Re: [PATCH] perf: Fix 0 count issue of cpu-clock

[Peter Zijlstra]

On Tue, Nov 18, 2025 at 12:03:09PM +0100, Peter Zijlstra wrote:
> On Wed, Nov 12, 2025 at 04:05:26PM +0800, Dapeng Mi wrote:
> 
> > diff --git a/kernel/events/core.c b/kernel/events/core.c
> > index f6a08c73f783..77d3af5959c1 100644
> > --- a/kernel/events/core.c
> > +++ b/kernel/events/core.c
> > @@ -11964,7 +11964,7 @@ 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, flags | PERF_EF_UPDATE);
> >  }
> >  
> >  static void cpu_clock_event_read(struct perf_event *event)
> > @@ -12043,7 +12043,7 @@ static int task_clock_event_add(struct perf_event *event, int flags)
> >  
> >  static void task_clock_event_del(struct perf_event *event, int flags)
> >  {
> > -	task_clock_event_stop(event, PERF_EF_UPDATE);
> > +	task_clock_event_stop(event, flags | PERF_EF_UPDATE);
> >  }
> 
> I think it can both just be: PERF_EF_UPDATE. The only pmu::del() caller
> hands in flags=0, but if there were to be flags added, we'd have to
> audit all del methods anyway.
> 
> Also, the few comments we do have already note that ->del() must do
> ->stop(EF_UPDATE).

Updated patch now sits in queue/perf/urgent.