diff options
author | Arnaldo Carvalho de Melo <acme@redhat.com> | 2014-12-11 18:04:10 -0300 |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2014-12-11 18:04:10 -0300 |
commit | e09b18d4907992d3d615b215c1abf585721b2810 (patch) | |
tree | b072fff64a3790e7862ae6f9a8681fffaa28c75d /tools | |
parent | 956fa57106d1ad3ffbe73f4534b9f3b3bc92dd6c (diff) | |
download | linux-stable-e09b18d4907992d3d615b215c1abf585721b2810.tar.gz linux-stable-e09b18d4907992d3d615b215c1abf585721b2810.tar.bz2 linux-stable-e09b18d4907992d3d615b215c1abf585721b2810.zip |
perf trace: Provide a better explanation when mmap fails
If we ask for a mmap lenght than the max configured via the relevant
sysctl, provide a better warning, instead of just expanding the EPERM
returned:
[acme@ssdandy ~]$ trace -m 256 -e nanosleep sleep 2
Error: Operation not permitted.
Hint: Check /proc/sys/kernel/perf_event_mlock_kb (516 kB) setting.
Hint: Tried using 1028 kB.
Hint: Try using a bigger -m/--mmap-pages value.
[acme@ssdandy ~]$ trace -m 128 -e nanosleep sleep 2
2001.280 (2000.403 ms): nanosleep(rqtp: 0x7fff89a8a7f0) = 0
[acme@ssdandy ~]$
An upcoming patch will autotune the request for non-root users when -m
is not used.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-cdvxfz2gycetbkopm9sna1qp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools')
-rw-r--r-- | tools/perf/builtin-trace.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 83a4835c8118..327541e43c7f 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -2045,7 +2045,6 @@ static int trace__run(struct trace *trace, int argc, const char **argv) unsigned long before; const bool forks = argc > 0; bool draining = false; - char sbuf[STRERR_BUFSIZE]; trace->live = true; @@ -2106,11 +2105,8 @@ static int trace__run(struct trace *trace, int argc, const char **argv) goto out_error_open; err = perf_evlist__mmap(evlist, trace->opts.mmap_pages, false); - if (err < 0) { - fprintf(trace->output, "Couldn't mmap the events: %s\n", - strerror_r(errno, sbuf, sizeof(sbuf))); - goto out_delete_evlist; - } + if (err < 0) + goto out_error_mmap; perf_evlist__enable(evlist); @@ -2210,6 +2206,10 @@ out_error_tp: perf_evlist__strerror_tp(evlist, errno, errbuf, sizeof(errbuf)); goto out_error; +out_error_mmap: + perf_evlist__strerror_mmap(evlist, errno, errbuf, sizeof(errbuf)); + goto out_error; + out_error_open: perf_evlist__strerror_open(evlist, errno, errbuf, sizeof(errbuf)); |