From: Namhyung Kim Date: Wed, 30 Sep 2015 01:45:24 +0000 (+0900) Subject: perf record: Allocate area for sample_id_hdr in a synthesized comm event X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=e5bed564485b340d87f2d8945643a393e55b8225;p=deliverable%2Flinux.git perf record: Allocate area for sample_id_hdr in a synthesized comm event A previous patch added a synthesized comm event for forked child process but it missed that the event should contain area for sample_id_hdr at the end. It worked by accident since the perf_event union contains bigger event structs like mmap_events. This patch fixes it by dynamically allocating event struct including those area like in perf_event__synthesize_thread_map(). Reported-by: Arnaldo Carvalho de Melo Signed-off-by: Namhyung Kim Cc: David Ahern Cc: Jiri Olsa Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1443577526-3240-1-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index a01c8ae1ee07..5e01c070dbf2 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -637,17 +637,25 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) * Let the child rip */ if (forks) { - union perf_event event; + union perf_event *event; + + event = malloc(sizeof(event->comm) + machine->id_hdr_size); + if (event == NULL) { + err = -ENOMEM; + goto out_child; + } + /* * Some H/W events are generated before COMM event * which is emitted during exec(), so perf script * cannot see a correct process name for those events. * Synthesize COMM event to prevent it. */ - perf_event__synthesize_comm(tool, &event, + perf_event__synthesize_comm(tool, event, rec->evlist->workload.pid, process_synthesized_event, machine); + free(event); perf_evlist__start_workload(rec->evlist); }