ bool perf_session__read_build_ids(struct perf_session *session, bool with_hits);
 int perf_session__write_buildid_table(struct perf_session *session, int fd);
 int perf_session__cache_build_ids(struct perf_session *session);
 
+char *build_id_cache__dirname_from_path(const char *sbuild_id, const char *name,
+					bool is_kallsyms, bool is_vdso);
 int build_id_cache__list_build_ids(const char *pathname,
 				   struct strlist **result);
 bool build_id_cache__cached(const char *sbuild_id);
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 707be38..ea40d1da 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -68,7 +68,6 @@ int e_snprintf(char *str, size_t size, const char *format, ...)
 	return ret;
 }
 
-static char *synthesize_perf_probe_point(struct perf_probe_point *pp);
 static struct machine *host_machine;
 
 /* Initialize symbol maps and path of vmlinux/modules */
@@ -1548,7 +1547,7 @@ char *synthesize_perf_probe_arg(struct perf_probe_arg *pa)
 }
 
 /* Compose only probe point (not argument) */
-static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
+char *synthesize_perf_probe_point(struct perf_probe_point *pp)
 {
 	struct strbuf buf;
 	char *tmp;
@@ -1581,30 +1580,36 @@ static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
 	return tmp;
 }
 
-#if 0
 char *synthesize_perf_probe_command(struct perf_probe_event *pev)
 {
-	char *buf;
-	int i, len, ret;
+	struct strbuf buf;
+	char *tmp;
+	int i;
 
-	buf = synthesize_perf_probe_point(&pev->point);
-	if (!buf)
-		return NULL;
+	strbuf_init(&buf, 64);
+	if (pev->event)
+		strbuf_addf(&buf, "%s:%s=", pev->group ?: PERFPROBE_GROUP,
+			    pev->event);
+
+	tmp = synthesize_perf_probe_point(&pev->point);
+	if (!tmp)
+		goto out;
+	strbuf_addstr(&buf, tmp);
+	free(tmp);
 
-	len = strlen(buf);
 	for (i = 0; i < pev->nargs; i++) {
-		ret = e_snprintf(&buf[len], MAX_CMDLEN - len, " %s",
-				 pev->args[i].name);
-		if (ret <= 0) {
-			free(buf);
-			return NULL;
-		}
-		len += ret;
+		tmp = synthesize_perf_probe_arg(pev->args + i);
+		if (!tmp)
+			goto out;
+		strbuf_addf(&buf, " %s", tmp);
+		free(tmp);
 	}
 
-	return buf;
+	tmp = strbuf_detach(&buf, NULL);
+out:
+	strbuf_release(&buf);
+	return tmp;
 }
-#endif
 
 static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref,
 					    struct strbuf *buf, int depth)
@@ -1685,7 +1690,6 @@ char *synthesize_probe_trace_command(struct probe_trace_event *tev)
 		if (synthesize_probe_trace_arg(&tev->args[i], &buf) < 0)
 			goto error;
 	}
-
 	ret = strbuf_detach(&buf, NULL);
 error:
 	strbuf_release(&buf);
@@ -1831,6 +1835,79 @@ void clear_perf_probe_event(struct perf_probe_event *pev)
 	memset(pev, 0, sizeof(*pev));
 }
 
+#define strdup_or_goto(str, label)	\
+({ char *__p = NULL; if (str && !(__p = strdup(str))) goto label; __p; })
+
+static int perf_probe_point__copy(struct perf_probe_point *dst,
+				  struct perf_probe_point *src)
+{
+	dst->file = strdup_or_goto(src->file, out_err);
+	dst->function = strdup_or_goto(src->function, out_err);
+	dst->lazy_line = strdup_or_goto(src->lazy_line, out_err);
+	dst->line = src->line;
+	dst->retprobe = src->retprobe;
+	dst->offset = src->offset;
+	return 0;
+
+out_err:
+	clear_perf_probe_point(dst);
+	return -ENOMEM;
+}
+
+static int perf_probe_arg__copy(struct perf_probe_arg *dst,
+				struct perf_probe_arg *src)
+{
+	struct perf_probe_arg_field *field, **ppfield;
+
+	dst->name = strdup_or_goto(src->name, out_err);
+	dst->var = strdup_or_goto(src->var, out_err);
+	dst->type = strdup_or_goto(src->type, out_err);
+
+	field = src->field;
+	ppfield = &(dst->field);
+	while (field) {
+		*ppfield = zalloc(sizeof(*field));
+		if (!*ppfield)
+			goto out_err;
+		(*ppfield)->name = strdup_or_goto(field->name, out_err);
+		(*ppfield)->index = field->index;
+		(*ppfield)->ref = field->ref;
+		field = field->next;
+		ppfield = &((*ppfield)->next);
+	}
+	return 0;
+out_err:
+	return -ENOMEM;
+}
+
+int perf_probe_event__copy(struct perf_probe_event *dst,
+			   struct perf_probe_event *src)
+{
+	int i;
+
+	dst->event = strdup_or_goto(src->event, out_err);
+	dst->group = strdup_or_goto(src->group, out_err);
+	dst->target = strdup_or_goto(src->target, out_err);
+	dst->uprobes = src->uprobes;
+
+	if (perf_probe_point__copy(&dst->point, &src->point) < 0)
+		goto out_err;
+
+	dst->args = zalloc(sizeof(struct perf_probe_arg) * src->nargs);
+	if (!dst->args)
+		goto out_err;
+	dst->nargs = src->nargs;
+
+	for (i = 0; i < src->nargs; i++)
+		if (perf_probe_arg__copy(&dst->args[i], &src->args[i]) < 0)
+			goto out_err;
+	return 0;
+
+out_err:
+	clear_perf_probe_event(dst);
+	return -ENOMEM;
+}
+
 void clear_probe_trace_event(struct probe_trace_event *tev)
 {
 	struct probe_trace_arg_ref *ref, *next;
@@ -2191,14 +2268,16 @@ static int probe_trace_event__set_name(struct probe_trace_event *tev,
 }
 
 static int __add_probe_trace_events(struct perf_probe_event *pev,
-				     struct probe_trace_event *tevs,
-				     int ntevs, bool allow_suffix)
+				    struct probe_trace_event *tevs,
+				    int ntevs, bool allow_suffix)
 {
 	int i, fd, ret;
 	struct probe_trace_event *tev = NULL;
+	struct probe_cache *cache = NULL;
 	struct strlist *namelist;
+	int flag = PF_FL_RW | (pev->uprobes ? PF_FL_UPROBE : 0);
 
-	fd = probe_file__open(PF_FL_RW | (pev->uprobes ? PF_FL_UPROBE : 0));
+	fd = probe_file__open(flag);
 	if (fd < 0)
 		return fd;
 
@@ -2244,6 +2323,16 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,
 
 	/* Note that it is possible to skip all events because of blacklist */
 	if (ret >= 0 && tev->event) {
+		if (probe_conf.cache) {
+			cache = probe_cache__new(pev->target);
+			if (!cache)
+				pr_info("Warning: Failed to add cache\n");
+			else {
+				probe_cache__add_entry(cache, pev, tevs, ntevs);
+				probe_cache__commit(cache);
+				probe_cache__delete(cache);
+			}
+		}
 		/* Show how to use the event. */
 		pr_info("\nYou can now use it in all perf tools, such as:\n\n");
 		pr_info("\tperf record -e %s:%s -aR sleep 1\n\n", tev->group,
@@ -2273,9 +2362,6 @@ static int find_probe_functions(struct map *map, char *name)
 	return found;
 }
 
-#define strdup_or_goto(str, label)	\
-	({ char *__p = strdup(str); if (!__p) goto label; __p; })
-
 void __weak arch__fix_tev_from_maps(struct perf_probe_event *pev __maybe_unused,
 				struct probe_trace_event *tev __maybe_unused,
 				struct map *map __maybe_unused) { }
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index 4cff6be..9aceba3 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -12,6 +12,7 @@ struct probe_conf {
 	bool	show_location_range;
 	bool	force_add;
 	bool	no_inlines;
+	bool	cache;
 	int	max_probes;
 };
 extern struct probe_conf probe_conf;
@@ -116,6 +117,10 @@ extern int parse_probe_trace_command(const char *cmd,
 extern char *synthesize_perf_probe_command(struct perf_probe_event *pev);
 extern char *synthesize_probe_trace_command(struct probe_trace_event *tev);
 extern char *synthesize_perf_probe_arg(struct perf_probe_arg *pa);
+char *synthesize_perf_probe_point(struct perf_probe_point *pp);
+
+int perf_probe_event__copy(struct perf_probe_event *dst,
+			   struct perf_probe_event *src);
 
 /* Check the perf_probe_event needs debuginfo */
 extern bool perf_probe_event_need_dwarf(struct perf_probe_event *pev);
diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
index 2a7cc8c..572e8c2 100644
--- a/tools/perf/util/probe-file.c
+++ b/tools/perf/util/probe-file.c
@@ -14,6 +14,7 @@
  * GNU General Public License for more details.
  *
  */
+#include <sys/uio.h>
 #include "util.h"
 #include "event.h"
 #include "strlist.h"
@@ -300,3 +301,300 @@ int probe_file__del_events(int fd, struct strfilter *filter)
 	return ret;
 }
 
+static void probe_cache_entry__delete(struct probe_cache_entry *node)
+{
+	if (!list_empty(&node->list))
+		list_del(&node->list);
+	if (node->tevlist)
+		strlist__delete(node->tevlist);
+	clear_perf_probe_event(&node->pev);
+	free(node->spev);
+	free(node);
+}
+
+static struct probe_cache_entry *
+probe_cache_entry__new(struct perf_probe_event *pev)
+{
+	struct probe_cache_entry *ret = zalloc(sizeof(*ret));
+
+	if (ret) {
+		INIT_LIST_HEAD(&ret->list);
+		ret->tevlist = strlist__new(true, NULL);
+		if (!ret->tevlist)
+			zfree(&ret);
+		if (ret && pev) {
+			ret->spev = synthesize_perf_probe_command(pev);
+			if (!ret->spev ||
+			    perf_probe_event__copy(&ret->pev, pev) < 0) {
+				probe_cache_entry__delete(ret);
+				return NULL;
+			}
+		}
+	}
+
+	return ret;
+}
+
+/* For the kernel probe caches, pass target = NULL */
+static int probe_cache__open(struct probe_cache *pcache, const char *target)
+{
+	char cpath[PATH_MAX];
+	char sbuildid[SBUILD_ID_SIZE];
+	char *dir_name;
+	bool is_kallsyms = !target;
+	int ret, fd;
+
+	if (target)
+		ret = filename__sprintf_build_id(target, sbuildid);
+	else {
+		target = "[kernel.kallsyms]";
+		ret = sysfs__sprintf_build_id("/", sbuildid);
+	}
+	if (ret < 0) {
+		pr_warning("Failed to get build-id from %s.\n", target ?: "kernel");
+		return ret;
+	}
+
+	/* If we have no buildid cache, make it */
+	if (!build_id_cache__cached(sbuildid)) {
+		ret = build_id_cache__add_s(sbuildid, target,
+					    is_kallsyms, NULL);
+		if (ret < 0) {
+			pr_warning("Failed to add cache: %s\n", target);
+			return ret;
+		}
+	}
+
+	dir_name = build_id_cache__dirname_from_path(sbuildid, target,
+						     is_kallsyms, false);
+	if (!dir_name)
+		return -ENOMEM;
+
+	snprintf(cpath, PATH_MAX, "%s/probes", dir_name);
+	fd = open(cpath, O_CREAT | O_RDWR | O_APPEND, 0644);
+	if (fd < 0)
+		pr_warning("Failed to open cache(%d): %s\n", fd, cpath);
+	free(dir_name);
+	pcache->fd = fd;
+
+	return fd;
+}
+
+static int probe_cache__load(struct probe_cache *pcache)
+{
+	struct probe_cache_entry *entry = NULL;
+	char buf[MAX_CMDLEN], *p;
+	int ret = 0;
+	FILE *fp;
+
+	fp = fdopen(dup(pcache->fd), "r");
+	while (!feof(fp)) {
+		if (!fgets(buf, MAX_CMDLEN, fp))
+			break;
+		p = strchr(buf, '\n');
+		if (p)
+			*p = '\0';
+		if (buf[0] == '#') {	/* #perf_probe_event */
+			entry = probe_cache_entry__new(NULL);
+			entry->spev = strdup(buf + 1);
+			ret = parse_perf_probe_command(buf + 1, &entry->pev);
+			if (!entry->spev || ret < 0) {
+				probe_cache_entry__delete(entry);
+				goto out;
+			}
+			list_add_tail(&entry->list, &pcache->list);
+		} else {	/* trace_probe_event */
+			if (!entry) {
+				ret = -EINVAL;
+				goto out;
+			}
+			strlist__add(entry->tevlist, buf);
+		}
+	}
+out:
+	fclose(fp);
+	return ret;
+}
+
+static struct probe_cache *probe_cache__alloc(void)
+{
+	struct probe_cache *ret = zalloc(sizeof(*ret));
+
+	if (ret) {
+		INIT_LIST_HEAD(&ret->list);
+		ret->fd = -EINVAL;
+	}
+	return ret;
+}
+
+void probe_cache__delete(struct probe_cache *pcache)
+{
+	struct probe_cache_entry *entry;
+
+	if (!pcache)
+		return;
+
+	while (!list_empty(&pcache->list)) {
+		entry = list_first_entry(&pcache->list, typeof(*entry), list);
+		probe_cache_entry__delete(entry);
+	}
+	if (pcache->fd > 0)
+		close(pcache->fd);
+	free(pcache);
+}
+
+struct probe_cache *probe_cache__new(const char *target)
+{
+	struct probe_cache *pcache = probe_cache__alloc();
+	int ret;
+
+	if (!pcache)
+		return NULL;
+
+	ret = probe_cache__open(pcache, target);
+	if (ret < 0) {
+		pr_debug("Cache open error: %d\n", ret);
+		goto out_err;
+	}
+
+	ret = probe_cache__load(pcache);
+	if (ret < 0) {
+		pr_debug("Cache read error: %d\n", ret);
+		goto out_err;
+	}
+
+	return pcache;
+
+out_err:
+	probe_cache__delete(pcache);
+	return NULL;
+}
+
+static bool streql(const char *a, const char *b)
+{
+	if (a == b)
+		return true;
+
+	if (!a || !b)
+		return false;
+
+	return !strcmp(a, b);
+}
+
+static struct probe_cache_entry *
+probe_cache__find(struct probe_cache *pcache, struct perf_probe_event *pev)
+{
+	struct probe_cache_entry *entry = NULL;
+	char *cmd = NULL;
+
+	cmd = synthesize_perf_probe_command(pev);
+	if (!cmd)
+		return NULL;
+
+	list_for_each_entry(entry, &pcache->list, list) {
+		/* Hit if same event name or same command-string */
+		if ((pev->event &&
+		     (streql(entry->pev.group, pev->group) &&
+		      streql(entry->pev.event, pev->event))) ||
+		    (!strcmp(entry->spev, cmd)))
+			goto found;
+	}
+	entry = NULL;
+
+found:
+	free(cmd);
+	return entry;
+}
+
+int probe_cache__add_entry(struct probe_cache *pcache,
+			   struct perf_probe_event *pev,
+			   struct probe_trace_event *tevs, int ntevs)
+{
+	struct probe_cache_entry *entry = NULL;
+	char *command;
+	int i, ret = 0;
+
+	if (!pcache || !pev || !tevs || ntevs <= 0) {
+		ret = -EINVAL;
+		goto out_err;
+	}
+
+	/* Remove old cache entry */
+	entry = probe_cache__find(pcache, pev);
+	if (entry)
+		probe_cache_entry__delete(entry);
+
+	ret = -ENOMEM;
+	entry = probe_cache_entry__new(pev);
+	if (!entry)
+		goto out_err;
+
+	for (i = 0; i < ntevs; i++) {
+		if (!tevs[i].point.symbol)
+			continue;
+
+		command = synthesize_probe_trace_command(&tevs[i]);
+		if (!command)
+			goto out_err;
+		strlist__add(entry->tevlist, command);
+		free(command);
+	}
+	list_add_tail(&entry->list, &pcache->list);
+	pr_debug("Added probe cache: %d\n", ntevs);
+	return 0;
+
+out_err:
+	pr_debug("Failed to add probe caches\n");
+	if (entry)
+		probe_cache_entry__delete(entry);
+	return ret;
+}
+
+static int probe_cache_entry__write(struct probe_cache_entry *entry, int fd)
+{
+	struct str_node *snode;
+	struct iovec iov[3];
+	int ret;
+
+	pr_debug("Writing cache: #%s\n", entry->spev);
+	iov[0].iov_base = (void *)"#"; iov[0].iov_len = 1;
+	iov[1].iov_base = entry->spev; iov[1].iov_len = strlen(entry->spev);
+	iov[2].iov_base = (void *)"\n"; iov[2].iov_len = 1;
+	ret = writev(fd, iov, 3);
+	if (ret < 0)
+		return ret;
+
+	strlist__for_each(snode, entry->tevlist) {
+		iov[0].iov_base = (void *)snode->s;
+		iov[0].iov_len = strlen(snode->s);
+		iov[1].iov_base = (void *)"\n"; iov[1].iov_len = 1;
+		ret = writev(fd, iov, 2);
+		if (ret < 0)
+			return ret;
+	}
+	return 0;
+}
+
+int probe_cache__commit(struct probe_cache *pcache)
+{
+	struct probe_cache_entry *entry;
+	int ret = 0;
+
+	/* TBD: if we do not update existing entries, skip it */
+	ret = lseek(pcache->fd, 0, SEEK_SET);
+	if (ret < 0)
+		goto out;
+
+	ret = ftruncate(pcache->fd, 0);
+	if (ret < 0)
+		goto out;
+
+	list_for_each_entry(entry, &pcache->list, list) {
+		ret = probe_cache_entry__write(entry, pcache->fd);
+		pr_debug("Cache committed: %d\n", ret);
+		if (ret < 0)
+			break;
+	}
+out:
+	return ret;
+}
diff --git a/tools/perf/util/probe-file.h b/tools/perf/util/probe-file.h
index ada94a2..7b473b39 100644
--- a/tools/perf/util/probe-file.h
+++ b/tools/perf/util/probe-file.h
@@ -15,4 +15,24 @@ 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);
 
+/* Cache of probe definitions */
+struct probe_cache_entry {
+	struct list_head	list;
+	struct perf_probe_event pev;
+	char			*spev;
+	struct strlist		*tevlist;
+};
+
+struct probe_cache {
+	int	fd;
+	struct list_head list;
+};
+
+struct probe_cache *probe_cache__new(const char *target);
+int probe_cache__add_entry(struct probe_cache *pcache,
+			   struct perf_probe_event *pev,
+			   struct probe_trace_event *tevs, int ntevs);
+int probe_cache__commit(struct probe_cache *pcache);
+void probe_cache__delete(struct probe_cache *pcache);
+
 #endif

[RFC PATCH perf/core 11/13] perf probe: Use cache entry if possible

[Masami Hiramatsu]

Before analyzing debuginfo, try to find a corresponding entry
from probe cache always. This does not depend on --cache,
the --cache enables to store/update cache, but looking up
the cache is always enabled.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/util/probe-event.c |   58 +++++++++++++++++++++++++++++++++++++++++
 tools/perf/util/probe-file.c  |   20 +++++++++++++-
 tools/perf/util/probe-file.h  |    5 +++-
 3 files changed, 81 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index ea40d1da..00fe6e7 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2489,6 +2489,59 @@ err_out:
 
 bool __weak arch__prefers_symtab(void) { return false; }
 
+static int find_probe_trace_events_from_cache(struct perf_probe_event *pev,
+					      struct probe_trace_event **tevs)
+{
+	struct probe_cache *cache;
+	struct probe_cache_entry *entry;
+	struct probe_trace_event *tev;
+	struct str_node *node;
+	int ret, i;
+
+	cache = probe_cache__new(pev->target);
+	if (!cache)
+		return 0;
+
+	entry = probe_cache__find(cache, pev);
+
+	if (!entry && !pev->event &&
+	    (!pev->point.file && pev->point.function && !pev->point.retprobe &&
+	     !pev->point.line && !pev->point.offset && !pev->point.lazy_line)) {
+		entry = probe_cache__find_by_name(cache, pev->group,
+						  pev->point.function);
+	}
+	if (!entry) {
+		ret = 0;
+		goto out;
+	}
+
+	ret = strlist__nr_entries(entry->tevlist);
+	if (ret > probe_conf.max_probes) {
+		pr_debug("Too many entries matched in the cache of %s\n",
+			 pev->target ? : "kernel");
+		ret = -E2BIG;
+		goto out;
+	}
+
+	*tevs = zalloc(ret * sizeof(*tev));
+	if (!*tevs) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	i = 0;
+	strlist__for_each(node, entry->tevlist) {
+		ret = parse_probe_trace_command(node->s, &(*tevs)[i++]);
+		if (ret < 0)
+			goto out;
+	}
+	ret = i;
+
+out:
+	probe_cache__delete(cache);
+	return ret;
+}
+
 static int convert_to_probe_trace_events(struct perf_probe_event *pev,
 					 struct probe_trace_event **tevs)
 {
@@ -2503,6 +2556,11 @@ static int convert_to_probe_trace_events(struct perf_probe_event *pev,
 		}
 	}
 
+	/* At first, we need to lookup cache entry */
+	ret = find_probe_trace_events_from_cache(pev, tevs);
+	if (ret > 0)
+		return ret;	/* Found in probe cache */
+
 	if (arch__prefers_symtab() && !perf_probe_event_need_dwarf(pev)) {
 		ret = find_probe_trace_events_from_map(pev, tevs);
 		if (ret > 0)
diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
index 572e8c2..984f690 100644
--- a/tools/perf/util/probe-file.c
+++ b/tools/perf/util/probe-file.c
@@ -481,7 +481,7 @@ static bool streql(const char *a, const char *b)
 	return !strcmp(a, b);
 }
 
-static struct probe_cache_entry *
+struct probe_cache_entry *
 probe_cache__find(struct probe_cache *pcache, struct perf_probe_event *pev)
 {
 	struct probe_cache_entry *entry = NULL;
@@ -506,6 +506,24 @@ found:
 	return entry;
 }
 
+struct probe_cache_entry *
+probe_cache__find_by_name(struct probe_cache *pcache,
+			  const char *group, const char *event)
+{
+	struct probe_cache_entry *entry = NULL;
+
+	list_for_each_entry(entry, &pcache->list, list) {
+		/* Hit if same event name or same command-string */
+		if (streql(entry->pev.group, group) &&
+		    streql(entry->pev.event, event))
+			goto found;
+	}
+	entry = NULL;
+
+found:
+	return entry;
+}
+
 int probe_cache__add_entry(struct probe_cache *pcache,
 			   struct perf_probe_event *pev,
 			   struct probe_trace_event *tevs, int ntevs)
diff --git a/tools/perf/util/probe-file.h b/tools/perf/util/probe-file.h
index 7b473b39..833e061 100644
--- a/tools/perf/util/probe-file.h
+++ b/tools/perf/util/probe-file.h
@@ -34,5 +34,8 @@ int probe_cache__add_entry(struct probe_cache *pcache,
 			   struct probe_trace_event *tevs, int ntevs);
 int probe_cache__commit(struct probe_cache *pcache);
 void probe_cache__delete(struct probe_cache *pcache);
-
+struct probe_cache_entry *probe_cache__find(struct probe_cache *pcache,
+					    struct perf_probe_event *pev);
+struct probe_cache_entry *probe_cache__find_by_name(struct probe_cache *pcache,
+					const char *group, const char *event);
 #endif

[RFC PATCH perf/core 12/13] perf probe: Show all cached probes

[Masami Hiramatsu]

perf probe --list shows all cached probes when --cache
is given. Each caches are shown with on which binary that
probed. e.g.
  -----
  # perf probe --cache vfs_read \$params
  # perf probe --cache -x /lib64/libc-2.17.so getaddrinfo \$params
  # ./perf probe --cache --list
  /[kernel.kallsyms] (1466a0a250b5d0070c6d0f03c5fed30b237970a1):
  vfs_read $params
  /usr/lib64/libc-2.17.so (c31ffe7942bfd77b2fca8f9bd5709d387a86d3bc):
  getaddrinfo $params
  -----
Note that $params requires debuginfo.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/builtin-probe.c    |    2 +
 tools/perf/util/build-id.c    |   79 ++++++++++++++++++++++++++++++++++++++++-
 tools/perf/util/build-id.h    |    3 ++
 tools/perf/util/probe-event.c |    3 ++
 tools/perf/util/probe-file.c  |   63 ++++++++++++++++++++++++++++++++-
 tools/perf/util/probe-file.h  |    1 +
 6 files changed, 146 insertions(+), 5 deletions(-)

diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index 97f4d07..1e09329 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -44,7 +44,7 @@
 
 #define DEFAULT_VAR_FILTER "!__k???tab_* & !__crc_*"
 #define DEFAULT_FUNC_FILTER "!_*"
-#define DEFAULT_LIST_FILTER "*:*"
+#define DEFAULT_LIST_FILTER "*"
 
 /* Session management structure */
 static struct {
diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
index 169639e..63123c1 100644
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -144,8 +144,7 @@ static int asnprintf(char **strp, size_t size, const char *fmt, ...)
 	return ret;
 }
 
-static char *build_id_cache__linkname(const char *sbuild_id, char *bf,
-				      size_t size)
+char *build_id_cache__linkname(const char *sbuild_id, char *bf, size_t size)
 {
 	char *tmp = bf;
 	int ret = asnprintf(&bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
@@ -155,6 +154,29 @@ static char *build_id_cache__linkname(const char *sbuild_id, char *bf,
 	return bf;
 }
 
+char *build_id_cache__origname(const char *sbuild_id)
+{
+	char *linkname;
+	char buf[PATH_MAX];
+	char *ret = NULL, *p;
+
+	linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
+	if (!linkname)
+		return NULL;
+
+	if (readlink(linkname, buf, PATH_MAX) < 0)
+		goto out;
+	/* The link should be "../..<origpath>/<sbuild_id>" */
+	p = strrchr(buf, '/');	/* Cut off the "/<sbuild_id>" */
+	if (p) {
+		*p = '\0';
+		ret = strdup(buf + 5);	/* Skip "../.." */
+	}
+out:
+	free(linkname);
+	return ret;
+}
+
 static const char *build_id_cache__basename(bool is_kallsyms, bool is_vdso)
 {
 	return is_kallsyms ? "kallsyms" : (is_vdso ? "vdso" : "elf");
@@ -313,6 +335,59 @@ void disable_buildid_cache(void)
 	no_buildid_cache = true;
 }
 
+int build_id_cache__list_all(struct strlist **result)
+{
+	struct strlist *toplist, *list, *bidlist;
+	struct str_node *nd, *nd2;
+	char *topdir, *linkdir;
+	char sbuild_id[SBUILD_ID_SIZE];
+	int ret = 0;
+
+	/* Open the top-level directory */
+	if (asprintf(&topdir, "%s/.build-id/", buildid_dir) < 0)
+		return -errno;
+	toplist = lsdir(topdir, lsdir_no_dot_filter);
+	if (!toplist) {
+		pr_debug("Failed to opendir %s\n", topdir);
+		ret = -errno;
+		goto out;
+	}
+	bidlist = strlist__new(true, NULL);
+	strlist__for_each(nd, toplist) {
+		if (asprintf(&linkdir, "%s/%s", topdir, nd->s) < 0) {
+			ret = -errno;
+			goto out;
+		}
+		/* Open the lower-level directory */
+		list = lsdir(linkdir, lsdir_no_dot_filter);
+		if (!list) {
+			pr_debug("Failed to open %s: %d\n", linkdir, -errno);
+			goto next;
+		}
+		strlist__for_each(nd2, list) {
+			ret = snprintf(sbuild_id, SBUILD_ID_SIZE, "%s%s",
+					nd->s, nd2->s);
+			if (ret != SBUILD_ID_SIZE - 1) {
+				pr_debug("%s/%s is not buildid cache\n",
+					nd->s, nd2->s);
+				continue;
+			}
+			strlist__add(bidlist, sbuild_id);
+		}
+		strlist__delete(list);
+next:
+		free(linkdir);
+	}
+
+	*result = bidlist;
+out:
+	if (toplist)
+		strlist__delete(toplist);
+	free(topdir);
+
+	return ret;
+}
+
 char *build_id_cache__dirname_from_path(const char *sbuild_id, const char *name,
 					bool is_kallsyms, bool is_vdso)
 {
diff --git a/tools/perf/util/build-id.h b/tools/perf/util/build-id.h
index a1f428d..2d5c61c 100644
--- a/tools/perf/util/build-id.h
+++ b/tools/perf/util/build-id.h
@@ -27,8 +27,11 @@ bool perf_session__read_build_ids(struct perf_session *session, bool with_hits);
 int perf_session__write_buildid_table(struct perf_session *session, int fd);
 int perf_session__cache_build_ids(struct perf_session *session);
 
+char *build_id_cache__origname(const char *sbuild_id);
+char *build_id_cache__linkname(const char *sbuild_id, char *bf, size_t size);
 char *build_id_cache__dirname_from_path(const char *sbuild_id, const char *name,
 					bool is_kallsyms, bool is_vdso);
+int build_id_cache__list_all(struct strlist **result);
 int build_id_cache__list_build_ids(const char *pathname,
 				   struct strlist **result);
 bool build_id_cache__cached(const char *sbuild_id);
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 00fe6e7..e89675d 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2144,6 +2144,9 @@ int show_perf_probe_events(struct strfilter *filter)
 
 	setup_pager();
 
+	if (probe_conf.cache)
+		return probe_cache__show_all_caches(filter);
+
 	ret = init_symbol_maps(false);
 	if (ret < 0)
 		return ret;
diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
index 984f690..10dcec5 100644
--- a/tools/perf/util/probe-file.c
+++ b/tools/perf/util/probe-file.c
@@ -340,10 +340,17 @@ static int probe_cache__open(struct probe_cache *pcache, const char *target)
 {
 	char cpath[PATH_MAX];
 	char sbuildid[SBUILD_ID_SIZE];
-	char *dir_name;
+	char *dir_name = NULL;
 	bool is_kallsyms = !target;
 	int ret, fd;
 
+	if (target && build_id_cache__cached(target)) {
+		/* This is a cached buildid */
+		strncpy(sbuildid, target, SBUILD_ID_SIZE);
+		dir_name = build_id_cache__linkname(sbuildid, NULL, 0);
+		goto found;
+	}
+
 	if (target)
 		ret = filename__sprintf_build_id(target, sbuildid);
 	else {
@@ -367,8 +374,11 @@ static int probe_cache__open(struct probe_cache *pcache, const char *target)
 
 	dir_name = build_id_cache__dirname_from_path(sbuildid, target,
 						     is_kallsyms, false);
-	if (!dir_name)
+found:
+	if (!dir_name) {
+		pr_debug("Failed to get cache from %s\n", target);
 		return -ENOMEM;
+	}
 
 	snprintf(cpath, PATH_MAX, "%s/probes", dir_name);
 	fd = open(cpath, O_CREAT | O_RDWR | O_APPEND, 0644);
@@ -616,3 +626,52 @@ int probe_cache__commit(struct probe_cache *pcache)
 out:
 	return ret;
 }
+
+static int probe_cache__show_entries(struct probe_cache *pcache,
+				     struct strfilter *filter)
+{
+	struct probe_cache_entry *entry;
+	char buf[128], *ptr;
+
+	list_for_each_entry(entry, &pcache->list, list) {
+		if (entry->pev.event) {
+			ptr = buf;
+			snprintf(buf, 128, "%s:%s", entry->pev.group, entry->pev.event);
+		} else
+			ptr = entry->spev;
+		if (strfilter__compare(filter, ptr))
+			printf("%s\n", entry->spev);
+	}
+	return 0;
+}
+
+/* Show all cached probes */
+int probe_cache__show_all_caches(struct strfilter *filter)
+{
+	struct probe_cache *pcache;
+	struct strlist *bidlist;
+	struct str_node *nd;
+	char *buf;
+	int ret;
+
+	buf = strfilter__string(filter);
+	pr_debug("list cache with filter: %s\n", buf);
+	free(buf);
+
+	ret = build_id_cache__list_all(&bidlist);
+	if (ret < 0) {
+		pr_debug("Failed to get buildids: %d\n", ret);
+		return ret;
+	}
+	strlist__for_each(nd, bidlist) {
+		pcache = probe_cache__new(nd->s);
+		if (!pcache)
+			continue;
+		buf = build_id_cache__origname(nd->s);
+		printf("%s (%s):\n", buf, nd->s);
+		free(buf);
+		probe_cache__show_entries(pcache, filter);
+		probe_cache__delete(pcache);
+	}
+	return 0;
+}
diff --git a/tools/perf/util/probe-file.h b/tools/perf/util/probe-file.h
index 833e061..26dc4f7 100644
--- a/tools/perf/util/probe-file.h
+++ b/tools/perf/util/probe-file.h
@@ -38,4 +38,5 @@ struct probe_cache_entry *probe_cache__find(struct probe_cache *pcache,
 					    struct perf_probe_event *pev);
 struct probe_cache_entry *probe_cache__find_by_name(struct probe_cache *pcache,
 					const char *group, const char *event);
+int probe_cache__show_all_caches(struct strfilter *filter);
 #endif

[RFC PATCH perf/core 13/13] perf probe: Remove caches when --cache is given

[Masami Hiramatsu]

perf-probe --del removes caches when --cache is given.
Note that the delete pattern is not same as normal events.

If you cached probes with event name, --del "eventname"
works as expected. However, if you skipped it, the cached
probes doesn't have actual event name. In that case
 --del "probe-desc" is required. For example a cache entry
has the probe-desc "vfs_read $params", you can remove it with
--del "vfs_read*\$params".

  -----
  # perf probe --cache --list
  /[kernel.kallsyms] (1466a0a250b5d0070c6d0f03c5fed30b237970a1):
  vfs_read $params
  /usr/lib64/libc-2.17.so (c31ffe7942bfd77b2fca8f9bd5709d387a86d3bc):
  getaddrinfo $params

  # perf probe --cache --del vfs_read\*
  Removed event: probe:vfs_read

  # perf probe --cache --list
  /[kernel.kallsyms] (1466a0a250b5d0070c6d0f03c5fed30b237970a1):
  /usr/lib64/libc-2.17.so (c31ffe7942bfd77b2fca8f9bd5709d387a86d3bc):
  getaddrinfo $params
  -----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/util/probe-event.c |   26 ++++++++++++++++++++++++++
 tools/perf/util/probe-file.c  |   33 +++++++++++++++++++++++++--------
 tools/perf/util/probe-file.h  |    2 ++
 3 files changed, 53 insertions(+), 8 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index e89675d..07381a6 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2638,6 +2638,30 @@ end:
 	return ret;
 }
 
+static int del_perf_probe_caches(struct strfilter *filter)
+{
+	struct probe_cache *cache;
+	struct strlist *bidlist;
+	struct str_node *nd;
+	int ret;
+
+	ret = build_id_cache__list_all(&bidlist);
+	if (ret < 0) {
+		pr_debug("Failed to get buildids: %d\n", ret);
+		return ret;
+	}
+
+	strlist__for_each(nd, bidlist) {
+		cache = probe_cache__new(nd->s);
+		if (!cache)
+			continue;
+		probe_cache__remove_entries(cache, filter);
+		probe_cache__commit(cache);
+		probe_cache__delete(cache);
+	}
+	return 0;
+}
+
 int del_perf_probe_events(struct strfilter *filter)
 {
 	int ret, ret2, ufd = -1, kfd = -1;
@@ -2647,6 +2671,8 @@ int del_perf_probe_events(struct strfilter *filter)
 		return -EINVAL;
 
 	pr_debug("Delete filter: \'%s\'\n", str);
+	if (probe_conf.cache)
+		return del_perf_probe_caches(filter);
 
 	/* Get current event names */
 	ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
index 10dcec5..c7e4cf8 100644
--- a/tools/perf/util/probe-file.c
+++ b/tools/perf/util/probe-file.c
@@ -371,7 +371,6 @@ static int probe_cache__open(struct probe_cache *pcache, const char *target)
 			return ret;
 		}
 	}
-
 	dir_name = build_id_cache__dirname_from_path(sbuildid, target,
 						     is_kallsyms, false);
 found:
@@ -627,19 +626,37 @@ out:
 	return ret;
 }
 
+static bool probe_cache_entry__compare(struct probe_cache_entry *entry,
+				       struct strfilter *filter)
+{
+	char buf[128], *ptr = entry->spev;
+
+	if (entry->pev.event) {
+		snprintf(buf, 128, "%s:%s", entry->pev.group, entry->pev.event);
+		ptr = buf;
+	}
+	return strfilter__compare(filter, ptr);
+}
+
+int probe_cache__remove_entries(struct probe_cache *pcache,
+				struct strfilter *filter)
+{
+	struct probe_cache_entry *entry, *tmp;
+
+	list_for_each_entry_safe(entry, tmp, &pcache->list, list) {
+		if (probe_cache_entry__compare(entry, filter))
+			probe_cache_entry__delete(entry);
+	}
+	return 0;
+}
+
 static int probe_cache__show_entries(struct probe_cache *pcache,
 				     struct strfilter *filter)
 {
 	struct probe_cache_entry *entry;
-	char buf[128], *ptr;
 
 	list_for_each_entry(entry, &pcache->list, list) {
-		if (entry->pev.event) {
-			ptr = buf;
-			snprintf(buf, 128, "%s:%s", entry->pev.group, entry->pev.event);
-		} else
-			ptr = entry->spev;
-		if (strfilter__compare(filter, ptr))
+		if (probe_cache_entry__compare(entry, filter))
 			printf("%s\n", entry->spev);
 	}
 	return 0;
diff --git a/tools/perf/util/probe-file.h b/tools/perf/util/probe-file.h
index 26dc4f7..391fde0 100644
--- a/tools/perf/util/probe-file.h
+++ b/tools/perf/util/probe-file.h
@@ -34,6 +34,8 @@ int probe_cache__add_entry(struct probe_cache *pcache,
 			   struct probe_trace_event *tevs, int ntevs);
 int probe_cache__commit(struct probe_cache *pcache);
 void probe_cache__delete(struct probe_cache *pcache);
+int probe_cache__remove_entries(struct probe_cache *pcache,
+				struct strfilter *filter);
 struct probe_cache_entry *probe_cache__find(struct probe_cache *pcache,
 					    struct perf_probe_event *pev);
 struct probe_cache_entry *probe_cache__find_by_name(struct probe_cache *pcache,