2020-12-17 02:08:12

by Xiangyang Yu

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Subject: [PATCH] mm/filemap: Fix warning: no previous prototype

Fixed the warning when building with warnings enabled (W=1),
This function is only used in filemap.c, so mark this function
with 'static'.

mm/filemap.c:830:14: warning: no previous prototype for ‘__add_to_page_cache_locked’ [-Wmissing-prototypes]

Signed-off-by: Xiangyang Yu <[email protected]>
---
mm/filemap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/filemap.c b/mm/filemap.c
index c178022d7893..edaba5251bec 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -827,7 +827,7 @@ int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask)
}
EXPORT_SYMBOL_GPL(replace_page_cache_page);

-noinline int __add_to_page_cache_locked(struct page *page,
+static noinline int __add_to_page_cache_locked(struct page *page,
struct address_space *mapping,
pgoff_t offset, gfp_t gfp,
void **shadowp)
--
2.23.0


2020-12-17 02:26:04

by Matthew Wilcox

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Subject: Re: [PATCH] mm/filemap: Fix warning: no previous prototype

On Thu, Dec 17, 2020 at 10:03:11AM +0800, Xiangyang Yu wrote:
> Fixed the warning when building with warnings enabled (W=1),
> This function is only used in filemap.c, so mark this function
> with 'static'.

Good grief, no. Look at the git history before proposing a patch.

2020-12-18 04:13:47

by Souptick Joarder

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Subject: Re: [PATCH] mm/filemap: Fix warning: no previous prototype

On Thu, Dec 17, 2020 at 7:53 AM Matthew Wilcox <[email protected]> wrote:
>
> On Thu, Dec 17, 2020 at 10:03:11AM +0800, Xiangyang Yu wrote:
> > Fixed the warning when building with warnings enabled (W=1),
> > This function is only used in filemap.c, so mark this function
> > with 'static'.
>
> Good grief, no. Look at the git history before proposing a patch.

revert "mm/filemap: add static for function __add_to_page_cache_locked"
Revert commit 3351b16af494 ("mm/filemap: add static for function
__add_to_page_cache_locked") due to incompatibility with
ALLOW_ERROR_INJECTION which result in build errors.

>

2020-12-18 18:00:21

by Andrew Morton

[permalink] [raw]
Subject: Re: [PATCH] mm/filemap: Fix warning: no previous prototype

On Fri, 18 Dec 2020 09:39:30 +0530 Souptick Joarder <[email protected]> wrote:

> On Thu, Dec 17, 2020 at 7:53 AM Matthew Wilcox <[email protected]> wrote:
> >
> > On Thu, Dec 17, 2020 at 10:03:11AM +0800, Xiangyang Yu wrote:
> > > Fixed the warning when building with warnings enabled (W=1),
> > > This function is only used in filemap.c, so mark this function
> > > with 'static'.
> >
> > Good grief, no. Look at the git history before proposing a patch.
>
> revert "mm/filemap: add static for function __add_to_page_cache_locked"
> Revert commit 3351b16af494 ("mm/filemap: add static for function
> __add_to_page_cache_locked") due to incompatibility with
> ALLOW_ERROR_INJECTION which result in build errors.
>

How about we add a prototype for __add_to_page_cache_locked() to squash
the warning, along with a comment explaining what's going on?

2020-12-21 19:38:13

by Souptick Joarder

[permalink] [raw]
Subject: Re: [PATCH] mm/filemap: Fix warning: no previous prototype

On Fri, Dec 18, 2020 at 11:27 PM Andrew Morton
<[email protected]> wrote:
>
> On Fri, 18 Dec 2020 09:39:30 +0530 Souptick Joarder <[email protected]> wrote:
>
> > On Thu, Dec 17, 2020 at 7:53 AM Matthew Wilcox <[email protected]> wrote:
> > >
> > > On Thu, Dec 17, 2020 at 10:03:11AM +0800, Xiangyang Yu wrote:
> > > > Fixed the warning when building with warnings enabled (W=1),
> > > > This function is only used in filemap.c, so mark this function
> > > > with 'static'.
> > >
> > > Good grief, no. Look at the git history before proposing a patch.
> >
> > revert "mm/filemap: add static for function __add_to_page_cache_locked"
> > Revert commit 3351b16af494 ("mm/filemap: add static for function
> > __add_to_page_cache_locked") due to incompatibility with
> > ALLOW_ERROR_INJECTION which result in build errors.
> >
>
> How about we add a prototype for __add_to_page_cache_locked() to squash
> the warning, along with a comment explaining what's going on?
>
I think adding a prototype will silence some kernel test robot warning
and future efforts to make it static. I will post a patch.