In funtion shrink_page_list(), page_mapped() is called several
times,save it to local val to reduce atomic_read.
Signed-off-by: Bob Liu <lliubbo@xxxxxxxxx>
---
mm/vmscan.c | 8 +++++---
1 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 79c8098..08cc3ac 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -637,6 +637,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
struct address_space *mapping;
struct page *page;
int may_enter_fs;
+ int page_mapcount;
cond_resched();
@@ -653,11 +654,12 @@ static unsigned long shrink_page_list(struct list_head *page_list,
if (unlikely(!page_evictable(page, NULL)))
goto cull_mlocked;
- if (!sc->may_unmap && page_mapped(page))
+ page_mapcount = page_mapped(page);
+ if (!sc->may_unmap && page_mapcount)
goto keep_locked;
/* Double the slab pressure for mapped and swapcache pages */
- if (page_mapped(page) || PageSwapCache(page))
+ if (page_mapcount || PageSwapCache(page))
sc->nr_scanned++;
may_enter_fs = (sc->gfp_mask & __GFP_FS) ||
@@ -707,7 +709,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
* The page is mapped into the page tables of one or more
* processes. Try to unmap it here.
*/
- if (page_mapped(page) && mapping) {
+ if (page_mapcount && mapping) {
switch (try_to_unmap(page, TTU_UNMAP)) {
case SWAP_FAIL:
goto activate_locked;
--
1.5.6.3
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxxx For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>