BACKPORT: mm: remove superfluous __ClearPageActive()
To activate a page, mark_page_accessed() always holds a reference on it. It either gets a new reference when adding a page to lru_pvecs.activate_page or reuses an existing one it previously got when it added a page to lru_pvecs.lru_add. So it doesn't call SetPageActive() on a page that doesn't have any reference left. Therefore, the race is impossible these days (I didn't brother to dig into its history). For other paths, namely reclaim and migration, a reference count is always held while calling SetPageActive() on a page. SetPageSlabPfmemalloc() also uses SetPageActive(), but it's irrelevant to LRU pages. Signed-off-by: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Yang Shi <shy828301@gmail.com> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Qian Cai <cai@lca.pw> Link: http://lkml.kernel.org/r/20200818184704.3625199-2-yuzhao@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> (cherry picked from commit 6f4dd8de4835563de9bae797ce1d7a13465a7a7d) Bug: 228114874 Change-Id: Ie432a8580024926fe9d0fa18eeb5a31b23593b21
This commit is contained in:
parent
973f438bda
commit
b4b8113614
@ -392,8 +392,6 @@ void __put_devmap_managed_page(struct page *page)
|
|||||||
* holds a reference on the page.
|
* holds a reference on the page.
|
||||||
*/
|
*/
|
||||||
if (count == 1) {
|
if (count == 1) {
|
||||||
/* Clear Active bit in case of parallel mark_page_accessed */
|
|
||||||
__ClearPageActive(page);
|
|
||||||
__ClearPageWaiters(page);
|
__ClearPageWaiters(page);
|
||||||
|
|
||||||
mem_cgroup_uncharge(page);
|
mem_cgroup_uncharge(page);
|
||||||
|
@ -830,8 +830,6 @@ void release_pages(struct page **pages, int nr)
|
|||||||
del_page_from_lru_list(page, lruvec, page_off_lru(page));
|
del_page_from_lru_list(page, lruvec, page_off_lru(page));
|
||||||
}
|
}
|
||||||
|
|
||||||
/* Clear Active bit in case of parallel mark_page_accessed */
|
|
||||||
__ClearPageActive(page);
|
|
||||||
__ClearPageWaiters(page);
|
__ClearPageWaiters(page);
|
||||||
|
|
||||||
list_add(&page->lru, &pages_to_free);
|
list_add(&page->lru, &pages_to_free);
|
||||||
|
Loading…
Reference in New Issue
Block a user