[tip:perf/core] perf probe: Make --list show only available cached events

tip-bot for Masami Hiramatsu
2016-07-14T07:06:51Z

Commit-ID: c3492a3a4e58117f18d96125e67b0bed7c4231e1
Gitweb: http://git.kernel.org/tip/c3492a3a4e58117f18d96125e67b0bed7c4231e1
Author: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
AuthorDate: Tue, 12 Jul 2016 19:04:54 +0900
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Wed, 13 Jul 2016 23:09:05 -0300

perf probe: Make --list show only available cached events

Make "perf probe --cache --list" show only available cached events by
checking build-id validity.

E.g. without this patch:
----
$ ./perf probe --cache --add oldevent=cmd_probe
$ make #(to update ./perf)
$ ./perf probe --cache --add newevent=cmd_probe
$ ./perf probe --cache --list
/home/mhiramat/ksrc/linux/tools/perf/perf (061e90539bac69
probe_perf:newevent=cmd_probe
/home/mhiramat/ksrc/linux/tools/perf/perf (c2e44d614e33e1
probe_perf:oldevent=cmd_probe
----
It shows both of old and new events but user can not use old one.
With this;
----
$ ./perf probe --cache -l
/home/mhiramat/ksrc/linux/tools/perf/perf (061e90539bac69
probe_perf:newevent=cmd_probe
----

This shows only new events which are on the existing binary.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146831789417.17065.17896487479879669610.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/builtin-probe.c | 2 +-
tools/perf/util/build-id.c | 33 ++++++++++++++++++++++++++++++++-
tools/perf/util/build-id.h | 2 +-
tools/perf/util/probe-file.c | 2 +-
4 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index c6d890a..ee5b421 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -370,7 +370,7 @@ static int del_perf_probe_caches(struct strfilter *filter)
struct str_node *nd;
int ret;

- bidlist = build_id_cache__list_all();
+ bidlist = build_id_cache__list_all(false);
if (!bidlist) {
ret = -errno;
pr_debug("Failed to get buildids: %d\n", ret);
diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
index 1e504e4..36b4279 100644
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -206,6 +206,31 @@ out:
return ret;
}

+/* Check if the given build_id cache is valid on current running system */
+static bool build_id_cache__valid_id(char *sbuild_id)
+{
+ char real_sbuild_id[SBUILD_ID_SIZE] = "";
+ char *pathname;
+ int ret = 0;
+ bool result = false;
+
+ pathname = build_id_cache__origname(sbuild_id);
+ if (!pathname)
+ return false;
+
+ if (!strcmp(pathname, DSO__NAME_KALLSYMS))
+ ret = sysfs__sprintf_build_id("/", real_sbuild_id);
+ else if (pathname[0] == '/')
+ ret = filename__sprintf_build_id(pathname, real_sbuild_id);
+ else
+ ret = -EINVAL; /* Should we support other special DSO cache? */
+ if (ret >= 0)
+ result = (strcmp(sbuild_id, real_sbuild_id) == 0);
+ free(pathname);
+
+ return result;
+}
+
static const char *build_id_cache__basename(bool is_kallsyms, bool is_vdso)
{
return is_kallsyms ? "kallsyms" : (is_vdso ? "vdso" : "elf");
@@ -433,13 +458,17 @@ static bool lsdir_bid_tail_filter(const char *name __maybe_unused,
return (i == SBUILD_ID_SIZE - 3) && (d->d_name[i] == '\0');
}

-struct strlist *build_id_cache__list_all(void)
+struct strlist *build_id_cache__list_all(bool validonly)
{
struct strlist *toplist, *linklist = NULL, *bidlist;
struct str_node *nd, *nd2;
char *topdir, *linkdir = NULL;
char sbuild_id[SBUILD_ID_SIZE];

+ /* for filename__ functions */
+ if (validonly)
+ symbol__init(NULL);
+
/* Open the top-level directory */
if (asprintf(&topdir, "%s/.build-id/", buildid_dir) < 0)
return NULL;
@@ -470,6 +499,8 @@ struct strlist *build_id_cache__list_all(void)
if (snprintf(sbuild_id, SBUILD_ID_SIZE, "%s%s",
nd->s, nd2->s) != SBUILD_ID_SIZE - 1)
goto err_out;
+ if (validonly && !build_id_cache__valid_id(sbuild_id))
+ continue;
if (strlist__add(bidlist, sbuild_id) < 0)
goto err_out;
}
diff --git a/tools/perf/util/build-id.h b/tools/perf/util/build-id.h
index b742e27..64e740f 100644
--- a/tools/perf/util/build-id.h
+++ b/tools/perf/util/build-id.h
@@ -34,7 +34,7 @@ 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__cachedir(const char *sbuild_id, const char *name,
bool is_kallsyms, bool is_vdso);
-struct strlist *build_id_cache__list_all(void);
+struct strlist *build_id_cache__list_all(bool validonly);
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-file.c b/tools/perf/util/probe-file.c
index fc16b17..a5059dc 100644
--- a/tools/perf/util/probe-file.c
+++ b/tools/perf/util/probe-file.c
@@ -808,7 +808,7 @@ int probe_cache__show_all_caches(struct strfilter *filter)
pr_debug("list cache with filter: %s\n", buf);
free(buf);

- bidlist = build_id_cache__list_all();
+ bidlist = build_id_cache__list_all(true);
if (!bidlist) {
pr_debug("Failed to get buildids: %d\n", errno);
return -EINVAL;