diff options
author | Chris Mason <chris.mason@oracle.com> | 2008-07-17 20:54:14 +0400 |
---|---|---|
committer | Chris Mason <chris.mason@oracle.com> | 2008-09-25 19:04:04 +0400 |
commit | f9295749388f82c8d2f485e99c72cd7c7876a99b (patch) | |
tree | 5089b0f723583d262116775b8b9fb5b4b8d291e0 /fs/btrfs/transaction.c | |
parent | dbe674a99c8af088faa4c95eddaeb271a3140ab6 (diff) | |
download | linux-f9295749388f82c8d2f485e99c72cd7c7876a99b.tar.xz |
btrfs_start_transaction: wait for commits in progress to finish
btrfs_commit_transaction has to loop waiting for any writers in the
transaction to finish before it can proceed. btrfs_start_transaction
should be polite and not join a transaction that is in the process
of being finished off.
There are a few places that can't wait, basically the ones doing IO that
might be needed to finish the transaction. For them, btrfs_join_transaction
is added.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs/transaction.c')
-rw-r--r-- | fs/btrfs/transaction.c | 43 |
1 files changed, 40 insertions, 3 deletions
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 86a5acc19ce7..05823904ecba 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -62,6 +62,7 @@ static noinline int join_transaction(struct btrfs_root *root) init_waitqueue_head(&cur_trans->writer_wait); init_waitqueue_head(&cur_trans->commit_wait); cur_trans->in_commit = 0; + cur_trans->blocked = 0; cur_trans->use_count = 1; cur_trans->commit_done = 0; cur_trans->start_time = get_seconds(); @@ -99,14 +100,36 @@ static noinline int record_root_in_trans(struct btrfs_root *root) return 0; } -struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, - int num_blocks) +struct btrfs_trans_handle *start_transaction(struct btrfs_root *root, + int num_blocks, int join) { struct btrfs_trans_handle *h = kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS); + struct btrfs_transaction *cur_trans; int ret; mutex_lock(&root->fs_info->trans_mutex); + cur_trans = root->fs_info->running_transaction; + if (cur_trans && cur_trans->blocked && !join) { + DEFINE_WAIT(wait); + cur_trans->use_count++; + while(1) { + prepare_to_wait(&root->fs_info->transaction_wait, &wait, + TASK_UNINTERRUPTIBLE); + if (cur_trans->blocked) { + mutex_unlock(&root->fs_info->trans_mutex); + schedule(); + mutex_lock(&root->fs_info->trans_mutex); + finish_wait(&root->fs_info->transaction_wait, + &wait); + } else { + finish_wait(&root->fs_info->transaction_wait, + &wait); + break; + } + } + put_transaction(cur_trans); + } ret = join_transaction(root); BUG_ON(ret); @@ -123,6 +146,17 @@ struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, return h; } +struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, + int num_blocks) +{ + return start_transaction(root, num_blocks, 0); +} +struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root, + int num_blocks) +{ + return start_transaction(root, num_blocks, 1); +} + static noinline int wait_for_commit(struct btrfs_root *root, struct btrfs_transaction *commit) { @@ -156,7 +190,7 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, if (waitqueue_active(&cur_trans->writer_wait)) wake_up(&cur_trans->writer_wait); - if (cur_trans->in_commit && throttle) { + if (0 && cur_trans->in_commit && throttle) { DEFINE_WAIT(wait); mutex_unlock(&root->fs_info->trans_mutex); prepare_to_wait(&root->fs_info->transaction_throttle, &wait, @@ -617,6 +651,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, printk("commit trans %Lu\n", trans->transid); trans->transaction->in_commit = 1; + trans->transaction->blocked = 1; cur_trans = trans->transaction; if (cur_trans->list.prev != &root->fs_info->trans_list) { prev_trans = list_entry(cur_trans->list.prev, @@ -684,7 +719,9 @@ printk("commit trans %Lu\n", trans->transid); btrfs_copy_pinned(root, pinned_copy); + trans->transaction->blocked = 0; wake_up(&root->fs_info->transaction_throttle); + wake_up(&root->fs_info->transaction_wait); mutex_unlock(&root->fs_info->trans_mutex); ret = btrfs_write_and_wait_transaction(trans, root); |