All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCHv2 0/4] perf stat: Enable group read of counters
@ 2017-07-26 12:02 Jiri Olsa
  2017-07-26 12:02 ` [PATCH 1/3] perf tools: Add perf_evsel__read_size function Jiri Olsa
                   ` (2 more replies)
  0 siblings, 3 replies; 7+ messages in thread
From: Jiri Olsa @ 2017-07-26 12:02 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo
  Cc: lkml, Ingo Molnar, Peter Zijlstra, Alexander Shishkin,
	Namhyung Kim, David Ahern, Andi Kleen

hi,
sending changes to enable group read of perf counters
for perf stat command. It allows us to read whole group
of counters within single read syscall.

v2 changes:
  - fixed release segfault reported by Arnaldo
  - rebased to latest Arnaldo's perf/core
  - patch 1 already merged in

Also available in here:
  git://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
  perf/stat_group

Not sure why we haven't supported yet, but anyway it was
unavailable for some time due to a bug which was fixed
just recently via:
  ba5213ae6b88 ("perf/core: Correct event creation with PERF_FORMAT_GROUP")

thanks,
jirka


---
Jiri Olsa (3):
      perf tools: Add perf_evsel__read_size function
      perf tools: Add perf_evsel__read_counter function
      perf stat: Use group read for event groups

 tools/perf/builtin-stat.c |  30 ++++++++++++++++++++---
 tools/perf/util/counts.h  |   1 +
 tools/perf/util/evsel.c   | 139 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 tools/perf/util/evsel.h   |   2 ++
 tools/perf/util/stat.c    |   4 +++
 tools/perf/util/stat.h    |   5 ++--
 6 files changed, 175 insertions(+), 6 deletions(-)

^ permalink raw reply	[flat|nested] 7+ messages in thread
* [PATCH 1/3] perf tools: Add perf_evsel__read_size function
  2017-07-26 12:02 [PATCHv2 0/4] perf stat: Enable group read of counters Jiri Olsa
@ 2017-07-26 12:02 ` Jiri Olsa
  2017-07-30  9:38   ` [tip:perf/core] " tip-bot for Jiri Olsa
  2017-07-26 12:02 ` [PATCH 2/3] perf tools: Add perf_evsel__read_counter function Jiri Olsa
  2017-07-26 12:02 ` [PATCH 3/3] perf stat: Use group read for event groups Jiri Olsa
  2 siblings, 1 reply; 7+ messages in thread
From: Jiri Olsa @ 2017-07-26 12:02 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo
  Cc: lkml, Ingo Molnar, Peter Zijlstra, Alexander Shishkin,
	Namhyung Kim, David Ahern, Andi Kleen

Currently we use the size of struct perf_counts_values
to read the event, which prevents us to put any new
member to the struct.

Adding perf_evsel__read_size to return size of the
buffer needed for event read.

Link: http://lkml.kernel.org/n/tip-cfc3dmil3tlzezzxtyi9f38m@git.kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 tools/perf/util/evsel.c | 29 ++++++++++++++++++++++++++++-
 1 file changed, 28 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 450b5fadf8cb..4dd0fcc06db9 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1261,15 +1261,42 @@ void perf_counts_values__scale(struct perf_counts_values *count,
 		*pscaled = scaled;
 }
 
+static int perf_evsel__read_size(struct perf_evsel *evsel)
+{
+	u64 read_format = evsel->attr.read_format;
+	int entry = sizeof(u64); /* value */
+	int size = 0;
+	int nr = 1;
+
+	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+		size += sizeof(u64);
+
+	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+		size += sizeof(u64);
+
+	if (read_format & PERF_FORMAT_ID)
+		entry += sizeof(u64);
+
+	if (read_format & PERF_FORMAT_GROUP) {
+		nr = evsel->nr_members;
+		size += sizeof(u64);
+	}
+
+	size += entry * nr;
+	return size;
+}
+
 int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread,
 		     struct perf_counts_values *count)
 {
+	size_t size = perf_evsel__read_size(evsel);
+
 	memset(count, 0, sizeof(*count));
 
 	if (FD(evsel, cpu, thread) < 0)
 		return -EINVAL;
 
-	if (readn(FD(evsel, cpu, thread), count, sizeof(*count)) <= 0)
+	if (readn(FD(evsel, cpu, thread), count->values, size) <= 0)
 		return -errno;
 
 	return 0;
-- 
2.9.4

^ permalink raw reply related	[flat|nested] 7+ messages in thread
* [PATCH 2/3] perf tools: Add perf_evsel__read_counter function
  2017-07-26 12:02 [PATCHv2 0/4] perf stat: Enable group read of counters Jiri Olsa
  2017-07-26 12:02 ` [PATCH 1/3] perf tools: Add perf_evsel__read_size function Jiri Olsa
@ 2017-07-26 12:02 ` Jiri Olsa
  2017-07-30  9:38   ` [tip:perf/core] perf evsel: Add read_counter() tip-bot for Jiri Olsa
  2017-07-26 12:02 ` [PATCH 3/3] perf stat: Use group read for event groups Jiri Olsa
  2 siblings, 1 reply; 7+ messages in thread
From: Jiri Olsa @ 2017-07-26 12:02 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo
  Cc: lkml, Ingo Molnar, Peter Zijlstra, Alexander Shishkin,
	Namhyung Kim, David Ahern, Andi Kleen

Adding perf_evsel__read_counter function to read single or
group counter. After calling this function the counter's
evsel::counts struct is filled with values for the counter
and member of its group if there are any.

Link: http://lkml.kernel.org/n/tip-itsuxdyt7rp4mvij1t6k7bcl@git.kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 tools/perf/util/evsel.c | 100 ++++++++++++++++++++++++++++++++++++++++++++++++
 tools/perf/util/evsel.h |   2 +
 tools/perf/util/stat.c  |   4 ++
 tools/perf/util/stat.h  |   5 ++-
 4 files changed, 109 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 4dd0fcc06db9..89aecf3a35c7 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1302,6 +1302,106 @@ int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread,
 	return 0;
 }
 
+static int
+perf_evsel__read_one(struct perf_evsel *evsel, int cpu, int thread)
+{
+	struct perf_counts_values *count = perf_counts(evsel->counts, cpu, thread);
+
+	return perf_evsel__read(evsel, cpu, thread, count);
+}
+
+static void
+perf_evsel__set_count(struct perf_evsel *counter, int cpu, int thread,
+		      u64 val, u64 ena, u64 run)
+{
+	struct perf_counts_values *count;
+
+	count = perf_counts(counter->counts, cpu, thread);
+
+	count->val    = val;
+	count->ena    = ena;
+	count->run    = run;
+}
+
+static int
+perf_evsel__process_group_data(struct perf_evsel *leader,
+			       int cpu, int thread, u64 *data)
+{
+	u64 read_format = leader->attr.read_format;
+	struct sample_read_value *v;
+	u64 nr, ena = 0, run = 0, i;
+
+	nr = *data++;
+
+	if (nr != (u64) leader->nr_members)
+		return -EINVAL;
+
+	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+		ena = *data++;
+
+	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+		run = *data++;
+
+	v = (struct sample_read_value *) data;
+
+	perf_evsel__set_count(leader, cpu, thread,
+			      v[0].value, ena, run);
+
+	for (i = 1; i < nr; i++) {
+		struct perf_evsel *counter;
+
+		counter = perf_evlist__id2evsel(leader->evlist, v[i].id);
+		if (!counter)
+			return -EINVAL;
+
+		perf_evsel__set_count(counter, cpu, thread,
+				      v[i].value, ena, run);
+	}
+
+	return 0;
+}
+
+static int
+perf_evsel__read_group(struct perf_evsel *leader, int cpu, int thread)
+{
+	struct perf_stat_evsel *ps = leader->priv;
+	u64 read_format = leader->attr.read_format;
+	int size = perf_evsel__read_size(leader);
+	u64 *data = ps->group_data;
+
+	if (!(read_format & PERF_FORMAT_ID))
+		return -EINVAL;
+
+	if (!perf_evsel__is_group_leader(leader))
+		return -EINVAL;
+
+	if (!data) {
+		data = zalloc(size);
+		if (!data)
+			return -ENOMEM;
+
+		ps->group_data = data;
+	}
+
+	if (FD(leader, cpu, thread) < 0)
+		return -EINVAL;
+
+	if (readn(FD(leader, cpu, thread), data, size) <= 0)
+		return -errno;
+
+	return perf_evsel__process_group_data(leader, cpu, thread, data);
+}
+
+int perf_evsel__read_counter(struct perf_evsel *evsel, int cpu, int thread)
+{
+	u64 read_format = evsel->attr.read_format;
+
+	if (read_format & PERF_FORMAT_GROUP)
+		return perf_evsel__read_group(evsel, cpu, thread);
+	else
+		return perf_evsel__read_one(evsel, cpu, thread);
+}
+
 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
 			      int cpu, int thread, bool scale)
 {
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index fb40ca3c6519..de03c18daaf0 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -299,6 +299,8 @@ static inline bool perf_evsel__match2(struct perf_evsel *e1,
 int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread,
 		     struct perf_counts_values *count);
 
+int perf_evsel__read_counter(struct perf_evsel *evsel, int cpu, int thread);
+
 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
 			      int cpu, int thread, bool scale);
 
diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c
index 53b9a994a3dc..35e9848734d6 100644
--- a/tools/perf/util/stat.c
+++ b/tools/perf/util/stat.c
@@ -128,6 +128,10 @@ static int perf_evsel__alloc_stat_priv(struct perf_evsel *evsel)
 
 static void perf_evsel__free_stat_priv(struct perf_evsel *evsel)
 {
+	struct perf_stat_evsel *ps = evsel->priv;
+
+	if (ps)
+		free(ps->group_data);
 	zfree(&evsel->priv);
 }
 
diff --git a/tools/perf/util/stat.h b/tools/perf/util/stat.h
index 7522bf10b03e..eacaf958e19d 100644
--- a/tools/perf/util/stat.h
+++ b/tools/perf/util/stat.h
@@ -28,8 +28,9 @@ enum perf_stat_evsel_id {
 };
 
 struct perf_stat_evsel {
-	struct stats		res_stats[3];
-	enum perf_stat_evsel_id	id;
+	struct stats		 res_stats[3];
+	enum perf_stat_evsel_id	 id;
+	u64			*group_data;
 };
 
 enum aggr_mode {
-- 
2.9.4

^ permalink raw reply related	[flat|nested] 7+ messages in thread
* [PATCH 3/3] perf stat: Use group read for event groups
  2017-07-26 12:02 [PATCHv2 0/4] perf stat: Enable group read of counters Jiri Olsa
  2017-07-26 12:02 ` [PATCH 1/3] perf tools: Add perf_evsel__read_size function Jiri Olsa
  2017-07-26 12:02 ` [PATCH 2/3] perf tools: Add perf_evsel__read_counter function Jiri Olsa
@ 2017-07-26 12:02 ` Jiri Olsa
  2017-07-30  9:39   ` [tip:perf/core] " tip-bot for Jiri Olsa
  2 siblings, 1 reply; 7+ messages in thread
From: Jiri Olsa @ 2017-07-26 12:02 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo
  Cc: lkml, Ingo Molnar, Peter Zijlstra, Alexander Shishkin,
	Namhyung Kim, David Ahern, Andi Kleen

Make perf stat use  group read if there  are groups
defined. The group read will get the values for all
member of groups within a single syscall instead of
calling read syscall for every event.

We can see considerable less amount of kernel cycles
spent on single group read, than reading each event
separately, like for following perf stat command:

  # perf stat -e {cycles,instructions} -I 10 -a sleep 1

Monitored with "perf stat -r 5 -e '{cycles:u,cycles:k}'"

Before:

        24,325,676      cycles:u
       297,040,775      cycles:k

       1.038554134 seconds time elapsed

After:
        25,034,418      cycles:u
       158,256,395      cycles:k

       1.036864497 seconds time elapsed

The perf_evsel__open fallback changes contributed by Andi Kleen.

Link: http://lkml.kernel.org/n/tip-b6g8qarwvptr81cqdtfst59u@git.kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 tools/perf/builtin-stat.c | 30 +++++++++++++++++++++++++++---
 tools/perf/util/counts.h  |  1 +
 tools/perf/util/evsel.c   | 10 ++++++++++
 3 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 48ac53b199fc..866da7aa54bf 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -213,10 +213,20 @@ static void perf_stat__reset_stats(void)
 static int create_perf_stat_counter(struct perf_evsel *evsel)
 {
 	struct perf_event_attr *attr = &evsel->attr;
+	struct perf_evsel *leader = evsel->leader;
 
-	if (stat_config.scale)
+	if (stat_config.scale) {
 		attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
 				    PERF_FORMAT_TOTAL_TIME_RUNNING;
+	}
+
+	/*
+	 * The event is part of non trivial group, let's enable
+	 * the group read (for leader) and ID retrieval for all
+	 * members.
+	 */
+	if (leader->nr_members > 1)
+		attr->read_format |= PERF_FORMAT_ID|PERF_FORMAT_GROUP;
 
 	attr->inherit = !no_inherit;
 
@@ -333,13 +343,21 @@ static int read_counter(struct perf_evsel *counter)
 			struct perf_counts_values *count;
 
 			count = perf_counts(counter->counts, cpu, thread);
-			if (perf_evsel__read(counter, cpu, thread, count)) {
+
+			/*
+			 * The leader's group read loads data into its group members
+			 * (via perf_evsel__read_counter) and sets threir count->loaded.
+			 */
+			if (!count->loaded &&
+			    perf_evsel__read_counter(counter, cpu, thread)) {
 				counter->counts->scaled = -1;
 				perf_counts(counter->counts, cpu, thread)->ena = 0;
 				perf_counts(counter->counts, cpu, thread)->run = 0;
 				return -1;
 			}
 
+			count->loaded = false;
+
 			if (STAT_RECORD) {
 				if (perf_evsel__write_stat_event(counter, cpu, thread, count)) {
 					pr_err("failed to write stat event\n");
@@ -559,6 +577,11 @@ static int store_counter_ids(struct perf_evsel *counter)
 	return __store_counter_ids(counter, cpus, threads);
 }
 
+static bool perf_evsel__should_store_id(struct perf_evsel *counter)
+{
+	return STAT_RECORD || counter->attr.read_format & PERF_FORMAT_ID;
+}
+
 static int __run_perf_stat(int argc, const char **argv)
 {
 	int interval = stat_config.interval;
@@ -631,7 +654,8 @@ static int __run_perf_stat(int argc, const char **argv)
 		if (l > unit_width)
 			unit_width = l;
 
-		if (STAT_RECORD && store_counter_ids(counter))
+		if (perf_evsel__should_store_id(counter) &&
+		    store_counter_ids(counter))
 			return -1;
 	}
 
diff --git a/tools/perf/util/counts.h b/tools/perf/util/counts.h
index 34d8baaf558a..cb45a6aecf9d 100644
--- a/tools/perf/util/counts.h
+++ b/tools/perf/util/counts.h
@@ -12,6 +12,7 @@ struct perf_counts_values {
 		};
 		u64 values[3];
 	};
+	bool	loaded;
 };
 
 struct perf_counts {
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 89aecf3a35c7..3735c9e0080d 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -49,6 +49,7 @@ static struct {
 	bool clockid_wrong;
 	bool lbr_flags;
 	bool write_backward;
+	bool group_read;
 } perf_missing_features;
 
 static clockid_t clockid;
@@ -1321,6 +1322,7 @@ perf_evsel__set_count(struct perf_evsel *counter, int cpu, int thread,
 	count->val    = val;
 	count->ena    = ena;
 	count->run    = run;
+	count->loaded = true;
 }
 
 static int
@@ -1677,6 +1679,8 @@ int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
 	if (perf_missing_features.lbr_flags)
 		evsel->attr.branch_sample_type &= ~(PERF_SAMPLE_BRANCH_NO_FLAGS |
 				     PERF_SAMPLE_BRANCH_NO_CYCLES);
+	if (perf_missing_features.group_read && evsel->attr.inherit)
+		evsel->attr.read_format &= ~(PERF_FORMAT_GROUP|PERF_FORMAT_ID);
 retry_sample_id:
 	if (perf_missing_features.sample_id_all)
 		evsel->attr.sample_id_all = 0;
@@ -1832,6 +1836,12 @@ int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
 		perf_missing_features.lbr_flags = true;
 		pr_debug2("switching off branch sample type no (cycles/flags)\n");
 		goto fallback_missing_features;
+	} else if (!perf_missing_features.group_read &&
+		    evsel->attr.inherit &&
+		   (evsel->attr.read_format & PERF_FORMAT_GROUP)) {
+		perf_missing_features.group_read = true;
+		pr_debug2("switching off group read\n");
+		goto fallback_missing_features;
 	}
 out_close:
 	do {
-- 
2.9.4

^ permalink raw reply related	[flat|nested] 7+ messages in thread
* [tip:perf/core] perf tools: Add perf_evsel__read_size function
  2017-07-26 12:02 ` [PATCH 1/3] perf tools: Add perf_evsel__read_size function Jiri Olsa
@ 2017-07-30  9:38   ` tip-bot for Jiri Olsa
  0 siblings, 0 replies; 7+ messages in thread
From: tip-bot for Jiri Olsa @ 2017-07-30  9:38 UTC (permalink / raw)
  To: linux-tip-commits
  Cc: namhyung, alexander.shishkin, dsahern, linux-kernel,
	a.p.zijlstra, mingo, jolsa, hpa, andi, acme, tglx

Commit-ID:  de63403bfd14ae8d613f30c9a0d415581b4cb37e
Gitweb:     http://git.kernel.org/tip/de63403bfd14ae8d613f30c9a0d415581b4cb37e
Author:     Jiri Olsa <jolsa@kernel.org>
AuthorDate: Wed, 26 Jul 2017 14:02:04 +0200
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Wed, 26 Jul 2017 14:20:28 -0300

perf tools: Add perf_evsel__read_size function

Currently we use the size of struct perf_counts_values to read the
event, which prevents us to put any new member to the struct.

Adding perf_evsel__read_size to return size of the buffer needed for
event read.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170726120206.9099-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/evsel.c | 29 ++++++++++++++++++++++++++++-
 1 file changed, 28 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 450b5fa..4dd0fcc 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1261,15 +1261,42 @@ void perf_counts_values__scale(struct perf_counts_values *count,
 		*pscaled = scaled;
 }
 
+static int perf_evsel__read_size(struct perf_evsel *evsel)
+{
+	u64 read_format = evsel->attr.read_format;
+	int entry = sizeof(u64); /* value */
+	int size = 0;
+	int nr = 1;
+
+	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+		size += sizeof(u64);
+
+	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+		size += sizeof(u64);
+
+	if (read_format & PERF_FORMAT_ID)
+		entry += sizeof(u64);
+
+	if (read_format & PERF_FORMAT_GROUP) {
+		nr = evsel->nr_members;
+		size += sizeof(u64);
+	}
+
+	size += entry * nr;
+	return size;
+}
+
 int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread,
 		     struct perf_counts_values *count)
 {
+	size_t size = perf_evsel__read_size(evsel);
+
 	memset(count, 0, sizeof(*count));
 
 	if (FD(evsel, cpu, thread) < 0)
 		return -EINVAL;
 
-	if (readn(FD(evsel, cpu, thread), count, sizeof(*count)) <= 0)
+	if (readn(FD(evsel, cpu, thread), count->values, size) <= 0)
 		return -errno;
 
 	return 0;

^ permalink raw reply related	[flat|nested] 7+ messages in thread
* [tip:perf/core] perf evsel: Add read_counter()
  2017-07-26 12:02 ` [PATCH 2/3] perf tools: Add perf_evsel__read_counter function Jiri Olsa
@ 2017-07-30  9:38   ` tip-bot for Jiri Olsa
  0 siblings, 0 replies; 7+ messages in thread
From: tip-bot for Jiri Olsa @ 2017-07-30  9:38 UTC (permalink / raw)
  To: linux-tip-commits
  Cc: a.p.zijlstra, dsahern, hpa, mingo, andi, alexander.shishkin,
	tglx, linux-kernel, namhyung, jolsa, acme

Commit-ID:  f7794d525447f1e4e4b2228dd29dba084005e6bf
Gitweb:     http://git.kernel.org/tip/f7794d525447f1e4e4b2228dd29dba084005e6bf
Author:     Jiri Olsa <jolsa@kernel.org>
AuthorDate: Wed, 26 Jul 2017 14:02:05 +0200
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Wed, 26 Jul 2017 14:21:59 -0300

perf evsel: Add read_counter()

Add perf_evsel__read_counter() to read single or group counter. After
calling this function the counter's evsel::counts struct is filled with
values for the counter and member of its group if there are any.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170726120206.9099-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/evsel.c | 100 ++++++++++++++++++++++++++++++++++++++++++++++++
 tools/perf/util/evsel.h |   2 +
 tools/perf/util/stat.c  |   4 ++
 tools/perf/util/stat.h  |   5 ++-
 4 files changed, 109 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 4dd0fcc..89aecf3 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1302,6 +1302,106 @@ int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread,
 	return 0;
 }
 
+static int
+perf_evsel__read_one(struct perf_evsel *evsel, int cpu, int thread)
+{
+	struct perf_counts_values *count = perf_counts(evsel->counts, cpu, thread);
+
+	return perf_evsel__read(evsel, cpu, thread, count);
+}
+
+static void
+perf_evsel__set_count(struct perf_evsel *counter, int cpu, int thread,
+		      u64 val, u64 ena, u64 run)
+{
+	struct perf_counts_values *count;
+
+	count = perf_counts(counter->counts, cpu, thread);
+
+	count->val    = val;
+	count->ena    = ena;
+	count->run    = run;
+}
+
+static int
+perf_evsel__process_group_data(struct perf_evsel *leader,
+			       int cpu, int thread, u64 *data)
+{
+	u64 read_format = leader->attr.read_format;
+	struct sample_read_value *v;
+	u64 nr, ena = 0, run = 0, i;
+
+	nr = *data++;
+
+	if (nr != (u64) leader->nr_members)
+		return -EINVAL;
+
+	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+		ena = *data++;
+
+	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+		run = *data++;
+
+	v = (struct sample_read_value *) data;
+
+	perf_evsel__set_count(leader, cpu, thread,
+			      v[0].value, ena, run);
+
+	for (i = 1; i < nr; i++) {
+		struct perf_evsel *counter;
+
+		counter = perf_evlist__id2evsel(leader->evlist, v[i].id);
+		if (!counter)
+			return -EINVAL;
+
+		perf_evsel__set_count(counter, cpu, thread,
+				      v[i].value, ena, run);
+	}
+
+	return 0;
+}
+
+static int
+perf_evsel__read_group(struct perf_evsel *leader, int cpu, int thread)
+{
+	struct perf_stat_evsel *ps = leader->priv;
+	u64 read_format = leader->attr.read_format;
+	int size = perf_evsel__read_size(leader);
+	u64 *data = ps->group_data;
+
+	if (!(read_format & PERF_FORMAT_ID))
+		return -EINVAL;
+
+	if (!perf_evsel__is_group_leader(leader))
+		return -EINVAL;
+
+	if (!data) {
+		data = zalloc(size);
+		if (!data)
+			return -ENOMEM;
+
+		ps->group_data = data;
+	}
+
+	if (FD(leader, cpu, thread) < 0)
+		return -EINVAL;
+
+	if (readn(FD(leader, cpu, thread), data, size) <= 0)
+		return -errno;
+
+	return perf_evsel__process_group_data(leader, cpu, thread, data);
+}
+
+int perf_evsel__read_counter(struct perf_evsel *evsel, int cpu, int thread)
+{
+	u64 read_format = evsel->attr.read_format;
+
+	if (read_format & PERF_FORMAT_GROUP)
+		return perf_evsel__read_group(evsel, cpu, thread);
+	else
+		return perf_evsel__read_one(evsel, cpu, thread);
+}
+
 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
 			      int cpu, int thread, bool scale)
 {
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index fb40ca3..de03c18 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -299,6 +299,8 @@ static inline bool perf_evsel__match2(struct perf_evsel *e1,
 int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread,
 		     struct perf_counts_values *count);
 
+int perf_evsel__read_counter(struct perf_evsel *evsel, int cpu, int thread);
+
 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
 			      int cpu, int thread, bool scale);
 
diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c
index 53b9a99..35e9848 100644
--- a/tools/perf/util/stat.c
+++ b/tools/perf/util/stat.c
@@ -128,6 +128,10 @@ static int perf_evsel__alloc_stat_priv(struct perf_evsel *evsel)
 
 static void perf_evsel__free_stat_priv(struct perf_evsel *evsel)
 {
+	struct perf_stat_evsel *ps = evsel->priv;
+
+	if (ps)
+		free(ps->group_data);
 	zfree(&evsel->priv);
 }
 
diff --git a/tools/perf/util/stat.h b/tools/perf/util/stat.h
index 7522bf1..eacaf95 100644
--- a/tools/perf/util/stat.h
+++ b/tools/perf/util/stat.h
@@ -28,8 +28,9 @@ enum perf_stat_evsel_id {
 };
 
 struct perf_stat_evsel {
-	struct stats		res_stats[3];
-	enum perf_stat_evsel_id	id;
+	struct stats		 res_stats[3];
+	enum perf_stat_evsel_id	 id;
+	u64			*group_data;
 };
 
 enum aggr_mode {

^ permalink raw reply related	[flat|nested] 7+ messages in thread
* [tip:perf/core] perf stat: Use group read for event groups
  2017-07-26 12:02 ` [PATCH 3/3] perf stat: Use group read for event groups Jiri Olsa
@ 2017-07-30  9:39   ` tip-bot for Jiri Olsa
  0 siblings, 0 replies; 7+ messages in thread
From: tip-bot for Jiri Olsa @ 2017-07-30  9:39 UTC (permalink / raw)
  To: linux-tip-commits
  Cc: mingo, acme, hpa, andi, tglx, alexander.shishkin, linux-kernel,
	namhyung, jolsa, dsahern, a.p.zijlstra

Commit-ID:  82bf311e15d22e2fa45423b1fb4a21cf925381fe
Gitweb:     http://git.kernel.org/tip/82bf311e15d22e2fa45423b1fb4a21cf925381fe
Author:     Jiri Olsa <jolsa@kernel.org>
AuthorDate: Wed, 26 Jul 2017 14:02:06 +0200
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Wed, 26 Jul 2017 14:25:44 -0300

perf stat: Use group read for event groups

Make perf stat use  group read if there  are groups defined. The group
read will get the values for all member of groups within a single
syscall instead of calling read syscall for every event.

We can see considerable less amount of kernel cycles spent on single
group read, than reading each event separately, like for following perf
stat command:

  # perf stat -e {cycles,instructions} -I 10 -a sleep 1

Monitored with "perf stat -r 5 -e '{cycles:u,cycles:k}'"

Before:

        24,325,676      cycles:u
       297,040,775      cycles:k

       1.038554134 seconds time elapsed

After:
        25,034,418      cycles:u
       158,256,395      cycles:k

       1.036864497 seconds time elapsed

The perf_evsel__open fallback changes contributed by Andi Kleen.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170726120206.9099-4-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/builtin-stat.c | 30 +++++++++++++++++++++++++++---
 tools/perf/util/counts.h  |  1 +
 tools/perf/util/evsel.c   | 10 ++++++++++
 3 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 48ac53b..866da7a 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -213,10 +213,20 @@ static void perf_stat__reset_stats(void)
 static int create_perf_stat_counter(struct perf_evsel *evsel)
 {
 	struct perf_event_attr *attr = &evsel->attr;
+	struct perf_evsel *leader = evsel->leader;
 
-	if (stat_config.scale)
+	if (stat_config.scale) {
 		attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
 				    PERF_FORMAT_TOTAL_TIME_RUNNING;
+	}
+
+	/*
+	 * The event is part of non trivial group, let's enable
+	 * the group read (for leader) and ID retrieval for all
+	 * members.
+	 */
+	if (leader->nr_members > 1)
+		attr->read_format |= PERF_FORMAT_ID|PERF_FORMAT_GROUP;
 
 	attr->inherit = !no_inherit;
 
@@ -333,13 +343,21 @@ static int read_counter(struct perf_evsel *counter)
 			struct perf_counts_values *count;
 
 			count = perf_counts(counter->counts, cpu, thread);
-			if (perf_evsel__read(counter, cpu, thread, count)) {
+
+			/*
+			 * The leader's group read loads data into its group members
+			 * (via perf_evsel__read_counter) and sets threir count->loaded.
+			 */
+			if (!count->loaded &&
+			    perf_evsel__read_counter(counter, cpu, thread)) {
 				counter->counts->scaled = -1;
 				perf_counts(counter->counts, cpu, thread)->ena = 0;
 				perf_counts(counter->counts, cpu, thread)->run = 0;
 				return -1;
 			}
 
+			count->loaded = false;
+
 			if (STAT_RECORD) {
 				if (perf_evsel__write_stat_event(counter, cpu, thread, count)) {
 					pr_err("failed to write stat event\n");
@@ -559,6 +577,11 @@ static int store_counter_ids(struct perf_evsel *counter)
 	return __store_counter_ids(counter, cpus, threads);
 }
 
+static bool perf_evsel__should_store_id(struct perf_evsel *counter)
+{
+	return STAT_RECORD || counter->attr.read_format & PERF_FORMAT_ID;
+}
+
 static int __run_perf_stat(int argc, const char **argv)
 {
 	int interval = stat_config.interval;
@@ -631,7 +654,8 @@ try_again:
 		if (l > unit_width)
 			unit_width = l;
 
-		if (STAT_RECORD && store_counter_ids(counter))
+		if (perf_evsel__should_store_id(counter) &&
+		    store_counter_ids(counter))
 			return -1;
 	}
 
diff --git a/tools/perf/util/counts.h b/tools/perf/util/counts.h
index 34d8baa..cb45a6a 100644
--- a/tools/perf/util/counts.h
+++ b/tools/perf/util/counts.h
@@ -12,6 +12,7 @@ struct perf_counts_values {
 		};
 		u64 values[3];
 	};
+	bool	loaded;
 };
 
 struct perf_counts {
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 89aecf3..3735c9e 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -49,6 +49,7 @@ static struct {
 	bool clockid_wrong;
 	bool lbr_flags;
 	bool write_backward;
+	bool group_read;
 } perf_missing_features;
 
 static clockid_t clockid;
@@ -1321,6 +1322,7 @@ perf_evsel__set_count(struct perf_evsel *counter, int cpu, int thread,
 	count->val    = val;
 	count->ena    = ena;
 	count->run    = run;
+	count->loaded = true;
 }
 
 static int
@@ -1677,6 +1679,8 @@ fallback_missing_features:
 	if (perf_missing_features.lbr_flags)
 		evsel->attr.branch_sample_type &= ~(PERF_SAMPLE_BRANCH_NO_FLAGS |
 				     PERF_SAMPLE_BRANCH_NO_CYCLES);
+	if (perf_missing_features.group_read && evsel->attr.inherit)
+		evsel->attr.read_format &= ~(PERF_FORMAT_GROUP|PERF_FORMAT_ID);
 retry_sample_id:
 	if (perf_missing_features.sample_id_all)
 		evsel->attr.sample_id_all = 0;
@@ -1832,6 +1836,12 @@ try_fallback:
 		perf_missing_features.lbr_flags = true;
 		pr_debug2("switching off branch sample type no (cycles/flags)\n");
 		goto fallback_missing_features;
+	} else if (!perf_missing_features.group_read &&
+		    evsel->attr.inherit &&
+		   (evsel->attr.read_format & PERF_FORMAT_GROUP)) {
+		perf_missing_features.group_read = true;
+		pr_debug2("switching off group read\n");
+		goto fallback_missing_features;
 	}
 out_close:
 	do {

^ permalink raw reply related	[flat|nested] 7+ messages in thread
end of thread, other threads:[~2017-07-30  9:41 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-07-26 12:02 [PATCHv2 0/4] perf stat: Enable group read of counters Jiri Olsa
2017-07-26 12:02 ` [PATCH 1/3] perf tools: Add perf_evsel__read_size function Jiri Olsa
2017-07-30  9:38   ` [tip:perf/core] " tip-bot for Jiri Olsa
2017-07-26 12:02 ` [PATCH 2/3] perf tools: Add perf_evsel__read_counter function Jiri Olsa
2017-07-30  9:38   ` [tip:perf/core] perf evsel: Add read_counter() tip-bot for Jiri Olsa
2017-07-26 12:02 ` [PATCH 3/3] perf stat: Use group read for event groups Jiri Olsa
2017-07-30  9:39   ` [tip:perf/core] " tip-bot for Jiri Olsa

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.