diff options
Diffstat (limited to 'fs/btrfs/transaction.c')
-rw-r--r-- | fs/btrfs/transaction.c | 62 |
1 files changed, 55 insertions, 7 deletions
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 903edab3659..01c9620bb00 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -192,6 +192,7 @@ static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root, h->alloc_exclude_nr = 0; h->alloc_exclude_start = 0; h->delayed_ref_updates = 0; + root->fs_info->running_transaction->use_count++; mutex_unlock(&root->fs_info->trans_mutex); return h; @@ -281,7 +282,6 @@ void btrfs_throttle(struct btrfs_root *root) if (!root->fs_info->open_ioctl_trans) wait_current_trans(root); mutex_unlock(&root->fs_info->trans_mutex); - throttle_on_drops(root); } @@ -298,6 +298,13 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, if (cur && trans->transaction->delayed_refs.num_heads_ready > 64) { trans->delayed_ref_updates = 0; + + /* + * do a full flush if the transaction is trying + * to close + */ + if (trans->transaction->delayed_refs.flushing) + cur = 0; btrfs_run_delayed_refs(trans, root, cur); } else { break; @@ -666,6 +673,31 @@ int btrfs_defrag_root(struct btrfs_root *root, int cacheonly) } /* + * when dropping snapshots, we generate a ton of delayed refs, and it makes + * sense not to join the transaction while it is trying to flush the current + * queue of delayed refs out. + * + * This is used by the drop snapshot code only + */ +static noinline int wait_transaction_pre_flush(struct btrfs_fs_info *info) +{ + DEFINE_WAIT(wait); + + mutex_lock(&info->trans_mutex); + while (info->running_transaction && + info->running_transaction->delayed_refs.flushing) { + prepare_to_wait(&info->transaction_wait, &wait, + TASK_UNINTERRUPTIBLE); + mutex_unlock(&info->trans_mutex); + schedule(); + mutex_lock(&info->trans_mutex); + finish_wait(&info->transaction_wait, &wait); + } + mutex_unlock(&info->trans_mutex); + return 0; +} + +/* * Given a list of roots that need to be deleted, call btrfs_drop_snapshot on * all of them */ @@ -692,7 +724,22 @@ static noinline int drop_dirty_roots(struct btrfs_root *tree_root, atomic_inc(&root->fs_info->throttles); while (1) { + /* + * we don't want to jump in and create a bunch of + * delayed refs if the transaction is starting to close + */ + wait_transaction_pre_flush(tree_root->fs_info); trans = btrfs_start_transaction(tree_root, 1); + + /* + * we've joined a transaction, make sure it isn't + * closing right now + */ + if (trans->transaction->delayed_refs.flushing) { + btrfs_end_transaction(trans, tree_root); + continue; + } + mutex_lock(&root->fs_info->drop_mutex); ret = btrfs_drop_snapshot(trans, dirty->root); if (ret != -EAGAIN) @@ -932,20 +979,20 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, ret = btrfs_run_delayed_refs(trans, root, 0); BUG_ON(ret); + cur_trans = trans->transaction; /* * set the flushing flag so procs in this transaction have to * start sending their work down. */ - trans->transaction->delayed_refs.flushing = 1; + cur_trans->delayed_refs.flushing = 1; ret = btrfs_run_delayed_refs(trans, root, 0); BUG_ON(ret); - INIT_LIST_HEAD(&dirty_fs_roots); mutex_lock(&root->fs_info->trans_mutex); - if (trans->transaction->in_commit) { - cur_trans = trans->transaction; - trans->transaction->use_count++; + INIT_LIST_HEAD(&dirty_fs_roots); + if (cur_trans->in_commit) { + cur_trans->use_count++; mutex_unlock(&root->fs_info->trans_mutex); btrfs_end_transaction(trans, root); @@ -968,7 +1015,6 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, 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, struct btrfs_transaction, list); @@ -1081,6 +1127,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, btrfs_copy_pinned(root, pinned_copy); trans->transaction->blocked = 0; + wake_up(&root->fs_info->transaction_throttle); wake_up(&root->fs_info->transaction_wait); @@ -1107,6 +1154,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, mutex_lock(&root->fs_info->trans_mutex); cur_trans->commit_done = 1; + root->fs_info->last_trans_committed = cur_trans->transid; wake_up(&cur_trans->commit_wait); |