Messages in this thread | | | Date | Fri, 22 Nov 2019 20:33:43 +0100 | From | Jiri Olsa <> | Subject | Re: [PATCH v7] perf: Sharing PMU counters across compatible events |
| |
On Fri, Nov 15, 2019 at 03:55:04PM -0800, Song Liu wrote: > This patch tries to enable PMU sharing. When multiple perf_events are > counting the same metric, they can share the hardware PMU counter. We > call these events as "compatible events". > > The PMU sharing are limited to events within the same perf_event_context > (ctx). When a event is installed or enabled, search the ctx for compatible > events. This is implemented in perf_event_setup_dup(). One of these > compatible events are picked as the master (stored in event->dup_master). > Similarly, when the event is removed or disabled, perf_event_remove_dup() > is used to clean up sharing. > > A new state PERF_EVENT_STATE_ENABLED is introduced for the master event. > This state is used when the slave event is ACTIVE, but the master event > is not. > > On the critical paths (add, del read), sharing PMU counters doesn't > increase the complexity. Helper functions event_pmu_[add|del|read]() are > introduced to cover these cases. All these functions have O(1) time > complexity. > > Cc: Peter Zijlstra <peterz@infradead.org> > Cc: Arnaldo Carvalho de Melo <acme@redhat.com> > Cc: Jiri Olsa <jolsa@kernel.org> > Cc: Alexey Budankov <alexey.budankov@linux.intel.com> > Cc: Namhyung Kim <namhyung@kernel.org> > Cc: Tejun Heo <tj@kernel.org> > Signed-off-by: Song Liu <songliubraving@fb.com> > > --- > Changes in v7: > Major rewrite to avoid allocating extra master event.
hi, what is this based on? I can't apply it on tip/master:
Applying: perf: Sharing PMU counters across compatible events error: patch failed: include/linux/perf_event.h:722 error: include/linux/perf_event.h: patch does not apply Patch failed at 0001 perf: Sharing PMU counters across compatible events hint: Use 'git am --show-current-patch' to see the failed patch When you have resolved this problem, run "git am --continue". If you prefer to skip this patch, run "git am --skip" instead. To restore the original branch and stop patching, run "git am --abort".
also I'm getting this when trying to see/apply plain text patch:
[jolsa@dell-r440-01 linux-perf]$ git am --show-current-patch | tail =09=09for_each_sibling_event(sibling, group_leader) { =09=09=09perf_remove_from_context(sibling, 0); =09=09=09put_ctx(gctx); +=09=09=09WARN_ON_ONCE(sibling->dup_master); =09=09} =20 =09=09/* --=20 2.17.1
jirka
| |