Presumably __ClearPageWaiters() was added to follow the previously removed __ClearPageActive() pattern. Only flags that are in PAGE_FLAGS_CHECK_AT_FREE needs to be properly cleared because otherwise we think there may be some kind of leak. PG_waiters is not one of those flags and leaving the clearing to PAGE_FLAGS_CHECK_AT_PREP is more appropriate. Signed-off-by: Yu Zhao <yuzhao@xxxxxxxxxx> --- include/linux/page-flags.h | 2 +- mm/filemap.c | 2 ++ mm/memremap.c | 2 -- mm/swap.c | 3 --- 4 files changed, 3 insertions(+), 6 deletions(-) diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 6be1aa559b1e..dba80a2bdfba 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -318,7 +318,7 @@ static inline int TestClearPage##uname(struct page *page) { return 0; } TESTSETFLAG_FALSE(uname) TESTCLEARFLAG_FALSE(uname) __PAGEFLAG(Locked, locked, PF_NO_TAIL) -PAGEFLAG(Waiters, waiters, PF_ONLY_HEAD) __CLEARPAGEFLAG(Waiters, waiters, PF_ONLY_HEAD) +PAGEFLAG(Waiters, waiters, PF_ONLY_HEAD) PAGEFLAG(Error, error, PF_NO_TAIL) TESTCLEARFLAG(Error, error, PF_NO_TAIL) PAGEFLAG(Referenced, referenced, PF_HEAD) TESTCLEARFLAG(Referenced, referenced, PF_HEAD) diff --git a/mm/filemap.c b/mm/filemap.c index 1aaea26556cc..75240c7ef73f 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1079,6 +1079,8 @@ static void wake_up_page_bit(struct page *page, int bit_nr) * other pages on it. * * That's okay, it's a rare case. The next waker will clear it. + * Otherwise the bit will be cleared by PAGE_FLAGS_CHECK_AT_PREP + * when the page is being freed. */ } spin_unlock_irqrestore(&q->lock, flags); diff --git a/mm/memremap.c b/mm/memremap.c index 3a06eb91cb59..a9d02ffaf9e3 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -451,8 +451,6 @@ void free_devmap_managed_page(struct page *page) return; } - __ClearPageWaiters(page); - mem_cgroup_uncharge(page); /* diff --git a/mm/swap.c b/mm/swap.c index 999a84dbe12c..40bf20a75278 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -90,7 +90,6 @@ static void __page_cache_release(struct page *page) del_page_from_lru_list(page, lruvec, page_off_lru(page)); spin_unlock_irqrestore(&pgdat->lru_lock, flags); } - __ClearPageWaiters(page); } static void __put_single_page(struct page *page) @@ -900,8 +899,6 @@ void release_pages(struct page **pages, int nr) del_page_from_lru_list(page, lruvec, page_off_lru(page)); } - __ClearPageWaiters(page); - list_add(&page->lru, &pages_to_free); } if (locked_pgdat) -- 2.28.0.220.ged08abb693-goog