diff options
| author | Philipp Reisner <philipp.reisner@linbit.com> | 2010-11-17 18:24:19 +0100 |
|---|---|---|
| committer | Philipp Reisner <philipp.reisner@linbit.com> | 2011-03-10 11:35:01 +0100 |
| commit | 8869d683b7491467fd39fcbe79756fce3e6f35e7 (patch) | |
| tree | b8634a30967f36ff34f4de8ecf38eb96997f5f28 | |
| parent | 127b317844e7cc0458743b604998bece95eab030 (diff) | |
| download | linux-next-8869d683b7491467fd39fcbe79756fce3e6f35e7.tar.gz | |
drbd: Fixed inc_ap_bio()
The condition must be checked after perpare_to_wait(). The old
implementaion could loose wakeup events. Never observed in real
life.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
| -rw-r--r-- | drivers/block/drbd/drbd_int.h | 31 |
1 files changed, 14 insertions, 17 deletions
diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h index 77ac6765fd57..9a944604939f 100644 --- a/drivers/block/drbd/drbd_int.h +++ b/drivers/block/drbd/drbd_int.h @@ -2309,15 +2309,21 @@ static inline int __inc_ap_bio_cond(struct drbd_conf *mdev) return 1; } -/* I'd like to use wait_event_lock_irq, - * but I'm not sure when it got introduced, - * and not sure when it has 3 or 4 arguments */ -static inline void inc_ap_bio(struct drbd_conf *mdev, int count) +static inline int _inc_ap_bio_cond(struct drbd_conf *mdev, int count) { - /* compare with after_state_ch, - * os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S */ - DEFINE_WAIT(wait); + int rv = 0; + + spin_lock_irq(&mdev->req_lock); + rv = __inc_ap_bio_cond(mdev); + if (rv) + atomic_add(count, &mdev->ap_bio_cnt); + spin_unlock_irq(&mdev->req_lock); + + return rv; +} +static inline void inc_ap_bio(struct drbd_conf *mdev, int count) +{ /* we wait here * as long as the device is suspended * until the bitmap is no longer on the fly during connection @@ -2326,16 +2332,7 @@ static inline void inc_ap_bio(struct drbd_conf *mdev, int count) * to avoid races with the reconnect code, * we need to atomic_inc within the spinlock. */ - spin_lock_irq(&mdev->req_lock); - while (!__inc_ap_bio_cond(mdev)) { - prepare_to_wait(&mdev->misc_wait, &wait, TASK_UNINTERRUPTIBLE); - spin_unlock_irq(&mdev->req_lock); - schedule(); - finish_wait(&mdev->misc_wait, &wait); - spin_lock_irq(&mdev->req_lock); - } - atomic_add(count, &mdev->ap_bio_cnt); - spin_unlock_irq(&mdev->req_lock); + wait_event(mdev->misc_wait, _inc_ap_bio_cond(mdev, count)); } static inline void dec_ap_bio(struct drbd_conf *mdev) |