+ mm-munlock-remove-fields-to-fix-htmldocs-warnings.patch added to -mm tree

+ mm-munlock-remove-fields-to-fix-htmldocs-warnings.patch added to -mm tree

[Andrew Morton]

The patch titled
     Subject: mm/munlock: remove fields to fix htmldocs warnings
has been added to the -mm tree.  Its filename is
     mm-munlock-remove-fields-to-fix-htmldocs-warnings.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-munlock-remove-fields-to-fix-htmldocs-warnings.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-munlock-remove-fields-to-fix-htmldocs-warnings.patch

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------------------------------------------------------
From: Hugh Dickins <hughd@google.com>
Subject: mm/munlock: remove fields to fix htmldocs warnings

Stephen reports that 'make htmldocs' currently issues two warnings:

include/linux/mm_types.h:275: warning: Function parameter or member
'__filler' not described in 'folio'
include/linux/mm_types.h:275: warning: Function parameter or member
'mlock_count' not described in 'folio'

Certainly __filler doesn't want documenting there, and all but one use of
mlock_count is through page->mlock_count at present: so I think it's best
just to remove them both from struct folio for now, and sort out the right
way to document folio->mlock_count once that is the one true way.

Link: https://lkml.kernel.org/r/d2c8f66d-be8e-7c91-b0c8-b2f7ffb08bec@google.com
Fixes: 07ca76067308 ("mm/munlock: maintain page->mlock_count while unevictable")
Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/mm_types.h |    8 +-------
 mm/swap.c                |    4 ++--
 2 files changed, 3 insertions(+), 9 deletions(-)

--- a/include/linux/mm_types.h~mm-munlock-remove-fields-to-fix-htmldocs-warnings
+++ a/include/linux/mm_types.h
@@ -253,13 +253,7 @@ struct folio {
 		struct {
 	/* public: */
 			unsigned long flags;
-			union {
-				struct list_head lru;
-				struct {
-					void *__filler;
-					unsigned int mlock_count;
-				};
-			};
+			struct list_head lru;
 			struct address_space *mapping;
 			pgoff_t index;
 			void *private;
--- a/mm/swap.c~mm-munlock-remove-fields-to-fix-htmldocs-warnings
+++ a/mm/swap.c
@@ -1026,13 +1026,13 @@ static void __pagevec_lru_add_fn(struct
 		folio_clear_active(folio);
 		folio_set_unevictable(folio);
 		/*
-		 * folio->mlock_count = !!folio_test_mlocked(folio)?
+		 * page->mlock_count = !!PageMlocked(page)?
 		 * But that leaves __mlock_page() in doubt whether another
 		 * actor has already counted the mlock or not.  Err on the
 		 * safe side, underestimate, let page reclaim fix it, rather
 		 * than leaving a page on the unevictable LRU indefinitely.
 		 */
-		folio->mlock_count = 0;
+		folio_page(folio, 0)->mlock_count = 0;
 		if (!was_unevictable)
 			__count_vm_events(UNEVICTABLE_PGCULLED, nr_pages);
 	}
_

Patches currently in -mm which might be from hughd@google.com are

mm-munlock-remove-fields-to-fix-htmldocs-warnings.patch

Re: + mm-munlock-remove-fields-to-fix-htmldocs-warnings.patch added to -mm tree

[Matthew Wilcox]

On Mon, Mar 28, 2022 at 01:09:36PM -0700, Andrew Morton wrote:
> 
> The patch titled
>      Subject: mm/munlock: remove fields to fix htmldocs warnings
> has been added to the -mm tree.  Its filename is
>      mm-munlock-remove-fields-to-fix-htmldocs-warnings.patch

Ugh, no, I'll fix the kernel-doc.