Re: [PATCH v14 011/138] mm/lru: Add folio LRU functions

From: Mike Rapoport
Date: Wed Jul 21 2021 - 04:52:37 EST


On Wed, Jul 21, 2021 at 05:08:44AM +0100, Matthew Wilcox wrote:
> On Tue, Jul 20, 2021 at 01:44:10PM +0300, Mike Rapoport wrote:
> > It seems mm_inline.h is not a part of generated API docs, otherwise
> > kerneldoc would be unhappy about missing Return: description.
>
> It isn't, but I did add mm_inline.h to Documentation as part of this
> patch (thanks!) and made this change:
>
> /**
> - * folio_is_file_lru - should the folio be on a file LRU or anon LRU?
> - * @folio: the folio to test
> - *
> - * Returns 1 if @folio is a regular filesystem backed page cache folio
> - * or a lazily freed anonymous folio (e.g. via MADV_FREE). Returns 0 if
> - * @folio is a normal anonymous folio, a tmpfs folio or otherwise ram or
> - * swap backed folio. Used by functions that manipulate the LRU lists,
> - * to sort a folio onto the right LRU list.
> + * folio_is_file_lru - Should the folio be on a file LRU or anon LRU?
> + * @folio: The folio to test.
> *
> * We would like to get this info without a page flag, but the state
> * needs to survive until the folio is last deleted from the LRU, which
> * could be as far down as __page_cache_release.
> + *
> + * Return: An integer (not a boolean!) used to sort a folio onto the
> + * right LRU list and to account folios correctly.
> + * 1 if @folio is a regular filesystem backed page cache folio
> + * or a lazily freed anonymous folio (e.g. via MADV_FREE).
> + * 0 if @folio is a normal anonymous folio, a tmpfs folio or otherwise
> + * ram or swap backed folio.
> */
>
> I wanted to turn those last two sentences into a list, but my
> kernel-doc-fu abandoned me. Feel free to submit a follow-on patch to
> fix that ;-)

Here it is ;-)

Feel free to fold it into the original commit if you'd like to.