Re: [PATCH] fs/buffer: adjust the order of might_sleep() in __getblk_gfp()

[Matthew Wilcox]

On Thu, Mar 23, 2023 at 05:37:52PM +0800, gouhao@xxxxxxxxxxxxx wrote:
> From: Gou Hao <gouhao@xxxxxxxxxxxxx>
> 
> 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.