Thread (423 messages) 423 messages, 2 authors, 2021-07-19
STALE1775d REVIEWED: 2 (0M)

[PATCH 4.19 418/421] perf report: Fix --task and --stat with pipe input

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-07-19 16:36:09
Also in: lkml
Subsystem: performance events subsystem, the rest · Maintainers: Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Namhyung Kim, Linus Torvalds

From: Namhyung Kim <namhyung@kernel.org>

[ Upstream commit 892ba7f18621a02af4428c58d97451f64685dba4 ]

Current 'perf report' fails to process a pipe input when --task or
--stat options are used.  This is because they reset all the tool
callbacks and fails to find a matching event for a sample.

When pipe input is used, the event info is passed via ATTR records so it
needs to handle that operation.  Otherwise the following error occurs.
Note, -14 (= -EFAULT) comes from evlist__parse_sample():

  # perf record -a -o- sleep 1 | perf report -i- --stat
  Can't parse sample, err = -14
  0x271044 [0x38]: failed to process type: 9
  Error:
  failed to process sample
  #

Committer testing:

Before:

  $ perf record -o- sleep 1 | perf report -i- --stat
  Can't parse sample, err = -14
  [ perf record: Woken up 1 times to write data ]
  0x1350 [0x30]: failed to process type: 9
  Error:
  failed to process sample
  [ perf record: Captured and wrote 0.000 MB - ]
  $

After:

  $ perf record -o- sleep 1 | perf report -i- --stat
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.000 MB - ]

  Aggregated stats:
             TOTAL events:         41
              COMM events:          2  ( 4.9%)
              EXIT events:          1  ( 2.4%)
            SAMPLE events:          9  (22.0%)
             MMAP2 events:          4  ( 9.8%)
              ATTR events:          1  ( 2.4%)
    FINISHED_ROUND events:          1  ( 2.4%)
        THREAD_MAP events:          1  ( 2.4%)
           CPU_MAP events:          1  ( 2.4%)
      EVENT_UPDATE events:          1  ( 2.4%)
         TIME_CONV events:          1  ( 2.4%)
           FEATURE events:         19  (46.3%)
  cycles:uhH stats:
            SAMPLE events:          9
  $

Fixes: a4a4d0a7a2b20f78 ("perf report: Add --stats option to display quick data statistics")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <redacted>
Tested-by: Arnaldo Carvalho de Melo <redacted>
Cc: Andi Kleen <redacted>
Cc: Ian Rogers <irogers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210630043058.1131295-1-namhyung@kernel.org (local)
Signed-off-by: Arnaldo Carvalho de Melo <redacted>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/perf/builtin-report.c | 6 ++++++
 1 file changed, 6 insertions(+)
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 05eae94d09cb..dea7ed3fb0a4 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -634,9 +634,14 @@ static void report__output_resort(struct report *rep)
 	ui_progress__finish();
 }
 
+static int process_attr(struct perf_tool *tool __maybe_unused,
+			union perf_event *event,
+			struct evlist **pevlist);
+
 static void stats_setup(struct report *rep)
 {
 	memset(&rep->tool, 0, sizeof(rep->tool));
+	rep->tool.attr = process_attr;
 	rep->tool.no_warn = true;
 }
 
@@ -656,6 +661,7 @@ static void tasks_setup(struct report *rep)
 		rep->tool.mmap = perf_event__process_mmap;
 		rep->tool.mmap2 = perf_event__process_mmap2;
 	}
+	rep->tool.attr = process_attr;
 	rep->tool.comm = perf_event__process_comm;
 	rep->tool.exit = perf_event__process_exit;
 	rep->tool.fork = perf_event__process_fork;
-- 
2.30.2


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