diff options
author | Kan Liang <kan.liang@linux.intel.com> | 2018-02-12 14:20:33 -0800 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2018-03-09 08:22:21 +0100 |
commit | 5bee2cc69d986e20808c93c46f7b6aef51edd827 (patch) | |
tree | 0cbd8142873fce0940eb2f82cfb9d8627f1bcc8c | |
parent | bcfbe5c41d630ce6b74da45134cea484248b515a (diff) |
perf/x86/intel/ds: Introduce ->read() function for auto-reload events and flush the PEBS buffer there
There is no way to get exact auto-reload times and values which are needed
for event updates unless we flush the PEBS buffer.
Introduce intel_pmu_auto_reload_read() to drain the PEBS buffer for
auto reload event. To prevent races with the hardware, we can only
call drain_pebs() when the PMU is disabled.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Link: http://lkml.kernel.org/r/1518474035-21006-4-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-rw-r--r-- | arch/x86/events/intel/ds.c | 9 | ||||
-rw-r--r-- | arch/x86/events/perf_event.h | 2 |
2 files changed, 11 insertions, 0 deletions
diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c index f39a4df3a7bd..73844025adaf 100644 --- a/arch/x86/events/intel/ds.c +++ b/arch/x86/events/intel/ds.c @@ -1306,6 +1306,15 @@ get_next_pebs_record_by_bit(void *base, void *top, int bit) return NULL; } +void intel_pmu_auto_reload_read(struct perf_event *event) +{ + WARN_ON(!(event->hw.flags & PERF_X86_EVENT_AUTO_RELOAD)); + + perf_pmu_disable(event->pmu); + intel_pmu_drain_pebs_buffer(); + perf_pmu_enable(event->pmu); +} + /* * Special variant of intel_pmu_save_and_restart() for auto-reload. */ diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h index d445f0026989..91643472f385 100644 --- a/arch/x86/events/perf_event.h +++ b/arch/x86/events/perf_event.h @@ -924,6 +924,8 @@ void intel_pmu_pebs_disable_all(void); void intel_pmu_pebs_sched_task(struct perf_event_context *ctx, bool sched_in); +void intel_pmu_auto_reload_read(struct perf_event *event); + void intel_ds_init(void); void intel_pmu_lbr_sched_task(struct perf_event_context *ctx, bool sched_in); |