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| author | Jiri Olsa <jolsa@kernel.org> | 2017-01-09 10:51:59 +0100 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2017-01-11 16:48:02 -0300 |
| commit | 0c5824498e8bd5b7d30dc03448cd89efaee4bead (patch) | |
| tree | 67f7b3faa4cf8a38419e1e274aea33995451b02a | |
| parent | dc0c6127c231d4d264570497a916fa19740c915b (diff) | |
| download | linux-0c5824498e8bd5b7d30dc03448cd89efaee4bead.tar.gz linux-0c5824498e8bd5b7d30dc03448cd89efaee4bead.tar.bz2 linux-0c5824498e8bd5b7d30dc03448cd89efaee4bead.zip | |
perf record: Add switch-output size warning
Adding switch-output size warning if the requested
size of lower than the wakeup ring buffer size.
$ perf record --switch-output=1K ls
WARNING: switch-output data size lower than wakeup kernel buffer size (258K) expect bigger perf.data sizes
...
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1483955520-29063-6-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| -rw-r--r-- | tools/perf/builtin-record.c | 21 | ||||
| -rw-r--r-- | tools/perf/util/evlist.c | 2 | ||||
| -rw-r--r-- | tools/perf/util/evlist.h | 2 |
3 files changed, 24 insertions, 1 deletions
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 3fa64492ee62..93319e1be3ac 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -1377,6 +1377,23 @@ out_free: return ret; } +static void switch_output_size_warn(struct record *rec) +{ + u64 wakeup_size = perf_evlist__mmap_size(rec->opts.mmap_pages); + struct switch_output *s = &rec->switch_output; + + wakeup_size /= 2; + + if (s->size < wakeup_size) { + char buf[100]; + + unit_number__scnprintf(buf, sizeof(buf), wakeup_size); + pr_warning("WARNING: switch-output data size lower than " + "wakeup kernel buffer size (%s) " + "expect bigger perf.data sizes\n", buf); + } +} + static int switch_output_setup(struct record *rec) { struct switch_output *s = &rec->switch_output; @@ -1410,6 +1427,10 @@ static int switch_output_setup(struct record *rec) enabled: rec->timestamp_filename = true; s->enabled = true; + + if (s->size && !rec->opts.no_buffering) + switch_output_size_warn(rec); + return 0; } diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index dc4df3d2660e..b601f2814a30 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -1184,7 +1184,7 @@ unsigned long perf_event_mlock_kb_in_pages(void) return pages; } -static size_t perf_evlist__mmap_size(unsigned long pages) +size_t perf_evlist__mmap_size(unsigned long pages) { if (pages == UINT_MAX) pages = perf_event_mlock_kb_in_pages(); diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h index 4fd034f22d2f..389b9ccdf8c7 100644 --- a/tools/perf/util/evlist.h +++ b/tools/perf/util/evlist.h @@ -218,6 +218,8 @@ int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages, bool overwrite); void perf_evlist__munmap(struct perf_evlist *evlist); +size_t perf_evlist__mmap_size(unsigned long pages); + void perf_evlist__disable(struct perf_evlist *evlist); void perf_evlist__enable(struct perf_evlist *evlist); void perf_evlist__toggle_enable(struct perf_evlist *evlist); |