linux-kernel - Re: [RFC PATCH 85/86] treewide: drivers: remove cond

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Message-ID: <ZU1qgv1QNiSJFEOZ@google.com>
Date:   Thu, 9 Nov 2023 15:25:54 -0800
From:   Dmitry Torokhov <dmitry.torokhov@...il.com>
To:     Ankur Arora <ankur.a.arora@...cle.com>
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Subject: Re: [RFC PATCH 85/86] treewide: drivers: remove cond_resched()

Hi Anhur,

On Tue, Nov 07, 2023 at 03:08:21PM -0800, Ankur Arora wrote:
> There are broadly three sets of uses of cond_resched():
> 
> 1.  Calls to cond_resched() out of the goodness of our heart,
>     otherwise known as avoiding lockup splats.

...

What about RCU stalls? The calls to cond_resched() in evdev.c and
mousedev.c were added specifically to allow RCU to run in cases when
userspace passes a large buffer and the kernel is not fully preemptable.

Thanks.

-- 
Dmitry