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drbd: use clear_bit_unlock() where appropriate

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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 <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This commit is contained in:
Lars Ellenberg 2011-02-21 13:20:55 +01:00 committed by Philipp Reisner
parent 61610420f7
commit 4738fa1690
4 changed files with 7 additions and 12 deletions
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3
drivers/block/drbd/drbd_bitmap.c
View File

@ -219,8 +219,7 @@ static void bm_page_unlock_io(struct drbd_conf *mdev, int page_nr)
{ {
struct drbd_bitmap *b = mdev->bitmap; struct drbd_bitmap *b = mdev->bitmap;
void *addr = &page_private(b->bm_pages[page_nr]); void *addr = &page_private(b->bm_pages[page_nr]);
clear_bit(BM_PAGE_IO_LOCK, addr); clear_bit_unlock(BM_PAGE_IO_LOCK, addr);
smp_mb__after_clear_bit();
wake_up(&mdev->bitmap->bm_io_wait); wake_up(&mdev->bitmap->bm_io_wait);
} }

3
drivers/block/drbd/drbd_main.c
View File

@ -2818,8 +2818,7 @@ static int w_bitmap_io(struct drbd_work *w, int unused)
put_ldev(mdev); put_ldev(mdev);
} }
clear_bit(BITMAP_IO, &mdev->flags); clear_bit_unlock(BITMAP_IO, &mdev->flags);
smp_mb__after_clear_bit();
wake_up(&mdev->misc_wait); wake_up(&mdev->misc_wait);
if (work->done) if (work->done)

3
include/linux/lru_cache.h
View File

@ -275,8 +275,7 @@ static inline int lc_try_lock(struct lru_cache *lc)
*/ */
static inline void lc_unlock(struct lru_cache *lc) static inline void lc_unlock(struct lru_cache *lc)
{ {
clear_bit(__LC_DIRTY, &lc->flags); clear_bit_unlock(__LC_DIRTY, &lc->flags);
smp_mb__after_clear_bit();
} }
static inline int lc_is_used(struct lru_cache *lc, unsigned int enr) static inline int lc_is_used(struct lru_cache *lc, unsigned int enr)

10
lib/lru_cache.c
View File

@ -44,8 +44,8 @@ MODULE_LICENSE("GPL");
} while (0) } while (0)
#define RETURN(x...) do { \ #define RETURN(x...) do { \
clear_bit(__LC_PARANOIA, &lc->flags); \ clear_bit_unlock(__LC_PARANOIA, &lc->flags); \
smp_mb__after_clear_bit(); return x ; } while (0) return x ; } while (0)
/* BUG() if e is not one of the elements tracked by lc */ /* BUG() if e is not one of the elements tracked by lc */
#define PARANOIA_LC_ELEMENT(lc, e) do { \ #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)); hlist_add_head(&e->colision, lc_hash_slot(lc, lc->new_number));
lc->changing_element = NULL; lc->changing_element = NULL;
lc->new_number = LC_FREE; lc->new_number = LC_FREE;
clear_bit(__LC_DIRTY, &lc->flags); clear_bit_unlock(__LC_DIRTY, &lc->flags);
smp_mb__after_clear_bit();
RETURN(); RETURN();
} }
@ -463,8 +462,7 @@ unsigned int lc_put(struct lru_cache *lc, struct lc_element *e)
/* move it to the front of LRU. */ /* move it to the front of LRU. */
list_move(&e->list, &lc->lru); list_move(&e->list, &lc->lru);
lc->used--; lc->used--;
clear_bit(__LC_STARVING, &lc->flags); clear_bit_unlock(__LC_STARVING, &lc->flags);
smp_mb__after_clear_bit();
} }
RETURN(e->refcnt); RETURN(e->refcnt);
} }