linux-kernel - Re: [PATCH] drbd: replace kmap() with kmap_local

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Message-Id: <176218298119.720460.5302997686043809131.b4-ty@kernel.dk>
Date: Mon, 03 Nov 2025 08:16:21 -0700
From: Jens Axboe <axboe@...nel.dk>
To: philipp.reisner@...bit.com, Shi Hao <i.shihao.999@...il.com>
Cc: lars.ellenberg@...bit.com, christoph.boehmwalder@...bit.com, 
 drbd-dev@...ts.linbit.com, linux-block@...r.kernel.org, 
 linux-kernel@...r.kernel.org
Subject: Re: [PATCH] drbd: replace kmap() with kmap_local_page() in
 receiver path


On Sat, 01 Nov 2025 11:14:22 +0530, Shi Hao wrote:
> Use kmap_local_page() instead of kmap() to avoid
> CPU contention.
> 
> kmap() uses a global set of mapping slots that can cause contention
> between multiple CPUs, while kmap_local_page() uses per-CPU slots
> eliminating this contention. It also ensures non-sleeping operation
> and provides better cache locality.
> 
> [...]

Applied, thanks!

[1/1] drbd: replace kmap() with kmap_local_page() in receiver path
      commit: 77220f6d18a22b0b5d73b5d2156609b0aa21a7c5

Best regards,
-- 
Jens Axboe