diff options
Diffstat (limited to 'tools/perf/util/evsel.c')
| -rw-r--r-- | tools/perf/util/evsel.c | 61 |
1 files changed, 53 insertions, 8 deletions
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index b2365a63db45..04e536ae4d88 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -990,6 +990,8 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts, * it overloads any global configuration. */ apply_config_terms(evsel, opts); + + evsel->ignore_missing_thread = opts->ignore_missing_thread; } static int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads) @@ -1419,6 +1421,33 @@ static int __open_attr__fprintf(FILE *fp, const char *name, const char *val, return fprintf(fp, " %-32s %s\n", name, val); } +static bool ignore_missing_thread(struct perf_evsel *evsel, + struct thread_map *threads, + int thread, int err) +{ + if (!evsel->ignore_missing_thread) + return false; + + /* The system wide setup does not work with threads. */ + if (evsel->system_wide) + return false; + + /* The -ESRCH is perf event syscall errno for pid's not found. */ + if (err != -ESRCH) + return false; + + /* If there's only one thread, let it fail. */ + if (threads->nr == 1) + return false; + + if (thread_map__remove(threads, thread)) + return false; + + pr_warning("WARNING: Ignored open failure for pid %d\n", + thread_map__pid(threads, thread)); + return true; +} + static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus, struct thread_map *threads) { @@ -1474,7 +1503,7 @@ retry_sample_id: for (cpu = 0; cpu < cpus->nr; cpu++) { for (thread = 0; thread < nthreads; thread++) { - int group_fd; + int fd, group_fd; if (!evsel->cgrp && !evsel->system_wide) pid = thread_map__pid(threads, thread); @@ -1484,21 +1513,37 @@ retry_open: pr_debug2("sys_perf_event_open: pid %d cpu %d group_fd %d flags %#lx", pid, cpus->map[cpu], group_fd, flags); - FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr, - pid, - cpus->map[cpu], - group_fd, flags); - if (FD(evsel, cpu, thread) < 0) { + fd = sys_perf_event_open(&evsel->attr, pid, cpus->map[cpu], + group_fd, flags); + + FD(evsel, cpu, thread) = fd; + + if (fd < 0) { err = -errno; + + if (ignore_missing_thread(evsel, threads, thread, err)) { + /* + * We just removed 1 thread, so take a step + * back on thread index and lower the upper + * nthreads limit. + */ + nthreads--; + thread--; + + /* ... and pretend like nothing have happened. */ + err = 0; + continue; + } + pr_debug2("\nsys_perf_event_open failed, error %d\n", err); goto try_fallback; } - pr_debug2(" = %d\n", FD(evsel, cpu, thread)); + pr_debug2(" = %d\n", fd); if (evsel->bpf_fd >= 0) { - int evt_fd = FD(evsel, cpu, thread); + int evt_fd = fd; int bpf_fd = evsel->bpf_fd; err = ioctl(evt_fd, |