Re: [Patch v3 10/22] perf/x86/intel: Process arch-PEBS records or record fragments

Liang, Kan
2025-04-15T16:09:35Z

On 2025-04-15 9:57 a.m., Peter Zijlstra wrote:
> On Tue, Apr 15, 2025 at 11:44:16AM +0000, Dapeng Mi wrote:
>> A significant difference with adaptive PEBS is that arch-PEBS record
>> supports fragments which means an arch-PEBS record could be split into
>> several independent fragments which have its own arch-PEBS header in
>> each fragment.
>
> With the constraint that all fragments for a single event are
> contiguous, right?

Yes. If a record is split into n fragments, the first n-1 fragments will
have the CONTINUED bit set and the last fragment will have its CONTINUED
bit cleared. They are contiguous.

Thanks,
Kan