Re: [PATCH] Revert "perf: Add a counter for number of user access events in context"

From: Rob Herring
Date: Tue Aug 06 2024 - 09:38:03 EST


On Mon, Aug 5, 2024 at 5:10 PM Song Liu <song@xxxxxxxxxx> wrote:
>
> This reverts commit 82ff0c022d19c2ad69a472692bb7ee01ac07a40b.
>
> perf_event->nr_user is not used any more. Remove it.

What are you talking about? It is used whenever
PERF_EVENT_FLAG_USER_READ_CNT is set on an event:

arch/x86/events/core.c: event->hw.flags |=
PERF_EVENT_FLAG_USER_READ_CNT;
arch/x86/events/core.c: if (!(event->hw.flags & PERF_EVENT_FLAG_USER_READ_CNT))
arch/x86/events/core.c: if (!(event->hw.flags & PERF_EVENT_FLAG_USER_READ_CNT))
arch/x86/events/core.c: if (!(hwc->flags & PERF_EVENT_FLAG_USER_READ_CNT))
arch/x86/events/core.c: !!(event->hw.flags &
PERF_EVENT_FLAG_USER_READ_CNT);
drivers/perf/arm_pmuv3.c: return event->hw.flags &
PERF_EVENT_FLAG_USER_READ_CNT;
drivers/perf/arm_pmuv3.c: event->hw.flags |=
PERF_EVENT_FLAG_USER_READ_CNT;
drivers/perf/riscv_pmu.c: !!(event->hw.flags &
PERF_EVENT_FLAG_USER_READ_CNT) &&
drivers/perf/riscv_pmu.c: if (!(event->hw.flags &
PERF_EVENT_FLAG_USER_READ_CNT))
drivers/perf/riscv_pmu_legacy.c: event->hw.flags |=
PERF_EVENT_FLAG_USER_READ_CNT;
drivers/perf/riscv_pmu_legacy.c: event->hw.flags &=
~PERF_EVENT_FLAG_USER_READ_CNT;
drivers/perf/riscv_pmu_sbi.c: (hwc->flags &
PERF_EVENT_FLAG_USER_READ_CNT))
drivers/perf/riscv_pmu_sbi.c: (hwc->flags &
PERF_EVENT_FLAG_USER_READ_CNT))
drivers/perf/riscv_pmu_sbi.c: event->hw.flags |=
PERF_EVENT_FLAG_USER_READ_CNT;
drivers/perf/riscv_pmu_sbi.c: event->hw.flags &=
~PERF_EVENT_FLAG_USER_READ_CNT;

Rob