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SubjectRe: [PATCH v2] scsi: target: Save a few cycles in transport_lookup_[cmd|tmr]_lun()
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Le 16/08/2022 à 08:06, Chaitanya Kulkarni a écrit :
> On 8/15/22 13:52, Christophe JAILLET wrote:
>> Use percpu_ref_tryget_live_rcu() instead of percpu_ref_tryget_live() to
>> save a few cycles when it is known that the rcu lock is already
>> taken/released.
>>
>> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
>> ---
> do you have a quantitative data that shows actual savings of cycles?
>
> -ck
>

Some numbers were given for io_uring by the one who introduced
percpu_ref_tryget_live_rcu().

See [1].

I don't have specific numbers for the patch against scsi.

CJ


[1]:
https://lore.kernel.org/linux-kernel/cover.1634822969.git.asml.silence@gmail.com/

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