linux-kernel - Re: [PATCH v5 20/36] locking/ww_mutex: Support Clang's context analysis

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Message-ID: <8143ab09-fd9b-4615-8afb-7ee10e073c51@acm.org>
Date: Fri, 9 Jan 2026 13:26:23 -0800
From: Bart Van Assche <bvanassche@....org>
To: Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>
Cc: Marco Elver <elver@...gle.com>, Peter Zijlstra <peterz@...radead.org>,
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Subject: Re: [PATCH v5 20/36] locking/ww_mutex: Support Clang's context
 analysis

(+Maarten)

On 1/9/26 2:06 PM, Marco Elver wrote:
> If there's 1 out of N ww_mutex users that missed ww_acquire_done()
> there's a good chance that 1 case is wrong.

$ git grep -w ww_acquire_done '**c'|wc -l
11
$ git grep -w ww_acquire_fini '**c'|wc -l
33

The above statistics show that there are more cases where
ww_acquire_done() is not called rather than cases where
ww_acquire_done() is called.

Maarten, since you introduced the ww_mutex code, do you perhaps prefer
that calling ww_acquire_done() is optional or rather that all users that
do not call ww_acquire_done() are modified such that they call
ww_acquire_done()? The full email conversation is available here:
https://lore.kernel.org/all/20251219154418.3592607-1-elver@google.com/

Thanks,

Bart.