linux-kernel - Re: [PATCH v2] drivers/staging/exfat: Replace binary semaphores for mutexes

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Message-ID: <74400.1572450057@turing-police>
Date:   Wed, 30 Oct 2019 11:40:57 -0400
From:   "Valdis Klētnieks" <valdis.kletnieks@...edu>
To:     Davidlohr Bueso <dave@...olabs.net>
cc:     gregkh@...uxfoundation.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2] drivers/staging/exfat: Replace binary semaphores for mutexes

On Wed, 30 Oct 2019 07:49:16 -0700, Davidlohr Bueso said:
> At a slight footprint cost (24 vs 32 bytes), mutexes are more optimal
> than semaphores; it's also a nicer interface for mutual exclusion,
> which is why they are encouraged over binary semaphores, when possible.
>
> For both v_sem and z_sem, their semantics imply traditional lock
> ownership; that is, the lock owner is the same for both lock/unlock
> operations. Therefore it is safe to convert.
>
> Signed-off-by: Davidlohr Bueso <dave@...olabs.net>

Looks sane.

Acked-by: Valdis Kletnieks <valdis.kletnieks@...edu>