Re: [patch 1/2] mm: page-writeback: inline account_page_dirtied() into single caller

Michal Hocko
2014-10-23T12:21:54Z

On Wed 22-10-14 14:29:27, Johannes Weiner wrote:
> A follow-up patch would have changed the call signature. To save the
> trouble, just fold it instead.
>
> Signed-off-by: Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>
> Cc: "3.17" <stable-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>

It seems that the function was added just for nilfs but that wasn't using
the symbol at the time memcg part went in. Funny...

Acked-by: Michal Hocko <mhocko-AlSwsSmVLrQ@public.gmane.org>

> ---
> include/linux/mm.h | 1 -
> mm/page-writeback.c | 23 ++++-------------------
> 2 files changed, 4 insertions(+), 20 deletions(-)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 27eb1bfbe704..b46461116cd2 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -1235,7 +1235,6 @@ int __set_page_dirty_no_writeback(struct page *page);
> int redirty_page_for_writepage(struct writeback_control *wbc,
> struct page *page);
> void account_page_dirtied(struct page *page, struct address_space *mapping);
> -void account_page_writeback(struct page *page);
> int set_page_dirty(struct page *page);
> int set_page_dirty_lock(struct page *page);
> int clear_page_dirty_for_io(struct page *page);
> diff --git a/mm/page-writeback.c b/mm/page-writeback.c
> index ff24c9d83112..ff6a5b07211e 100644
> --- a/mm/page-writeback.c
> +++ b/mm/page-writeback.c
> @@ -2116,23 +2116,6 @@ void account_page_dirtied(struct page *page, struct address_space *mapping)
> EXPORT_SYMBOL(account_page_dirtied);
>
> /*
> - * Helper function for set_page_writeback family.
> - *
> - * The caller must hold mem_cgroup_begin/end_update_page_stat() lock
> - * while calling this function.
> - * See test_set_page_writeback for example.
> - *
> - * NOTE: Unlike account_page_dirtied this does not rely on being atomic
> - * wrt interrupts.
> - */
> -void account_page_writeback(struct page *page)
> -{
> - mem_cgroup_inc_page_stat(page, MEM_CGROUP_STAT_WRITEBACK);
> - inc_zone_page_state(page, NR_WRITEBACK);
> -}
> -EXPORT_SYMBOL(account_page_writeback);
> -
> -/*
> * For address_spaces which do not use buffers. Just tag the page as dirty in
> * its radix tree.
> *
> @@ -2410,8 +2393,10 @@ int __test_set_page_writeback(struct page *page, bool keep_write)
> } else {
> ret = TestSetPageWriteback(page);
> }
> - if (!ret)
> - account_page_writeback(page);
> + if (!ret) {
> + mem_cgroup_inc_page_stat(page, MEM_CGROUP_STAT_WRITEBACK);
> + inc_zone_page_state(page, NR_WRITEBACK);
> + }
> mem_cgroup_end_update_page_stat(page, &locked, &memcg_flags);
> return ret;
>
> --
> 2.1.2
>

--
Michal Hocko
SUSE Labs