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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: i/cKeC1Yc5rbpk6NNa9ocxhNzQRfjgcoMhIzWdCEyWYE6jdkfm1uN/9/LmJjKiRfVRznD0tXVfEnS9kOR9637j7gEF0hveXfGQTm8JEkuhOJAPpQqwQSIXo0puPDRyOIIQIhmcBGxLbATPqthyfLKYtu/AgMgtpaQmeYTCtb0DHafhKy6zADO/eMenrVLfblGQVpyNNsuKg5R63EH9Ae1euJ6abgrwc/dj75zkV9m9qm3MTqhBAyCf8ZqJ1BOq4pOzzx2b9nJVn1DqaFBEVnTGqwfdh1UVP962uu/f0uuWnHIY+kg9zKfO9O3CidIlfViQpsA4q2BpntvANPrMr0kWH3GaIkr1Rywwazui1/77e1CqknAKnaFonB4uuwrUL7lOSrbg/jCsdvqGaEC9y0DGGHnpi1dsc6qE+gmiBwTUBDWh8Z9WdmoXqvjTo8UVN7 X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 May 2026 10:21:37.7629 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 13d413c6-d40a-46cc-6bac-08deb65993a1 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: SA2PEPF00003F62.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS2PR12MB9799 perf_sched__schedstat_live() has the same lost-wakeup race as perf_sched__schedstat_record(): a short-lived workload's SIGCHLD can be consumed by the signal handler before pause() is entered, hanging the process. Apply the same fix: replace pause() with a loop checking the 'done' flag and using waitpid(WNOHANG) for the workload case. Suggested-by: Namhyung Kim Assisted-by: Claude:claude-opus-4.6 Signed-off-by: Swapnil Sapkal --- tools/perf/builtin-sched.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c index 7da71c372e25..9e8941ae1b3d 100644 --- a/tools/perf/builtin-sched.c +++ b/tools/perf/builtin-sched.c @@ -4755,6 +4755,7 @@ static int perf_sched__schedstat_live(struct perf_sched *sched, int reset = 0; int err = 0; + done = 0; signal(SIGINT, sighandler); signal(SIGCHLD, sighandler); signal(SIGTERM, sighandler); @@ -4800,8 +4801,11 @@ static int perf_sched__schedstat_live(struct perf_sched *sched, if (argc) evlist__start_workload(evlist); - /* wait for signal */ - pause(); + while (!done) { + if (argc && waitpid(evlist->workload.pid, NULL, WNOHANG) > 0) + break; + sleep(1); + } if (reset) { err = disable_sched_schedstat(); -- 2.43.0