diff options
| author |   Michael Petlan <mpetlan@redhat.com> | 2021-03-02 15:41:20 +0100 |
|---|---|---|
| committer |   Arnaldo Carvalho de Melo <acme@redhat.com> | 2021-03-06 16:54:32 -0300 |
| commit | 86a19008af5d88d5d523dbfe9b6ede11473e9a7f (patch) | |
| tree | 66faab23b448d9a37bc4b90d433d8076c13b8cb1 /tools/perf/builtin-trace.c | |
| parent | perf map: Tighten snprintf() string precision to pass gcc check on some 32-bit arches (diff) | |
| download | linux-dev-86a19008af5d88d5d523dbfe9b6ede11473e9a7f.tar.xz linux-dev-86a19008af5d88d5d523dbfe9b6ede11473e9a7f.zip | |
perf trace: Fix race in signal handling
Since a lot of stuff happens before the SIGINT signal handler is registered
(scanning /proc/*, etc.), on bigger systems, such as Cavium Sabre CN99xx,
it may happen that first interrupt signal is lost and perf isn't correctly
terminated.
The reproduction code might look like the following:
perf trace -a &
PERF_PID=$!
sleep 4
kill -INT $PERF_PID
The issue has been found on a CN99xx machine with RHEL-8 and the patch fixes
it by registering the signal handlers earlier in the init stage.
Suggested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Michael Petlan <mpetlan@redhat.com>
Tested-by: Michael Petlan <mpetlan@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/lkml/YEJnaMzH2ctp3PPx@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/builtin-trace.c')
| -rw-r--r-- | tools/perf/builtin-trace.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 85b6a46e85b6..7ec18ff57fc4 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -3964,9 +3964,6 @@ static int trace__run(struct trace *trace, int argc, const char **argv) evlist__config(evlist, &trace->opts, &callchain_param); - signal(SIGCHLD, sig_handler); - signal(SIGINT, sig_handler); - if (forks) { err = evlist__prepare_workload(evlist, &trace->opts.target, argv, false, NULL); if (err < 0) { @@ -4827,6 +4824,8 @@ int cmd_trace(int argc, const char **argv) signal(SIGSEGV, sighandler_dump_stack); signal(SIGFPE, sighandler_dump_stack); + signal(SIGCHLD, sig_handler); + signal(SIGINT, sig_handler); trace.evlist = evlist__new(); trace.sctbl = syscalltbl__new(); |