3 files changed, 46 insertions, 0 deletions

diff --git a/tools/perf/perf.h b/tools/perf/perf.h
index 9a0236a..1c27d94 100644
--- a/tools/perf/perf.h
+++ b/tools/perf/perf.h
@@ -55,6 +55,7 @@ struct record_opts {
 	bool	     all_user;
 	bool	     tail_synthesize;
 	bool	     overwrite;
+	bool	     ignore_missing_thread;
 	unsigned int freq;
 	unsigned int mmap_pages;
 	unsigned int auxtrace_mmap_pages;
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index fd61ebd..04e536a 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)
 {
@@ -1491,6 +1520,21 @@ retry_open:
 
 			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;
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 6abb89c..06ef6f2 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -120,6 +120,7 @@ struct perf_evsel {
 	bool			tracking;
 	bool			per_pkg;
 	bool			precise_max;
+	bool			ignore_missing_thread;
 	/* parse modifier helper */
 	int			exclude_GH;
 	int			nr_members;