linux/tools/perf/util/events_stats.h
Namhyung Kim 1a5474a779 perf tools: Print lost samples due to BPF filter
Print the actual dropped sample count in the event stat.

  $ sudo perf record -o- -e cycles --filter 'period < 10000' \
      -e instructions --filter 'ip > 0x8000000000000000' perf test -w noploop | \
      perf report --stat -i-
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.058 MB - ]

  Aggregated stats:
                 TOTAL events:        469
                  MMAP events:        268  (57.1%)
                  COMM events:          2  ( 0.4%)
                  EXIT events:          1  ( 0.2%)
                SAMPLE events:         16  ( 3.4%)
                 MMAP2 events:         22  ( 4.7%)
          LOST_SAMPLES events:          2  ( 0.4%)
               KSYMBOL events:         89  (19.0%)
             BPF_EVENT events:         39  ( 8.3%)
                  ATTR events:          2  ( 0.4%)
        FINISHED_ROUND events:          1  ( 0.2%)
              ID_INDEX events:          1  ( 0.2%)
            THREAD_MAP events:          1  ( 0.2%)
               CPU_MAP events:          1  ( 0.2%)
          EVENT_UPDATE events:          2  ( 0.4%)
             TIME_CONV events:          1  ( 0.2%)
               FEATURE events:         20  ( 4.3%)
         FINISHED_INIT events:          1  ( 0.2%)
  cycles stats:
                SAMPLE events:          2
    LOST_SAMPLES (BPF) events:       4010
  instructions stats:
                SAMPLE events:         14
    LOST_SAMPLES (BPF) events:       3990

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240820154504.128923-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-08-28 18:07:20 -03:00

71 lines
2.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __PERF_EVENTS_STATS_
#define __PERF_EVENTS_STATS_
#include <stdio.h>
#include <perf/event.h>
#include <linux/types.h>
#include "auxtrace.h"
/*
* The kernel collects the number of events it couldn't send in a stretch and
* when possible sends this number in a PERF_RECORD_LOST event. The number of
* such "chunks" of lost events is stored in .nr_events[PERF_EVENT_LOST] while
* total_lost tells exactly how many events the kernel in fact lost, i.e. it is
* the sum of all struct perf_record_lost.lost fields reported.
*
* The kernel discards mixed up samples and sends the number in a
* PERF_RECORD_LOST_SAMPLES event. The number of lost-samples events is stored
* in .nr_events[PERF_RECORD_LOST_SAMPLES] while total_lost_samples tells
* exactly how many samples the kernel in fact dropped, i.e. it is the sum of
* all struct perf_record_lost_samples.lost fields reported without setting the
* misc field in the header.
*
* The BPF program can discard samples according to the filter expressions given
* by the user. This number is kept in a BPF map and dumped at the end of perf
* record in a PERF_RECORD_LOST_SAMPLES event. To differentiate it from other
* lost samples, perf tools sets PERF_RECORD_MISC_LOST_SAMPLES_BPF flag in the
* header.misc field. The number of dropped-samples events is stored in
* .nr_events[PERF_RECORD_LOST_SAMPLES] while total_dropped_samples tells
* exactly how many samples the BPF program in fact dropped, i.e. it is the sum
* of all struct perf_record_lost_samples.lost fields reported with the misc
* field set in the header.
*
* The total_period is needed because by default auto-freq is used, so
* multiplying nr_events[PERF_EVENT_SAMPLE] by a frequency isn't possible to get
* the total number of low level events, it is necessary to sum all struct
* perf_record_sample.period and stash the result in total_period.
*/
struct events_stats {
u64 total_lost;
u64 total_lost_samples;
u64 total_dropped_samples;
u64 total_aux_lost;
u64 total_aux_partial;
u64 total_aux_collision;
u64 total_invalid_chains;
u32 nr_events[PERF_RECORD_HEADER_MAX];
u32 nr_lost_warned;
u32 nr_unknown_events;
u32 nr_invalid_chains;
u32 nr_unknown_id;
u32 nr_unprocessable_samples;
u32 nr_auxtrace_errors[PERF_AUXTRACE_ERROR_MAX];
u32 nr_proc_map_timeout;
};
struct hists_stats {
u64 total_period;
u64 total_non_filtered_period;
u32 nr_samples;
u32 nr_non_filtered_samples;
u32 nr_lost_samples;
u32 nr_dropped_samples;
};
void events_stats__inc(struct events_stats *stats, u32 type);
size_t events_stats__fprintf(struct events_stats *stats, FILE *fp);
#endif /* __PERF_EVENTS_STATS_ */