perf sched: Fix memory leaks in 'perf sched map'

It maintains per-cpu pointers for the current thread but it doesn't
release the refcounts.

Fixes: 5e895278697c014e ("perf sched: Move curr_thread initialization to perf_sched__map()")
Reviewed-by: Ian Rogers <irogers@google.com>
Tested-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250703014942.1369397-4-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index fa4052e040201105ed6bda8b76dfcfec12489aee..b73989fb6acef8d6d5bdfc88ec879693ec37897e 100644 (file)
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -1634,6 +1634,7 @@ static int map_switch_event(struct perf_sched *sched, struct evsel *evsel,
        const char *color = PERF_COLOR_NORMAL;
        char stimestamp[32];
        const char *str;
+       int ret = -1;
 
        BUG_ON(this_cpu.cpu >= MAX_CPUS || this_cpu.cpu < 0);
 
@@ -1664,17 +1665,20 @@ static int map_switch_event(struct perf_sched *sched, struct evsel *evsel,
        sched_in = map__findnew_thread(sched, machine, -1, next_pid);
        sched_out = map__findnew_thread(sched, machine, -1, prev_pid);
        if (sched_in == NULL || sched_out == NULL)
-               return -1;
+               goto out;
 
        tr = thread__get_runtime(sched_in);
-       if (tr == NULL) {
-               thread__put(sched_in);
-               return -1;
-       }
+       if (tr == NULL)
+               goto out;
+
+       thread__put(sched->curr_thread[this_cpu.cpu]);
+       thread__put(sched->curr_out_thread[this_cpu.cpu]);
 
        sched->curr_thread[this_cpu.cpu] = thread__get(sched_in);
        sched->curr_out_thread[this_cpu.cpu] = thread__get(sched_out);
 
+       ret = 0;
+
        str = thread__comm_str(sched_in);
        new_shortname = 0;
        if (!tr->shortname[0]) {
@@ -1769,12 +1773,10 @@ sched_out:
        color_fprintf(stdout, color, "\n");
 
 out:
-       if (sched->map.task_name)
-               thread__put(sched_out);
-
+       thread__put(sched_out);
        thread__put(sched_in);
 
-       return 0;
+       return ret;
 }
 
 static int process_sched_switch_event(const struct perf_tool *tool,
@@ -3556,10 +3558,10 @@ static int perf_sched__map(struct perf_sched *sched)
 
        sched->curr_out_thread = calloc(MAX_CPUS, sizeof(*(sched->curr_out_thread)));
        if (!sched->curr_out_thread)
-               return rc;
+               goto out_free_curr_thread;
 
        if (setup_cpus_switch_event(sched))
-               goto out_free_curr_thread;
+               goto out_free_curr_out_thread;
 
        if (setup_map_cpus(sched))
                goto out_free_cpus_switch_event;
@@ -3590,7 +3592,14 @@ out_put_map_cpus:
 out_free_cpus_switch_event:
        free_cpus_switch_event(sched);
 
+out_free_curr_out_thread:
+       for (int i = 0; i < MAX_CPUS; i++)
+               thread__put(sched->curr_out_thread[i]);
+       zfree(&sched->curr_out_thread);
+
 out_free_curr_thread:
+       for (int i = 0; i < MAX_CPUS; i++)
+               thread__put(sched->curr_thread[i]);
        zfree(&sched->curr_thread);
        return rc;
 }