diff options
| author | Jiri Olsa <jolsa@kernel.org> | 2017-07-26 14:02:04 +0200 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2017-07-26 14:20:28 -0300 |
| commit | de63403bfd14ae8d613f30c9a0d415581b4cb37e (patch) | |
| tree | 2c4f35b85bf526a276e13dc6e042400d55974d54 | |
| parent | ee438ec8f33c5af0d4a4ffb935c5b9272e8c2680 (diff) | |
perf tools: Add perf_evsel__read_size function
Currently we use the size of struct perf_counts_values to read the
event, which prevents us to put any new member to the struct.
Adding perf_evsel__read_size to return size of the buffer needed for
event read.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170726120206.9099-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| -rw-r--r-- | tools/perf/util/evsel.c | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 450b5fadf8cb..4dd0fcc06db9 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -1261,15 +1261,42 @@ void perf_counts_values__scale(struct perf_counts_values *count, *pscaled = scaled; } +static int perf_evsel__read_size(struct perf_evsel *evsel) +{ + u64 read_format = evsel->attr.read_format; + int entry = sizeof(u64); /* value */ + int size = 0; + int nr = 1; + + if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) + size += sizeof(u64); + + if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) + size += sizeof(u64); + + if (read_format & PERF_FORMAT_ID) + entry += sizeof(u64); + + if (read_format & PERF_FORMAT_GROUP) { + nr = evsel->nr_members; + size += sizeof(u64); + } + + size += entry * nr; + return size; +} + int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread, struct perf_counts_values *count) { + size_t size = perf_evsel__read_size(evsel); + memset(count, 0, sizeof(*count)); if (FD(evsel, cpu, thread) < 0) return -EINVAL; - if (readn(FD(evsel, cpu, thread), count, sizeof(*count)) <= 0) + if (readn(FD(evsel, cpu, thread), count->values, size) <= 0) return -errno; return 0; |