Re: [PATCH v2] ext4: fix prefetchw of NULL page

From: Theodore Ts'o
Date: Sun Apr 07 2019 - 12:06:59 EST


On Sun, Mar 31, 2019 at 04:11:34PM +0800, Liu Xiang wrote:
> In ext4_mpage_readpages(), if the parameter pages is not NULL, another
> parameter page is NULL. At the first time prefetchw(&page->flags)
> works on NULL. From second time, prefetchw(&page->flags) always works on
> the last consumed page. This might do little improvment for handling
> current page. So prefetchw() should be called while the page pointer
> has just been updated.

Thanks, applied.

- Ted