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Groups > linux.kernel > #1528645
| From | kan.liang@intel.com |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD |
| Date | 2016-11-23 18:50 +0100 |
| Message-ID | <sGJQd-7SF-13@gated-at.bofh.it> (permalink) |
| References | <sGJQd-7SF-5@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
From: Kan Liang <kan.liang@intel.com>
A new perf record is introduced to export perf overhead information to
userspace. So we can measure the overhead of sampling directly.
To output the overhead information, it takes advantage of the existing
event log mechanism. But the overhead information is the system
overhead, not per-event overhead.
Signed-off-by: Kan Liang <kan.liang@intel.com>
---
include/linux/perf_event.h | 4 ++++
include/uapi/linux/perf_event.h | 29 +++++++++++++++++++++++++++
kernel/events/core.c | 43 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 76 insertions(+)
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 4741ecd..3a530a7 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -998,6 +998,10 @@ perf_event__output_id_sample(struct perf_event *event,
extern void
perf_log_lost_samples(struct perf_event *event, u64 lost);
+extern void
+perf_log_overhead(struct perf_event *event, u32 type,
+ struct perf_overhead_entry *entry);
+
static inline bool is_sampling_event(struct perf_event *event)
{
return event->attr.sample_period != 0;
diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index c66a485..ae571be 100644
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -862,6 +862,17 @@ enum perf_event_type {
*/
PERF_RECORD_SWITCH_CPU_WIDE = 15,
+ /*
+ * Records perf overhead
+ * struct {
+ * struct perf_event_header header;
+ * u32 type;
+ * struct perf_overhead_entry entry;
+ * struct sample_id sample_id;
+ * };
+ */
+ PERF_RECORD_OVERHEAD = 16,
+
PERF_RECORD_MAX, /* non-ABI */
};
@@ -980,4 +991,22 @@ struct perf_branch_entry {
reserved:44;
};
+enum perf_record_overhead_type {
+ PERF_OVERHEAD_MAX,
+};
+
+/*
+ * single overhead record layout:
+ *
+ * cpu: The cpu which overhead occues
+ * nr: Times of overhead happens.
+ * E.g. for NMI, nr == times of NMI handler are called.
+ * time: Total overhead cost(ns)
+ */
+struct perf_overhead_entry {
+ __u32 cpu;
+ __u64 nr;
+ __u64 time;
+};
+
#endif /* _UAPI_LINUX_PERF_EVENT_H */
diff --git a/kernel/events/core.c b/kernel/events/core.c
index ff230bb..590c399 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -7037,6 +7037,49 @@ static void perf_log_itrace_start(struct perf_event *event)
perf_output_end(&handle);
}
+
+/*
+ * Record overhead logging
+ *
+ * The overhead logged here is the system overhead, not per-event overhead.
+ * This function only take advantage of the existing event log mechanism
+ * to log the overhead record.
+ *
+ */
+void perf_log_overhead(struct perf_event *event, u32 type,
+ struct perf_overhead_entry *entry)
+{
+ struct perf_output_handle handle;
+ struct perf_sample_data sample;
+ int ret;
+
+ struct {
+ struct perf_event_header header;
+ u32 type;
+ struct perf_overhead_entry overhead;
+ } overhead_event = {
+ .header = {
+ .type = PERF_RECORD_OVERHEAD,
+ .misc = 0,
+ .size = sizeof(overhead_event),
+ },
+ };
+ overhead_event.type = type;
+ memcpy(&overhead_event.overhead, entry, sizeof(overhead_event.overhead));
+
+ perf_event_header__init_id(&overhead_event.header, &sample, event);
+ ret = perf_output_begin(&handle, event, overhead_event.header.size);
+
+ if (ret)
+ return;
+
+ perf_output_put(&handle, overhead_event);
+ perf_event__output_id_sample(event, &handle, &sample);
+
+ perf_output_end(&handle);
+ memset(entry, 0, sizeof(*entry));
+}
+
/*
* Generic event overflow handling, sampling.
*/
--
2.5.5
Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
[PATCH 00/14] export perf overheads information kan.liang@intel.com - 2016-11-23 18:50 +0100
[PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD kan.liang@intel.com - 2016-11-23 18:50 +0100
Re: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD Peter Zijlstra <peterz@infradead.org> - 2016-11-23 21:20 +0100
Re: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD Peter Zijlstra <peterz@infradead.org> - 2016-11-23 21:20 +0100
Re: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD Jiri Olsa <jolsa@redhat.com> - 2016-11-24 00:50 +0100
RE: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD "Liang, Kan" <kan.liang@intel.com> - 2016-11-24 14:50 +0100
Re: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD Peter Zijlstra <peterz@infradead.org> - 2016-11-24 15:00 +0100
RE: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD "Liang, Kan" <kan.liang@intel.com> - 2016-11-24 15:10 +0100
Re: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD Jiri Olsa <jolsa@redhat.com> - 2016-11-24 15:30 +0100
Re: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD Jiri Olsa <jolsa@redhat.com> - 2016-11-24 15:50 +0100
RE: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD "Liang, Kan" <kan.liang@intel.com> - 2016-11-24 15:50 +0100
Re: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD Andi Kleen <andi@firstfloor.org> - 2016-11-24 19:30 +0100
Re: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD Peter Zijlstra <peterz@infradead.org> - 2016-11-24 20:00 +0100
Re: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD Andi Kleen <andi@firstfloor.org> - 2016-11-24 20:10 +0100
Re: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD Peter Zijlstra <peterz@infradead.org> - 2016-11-24 20:10 +0100
[PATCH 11/14] perf tools: record write data overhead kan.liang@intel.com - 2016-11-23 18:50 +0100
Re: [PATCH 11/14] perf tools: record write data overhead Jiri Olsa <jolsa@redhat.com> - 2016-11-24 00:10 +0100
Re: [PATCH 11/14] perf tools: record write data overhead Jiri Olsa <jolsa@redhat.com> - 2016-11-24 00:20 +0100
[PATCH 04/14] perf/x86: output side-band events overhead kan.liang@intel.com - 2016-11-23 18:50 +0100
Re: [PATCH 04/14] perf/x86: output side-band events overhead Peter Zijlstra <peterz@infradead.org> - 2016-11-23 21:10 +0100
Re: [PATCH 04/14] perf/x86: output side-band events overhead Mark Rutland <mark.rutland@arm.com> - 2016-11-24 17:30 +0100
RE: [PATCH 04/14] perf/x86: output side-band events overhead "Liang, Kan" <kan.liang@intel.com> - 2016-11-24 20:50 +0100
[PATCH 07/14] perf tools: show multiplexing overhead kan.liang@intel.com - 2016-11-23 18:50 +0100
[PATCH 08/14] perf tools: show side-band events overhead kan.liang@intel.com - 2016-11-23 18:50 +0100
[PATCH 05/14] perf tools: handle PERF_RECORD_OVERHEAD record type kan.liang@intel.com - 2016-11-23 18:50 +0100
Re: [PATCH 05/14] perf tools: handle PERF_RECORD_OVERHEAD record type Jiri Olsa <jolsa@redhat.com> - 2016-11-23 23:40 +0100
Re: [PATCH 05/14] perf tools: handle PERF_RECORD_OVERHEAD record type Jiri Olsa <jolsa@redhat.com> - 2016-11-24 00:00 +0100
[PATCH 12/14] perf tools: record elapsed time kan.liang@intel.com - 2016-11-23 18:50 +0100
[PATCH 13/14] perf tools: warn on high overhead kan.liang@intel.com - 2016-11-23 18:50 +0100
Re: [PATCH 13/14] perf tools: warn on high overhead Andi Kleen <andi@firstfloor.org> - 2016-11-23 21:30 +0100
RE: [PATCH 13/14] perf tools: warn on high overhead "Liang, Kan" <kan.liang@intel.com> - 2016-11-23 23:10 +0100
[PATCH 14/14] perf script: show overhead events kan.liang@intel.com - 2016-11-23 18:50 +0100
Re: [PATCH 14/14] perf script: show overhead events Jiri Olsa <jolsa@redhat.com> - 2016-11-24 00:30 +0100
Re: [PATCH 14/14] perf script: show overhead events Jiri Olsa <jolsa@redhat.com> - 2016-11-24 00:30 +0100
Re: [PATCH 14/14] perf script: show overhead events Jiri Olsa <jolsa@redhat.com> - 2016-11-24 00:40 +0100
Re: [PATCH 14/14] perf script: show overhead events Jiri Olsa <jolsa@redhat.com> - 2016-11-24 00:40 +0100
[PATCH 03/14] perf/x86: output multiplexing overhead kan.liang@intel.com - 2016-11-23 18:50 +0100
Re: [PATCH 03/14] perf/x86: output multiplexing overhead Peter Zijlstra <peterz@infradead.org> - 2016-11-23 21:10 +0100
RE: [PATCH 03/14] perf/x86: output multiplexing overhead "Liang, Kan" <kan.liang@intel.com> - 2016-11-23 21:20 +0100
[PATCH 10/14] perf tools: introduce PERF_RECORD_USER_OVERHEAD kan.liang@intel.com - 2016-11-23 18:50 +0100
[PATCH 06/14] perf tools: show NMI overhead kan.liang@intel.com - 2016-11-23 18:50 +0100
Re: [PATCH 06/14] perf tools: show NMI overhead Jiri Olsa <jolsa@redhat.com> - 2016-11-24 00:00 +0100
Re: [PATCH 06/14] perf tools: show NMI overhead Jiri Olsa <jolsa@redhat.com> - 2016-11-24 00:00 +0100
RE: [PATCH 06/14] perf tools: show NMI overhead "Liang, Kan" <kan.liang@intel.com> - 2016-11-24 14:40 +0100
Re: [PATCH 06/14] perf tools: show NMI overhead Jiri Olsa <jolsa@redhat.com> - 2016-11-24 16:30 +0100
Re: [PATCH 06/14] perf tools: show NMI overhead Namhyung Kim <namhyung@kernel.org> - 2016-11-25 00:30 +0100
Re: [PATCH 06/14] perf tools: show NMI overhead Jiri Olsa <jolsa@redhat.com> - 2016-11-25 00:50 +0100
Re: [PATCH 06/14] perf tools: show NMI overhead Andi Kleen <andi@firstfloor.org> - 2016-11-25 01:30 +0100
Re: [PATCH 06/14] perf tools: show NMI overhead Jiri Olsa <jolsa@redhat.com> - 2016-11-24 00:00 +0100
Re: [PATCH 00/14] export perf overheads information Ingo Molnar <mingo@kernel.org> - 2016-11-24 05:30 +0100
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