diff options
| author | Nick Piggin <npiggin@suse.de> | 2007-11-26 14:58:10 -0600 |
|---|---|---|
| committer | Dave Kleikamp <shaggy@linux.vnet.ibm.com> | 2008-01-03 13:11:44 -0600 |
| commit | 54af6233d1cb84cdfaa6ea44ea0db0bcf518baac (patch) | |
| tree | 031f07f853e18e2fe09b054a3a8e432424362e60 | |
| parent | 67e6682f18b3bf812a994ae027ff87174a297ae8 (diff) | |
| download | op-kernel-dev-54af6233d1cb84cdfaa6ea44ea0db0bcf518baac.zip op-kernel-dev-54af6233d1cb84cdfaa6ea44ea0db0bcf518baac.tar.gz | |
JFS is missing a memory barrier
JFS is missing a memory barrier needed to close the critical section before
clearing the lock bit. Use lock bitops for this.
unlock_page() has a second barrier after clearing the lock, which is
required because it checks whether the waitqueue is active without locks.
Such a barrier is not required here because the waitqueue spinlock is
always taken (something to think about if performance is an issue).
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
| -rw-r--r-- | fs/jfs/jfs_metapage.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/jfs/jfs_metapage.c b/fs/jfs/jfs_metapage.c index b27fa11..1dfaae5 100644 --- a/fs/jfs/jfs_metapage.c +++ b/fs/jfs/jfs_metapage.c @@ -39,11 +39,11 @@ static struct { #endif #define metapage_locked(mp) test_bit(META_locked, &(mp)->flag) -#define trylock_metapage(mp) test_and_set_bit(META_locked, &(mp)->flag) +#define trylock_metapage(mp) test_and_set_bit_lock(META_locked, &(mp)->flag) static inline void unlock_metapage(struct metapage *mp) { - clear_bit(META_locked, &mp->flag); + clear_bit_unlock(META_locked, &mp->flag); wake_up(&mp->wait); } |
