diff options
author | Song Liu <[email protected]> | 2018-03-05 21:55:04 -0800 |
---|---|---|
committer | Ingo Molnar <[email protected]> | 2018-03-09 08:03:02 +0100 |
commit | bd903afeb504db5655a45bb4cf86f38be5b1bf62 (patch) | |
tree | 1b3cd44a782b5f5c47f55be5c74e95a921250a98 /tools/perf/scripts/python/export-to-postgresql.py | |
parent | 629ae2ee73e225fa7dcce581c005d773b0190dcc (diff) |
perf/core: Fix ctx_event_type in ctx_resched()
In ctx_resched(), EVENT_FLEXIBLE should be sched_out when EVENT_PINNED is
added. However, ctx_resched() calculates ctx_event_type before checking
this condition. As a result, pinned events will NOT get higher priority
than flexible events.
The following shows this issue on an Intel CPU (where ref-cycles can
only use one hardware counter).
1. First start:
perf stat -C 0 -e ref-cycles -I 1000
2. Then, in the second console, run:
perf stat -C 0 -e ref-cycles:D -I 1000
The second perf uses pinned events, which is expected to have higher
priority. However, because it failed in ctx_resched(). It is never
run.
This patch fixes this by calculating ctx_event_type after re-evaluating
event_type.
Reported-by: Ephraim Park <[email protected]>
Signed-off-by: Song Liu <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: <[email protected]>
Cc: <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vince Weaver <[email protected]>
Fixes: 487f05e18aa4 ("perf/core: Optimize event rescheduling on active contexts")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
Diffstat (limited to 'tools/perf/scripts/python/export-to-postgresql.py')
0 files changed, 0 insertions, 0 deletions