Commit-ID: 667d13da070a444aeb4ad4cf7b793c8c8f64dc5d Gitweb: http://git.kernel.org/tip/667d13da070a444aeb4ad4cf7b793c8c8f64dc5d Author: Ingo Molnar <mingo@xxxxxxx> AuthorDate: Mon, 15 Jun 2009 08:17:12 +0200 Committer: Ingo Molnar <mingo@xxxxxxx> CommitDate: Mon, 15 Jun 2009 08:17:12 +0200 perf record: Fix fast task-exit race Recording with -a (or with -p) can race with tasks going away: couldn't open /proc/8440/maps Causing an early exit() and no recording done. Do not abort the recording session - instead just skip that task. Also, only print the warnings under -v. Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Cc: Mike Galbraith <efault@xxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@xxxxxxx> --- tools/perf/builtin-record.c | 16 ++++++++++++---- tools/perf/builtin-report.c | 2 ++ 2 files changed, 14 insertions(+), 4 deletions(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index a177a59..e1dfef2 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -202,8 +202,12 @@ static void pid_synthesize_comm_event(pid_t pid, int full) fd = open(filename, O_RDONLY); if (fd < 0) { - fprintf(stderr, "couldn't open %s\n", filename); - exit(EXIT_FAILURE); + /* + * We raced with a task exiting - just return: + */ + if (verbose) + fprintf(stderr, "couldn't open %s\n", filename); + return; } if (read(fd, bf, sizeof(bf)) < 0) { fprintf(stderr, "couldn't read %s\n", filename); @@ -273,8 +277,12 @@ static void pid_synthesize_mmap_samples(pid_t pid) fp = fopen(filename, "r"); if (fp == NULL) { - fprintf(stderr, "couldn't open %s\n", filename); - exit(EXIT_FAILURE); + /* + * We raced with a task exiting - just return: + */ + if (verbose) + fprintf(stderr, "couldn't open %s\n", filename); + return; } while (1) { char bf[BUFSIZ], *pbf = bf; diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c index aebba56..51f38b2 100644 --- a/tools/perf/builtin-report.c +++ b/tools/perf/builtin-report.c @@ -983,6 +983,8 @@ process_overflow_event(event_t *event, unsigned long offset, unsigned long head) for (i = 0; i < chain->nr; i++) dprintf("..... %2d: %p\n", i, (void *)chain->ips[i]); } + if (chain->kernel) + ip = chain->ips[chain->kernel-1]; } dprintf(" ... thread: %s:%d\n", thread->comm, thread->pid); -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html