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From:   gouhao@uniontech.com
To:     willy@infradead.org
Cc:     brauner@kernel.org, gouhao@uniontech.com,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        viro@zeniv.linux.org.uk
Subject: Re: [PATCH] fs/buffer: adjust the order of might_sleep() in __getblk_gfp()
Date:   Fri, 24 Mar 2023 09:52:01 +0800
Message-Id: <20230324015201.12511-1-gouhao@uniontech.com>
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>On Thu, Mar 23, 2023 at 05:37:52PM +0800, gouhao@uniontech.com wrote:
>> From: Gou Hao <gouhao@uniontech.com>
>> 
>> If 'bh' is found in cache, just return directly.
>> might_sleep() is only required on slow paths.
>
>You're missing the point.  The caller can't know whether the slow or
>fast path will be taken.  So it must _never_ call this function if it
>cannot sleep.
I see. Thank you for your explanation! :)