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Author	SHA1	Message	Date
Jiri Olsa	82bf311e15	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>	2017-07-26 14:25:44 -03:00
Jiri Olsa	d809560b36	perf stat: Move perf_counts struct and functions into separate object Moving 'struct perf_counts' and associated functions into separate object, so we could remove stat.c object dependency from python build. It makes the python code to build properly, because it fails to load due to missing stat-shadow.c object dependency if some patches from Kan Liang are applied. So apply this one, then Kan's. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/20150807105103.GB8624@krava.brq.redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>	2015-08-08 14:16:49 -03:00

Author

SHA1

Message

Date

Jiri Olsa

82bf311e15

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>

2017-07-26 14:25:44 -03:00

Jiri Olsa

d809560b36

perf stat: Move perf_counts struct and functions into separate object

Moving 'struct perf_counts' and associated functions into separate
object, so we could remove stat.c object dependency from python build.

It makes the python code to build properly, because it fails to load due
to missing stat-shadow.c object dependency if some patches from Kan
Liang are applied.

So apply this one, then Kan's.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20150807105103.GB8624@krava.brq.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2015-08-08 14:16:49 -03:00

2 Commits