diff options
| author | Jonathan E Brassow <jbrassow@redhat.com> | 2005-11-21 21:32:37 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-11-22 09:14:31 -0800 |
| commit | 7692c5dd48026d952199c2b97c3418f927cc0407 (patch) | |
| tree | f198721b3b65a782ae0ed7400120cc45e0ce87c1 | |
| parent | 233886dd32ad71daf9c21bf3728c0933a94870f0 (diff) | |
[PATCH] device-mapper raid1: drop mark_region spinlock fix
The spinlock region_lock is held while calling mark_region which can sleep.
Drop the spinlock before calling that function.
A region's state and inclusion in the clean list are altered by rh_inc and
rh_dec. The state variable is set to RH_CLEAN in rh_dec, but only if
'pending' is zero. It is set to RH_DIRTY in rh_inc, but not if it is already
so. The changes to 'pending', the state, and the region's inclusion in the
clean list need to be atomicly.
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | drivers/md/dm-raid1.c | 20 |
1 files changed, 9 insertions, 11 deletions
diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c index 2375709a392..6b0fc167092 100644 --- a/drivers/md/dm-raid1.c +++ b/drivers/md/dm-raid1.c @@ -376,16 +376,18 @@ static void rh_inc(struct region_hash *rh, region_t region) read_lock(&rh->hash_lock); reg = __rh_find(rh, region); + spin_lock_irq(&rh->region_lock); atomic_inc(®->pending); - spin_lock_irq(&rh->region_lock); if (reg->state == RH_CLEAN) { - rh->log->type->mark_region(rh->log, reg->key); - reg->state = RH_DIRTY; list_del_init(®->list); /* take off the clean list */ - } - spin_unlock_irq(&rh->region_lock); + spin_unlock_irq(&rh->region_lock); + + rh->log->type->mark_region(rh->log, reg->key); + } else + spin_unlock_irq(&rh->region_lock); + read_unlock(&rh->hash_lock); } @@ -408,21 +410,17 @@ static void rh_dec(struct region_hash *rh, region_t region) reg = __rh_lookup(rh, region); read_unlock(&rh->hash_lock); + spin_lock_irqsave(&rh->region_lock, flags); if (atomic_dec_and_test(®->pending)) { - spin_lock_irqsave(&rh->region_lock, flags); - if (atomic_read(®->pending)) { /* check race */ - spin_unlock_irqrestore(&rh->region_lock, flags); - return; - } if (reg->state == RH_RECOVERING) { list_add_tail(®->list, &rh->quiesced_regions); } else { reg->state = RH_CLEAN; list_add(®->list, &rh->clean_regions); } - spin_unlock_irqrestore(&rh->region_lock, flags); should_wake = 1; } + spin_unlock_irqrestore(&rh->region_lock, flags); if (should_wake) wake(); |