diff --git a/drivers/md/md.c b/drivers/md/md.c index 5ec9fdd5e668..da6370835c47 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -382,10 +382,7 @@ static DEFINE_SPINLOCK(all_mddevs_lock); static bool is_md_suspended(struct mddev *mddev) { - if (mddev->suspended) - return true; - else - return false; + return percpu_ref_is_dying(&mddev->active_io); } /* Rather than calling directly into the personality make_request function, * IO requests come here first so that we can check if the device is @@ -412,12 +409,10 @@ static bool is_suspended(struct mddev *mddev, struct bio *bio) void md_handle_request(struct mddev *mddev, struct bio *bio) { check_suspended: - rcu_read_lock(); if (is_suspended(mddev, bio)) { DEFINE_WAIT(__wait); /* Bail out if REQ_NOWAIT is set for the bio */ if (bio->bi_opf & REQ_NOWAIT) { - rcu_read_unlock(); bio_wouldblock_error(bio); return; } @@ -426,23 +421,19 @@ check_suspended: TASK_UNINTERRUPTIBLE); if (!is_suspended(mddev, bio)) break; - rcu_read_unlock(); schedule(); - rcu_read_lock(); } finish_wait(&mddev->sb_wait, &__wait); } - atomic_inc(&mddev->active_io); - rcu_read_unlock(); + if (!percpu_ref_tryget_live(&mddev->active_io)) + goto check_suspended; if (!mddev->pers->make_request(mddev, bio)) { - atomic_dec(&mddev->active_io); - wake_up(&mddev->sb_wait); + percpu_ref_put(&mddev->active_io); goto check_suspended; } - if (atomic_dec_and_test(&mddev->active_io) && is_md_suspended(mddev)) - wake_up(&mddev->sb_wait); + percpu_ref_put(&mddev->active_io); } EXPORT_SYMBOL(md_handle_request); @@ -490,11 +481,10 @@ void mddev_suspend(struct mddev *mddev) lockdep_assert_held(&mddev->reconfig_mutex); if (mddev->suspended++) return; - synchronize_rcu(); wake_up(&mddev->sb_wait); set_bit(MD_ALLOW_SB_UPDATE, &mddev->flags); - smp_mb__after_atomic(); - wait_event(mddev->sb_wait, atomic_read(&mddev->active_io) == 0); + percpu_ref_kill(&mddev->active_io); + wait_event(mddev->sb_wait, percpu_ref_is_zero(&mddev->active_io)); mddev->pers->quiesce(mddev, 1); clear_bit_unlock(MD_ALLOW_SB_UPDATE, &mddev->flags); wait_event(mddev->sb_wait, !test_bit(MD_UPDATING_SB, &mddev->flags)); @@ -512,6 +502,7 @@ void mddev_resume(struct mddev *mddev) lockdep_assert_held(&mddev->reconfig_mutex); if (--mddev->suspended) return; + percpu_ref_resurrect(&mddev->active_io); wake_up(&mddev->sb_wait); mddev->pers->quiesce(mddev, 0); @@ -690,7 +681,6 @@ void mddev_init(struct mddev *mddev) timer_setup(&mddev->safemode_timer, md_safemode_timeout, 0); atomic_set(&mddev->active, 1); atomic_set(&mddev->openers, 0); - atomic_set(&mddev->active_io, 0); spin_lock_init(&mddev->lock); atomic_set(&mddev->flush_pending, 0); init_waitqueue_head(&mddev->sb_wait); @@ -5767,6 +5757,12 @@ static void md_safemode_timeout(struct timer_list *t) } static int start_dirty_degraded; +static void active_io_release(struct percpu_ref *ref) +{ + struct mddev *mddev = container_of(ref, struct mddev, active_io); + + wake_up(&mddev->sb_wait); +} int md_run(struct mddev *mddev) { @@ -5847,10 +5843,15 @@ int md_run(struct mddev *mddev) nowait = nowait && bdev_nowait(rdev->bdev); } + err = percpu_ref_init(&mddev->active_io, active_io_release, + PERCPU_REF_ALLOW_REINIT, GFP_KERNEL); + if (err) + return err; + if (!bioset_initialized(&mddev->bio_set)) { err = bioset_init(&mddev->bio_set, BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS); if (err) - return err; + goto exit_active_io; } if (!bioset_initialized(&mddev->sync_set)) { err = bioset_init(&mddev->sync_set, BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS); @@ -6038,6 +6039,8 @@ abort: bioset_exit(&mddev->sync_set); exit_bio_set: bioset_exit(&mddev->bio_set); +exit_active_io: + percpu_ref_exit(&mddev->active_io); return err; } EXPORT_SYMBOL_GPL(md_run); @@ -6262,6 +6265,7 @@ void md_stop(struct mddev *mddev) */ __md_stop_writes(mddev); __md_stop(mddev); + percpu_ref_exit(&mddev->active_io); bioset_exit(&mddev->bio_set); bioset_exit(&mddev->sync_set); } @@ -7835,6 +7839,7 @@ static void md_free_disk(struct gendisk *disk) struct mddev *mddev = disk->private_data; percpu_ref_exit(&mddev->writes_pending); + percpu_ref_exit(&mddev->active_io); bioset_exit(&mddev->bio_set); bioset_exit(&mddev->sync_set); diff --git a/drivers/md/md.h b/drivers/md/md.h index 554a9026669a..6335cb86e52e 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -315,7 +315,7 @@ struct mddev { unsigned long sb_flags; int suspended; - atomic_t active_io; + struct percpu_ref active_io; int ro; int sysfs_active; /* set when sysfs deletes * are happening, so run/