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perf: Fix 0 count issue of cpu-clock

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

authored by

Dapeng Mi and committed by
Peter Zijlstra
f1f96511 a24074ca

+1 -1
+1 -1
kernel/events/core.c
··· 11901 11901 11902 11902 static void cpu_clock_event_del(struct perf_event *event, int flags) 11903 11903 { 11904 - cpu_clock_event_stop(event, flags); 11904 + cpu_clock_event_stop(event, PERF_EF_UPDATE); 11905 11905 } 11906 11906 11907 11907 static void cpu_clock_event_read(struct perf_event *event)