lkml.org 
[lkml]   [2013]   [Dec]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH -mm 4/7] mm: thp: turn put_compound_page() into __put_page_tail()
put_page(page) calls put_compound_page() if PageCompound(), but
put_compound_page() falls back to __put_nontail_page() if the page
is non-tail.

So we can simply shift the PageTail() logic from put_compound_page()
to put_page(), and put_page() can use __put_nontail_page() otherwise.

The patch also renames put_compound_page() to __put_page_tail() to
reflect the semantics change. And this way put_page() looks more
symmetrical with get_page().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---
mm/swap.c | 17 ++++++-----------
1 files changed, 6 insertions(+), 11 deletions(-)

diff --git a/mm/swap.c b/mm/swap.c
index b0e65b6..0400f3b 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -93,15 +93,10 @@ static void __put_nontail_page(struct page *page)
}
}

-static void put_compound_page(struct page *page)
+static void __put_page_tail(struct page *page)
{
struct page *page_head;

- if (likely(!PageTail(page))) {
- __put_nontail_page(page);
- return;
- }
-
/* __split_huge_page_refcount can run under us */
page_head = compound_trans_head(page);

@@ -222,10 +217,10 @@ out_put_single:

void put_page(struct page *page)
{
- if (unlikely(PageCompound(page)))
- put_compound_page(page);
- else if (put_page_testzero(page))
- __put_single_page(page);
+ if (unlikely(PageTail(page)))
+ __put_page_tail(page);
+ else
+ __put_nontail_page(page);
}
EXPORT_SYMBOL(put_page);

@@ -247,7 +242,7 @@ bool __get_page_tail(struct page *page)
bool got;
struct page *page_head = compound_trans_head(page);

- /* Ref to put_compound_page() comment. */
+ /* Ref to __put_page_tail() comment. */
if (!__compound_tail_refcounted(page_head)) {
smp_rmb();
if (likely(PageTail(page))) {
--
1.5.5.1


\
 
 \ /
  Last update: 2013-12-18 22:41    [W:0.137 / U:1.212 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site