diff options
| author | Arnaldo Carvalho de Melo <acme@redhat.com> | 2017-07-03 13:26:32 -0300 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2017-07-18 23:14:13 -0300 |
| commit | 4b4cd50319127b3b606b8aaf3426d8972df1666a (patch) | |
| tree | caee0ec547de3233ce3fa4a8158746e4f79e5641 /tools/perf/builtin-record.c | |
| parent | db918acb356b8770a0fafbe96743031a56b91af6 (diff) | |
| download | linux-4b4cd50319127b3b606b8aaf3426d8972df1666a.tar.bz2 | |
perf record: Do not ask for precise_ip with --no-samples
When the user doesn't specify an event with -e/--event, 'perf record'
will use as a default the "cycles" event with the highest level of
precision in perf_event_attr.precise_ip, but --no-samples, if present,
is incompatible with precise_ip != 0, so use the newly introduced
__perf_event__add_default(precise = false) to fix that:
Before:
# perf record -n usleep 1
Please consider tweaking /proc/sys/kernel/perf_event_max_sample_rate.
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (cycles:ppp).
/bin/dmesg may provide additional information.
No CONFIG_PERF_EVENTS=y kernel support configured?
#
After:
# perf record -n usleep 1
Please consider tweaking /proc/sys/kernel/perf_event_max_sample_rate.
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.018 MB perf.data ]
[root@jouet /]# perf evlist -v
cycles: size: 112, sample_type: IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1
[root@jouet /]#
Reported-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-q991fw6s6rhjvrd5ye4t7qom@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/builtin-record.c')
| -rw-r--r-- | tools/perf/builtin-record.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 17a14bcce34a..64eef9a567d9 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -1821,7 +1821,7 @@ int cmd_record(int argc, const char **argv) record.opts.tail_synthesize = true; if (rec->evlist->nr_entries == 0 && - perf_evlist__add_default(rec->evlist) < 0) { + __perf_evlist__add_default(rec->evlist, !record.opts.no_samples) < 0) { pr_err("Not enough memory for event selector list\n"); goto out; } |