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SubjectRe: [tip:perf/core] perf/x86/intel: Clean-up/reduce PEBS code
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tip-bot for Peter Zijlstra <tipbot@zytor.com> writes:
> +
> + at = (struct pebs_record_nhm *)(unsigned long)ds->pebs_buffer_base;
> + top = (struct pebs_record_nhm *)(unsigned long)ds->pebs_index;
>
> ds->pebs_index = ds->pebs_buffer_base;
>
> + n = (top - at) / x86_pmu.pebs_record_size;


This adds a full slow division to the PEBS hot path.

Does not seem like a improvement to me.

-Andi

--
ak@linux.intel.com -- Speaking for myself only


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