libperf: Add perf_evlist__reset_id_hash()

Add the perf_evlist__reset_id_hash() function as an internal function so that it can be called by perf to reset the hash table. This is necessary for 'perf stat' to run the workload multiple times. Signed-off-by: Namhyung Kim <[email protected]> Acked-by: Jiri Olsa <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Ian Rogers <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
c-sky · Mar 6, 2021 · e2a99c9 · e2a99c9
1 parent 034f7ee
commit e2a99c9
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Showing 2 changed files with 11 additions and 4 deletions.
diff --git a/tools/lib/perf/evlist.c b/tools/lib/perf/evlist.c
@@ -26,13 +26,10 @@
 
 void perf_evlist__init(struct perf_evlist *evlist)
 {
-	int i;
-
-	for (i = 0; i < PERF_EVLIST__HLIST_SIZE; ++i)
-		INIT_HLIST_HEAD(&evlist->heads[i]);
 	INIT_LIST_HEAD(&evlist->entries);
 	evlist->nr_entries = 0;
 	fdarray__init(&evlist->pollfd, 64);
+	perf_evlist__reset_id_hash(evlist);
 }
 
 static void __perf_evlist__propagate_maps(struct perf_evlist *evlist,
@@ -237,6 +234,14 @@ static void perf_evlist__id_hash(struct perf_evlist *evlist,
 	hlist_add_head(&sid->node, &evlist->heads[hash]);
 }
 
+void perf_evlist__reset_id_hash(struct perf_evlist *evlist)
+{
+	int i;
+
+	for (i = 0; i < PERF_EVLIST__HLIST_SIZE; ++i)
+		INIT_HLIST_HEAD(&evlist->heads[i]);
+}
+
 void perf_evlist__id_add(struct perf_evlist *evlist,
 			 struct perf_evsel *evsel,
 			 int cpu, int thread, u64 id)

diff --git a/tools/lib/perf/include/internal/evlist.h b/tools/lib/perf/include/internal/evlist.h
@@ -124,4 +124,6 @@ int perf_evlist__id_add_fd(struct perf_evlist *evlist,
 			   struct perf_evsel *evsel,
 			   int cpu, int thread, int fd);
 
+void perf_evlist__reset_id_hash(struct perf_evlist *evlist);
+
 #endif /* __LIBPERF_INTERNAL_EVLIST_H */