diff options
Diffstat (limited to 'fs')
-rw-r--r-- | fs/btrfs/ctree.h | 1 | ||||
-rw-r--r-- | fs/btrfs/disk-io.c | 36 | ||||
-rw-r--r-- | fs/btrfs/transaction.c | 157 | ||||
-rw-r--r-- | fs/btrfs/transaction.h | 16 |
4 files changed, 116 insertions, 94 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 905f7c6..fd62aa8 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1496,7 +1496,6 @@ struct btrfs_fs_info { int closing; int log_root_recovering; int enospc_unlink; - int trans_no_join; u64 total_pinned; diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 885245f..b9eaa0f 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1747,7 +1747,7 @@ static int transaction_kthread(void *arg) } now = get_seconds(); - if (!cur->blocked && + if (cur->state < TRANS_STATE_BLOCKED && (now < cur->start_time || now - cur->start_time < 30)) { spin_unlock(&root->fs_info->trans_lock); delay = HZ * 5; @@ -2186,7 +2186,6 @@ int open_ctree(struct super_block *sb, fs_info->max_inline = 8192 * 1024; fs_info->metadata_ratio = 0; fs_info->defrag_inodes = RB_ROOT; - fs_info->trans_no_join = 0; fs_info->free_chunk_space = 0; fs_info->tree_mod_log = RB_ROOT; @@ -3958,19 +3957,14 @@ void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans, btrfs_block_rsv_release(root, &root->fs_info->trans_block_rsv, cur_trans->dirty_pages.dirty_bytes); - /* FIXME: cleanup wait for commit */ - cur_trans->in_commit = 1; - cur_trans->blocked = 1; + cur_trans->state = TRANS_STATE_COMMIT_START; wake_up(&root->fs_info->transaction_blocked_wait); btrfs_evict_pending_snapshots(cur_trans); - cur_trans->blocked = 0; + cur_trans->state = TRANS_STATE_UNBLOCKED; wake_up(&root->fs_info->transaction_wait); - cur_trans->commit_done = 1; - wake_up(&cur_trans->commit_wait); - btrfs_destroy_delayed_inodes(root); btrfs_assert_delayed_root_empty(root); @@ -3979,6 +3973,9 @@ void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans, btrfs_destroy_pinned_extent(root, root->fs_info->pinned_extents); + cur_trans->state =TRANS_STATE_COMPLETED; + wake_up(&cur_trans->commit_wait); + /* memset(cur_trans, 0, sizeof(*cur_trans)); kmem_cache_free(btrfs_transaction_cachep, cur_trans); @@ -4006,25 +4003,23 @@ static int btrfs_cleanup_transaction(struct btrfs_root *root) btrfs_destroy_delayed_refs(t, root); - /* FIXME: cleanup wait for commit */ - t->in_commit = 1; - t->blocked = 1; + /* + * FIXME: cleanup wait for commit + * We needn't acquire the lock here, because we are during + * the umount, there is no other task which will change it. + */ + t->state = TRANS_STATE_COMMIT_START; smp_mb(); if (waitqueue_active(&root->fs_info->transaction_blocked_wait)) wake_up(&root->fs_info->transaction_blocked_wait); btrfs_evict_pending_snapshots(t); - t->blocked = 0; + t->state = TRANS_STATE_UNBLOCKED; smp_mb(); if (waitqueue_active(&root->fs_info->transaction_wait)) wake_up(&root->fs_info->transaction_wait); - t->commit_done = 1; - smp_mb(); - if (waitqueue_active(&t->commit_wait)) - wake_up(&t->commit_wait); - btrfs_destroy_delayed_inodes(root); btrfs_assert_delayed_root_empty(root); @@ -4036,6 +4031,11 @@ static int btrfs_cleanup_transaction(struct btrfs_root *root) btrfs_destroy_pinned_extent(root, root->fs_info->pinned_extents); + t->state = TRANS_STATE_COMPLETED; + smp_mb(); + if (waitqueue_active(&t->commit_wait)) + wake_up(&t->commit_wait); + atomic_set(&t->use_count, 0); list_del_init(&t->list); memset(t, 0, sizeof(*t)); diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 5e75ff4..eec8686 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -34,6 +34,29 @@ #define BTRFS_ROOT_TRANS_TAG 0 +static unsigned int btrfs_blocked_trans_types[TRANS_STATE_MAX] = { + [TRANS_STATE_RUNNING] = 0U, + [TRANS_STATE_BLOCKED] = (__TRANS_USERSPACE | + __TRANS_START), + [TRANS_STATE_COMMIT_START] = (__TRANS_USERSPACE | + __TRANS_START | + __TRANS_ATTACH), + [TRANS_STATE_COMMIT_DOING] = (__TRANS_USERSPACE | + __TRANS_START | + __TRANS_ATTACH | + __TRANS_JOIN), + [TRANS_STATE_UNBLOCKED] = (__TRANS_USERSPACE | + __TRANS_START | + __TRANS_ATTACH | + __TRANS_JOIN | + __TRANS_JOIN_NOLOCK), + [TRANS_STATE_COMPLETED] = (__TRANS_USERSPACE | + __TRANS_START | + __TRANS_ATTACH | + __TRANS_JOIN | + __TRANS_JOIN_NOLOCK), +}; + static void put_transaction(struct btrfs_transaction *transaction) { WARN_ON(atomic_read(&transaction->use_count) == 0); @@ -50,13 +73,6 @@ static noinline void switch_commit_root(struct btrfs_root *root) root->commit_root = btrfs_root_node(root); } -static inline int can_join_transaction(struct btrfs_transaction *trans, - unsigned int type) -{ - return !(trans->in_commit && - (type & TRANS_EXTWRITERS)); -} - static inline void extwriter_counter_inc(struct btrfs_transaction *trans, unsigned int type) { @@ -98,26 +114,13 @@ loop: return -EROFS; } - if (fs_info->trans_no_join) { - /* - * If we are JOIN_NOLOCK we're already committing a current - * transaction, we just need a handle to deal with something - * when committing the transaction, such as inode cache and - * space cache. It is a special case. - */ - if (type != TRANS_JOIN_NOLOCK) { - spin_unlock(&fs_info->trans_lock); - return -EBUSY; - } - } - cur_trans = fs_info->running_transaction; if (cur_trans) { if (cur_trans->aborted) { spin_unlock(&fs_info->trans_lock); return cur_trans->aborted; } - if (!can_join_transaction(cur_trans, type)) { + if (btrfs_blocked_trans_types[cur_trans->state] & type) { spin_unlock(&fs_info->trans_lock); return -EBUSY; } @@ -136,6 +139,12 @@ loop: if (type == TRANS_ATTACH) return -ENOENT; + /* + * JOIN_NOLOCK only happens during the transaction commit, so + * it is impossible that ->running_transaction is NULL + */ + BUG_ON(type == TRANS_JOIN_NOLOCK); + cur_trans = kmem_cache_alloc(btrfs_transaction_cachep, GFP_NOFS); if (!cur_trans) return -ENOMEM; @@ -144,7 +153,7 @@ loop: if (fs_info->running_transaction) { /* * someone started a transaction after we unlocked. Make sure - * to redo the trans_no_join checks above + * to redo the checks above */ kmem_cache_free(btrfs_transaction_cachep, cur_trans); goto loop; @@ -158,14 +167,12 @@ loop: extwriter_counter_init(cur_trans, type); 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->state = TRANS_STATE_RUNNING; /* * One for this trans handle, one so it will live on until we * commit the transaction. */ atomic_set(&cur_trans->use_count, 2); - cur_trans->commit_done = 0; cur_trans->start_time = get_seconds(); cur_trans->delayed_refs.root = RB_ROOT; @@ -188,7 +195,6 @@ loop: "creating a fresh transaction\n"); atomic64_set(&fs_info->tree_mod_seq, 0); - spin_lock_init(&cur_trans->commit_lock); spin_lock_init(&cur_trans->delayed_refs.lock); atomic_set(&cur_trans->delayed_refs.procs_running_refs, 0); atomic_set(&cur_trans->delayed_refs.ref_seq, 0); @@ -293,6 +299,12 @@ int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans, return 0; } +static inline int is_transaction_blocked(struct btrfs_transaction *trans) +{ + return (trans->state >= TRANS_STATE_BLOCKED && + trans->state < TRANS_STATE_UNBLOCKED); +} + /* wait for commit against the current transaction to become unblocked * when this is done, it is safe to start a new transaction, but the current * transaction might not be fully on disk. @@ -303,12 +315,12 @@ static void wait_current_trans(struct btrfs_root *root) spin_lock(&root->fs_info->trans_lock); cur_trans = root->fs_info->running_transaction; - if (cur_trans && cur_trans->blocked) { + if (cur_trans && is_transaction_blocked(cur_trans)) { atomic_inc(&cur_trans->use_count); spin_unlock(&root->fs_info->trans_lock); wait_event(root->fs_info->transaction_wait, - !cur_trans->blocked); + cur_trans->state >= TRANS_STATE_UNBLOCKED); put_transaction(cur_trans); } else { spin_unlock(&root->fs_info->trans_lock); @@ -432,7 +444,8 @@ again: INIT_LIST_HEAD(&h->new_bgs); smp_mb(); - if (cur_trans->blocked && may_wait_transaction(root, type)) { + if (cur_trans->state >= TRANS_STATE_BLOCKED && + may_wait_transaction(root, type)) { btrfs_commit_transaction(h, root); goto again; } @@ -536,7 +549,7 @@ btrfs_attach_transaction_barrier(struct btrfs_root *root) static noinline void wait_for_commit(struct btrfs_root *root, struct btrfs_transaction *commit) { - wait_event(commit->commit_wait, commit->commit_done); + wait_event(commit->commit_wait, commit->state == TRANS_STATE_COMPLETED); } int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid) @@ -572,8 +585,8 @@ int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid) spin_lock(&root->fs_info->trans_lock); list_for_each_entry_reverse(t, &root->fs_info->trans_list, list) { - if (t->in_commit) { - if (t->commit_done) + if (t->state >= TRANS_STATE_COMMIT_START) { + if (t->state == TRANS_STATE_COMPLETED) break; cur_trans = t; atomic_inc(&cur_trans->use_count); @@ -614,7 +627,8 @@ int btrfs_should_end_transaction(struct btrfs_trans_handle *trans, int err; smp_mb(); - if (cur_trans->blocked || cur_trans->delayed_refs.flushing) + if (cur_trans->state >= TRANS_STATE_BLOCKED || + cur_trans->delayed_refs.flushing) return 1; updates = trans->delayed_ref_updates; @@ -682,12 +696,15 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, btrfs_create_pending_block_groups(trans, root); if (lock && !atomic_read(&root->fs_info->open_ioctl_trans) && - should_end_transaction(trans, root)) { - trans->transaction->blocked = 1; - smp_wmb(); + should_end_transaction(trans, root) && + ACCESS_ONCE(cur_trans->state) == TRANS_STATE_RUNNING) { + spin_lock(&info->trans_lock); + if (cur_trans->state == TRANS_STATE_RUNNING) + cur_trans->state = TRANS_STATE_BLOCKED; + spin_unlock(&info->trans_lock); } - if (lock && cur_trans->blocked && !cur_trans->in_commit) { + if (lock && ACCESS_ONCE(cur_trans->state) == TRANS_STATE_BLOCKED) { if (throttle) { /* * We may race with somebody else here so end up having @@ -1343,20 +1360,26 @@ static void update_super_roots(struct btrfs_root *root) int btrfs_transaction_in_commit(struct btrfs_fs_info *info) { + struct btrfs_transaction *trans; int ret = 0; + spin_lock(&info->trans_lock); - if (info->running_transaction) - ret = info->running_transaction->in_commit; + trans = info->running_transaction; + if (trans) + ret = (trans->state >= TRANS_STATE_COMMIT_START); spin_unlock(&info->trans_lock); return ret; } int btrfs_transaction_blocked(struct btrfs_fs_info *info) { + struct btrfs_transaction *trans; int ret = 0; + spin_lock(&info->trans_lock); - if (info->running_transaction) - ret = info->running_transaction->blocked; + trans = info->running_transaction; + if (trans) + ret = is_transaction_blocked(trans); spin_unlock(&info->trans_lock); return ret; } @@ -1368,7 +1391,8 @@ int btrfs_transaction_blocked(struct btrfs_fs_info *info) static void wait_current_trans_commit_start(struct btrfs_root *root, struct btrfs_transaction *trans) { - wait_event(root->fs_info->transaction_blocked_wait, trans->in_commit); + wait_event(root->fs_info->transaction_blocked_wait, + trans->state >= TRANS_STATE_COMMIT_START); } /* @@ -1379,7 +1403,7 @@ static void wait_current_trans_commit_start_and_unblock(struct btrfs_root *root, struct btrfs_transaction *trans) { wait_event(root->fs_info->transaction_wait, - trans->commit_done || (trans->in_commit && !trans->blocked)); + trans->state >= TRANS_STATE_UNBLOCKED); } /* @@ -1484,18 +1508,22 @@ static void cleanup_transaction(struct btrfs_trans_handle *trans, list_del_init(&cur_trans->list); if (cur_trans == root->fs_info->running_transaction) { - root->fs_info->trans_no_join = 1; + cur_trans->state = TRANS_STATE_COMMIT_DOING; spin_unlock(&root->fs_info->trans_lock); wait_event(cur_trans->writer_wait, atomic_read(&cur_trans->num_writers) == 1); spin_lock(&root->fs_info->trans_lock); - root->fs_info->running_transaction = NULL; } spin_unlock(&root->fs_info->trans_lock); btrfs_cleanup_one_transaction(trans->transaction, root); + spin_lock(&root->fs_info->trans_lock); + if (cur_trans == root->fs_info->running_transaction) + root->fs_info->running_transaction = NULL; + spin_unlock(&root->fs_info->trans_lock); + put_transaction(cur_trans); put_transaction(cur_trans); @@ -1507,10 +1535,6 @@ static void cleanup_transaction(struct btrfs_trans_handle *trans, current->journal_info = NULL; kmem_cache_free(btrfs_trans_handle_cachep, trans); - - spin_lock(&root->fs_info->trans_lock); - root->fs_info->trans_no_join = 0; - spin_unlock(&root->fs_info->trans_lock); } static int btrfs_flush_all_pending_stuffs(struct btrfs_trans_handle *trans, @@ -1554,13 +1578,6 @@ static inline void btrfs_wait_delalloc_flush(struct btrfs_fs_info *fs_info) btrfs_wait_all_ordered_extents(fs_info, 1); } -/* - * btrfs_transaction state sequence: - * in_commit = 0, blocked = 0 (initial) - * in_commit = 1, blocked = 1 - * blocked = 0 - * commit_done = 1 - */ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, struct btrfs_root *root) { @@ -1615,9 +1632,9 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, return ret; } - spin_lock(&cur_trans->commit_lock); - if (cur_trans->in_commit) { - spin_unlock(&cur_trans->commit_lock); + spin_lock(&root->fs_info->trans_lock); + if (cur_trans->state >= TRANS_STATE_COMMIT_START) { + spin_unlock(&root->fs_info->trans_lock); atomic_inc(&cur_trans->use_count); ret = btrfs_end_transaction(trans, root); @@ -1628,16 +1645,13 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, return ret; } - trans->transaction->in_commit = 1; - trans->transaction->blocked = 1; - spin_unlock(&cur_trans->commit_lock); + cur_trans->state = TRANS_STATE_COMMIT_START; wake_up(&root->fs_info->transaction_blocked_wait); - spin_lock(&root->fs_info->trans_lock); if (cur_trans->list.prev != &root->fs_info->trans_list) { prev_trans = list_entry(cur_trans->list.prev, struct btrfs_transaction, list); - if (!prev_trans->commit_done) { + if (prev_trans->state != TRANS_STATE_COMPLETED) { atomic_inc(&prev_trans->use_count); spin_unlock(&root->fs_info->trans_lock); @@ -1673,10 +1687,10 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, /* * Ok now we need to make sure to block out any other joins while we * commit the transaction. We could have started a join before setting - * no_join so make sure to wait for num_writers to == 1 again. + * COMMIT_DOING so make sure to wait for num_writers to == 1 again. */ spin_lock(&root->fs_info->trans_lock); - root->fs_info->trans_no_join = 1; + cur_trans->state = TRANS_STATE_COMMIT_DOING; spin_unlock(&root->fs_info->trans_lock); wait_event(cur_trans->writer_wait, atomic_read(&cur_trans->num_writers) == 1); @@ -1803,10 +1817,9 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, memcpy(root->fs_info->super_for_commit, root->fs_info->super_copy, sizeof(*root->fs_info->super_copy)); - trans->transaction->blocked = 0; spin_lock(&root->fs_info->trans_lock); + cur_trans->state = TRANS_STATE_UNBLOCKED; root->fs_info->running_transaction = NULL; - root->fs_info->trans_no_join = 0; spin_unlock(&root->fs_info->trans_lock); mutex_unlock(&root->fs_info->reloc_mutex); @@ -1834,10 +1847,12 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, btrfs_finish_extent_commit(trans, root); - cur_trans->commit_done = 1; - root->fs_info->last_trans_committed = cur_trans->transid; - + /* + * We needn't acquire the lock here because there is no other task + * which can change it. + */ + cur_trans->state = TRANS_STATE_COMPLETED; wake_up(&cur_trans->commit_wait); spin_lock(&root->fs_info->trans_lock); diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h index 0fc45e2..66d2a6c 100644 --- a/fs/btrfs/transaction.h +++ b/fs/btrfs/transaction.h @@ -22,6 +22,16 @@ #include "delayed-ref.h" #include "ctree.h" +enum btrfs_trans_state { + TRANS_STATE_RUNNING = 0, + TRANS_STATE_BLOCKED = 1, + TRANS_STATE_COMMIT_START = 2, + TRANS_STATE_COMMIT_DOING = 3, + TRANS_STATE_UNBLOCKED = 4, + TRANS_STATE_COMPLETED = 5, + TRANS_STATE_MAX = 6, +}; + struct btrfs_transaction { u64 transid; /* @@ -37,10 +47,8 @@ struct btrfs_transaction { atomic_t num_writers; atomic_t use_count; - spinlock_t commit_lock; - int in_commit; - int commit_done; - int blocked; + /* Be protected by fs_info->trans_lock when we want to change it. */ + enum btrfs_trans_state state; struct list_head list; struct extent_io_tree dirty_pages; unsigned long start_time; |