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author | Jiri Olsa <jolsa@kernel.org> | 2018-02-06 19:17:57 +0100 |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2018-02-16 10:09:23 -0300 |
commit | 8614ada0be7d7be84b85c006d526a9c8f76484fa (patch) | |
tree | 758e7a5aa362a6a6849d69f6b6e5b80c28575f4c /tools/perf/builtin-report.c | |
parent | a7402c943bb4657cc0b44453177803fbead70990 (diff) | |
download | op-kernel-dev-8614ada0be7d7be84b85c006d526a9c8f76484fa.zip op-kernel-dev-8614ada0be7d7be84b85c006d526a9c8f76484fa.tar.gz |
perf report: Ask for ordered events for --tasks option
If we have the time in, keep the events in time order.
Committer notes:
Trying to be more verbose, what actual effect this will have in this particular
case?
Before and after this patch shows the artifacts:
--- /tmp/before 2018-02-06 15:40:29.536411625 -0300
+++ /tmp/after 2018-02-06 15:40:51.963403599 -0300
@@ -5,34 +5,34 @@
2540 2540 1818 | gnome-terminal-
3489 3489 2540 | bash
32433 32433 3489 | perf
- 32434 32434 32433 | perf
+ 32434 32434 32433 | make
32441 32441 32434 | make
32514 32514 32441 | make
511 511 32514 | sh
- 512 512 511 | sh
+ 512 512 511 | install
<SNIP>
We don't have 'perf' calling 'perf' calling 'make', etc, the second
'perf' actually is 'make', i.e. there was reordering of the relevant
PERF_RECORD_COMM and PERF_RECORD_FORK records.
Ditto for sh/install later on.
Look for FORK and COMM meta events, for those tids:
# perf report -D | egrep 'PERF_RECORD_(FORK|COMM)' | egrep '3243[34]'
0 14774650990679 0x1a3cd8 [0x38]: PERF_RECORD_FORK(32433:32433):(3489:3489)
1 14774652080381 0x1d6568 [0x30]: PERF_RECORD_COMM exec: perf:32433/32433
1 14774742473340 0x1dbb48 [0x38]: PERF_RECORD_FORK(32434:32434):(32433:32433)
0 14774752005779 0x1a4af8 [0x30]: PERF_RECORD_COMM exec: make:32434/32434
0 14774753997960 0x1a5578 [0x38]: PERF_RECORD_FORK(32435:32435):(32434:32434)
0 14774756070782 0x1a5618 [0x38]: PERF_RECORD_FORK(32438:32438):(32434:32434)
0 14774757772939 0x1a5680 [0x38]: PERF_RECORD_FORK(32440:32440):(32434:32434)
0 14774758230600 0x1a56e8 [0x38]: PERF_RECORD_FORK(32441:32441):(32434:32434)
#
First column is the cpu, second is the timestamp.
So they are on different CPUs, thus ring buffers, and when we don't use
the ordered_events class, we end up mixing that up, use it to take
advantage of the PERF_RECORD_FINISHED_ROUND meta events to go on
ordering the events using the PERF_SAMPLE_TIME present in the
PERF_RECORD_{FORK,COMM,EXIT,SAMPLE,etc} records in the ring buffer.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180206181813.10943-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/builtin-report.c')
-rw-r--r-- | tools/perf/builtin-report.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c index 4ad5dc6..8ef7166 100644 --- a/tools/perf/builtin-report.c +++ b/tools/perf/builtin-report.c @@ -614,6 +614,7 @@ static int stats_print(struct report *rep) static void tasks_setup(struct report *rep) { memset(&rep->tool, 0, sizeof(rep->tool)); + rep->tool.ordered_events = true; if (rep->mmaps_mode) { rep->tool.mmap = perf_event__process_mmap; rep->tool.mmap2 = perf_event__process_mmap2; |