[tip:perf/core] perf stat: Create events as disabled

[tip-bot for Jiri Olsa]

Commit-ID:  67ccdecd09cac818146b1e153ff901cb67570012
Gitweb: http://git.kernel.org/tip/67ccdecd09cac818146b1e153ff901cb67570012
Author: Jiri Olsa 
AuthorDate: Thu, 3 Dec 2015 10:06:44 +0100
Committer:  Arnaldo Carvalho de Melo 
CommitDate: Mon, 7 Dec 2015 18:12:59 -0300

perf stat: Create events as disabled

Currently we have 2 kinds of stat counters based on when the event is
enabled:

  1) tracee command events, which are enable once the
 tracee executes exec syscall (enable_on_exec bit)
  2) all other events which get alive within the
 perf_event_open syscall

And 2) case could raise a problem in case we want additional filter to
be attached for event. In this case we want the event to be enabled
after it's configured with filter.

Changing the behaviour of 2) events, so they all are created as disabled
(disabled bit). Adding extra enable call to make them alive once they
finish setup.

Signed-off-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: 
http://lkml.kernel.org/r/1449133606-14429-6-git-send-email-jo...@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
---
 tools/perf/builtin-stat.c | 25 +++--
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 8ca40de..2e70610 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -168,11 +168,18 @@ static int create_perf_stat_counter(struct perf_evsel 
*evsel)
attr->sample_period = 0;
attr->sample_type   = 0;
 
+   /*
+* Disabling all counters initially, they will be enabled
+* either manually by us or by kernel via enable_on_exec
+* set later.
+*/
+   if (perf_evsel__is_group_leader(evsel))
+   attr->disabled = 1;
+
if (target__has_cpu())
return perf_evsel__open_per_cpu(evsel, perf_evsel__cpus(evsel));
 
if (!target__has_task() && perf_evsel__is_group_leader(evsel)) {
-   attr->disabled = 1;
if (!initial_delay)
attr->enable_on_exec = 1;
}
@@ -251,12 +258,18 @@ static void process_interval(void)
print_counters(, 0, NULL);
 }
 
-static void handle_initial_delay(void)
+static void enable_counters(void)
 {
-   if (initial_delay) {
+   if (initial_delay)
usleep(initial_delay * 1000);
+
+   /*
+* We need to enable counters only if:
+* - we don't have tracee (attaching to task or cpu)
+* - we have initial delay configured
+*/
+   if (!target__none() || initial_delay)
perf_evlist__enable(evsel_list);
-   }
 }
 
 static volatile int workload_exec_errno;
@@ -353,7 +366,7 @@ static int __run_perf_stat(int argc, const char **argv)
 
if (forks) {
perf_evlist__start_workload(evsel_list);
-   handle_initial_delay();
+   enable_counters();
 
if (interval) {
while (!waitpid(child_pid, , WNOHANG)) {
@@ -372,7 +385,7 @@ static int __run_perf_stat(int argc, const char **argv)
if (WIFSIGNALED(status))
psignal(WTERMSIG(status), argv[0]);
} else {
-   handle_initial_delay();
+   enable_counters();
while (!done) {
nanosleep(, NULL);
if (interval)
--
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[tip:perf/core] perf stat: Create events as disabled

[tip-bot for Jiri Olsa]

Commit-ID:  67ccdecd09cac818146b1e153ff901cb67570012
Gitweb: http://git.kernel.org/tip/67ccdecd09cac818146b1e153ff901cb67570012
Author: Jiri Olsa 
AuthorDate: Thu, 3 Dec 2015 10:06:44 +0100
Committer:  Arnaldo Carvalho de Melo 
CommitDate: Mon, 7 Dec 2015 18:12:59 -0300

perf stat: Create events as disabled

Currently we have 2 kinds of stat counters based on when the event is
enabled:

  1) tracee command events, which are enable once the
 tracee executes exec syscall (enable_on_exec bit)
  2) all other events which get alive within the
 perf_event_open syscall

And 2) case could raise a problem in case we want additional filter to
be attached for event. In this case we want the event to be enabled
after it's configured with filter.

Changing the behaviour of 2) events, so they all are created as disabled
(disabled bit). Adding extra enable call to make them alive once they
finish setup.

Signed-off-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: 
http://lkml.kernel.org/r/1449133606-14429-6-git-send-email-jo...@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
---
 tools/perf/builtin-stat.c | 25 +++--
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 8ca40de..2e70610 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -168,11 +168,18 @@ static int create_perf_stat_counter(struct perf_evsel 
*evsel)
attr->sample_period = 0;
attr->sample_type   = 0;
 
+   /*
+* Disabling all counters initially, they will be enabled
+* either manually by us or by kernel via enable_on_exec
+* set later.
+*/
+   if (perf_evsel__is_group_leader(evsel))
+   attr->disabled = 1;
+
if (target__has_cpu())
return perf_evsel__open_per_cpu(evsel, perf_evsel__cpus(evsel));
 
if (!target__has_task() && perf_evsel__is_group_leader(evsel)) {
-   attr->disabled = 1;
if (!initial_delay)
attr->enable_on_exec = 1;
}
@@ -251,12 +258,18 @@ static void process_interval(void)
print_counters(, 0, NULL);
 }
 
-static void handle_initial_delay(void)
+static void enable_counters(void)
 {
-   if (initial_delay) {
+   if (initial_delay)
usleep(initial_delay * 1000);
+
+   /*
+* We need to enable counters only if:
+* - we don't have tracee (attaching to task or cpu)
+* - we have initial delay configured
+*/
+   if (!target__none() || initial_delay)
perf_evlist__enable(evsel_list);
-   }
 }
 
 static volatile int workload_exec_errno;
@@ -353,7 +366,7 @@ static int __run_perf_stat(int argc, const char **argv)
 
if (forks) {
perf_evlist__start_workload(evsel_list);
-   handle_initial_delay();
+   enable_counters();
 
if (interval) {
while (!waitpid(child_pid, , WNOHANG)) {
@@ -372,7 +385,7 @@ static int __run_perf_stat(int argc, const char **argv)
if (WIFSIGNALED(status))
psignal(WTERMSIG(status), argv[0]);
} else {
-   handle_initial_delay();
+   enable_counters();
while (!done) {
nanosleep(, NULL);
if (interval)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/