[tip:perf/urgent] perf evsel: Disable write_backward for leader sampling group events

[tip-bot for Jiri Olsa]

Commit-ID:  e9add8bac6c69edb4bf391e537faa659b2ed70d2
Gitweb: https://git.kernel.org/tip/e9add8bac6c69edb4bf391e537faa659b2ed70d2
Author: Jiri Olsa 
AuthorDate: Mon, 23 Apr 2018 11:08:19 +0200
Committer:  Arnaldo Carvalho de Melo 
CommitDate: Mon, 23 Apr 2018 11:21:56 -0300

perf evsel: Disable write_backward for leader sampling group events

.. and other related fields that do not need to be enabled
for events that have sampling leader.

It fixes the perf top usage Ingo reported broken:

  # perf top -e '{cycles,msr/aperf/}:S'

The 'msr/aperf/' event is configured for write_back sampling, which is
not allowed by the MSR PMU, so it fails to create the event.

Adjusting related attr test.

Reported-by: Ingo Molnar 
Signed-off-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: David Ahern 
Cc: Kan Liang 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20180423090823.32309-6-jo...@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
---
 tools/perf/tests/attr/test-record-group-sampling | 3 +++
 tools/perf/util/evsel.c  | 7 +--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/tools/perf/tests/attr/test-record-group-sampling 
b/tools/perf/tests/attr/test-record-group-sampling
index f906b793196f..8a33ca4f9e1f 100644
--- a/tools/perf/tests/attr/test-record-group-sampling
+++ b/tools/perf/tests/attr/test-record-group-sampling
@@ -35,3 +35,6 @@ inherit=0
 # sampling disabled
 sample_freq=0
 sample_period=0
+freq=0
+write_backward=0
+sample_id_all=0
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 7eb1e9850abf..26bdeecc0452 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -930,8 +930,11 @@ void perf_evsel__config(struct perf_evsel *evsel, struct 
record_opts *opts,
 * than leader in case leader 'leads' the sampling.
 */
if ((leader != evsel) && leader->sample_read) {
-   attr->sample_freq   = 0;
-   attr->sample_period = 0;
+   attr->freq   = 0;
+   attr->sample_freq= 0;
+   attr->sample_period  = 0;
+   attr->write_backward = 0;
+   attr->sample_id_all  = 0;
}
 
if (opts->no_samples)

[tip:perf/urgent] perf evsel: Disable write_backward for leader sampling group events

[tip-bot for Jiri Olsa]

Commit-ID:  e9add8bac6c69edb4bf391e537faa659b2ed70d2
Gitweb: https://git.kernel.org/tip/e9add8bac6c69edb4bf391e537faa659b2ed70d2
Author: Jiri Olsa 
AuthorDate: Mon, 23 Apr 2018 11:08:19 +0200
Committer:  Arnaldo Carvalho de Melo 
CommitDate: Mon, 23 Apr 2018 11:21:56 -0300

perf evsel: Disable write_backward for leader sampling group events

.. and other related fields that do not need to be enabled
for events that have sampling leader.

It fixes the perf top usage Ingo reported broken:

  # perf top -e '{cycles,msr/aperf/}:S'

The 'msr/aperf/' event is configured for write_back sampling, which is
not allowed by the MSR PMU, so it fails to create the event.

Adjusting related attr test.

Reported-by: Ingo Molnar 
Signed-off-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: David Ahern 
Cc: Kan Liang 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20180423090823.32309-6-jo...@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
---
 tools/perf/tests/attr/test-record-group-sampling | 3 +++
 tools/perf/util/evsel.c  | 7 +--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/tools/perf/tests/attr/test-record-group-sampling 
b/tools/perf/tests/attr/test-record-group-sampling
index f906b793196f..8a33ca4f9e1f 100644
--- a/tools/perf/tests/attr/test-record-group-sampling
+++ b/tools/perf/tests/attr/test-record-group-sampling
@@ -35,3 +35,6 @@ inherit=0
 # sampling disabled
 sample_freq=0
 sample_period=0
+freq=0
+write_backward=0
+sample_id_all=0
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 7eb1e9850abf..26bdeecc0452 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -930,8 +930,11 @@ void perf_evsel__config(struct perf_evsel *evsel, struct 
record_opts *opts,
 * than leader in case leader 'leads' the sampling.
 */
if ((leader != evsel) && leader->sample_read) {
-   attr->sample_freq   = 0;
-   attr->sample_period = 0;
+   attr->freq   = 0;
+   attr->sample_freq= 0;
+   attr->sample_period  = 0;
+   attr->write_backward = 0;
+   attr->sample_id_all  = 0;
}
 
if (opts->no_samples)