6.17-stable review patch. If anyone has any objections, please let me know.
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From: Dapeng Mi dapeng1.mi@linux.intel.com
[ Upstream commit f1f96511b1c4c33e53f05909dd267878e0643a9a ]
Currently cpu-clock event always returns 0 count, e.g.,
perf stat -e cpu-clock -- sleep 1
Performance counter stats for 'sleep 1': 0 cpu-clock # 0.000 CPUs utilized 1.002308394 seconds time elapsed
The root cause is the commit 'bc4394e5e79c ("perf: Fix the throttle error of some clock events")' adds PERF_EF_UPDATE flag check before calling cpu_clock_event_update() to update the count, however the PERF_EF_UPDATE flag is never set when the cpu-clock event is stopped in counting mode (pmu->dev() -> cpu_clock_event_del() -> cpu_clock_event_stop()). This leads to the cpu-clock event count is never updated.
To fix this issue, force to set PERF_EF_UPDATE flag for cpu-clock event just like what task-clock does.
Fixes: bc4394e5e79c ("perf: Fix the throttle error of some clock events") Signed-off-by: Dapeng Mi dapeng1.mi@linux.intel.com Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Reviewed-by: Ian Rogers irogers@google.com Acked-by: Namhyung Kim namhyung@kernel.org Link: https://patch.msgid.link/20251112080526.3971392-1-dapeng1.mi@linux.intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/events/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/events/core.c b/kernel/events/core.c index f13565d0eb699..970c4a5ab763b 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -11885,7 +11885,7 @@ static int cpu_clock_event_add(struct perf_event *event, int flags)
static void cpu_clock_event_del(struct perf_event *event, int flags) { - cpu_clock_event_stop(event, flags); + cpu_clock_event_stop(event, PERF_EF_UPDATE); }
static void cpu_clock_event_read(struct perf_event *event)