diff options
Diffstat (limited to 'fs/btrfs/transaction.c')
| -rw-r--r-- | fs/btrfs/transaction.c | 39 |
1 files changed, 24 insertions, 15 deletions
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 874e4394df86..0bf42dccb041 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -56,12 +56,17 @@ static struct kmem_cache *btrfs_trans_handle_cachep; * | Call btrfs_commit_transaction() on any trans handle attached to * | transaction N * V - * Transaction N [[TRANS_STATE_COMMIT_START]] + * Transaction N [[TRANS_STATE_COMMIT_PREP]] + * | + * | If there are simultaneous calls to btrfs_commit_transaction() one will win + * | the race and the rest will wait for the winner to commit the transaction. + * | + * | The winner will wait for previous running transaction to completely finish + * | if there is one. * | - * | Will wait for previous running transaction to completely finish if there - * | is one + * Transaction N [[TRANS_STATE_COMMIT_START]] * | - * | Then one of the following happes: + * | Then one of the following happens: * | - Wait for all other trans handle holders to release. * | The btrfs_commit_transaction() caller will do the commit work. * | - Wait for current transaction to be committed by others. @@ -112,6 +117,7 @@ static struct kmem_cache *btrfs_trans_handle_cachep; */ static const unsigned int btrfs_blocked_trans_types[TRANS_STATE_MAX] = { [TRANS_STATE_RUNNING] = 0U, + [TRANS_STATE_COMMIT_PREP] = 0U, [TRANS_STATE_COMMIT_START] = (__TRANS_START | __TRANS_ATTACH), [TRANS_STATE_COMMIT_DOING] = (__TRANS_START | __TRANS_ATTACH | @@ -1982,7 +1988,7 @@ void btrfs_commit_transaction_async(struct btrfs_trans_handle *trans) * Wait for the current transaction commit to start and block * subsequent transaction joins */ - btrfs_might_wait_for_state(fs_info, BTRFS_LOCKDEP_TRANS_COMMIT_START); + btrfs_might_wait_for_state(fs_info, BTRFS_LOCKDEP_TRANS_COMMIT_PREP); wait_event(fs_info->transaction_blocked_wait, cur_trans->state >= TRANS_STATE_COMMIT_START || TRANS_ABORTED(cur_trans)); @@ -2129,7 +2135,7 @@ static void add_pending_snapshot(struct btrfs_trans_handle *trans) return; lockdep_assert_held(&trans->fs_info->trans_lock); - ASSERT(cur_trans->state >= TRANS_STATE_COMMIT_START); + ASSERT(cur_trans->state >= TRANS_STATE_COMMIT_PREP); list_add(&trans->pending_snapshot->list, &cur_trans->pending_snapshots); } @@ -2153,7 +2159,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans) ktime_t interval; ASSERT(refcount_read(&trans->use_count) == 1); - btrfs_trans_state_lockdep_acquire(fs_info, BTRFS_LOCKDEP_TRANS_COMMIT_START); + btrfs_trans_state_lockdep_acquire(fs_info, BTRFS_LOCKDEP_TRANS_COMMIT_PREP); clear_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags); @@ -2213,7 +2219,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans) } spin_lock(&fs_info->trans_lock); - if (cur_trans->state >= TRANS_STATE_COMMIT_START) { + if (cur_trans->state >= TRANS_STATE_COMMIT_PREP) { enum btrfs_trans_state want_state = TRANS_STATE_COMPLETED; add_pending_snapshot(trans); @@ -2225,7 +2231,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans) want_state = TRANS_STATE_SUPER_COMMITTED; btrfs_trans_state_lockdep_release(fs_info, - BTRFS_LOCKDEP_TRANS_COMMIT_START); + BTRFS_LOCKDEP_TRANS_COMMIT_PREP); ret = btrfs_end_transaction(trans); wait_for_commit(cur_trans, want_state); @@ -2237,9 +2243,9 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans) return ret; } - cur_trans->state = TRANS_STATE_COMMIT_START; + cur_trans->state = TRANS_STATE_COMMIT_PREP; wake_up(&fs_info->transaction_blocked_wait); - btrfs_trans_state_lockdep_release(fs_info, BTRFS_LOCKDEP_TRANS_COMMIT_START); + btrfs_trans_state_lockdep_release(fs_info, BTRFS_LOCKDEP_TRANS_COMMIT_PREP); if (cur_trans->list.prev != &fs_info->trans_list) { enum btrfs_trans_state want_state = TRANS_STATE_COMPLETED; @@ -2260,11 +2266,9 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans) btrfs_put_transaction(prev_trans); if (ret) goto lockdep_release; - } else { - spin_unlock(&fs_info->trans_lock); + spin_lock(&fs_info->trans_lock); } } else { - spin_unlock(&fs_info->trans_lock); /* * The previous transaction was aborted and was already removed * from the list of transactions at fs_info->trans_list. So we @@ -2272,11 +2276,16 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans) * corrupt state (pointing to trees with unwritten nodes/leafs). */ if (BTRFS_FS_ERROR(fs_info)) { + spin_unlock(&fs_info->trans_lock); ret = -EROFS; goto lockdep_release; } } + cur_trans->state = TRANS_STATE_COMMIT_START; + wake_up(&fs_info->transaction_blocked_wait); + spin_unlock(&fs_info->trans_lock); + /* * Get the time spent on the work done by the commit thread and not * the time spent waiting on a previous commit @@ -2586,7 +2595,7 @@ lockdep_release: goto cleanup_transaction; lockdep_trans_commit_start_release: - btrfs_trans_state_lockdep_release(fs_info, BTRFS_LOCKDEP_TRANS_COMMIT_START); + btrfs_trans_state_lockdep_release(fs_info, BTRFS_LOCKDEP_TRANS_COMMIT_PREP); btrfs_end_transaction(trans); return ret; } |