Re: [Patch v3 3/7] perf/x86: Check if cpuc->events[*] pointer exists before accessing it

[Mi, Dapeng]

On 8/20/2025 1:44 PM, Andi Kleen wrote:
>> Andi, I didn't fully get the exact meaning about the "log" here. When
>> throttle is triggered, perf_event_throttle() has already called
>> perf_log_throttle() to log the throttle event although only for the group
>> leader. Is it enough?
> Throttle normally doesn't involve data loss, just less samples. But this
> is data loss, so it's an overflow.

IIUC, there should be no data loss, the unprocessed PEBS records of these
throttled events would be still processed eventually by calling
intel_pmu_drain_pebs_buffer() when stopping the event.


>
> -Andi
>