From 15ee9bc7ed171248d1405df5854da5fa91bfdc39 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Fri, 10 Aug 2007 16:22:09 -0400 Subject: [PATCH] Btrfs: delay commits during fsync to allow more writers Signed-off-by: Chris Mason --- fs/btrfs/btrfs_inode.h | 5 +++++ fs/btrfs/ctree.h | 1 + fs/btrfs/disk-io.c | 1 + fs/btrfs/file.c | 22 +++++++++++++++++---- fs/btrfs/inode.c | 2 ++ fs/btrfs/transaction.c | 44 ++++++++++++++++++++++++++++++------------ fs/btrfs/transaction.h | 7 +++++++ 7 files changed, 66 insertions(+), 16 deletions(-) diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index 6bce46be49ff..f446f161f736 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -25,6 +25,11 @@ struct btrfs_inode { struct btrfs_block_group_cache *block_group; struct btrfs_key location; struct inode vfs_inode; + + /* + * transid of the trans_handle that last modified this inode + */ + u64 last_trans; }; static inline struct btrfs_inode *BTRFS_I(struct inode *inode) { diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index d3cd564b3b3f..c7f5161271d3 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -301,6 +301,7 @@ struct btrfs_fs_info { struct radix_tree_root extent_map_radix; struct radix_tree_root extent_ins_radix; u64 generation; + u64 last_trans_committed; struct btrfs_transaction *running_transaction; struct btrfs_super_block *disk_super; struct btrfs_super_block super_copy; diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 192211274ce5..b2f79878d51a 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -435,6 +435,7 @@ struct btrfs_root *open_ctree(struct super_block *sb) INIT_LIST_HEAD(&fs_info->dead_roots); sb_set_blocksize(sb, 4096); fs_info->running_transaction = NULL; + fs_info->last_trans_committed = 0; fs_info->tree_root = tree_root; fs_info->extent_root = extent_root; fs_info->sb = sb; diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 00b118a2db69..6933ab11a5cd 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -694,22 +694,36 @@ static int btrfs_sync_file(struct file *file, { struct inode *inode = dentry->d_inode; struct btrfs_root *root = BTRFS_I(inode)->root; - int ret; + int ret = 0; struct btrfs_trans_handle *trans; /* - * FIXME, use inode generation number to check if we can skip the - * commit + * check the transaction that last modified this inode + * and see if its already been committed */ mutex_lock(&root->fs_info->fs_mutex); + if (!BTRFS_I(inode)->last_trans) + goto out; + mutex_lock(&root->fs_info->trans_mutex); + if (BTRFS_I(inode)->last_trans <= + root->fs_info->last_trans_committed) { + BTRFS_I(inode)->last_trans = 0; + mutex_unlock(&root->fs_info->trans_mutex); + goto out; + } + mutex_unlock(&root->fs_info->trans_mutex); + + /* + * ok we haven't committed the transaction yet, lets do a commit + */ trans = btrfs_start_transaction(root, 1); if (!trans) { ret = -ENOMEM; goto out; } ret = btrfs_commit_transaction(trans, root); - mutex_unlock(&root->fs_info->fs_mutex); out: + mutex_unlock(&root->fs_info->fs_mutex); return ret > 0 ? EIO : ret; } diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 5c05ecbc5726..398484179d82 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -193,6 +193,7 @@ static int btrfs_update_inode(struct btrfs_trans_handle *trans, fill_inode_item(inode_item, inode); btrfs_mark_buffer_dirty(path->nodes[0]); + btrfs_set_inode_last_trans(trans, inode); ret = 0; failed: btrfs_release_path(root, path); @@ -2234,6 +2235,7 @@ struct inode *btrfs_alloc_inode(struct super_block *sb) ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS); if (!ei) return NULL; + ei->last_trans = 0; return &ei->vfs_inode; } diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index c9d52dc83e48..18abea802794 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -55,7 +55,8 @@ static int join_transaction(struct btrfs_root *root) BUG_ON(!cur_trans); root->fs_info->generation++; root->fs_info->running_transaction = cur_trans; - cur_trans->num_writers = 0; + cur_trans->num_writers = 1; + cur_trans->num_joined = 0; cur_trans->transid = root->fs_info->generation; init_waitqueue_head(&cur_trans->writer_wait); init_waitqueue_head(&cur_trans->commit_wait); @@ -65,8 +66,11 @@ static int join_transaction(struct btrfs_root *root) cur_trans->start_time = get_seconds(); list_add_tail(&cur_trans->list, &root->fs_info->trans_list); init_bit_radix(&cur_trans->dirty_pages); + } else { + cur_trans->num_writers++; + cur_trans->num_joined++; } - cur_trans->num_writers++; + return 0; } @@ -428,12 +432,14 @@ static int drop_dirty_roots(struct btrfs_root *tree_root, int btrfs_commit_transaction(struct btrfs_trans_handle *trans, struct btrfs_root *root) { - int ret = 0; + unsigned long joined = 0; + unsigned long timeout = 1; struct btrfs_transaction *cur_trans; struct btrfs_transaction *prev_trans = NULL; struct list_head dirty_fs_roots; struct radix_tree_root pinned_copy; DEFINE_WAIT(wait); + int ret; init_bit_radix(&pinned_copy); INIT_LIST_HEAD(&dirty_fs_roots); @@ -448,7 +454,11 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, mutex_unlock(&root->fs_info->fs_mutex); ret = wait_for_commit(root, cur_trans); BUG_ON(ret); + + mutex_lock(&root->fs_info->trans_mutex); put_transaction(cur_trans); + mutex_unlock(&root->fs_info->trans_mutex); + mutex_lock(&root->fs_info->fs_mutex); return 0; } @@ -463,26 +473,35 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, mutex_unlock(&root->fs_info->trans_mutex); wait_for_commit(root, prev_trans); - put_transaction(prev_trans); mutex_lock(&root->fs_info->fs_mutex); mutex_lock(&root->fs_info->trans_mutex); + put_transaction(prev_trans); } } - while (trans->transaction->num_writers > 1) { + + do { + joined = cur_trans->num_joined; WARN_ON(cur_trans != trans->transaction); - prepare_to_wait(&trans->transaction->writer_wait, &wait, + prepare_to_wait(&cur_trans->writer_wait, &wait, TASK_UNINTERRUPTIBLE); - if (trans->transaction->num_writers <= 1) - break; + + if (cur_trans->num_writers > 1) + timeout = MAX_SCHEDULE_TIMEOUT; + else + timeout = 1; + mutex_unlock(&root->fs_info->fs_mutex); mutex_unlock(&root->fs_info->trans_mutex); - schedule(); + + schedule_timeout(timeout); + mutex_lock(&root->fs_info->fs_mutex); mutex_lock(&root->fs_info->trans_mutex); - finish_wait(&trans->transaction->writer_wait, &wait); - } - finish_wait(&trans->transaction->writer_wait, &wait); + finish_wait(&cur_trans->writer_wait, &wait); + } while (cur_trans->num_writers > 1 || + (cur_trans->num_joined != joined)); + WARN_ON(cur_trans != trans->transaction); ret = add_dirty_roots(trans, &root->fs_info->fs_roots_radix, &dirty_fs_roots); @@ -511,6 +530,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, btrfs_finish_extent_commit(trans, root, &pinned_copy); 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); put_transaction(cur_trans); put_transaction(cur_trans); diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h index d5f491d3757e..e451783a1a4d 100644 --- a/fs/btrfs/transaction.h +++ b/fs/btrfs/transaction.h @@ -23,6 +23,7 @@ struct btrfs_transaction { u64 transid; unsigned long num_writers; + unsigned long num_joined; int in_commit; int use_count; int commit_done; @@ -57,6 +58,12 @@ static inline void btrfs_update_inode_block_group(struct BTRFS_I(inode)->block_group = trans->block_group; } +static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans, + struct inode *inode) +{ + BTRFS_I(inode)->last_trans = trans->transaction->transid; +} + int btrfs_end_transaction(struct btrfs_trans_handle *trans, struct btrfs_root *root); struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, -- 2.25.1