From 4738fa16907a933d72bbcae1b8922dc9330fde92 Mon Sep 17 00:00:00 2001 From: Lars Ellenberg Date: Mon, 21 Feb 2011 13:20:55 +0100 Subject: [PATCH] drbd: use clear_bit_unlock() where appropriate Some open-coded clear_bit(); smp_mb__after_clear_bit(); should in fact have been smp_mb__before_clear_bit(); clear_bit(); Instead, use clear_bit_unlock() to annotate the intention, and have it do the right thing. Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg --- drivers/block/drbd/drbd_bitmap.c | 3 +-- drivers/block/drbd/drbd_main.c | 3 +-- include/linux/lru_cache.h | 3 +-- lib/lru_cache.c | 10 ++++------ 4 files changed, 7 insertions(+), 12 deletions(-) diff --git a/drivers/block/drbd/drbd_bitmap.c b/drivers/block/drbd/drbd_bitmap.c index e8d652f197c3..4be737055718 100644 --- a/drivers/block/drbd/drbd_bitmap.c +++ b/drivers/block/drbd/drbd_bitmap.c @@ -219,8 +219,7 @@ static void bm_page_unlock_io(struct drbd_conf *mdev, int page_nr) { struct drbd_bitmap *b = mdev->bitmap; void *addr = &page_private(b->bm_pages[page_nr]); - clear_bit(BM_PAGE_IO_LOCK, addr); - smp_mb__after_clear_bit(); + clear_bit_unlock(BM_PAGE_IO_LOCK, addr); wake_up(&mdev->bitmap->bm_io_wait); } diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 592f0c949fd0..c77e51a40926 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -2818,8 +2818,7 @@ static int w_bitmap_io(struct drbd_work *w, int unused) put_ldev(mdev); } - clear_bit(BITMAP_IO, &mdev->flags); - smp_mb__after_clear_bit(); + clear_bit_unlock(BITMAP_IO, &mdev->flags); wake_up(&mdev->misc_wait); if (work->done) diff --git a/include/linux/lru_cache.h b/include/linux/lru_cache.h index 7a71ffad037c..4cceafb0732d 100644 --- a/include/linux/lru_cache.h +++ b/include/linux/lru_cache.h @@ -275,8 +275,7 @@ static inline int lc_try_lock(struct lru_cache *lc) */ static inline void lc_unlock(struct lru_cache *lc) { - clear_bit(__LC_DIRTY, &lc->flags); - smp_mb__after_clear_bit(); + clear_bit_unlock(__LC_DIRTY, &lc->flags); } static inline int lc_is_used(struct lru_cache *lc, unsigned int enr) diff --git a/lib/lru_cache.c b/lib/lru_cache.c index a07e7268d7ed..9f353f7f41ca 100644 --- a/lib/lru_cache.c +++ b/lib/lru_cache.c @@ -44,8 +44,8 @@ MODULE_LICENSE("GPL"); } while (0) #define RETURN(x...) do { \ - clear_bit(__LC_PARANOIA, &lc->flags); \ - smp_mb__after_clear_bit(); return x ; } while (0) + clear_bit_unlock(__LC_PARANOIA, &lc->flags); \ + return x ; } while (0) /* BUG() if e is not one of the elements tracked by lc */ #define PARANOIA_LC_ELEMENT(lc, e) do { \ @@ -438,8 +438,7 @@ void lc_changed(struct lru_cache *lc, struct lc_element *e) hlist_add_head(&e->colision, lc_hash_slot(lc, lc->new_number)); lc->changing_element = NULL; lc->new_number = LC_FREE; - clear_bit(__LC_DIRTY, &lc->flags); - smp_mb__after_clear_bit(); + clear_bit_unlock(__LC_DIRTY, &lc->flags); RETURN(); } @@ -463,8 +462,7 @@ unsigned int lc_put(struct lru_cache *lc, struct lc_element *e) /* move it to the front of LRU. */ list_move(&e->list, &lc->lru); lc->used--; - clear_bit(__LC_STARVING, &lc->flags); - smp_mb__after_clear_bit(); + clear_bit_unlock(__LC_STARVING, &lc->flags); } RETURN(e->refcnt); }