[tip:perf/core] perf evsel: Support event groups

tip-bot for Arnaldo Carvalho de Melo
2011-01-26T07:15:39Z

Commit-ID: f08199d314458610d4ca52f8e86e0a4ec7a7bc54
Gitweb: http://git.kernel.org/tip/f08199d314458610d4ca52f8e86e0a4ec7a7bc54
Author: Arnaldo Carvalho de Melo <acme@redhat.com>
AuthorDate: Tue, 11 Jan 2011 23:42:19 -0200
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Sat, 22 Jan 2011 19:56:28 -0200

perf evsel: Support event groups

The perf_evsel__open now have an extra boolean argument specifying if
event grouping is desired.

The first file descriptor created on a CPU becomes the group leader.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/builtin-stat.c | 4 ++--
tools/perf/builtin-test.c | 4 ++--
tools/perf/util/evsel.c | 27 +++++++++++++++++----------
tools/perf/util/evsel.h | 10 ++++++----
4 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index da90902..b5fe522 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -169,7 +169,7 @@ static int create_perf_stat_counter(struct perf_evsel *evsel)
PERF_FORMAT_TOTAL_TIME_RUNNING;

if (system_wide)
- return perf_evsel__open_per_cpu(evsel, cpus);
+ return perf_evsel__open_per_cpu(evsel, cpus, false);

attr->inherit = !no_inherit;
if (target_pid == -1 && target_tid == -1) {
@@ -177,7 +177,7 @@ static int create_perf_stat_counter(struct perf_evsel *evsel)
attr->enable_on_exec = 1;
}

- return perf_evsel__open_per_thread(evsel, threads);
+ return perf_evsel__open_per_thread(evsel, threads, false);
}

/*
diff --git a/tools/perf/builtin-test.c b/tools/perf/builtin-test.c
index 5dcdba6..4282d67 100644
--- a/tools/perf/builtin-test.c
+++ b/tools/perf/builtin-test.c
@@ -289,7 +289,7 @@ static int test__open_syscall_event(void)
goto out_thread_map_delete;
}

- if (perf_evsel__open_per_thread(evsel, threads) < 0) {
+ if (perf_evsel__open_per_thread(evsel, threads, false) < 0) {
pr_debug("failed to open counter: %s, "
"tweak /proc/sys/kernel/perf_event_paranoid?\n",
strerror(errno));
@@ -364,7 +364,7 @@ static int test__open_syscall_event_on_all_cpus(void)
goto out_thread_map_delete;
}

- if (perf_evsel__open(evsel, cpus, threads) < 0) {
+ if (perf_evsel__open(evsel, cpus, threads, false) < 0) {
pr_debug("failed to open counter: %s, "
"tweak /proc/sys/kernel/perf_event_paranoid?\n",
strerror(errno));
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index f5cfed6..da473ec 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -128,7 +128,7 @@ int __perf_evsel__read(struct perf_evsel *evsel,
}

static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
- struct thread_map *threads)
+ struct thread_map *threads, bool group)
{
int cpu, thread;

@@ -137,12 +137,18 @@ static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
return -1;

for (cpu = 0; cpu < cpus->nr; cpu++) {
+ int group_fd = -1;
+
for (thread = 0; thread < threads->nr; thread++) {
FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
threads->map[thread],
- cpus->map[cpu], -1, 0);
+ cpus->map[cpu],
+ group_fd, 0);
if (FD(evsel, cpu, thread) < 0)
goto out_close;
+
+ if (group && group_fd == -1)
+ group_fd = FD(evsel, cpu, thread);
}
}

@@ -175,10 +181,9 @@ static struct {
.threads = { -1, },
};

-int perf_evsel__open(struct perf_evsel *evsel,
- struct cpu_map *cpus, struct thread_map *threads)
+int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
+ struct thread_map *threads, bool group)
{
-
if (cpus == NULL) {
/* Work around old compiler warnings about strict aliasing */
cpus = &empty_cpu_map.map;
@@ -187,15 +192,17 @@ int perf_evsel__open(struct perf_evsel *evsel,
if (threads == NULL)
threads = &empty_thread_map.map;

- return __perf_evsel__open(evsel, cpus, threads);
+ return __perf_evsel__open(evsel, cpus, threads, group);
}

-int perf_evsel__open_per_cpu(struct perf_evsel *evsel, struct cpu_map *cpus)
+int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
+ struct cpu_map *cpus, bool group)
{
- return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
+ return __perf_evsel__open(evsel, cpus, &empty_thread_map.map, group);
}

-int perf_evsel__open_per_thread(struct perf_evsel *evsel, struct thread_map *threads)
+int perf_evsel__open_per_thread(struct perf_evsel *evsel,
+ struct thread_map *threads, bool group)
{
- return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
+ return __perf_evsel__open(evsel, &empty_cpu_map.map, threads, group);
}
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index b2d755f..0962b50 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -45,10 +45,12 @@ int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus);
void perf_evsel__free_fd(struct perf_evsel *evsel);
void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads);

-int perf_evsel__open_per_cpu(struct perf_evsel *evsel, struct cpu_map *cpus);
-int perf_evsel__open_per_thread(struct perf_evsel *evsel, struct thread_map *threads);
-int perf_evsel__open(struct perf_evsel *evsel,
- struct cpu_map *cpus, struct thread_map *threads);
+int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
+ struct cpu_map *cpus, bool group);
+int perf_evsel__open_per_thread(struct perf_evsel *evsel,
+ struct thread_map *threads, bool group);
+int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
+ struct thread_map *threads, bool group);

#define perf_evsel__match(evsel, t, c) \
(evsel->attr.type == PERF_TYPE_##t && \