[PATCH v3 0/5] perf: arm_spe: Add format option for discard mode

James Clark james.clark at linaro.org
Mon Jan 13 06:33:46 PST 2025



On 10/01/2025 4:22 pm, Will Deacon wrote:
> On Wed, 08 Jan 2025 14:28:55 +0000, James Clark wrote:
>> Discard mode (Armv8.6) is a way to enable SPE related PMU events without
>> the overhead of recording any data. Add a format option, tests and docs
>> for it.
>>
>> In theory we could make the driver drop calls to allocate the aux buffer
>> when discard mode is enabled. This would give a small memory saving,
>> but I think there is potential to interfere with any tools that don't
>> expect this so I left the aux allocation untouched. Even old tools that
>> don't know about discard mode will be able to use it because we publish
>> the format option. Not allocating the aux buffer will have to be added
>> to tools which I've done in Perf.
>>
>> [...]
> 
> Applied driver and docs patches to will (for-next/perf), thanks!
> 
> [1/5] perf: arm_spe: Add format option for discard mode
>        https://git.kernel.org/will/c/d28d95bc63cb
> [2/5] perf docs: arm_spe: Document new discard mode
>        https://git.kernel.org/will/c/ba113ecad81a
> 
> Cheers,

Thanks Will. Arnaldo and Namhyung, are you ok to take the Perf changes now?

Thanks
James




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