xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Merge branch 'fix/waitqueue-barriers' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.4

Browse Source
This commit is contained in:
Chris Mason
2015-10-12 16:24:40 -07:00
parent 62fb50ab7c ee86395458
commit 6db4a7335d
12 changed files with 62 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
fs/btrfs/transaction.c
View File

@@ -82,6 +82,12 @@ void btrfs_put_transaction(struct btrfs_transaction *transaction)
static void clear_btree_io_tree(struct extent_io_tree *tree)
{
spin_lock(&tree->lock);
/*
* Do a single barrier for the waitqueue_active check here, the state
* of the waitqueue should not change once clear_btree_io_tree is
* called.
*/
smp_mb();
while (!RB_EMPTY_ROOT(&tree->state)) {
struct rb_node *node;
struct extent_state *state;
@@ -856,6 +862,9 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
atomic_dec(&cur_trans->num_writers);
extwriter_counter_dec(cur_trans, trans->type);
/*
* Make sure counter is updated before we wake up waiters.
*/
smp_mb();
if (waitqueue_active(&cur_trans->writer_wait))
wake_up(&cur_trans->writer_wait);