diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/btrfs/delayed-ref.h | 9 | ||||
| -rw-r--r-- | fs/btrfs/extent-tree.c | 60 | ||||
| -rw-r--r-- | fs/btrfs/transaction.c | 6 |
3 files changed, 70 insertions, 5 deletions
diff --git a/fs/btrfs/delayed-ref.h b/fs/btrfs/delayed-ref.h index c9d703693df0..23bdeb8502a6 100644 --- a/fs/btrfs/delayed-ref.h +++ b/fs/btrfs/delayed-ref.h @@ -132,6 +132,15 @@ struct btrfs_delayed_ref_root { unsigned long num_heads_ready; /* + * bumped when someone is making progress on the delayed + * refs, so that other procs know they are just adding to + * contention intead of helping + */ + atomic_t procs_running_refs; + atomic_t ref_seq; + wait_queue_head_t wait; + + /* * set when the tree is flushing before a transaction commit, * used by the throttling code to decide if new updates need * to be run right away diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index f13402104c96..87b0e856b6d0 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -2438,6 +2438,16 @@ int btrfs_delayed_refs_qgroup_accounting(struct btrfs_trans_handle *trans, return ret; } +static int refs_newer(struct btrfs_delayed_ref_root *delayed_refs, int seq, + int count) +{ + int val = atomic_read(&delayed_refs->ref_seq); + + if (val < seq || val >= seq + count) + return 1; + return 0; +} + /* * this starts processing the delayed reference count updates and * extent insertions we have queued up so far. count can be @@ -2472,6 +2482,44 @@ int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, delayed_refs = &trans->transaction->delayed_refs; INIT_LIST_HEAD(&cluster); + if (count == 0) { + count = delayed_refs->num_entries * 2; + run_most = 1; + } + + if (!run_all && !run_most) { + int old; + int seq = atomic_read(&delayed_refs->ref_seq); + +progress: + old = atomic_cmpxchg(&delayed_refs->procs_running_refs, 0, 1); + if (old) { + DEFINE_WAIT(__wait); + if (delayed_refs->num_entries < 16348) + return 0; + + prepare_to_wait(&delayed_refs->wait, &__wait, + TASK_UNINTERRUPTIBLE); + + old = atomic_cmpxchg(&delayed_refs->procs_running_refs, 0, 1); + if (old) { + schedule(); + finish_wait(&delayed_refs->wait, &__wait); + + if (!refs_newer(delayed_refs, seq, 256)) + goto progress; + else + return 0; + } else { + finish_wait(&delayed_refs->wait, &__wait); + goto again; + } + } + + } else { + atomic_inc(&delayed_refs->procs_running_refs); + } + again: loops = 0; spin_lock(&delayed_refs->lock); @@ -2480,10 +2528,6 @@ again: delayed_refs->run_delayed_start = find_middle(&delayed_refs->root); #endif - if (count == 0) { - count = delayed_refs->num_entries * 2; - run_most = 1; - } while (1) { if (!(run_all || run_most) && delayed_refs->num_heads_ready < 64) @@ -2505,9 +2549,12 @@ again: if (ret < 0) { spin_unlock(&delayed_refs->lock); btrfs_abort_transaction(trans, root, ret); + atomic_dec(&delayed_refs->procs_running_refs); return ret; } + atomic_add(ret, &delayed_refs->ref_seq); + count -= min_t(unsigned long, ret, count); if (count == 0) @@ -2576,6 +2623,11 @@ again: goto again; } out: + atomic_dec(&delayed_refs->procs_running_refs); + smp_mb(); + if (waitqueue_active(&delayed_refs->wait)) + wake_up(&delayed_refs->wait); + spin_unlock(&delayed_refs->lock); assert_qgroups_uptodate(trans); return 0; diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index a065dec0e330..1e7f176bd211 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -156,6 +156,9 @@ loop: 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); + init_waitqueue_head(&cur_trans->delayed_refs.wait); INIT_LIST_HEAD(&cur_trans->pending_snapshots); list_add_tail(&cur_trans->list, &fs_info->trans_list); @@ -577,7 +580,7 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, if (!list_empty(&trans->new_bgs)) btrfs_create_pending_block_groups(trans, root); - while (count < 2) { + while (count < 1) { unsigned long cur = trans->delayed_ref_updates; trans->delayed_ref_updates = 0; if (cur && @@ -589,6 +592,7 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, } count++; } + btrfs_trans_release_metadata(trans, root); trans->block_rsv = NULL; |