Commit-ID: e09b18d4907992d3d615b215c1abf585721b2810 Gitweb: http://git.kernel.org/tip/e09b18d4907992d3d615b215c1abf585721b2810 Author: Arnaldo Carvalho de Melo <[email protected]> AuthorDate: Thu, 11 Dec 2014 18:04:10 -0300 Committer: Arnaldo Carvalho de Melo <[email protected]> CommitDate: Thu, 11 Dec 2014 18:04:10 -0300
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 <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: David Ahern <[email protected]> Cc: Don Zickus <[email protected]> Cc: Frederic Weisbecker <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Link: http://lkml.kernel.org/n/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> --- tools/perf/builtin-trace.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 83a4835..327541e 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)); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
