diff options
Diffstat (limited to 'fs/btrfs/locking.c')
| -rw-r--r-- | fs/btrfs/locking.c | 29 |
1 files changed, 11 insertions, 18 deletions
diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c index 74d8e2003f..6a0b7abb5b 100644 --- a/fs/btrfs/locking.c +++ b/fs/btrfs/locking.c @@ -13,7 +13,6 @@ #include "ctree.h" #include "extent_io.h" #include "locking.h" -#include "accessors.h" /* * Lockdep class keys for extent_buffer->lock's in this root. For a given @@ -85,7 +84,7 @@ void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb, int { struct btrfs_lockdep_keyset *ks; - BUG_ON(level >= ARRAY_SIZE(ks->keys)); + ASSERT(level < ARRAY_SIZE(ks->keys)); /* Find the matching keyset, id 0 is the default entry */ for (ks = btrfs_lockdep_keysets; ks->id; ks++) @@ -98,7 +97,7 @@ void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb, int void btrfs_maybe_reset_lockdep_class(struct btrfs_root *root, struct extent_buffer *eb) { if (test_bit(BTRFS_ROOT_RESET_LOCKDEP_CLASS, &root->state)) - btrfs_set_buffer_lockdep_class(root->root_key.objectid, + btrfs_set_buffer_lockdep_class(btrfs_root_id(root), eb, btrfs_header_level(eb)); } @@ -130,14 +129,14 @@ static void btrfs_set_eb_lock_owner(struct extent_buffer *eb, pid_t owner) { } */ /* - * __btrfs_tree_read_lock - lock extent buffer for read + * btrfs_tree_read_lock_nested - lock extent buffer for read * @eb: the eb to be locked * @nest: the nesting level to be used for lockdep * * This takes the read lock on the extent buffer, using the specified nesting * level for lockdep purposes. */ -void __btrfs_tree_read_lock(struct extent_buffer *eb, enum btrfs_lock_nesting nest) +void btrfs_tree_read_lock_nested(struct extent_buffer *eb, enum btrfs_lock_nesting nest) { u64 start_ns = 0; @@ -148,11 +147,6 @@ void __btrfs_tree_read_lock(struct extent_buffer *eb, enum btrfs_lock_nesting ne trace_btrfs_tree_read_lock(eb, start_ns); } -void btrfs_tree_read_lock(struct extent_buffer *eb) -{ - __btrfs_tree_read_lock(eb, BTRFS_NESTING_NORMAL); -} - /* * Try-lock for read. * @@ -199,7 +193,7 @@ void btrfs_tree_read_unlock(struct extent_buffer *eb) * * Returns with the eb->lock write locked. */ -void __btrfs_tree_lock(struct extent_buffer *eb, enum btrfs_lock_nesting nest) +void btrfs_tree_lock_nested(struct extent_buffer *eb, enum btrfs_lock_nesting nest) __acquires(&eb->lock) { u64 start_ns = 0; @@ -212,11 +206,6 @@ void __btrfs_tree_lock(struct extent_buffer *eb, enum btrfs_lock_nesting nest) trace_btrfs_tree_lock(eb, start_ns); } -void btrfs_tree_lock(struct extent_buffer *eb) -{ - __btrfs_tree_lock(eb, BTRFS_NESTING_NORMAL); -} - /* * Release the write lock. */ @@ -375,8 +364,12 @@ void btrfs_drew_write_lock(struct btrfs_drew_lock *lock) void btrfs_drew_write_unlock(struct btrfs_drew_lock *lock) { - atomic_dec(&lock->writers); - cond_wake_up(&lock->pending_readers); + /* + * atomic_dec_and_test() implies a full barrier, so woken up readers are + * guaranteed to see the decrement. + */ + if (atomic_dec_and_test(&lock->writers)) + wake_up(&lock->pending_readers); } void btrfs_drew_read_lock(struct btrfs_drew_lock *lock) |