LinuxLists.cc - [PATCH] arm_pmu: Drop redundant armpmu->map_event() in armpmu_event

2022-11-30 08:46:52

Subject: [PATCH] arm_pmu: Drop redundant armpmu->map_event() in armpmu_event_init()

__hw_perf_event_init() already calls armpmu->map_event() callback, and also
returns its error code including -ENOENT, along with a debug callout. Hence
an additional armpmu->map_event() check for -ENOENT is redundant.

Cc: Catalin Marinas <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Anshuman Khandual <[email protected]>
---
This applies on v6.1-rc6

drivers/perf/arm_pmu.c | 4 ----
1 file changed, 4 deletions(-)

diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index 6538cec1a601..4be6869005f1 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c
@@ -529,10 +529,6 @@ static int armpmu_event_init(struct perf_event *event)
return -EOPNOTSUPP;
}
}
-
- if (armpmu->map_event(event) == -ENOENT)
- return -ENOENT;
-
return __hw_perf_event_init(event);
}

--
2.25.1

2022-12-01 12:42:41

by Mark Rutland

[permalink] [raw]

Subject: Re: [PATCH] arm_pmu: Drop redundant armpmu->map_event() in armpmu_event_init()

On Wed, Nov 30, 2022 at 02:03:50PM +0530, Anshuman Khandual wrote:
> __hw_perf_event_init() already calls armpmu->map_event() callback, and also
> returns its error code including -ENOENT, along with a debug callout. Hence
> an additional armpmu->map_event() check for -ENOENT is redundant.

Hmm; it looks like this has been redundant since commit:

e1f431b57ef9e4a6 ("ARM: perf: refactor event mapping")

... and was an oversight on my behalf.

This looks fine to me, so FWIW:

Acked-by: Mark Rutland <[email protected]>

Mark.

>
> Cc: Catalin Marinas <[email protected]>
> Cc: Will Deacon <[email protected]>
> Cc: Mark Rutland <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Anshuman Khandual <[email protected]>
> ---
> This applies on v6.1-rc6
>
> drivers/perf/arm_pmu.c | 4 ----
> 1 file changed, 4 deletions(-)
>
> diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
> index 6538cec1a601..4be6869005f1 100644
> --- a/drivers/perf/arm_pmu.c
> +++ b/drivers/perf/arm_pmu.c
> @@ -529,10 +529,6 @@ static int armpmu_event_init(struct perf_event *event)
> return -EOPNOTSUPP;
> }
> }
> -
> - if (armpmu->map_event(event) == -ENOENT)
> - return -ENOENT;
> -
> return __hw_perf_event_init(event);
> }
>
> --
> 2.25.1
>

2022-12-01 18:54:53

by Will Deacon

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