diff options
Diffstat (limited to 'fs/btrfs/delayed-ref.c')
-rw-r--r-- | fs/btrfs/delayed-ref.c | 163 |
1 files changed, 128 insertions, 35 deletions
diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c index da7419e..ae94117 100644 --- a/fs/btrfs/delayed-ref.c +++ b/fs/btrfs/delayed-ref.c @@ -38,17 +38,14 @@ static int comp_tree_refs(struct btrfs_delayed_tree_ref *ref2, struct btrfs_delayed_tree_ref *ref1) { - if (ref1->node.type == BTRFS_TREE_BLOCK_REF_KEY) { - if (ref1->root < ref2->root) - return -1; - if (ref1->root > ref2->root) - return 1; - } else { - if (ref1->parent < ref2->parent) - return -1; - if (ref1->parent > ref2->parent) - return 1; - } + if (ref1->root < ref2->root) + return -1; + if (ref1->root > ref2->root) + return 1; + if (ref1->parent < ref2->parent) + return -1; + if (ref1->parent > ref2->parent) + return 1; return 0; } @@ -85,7 +82,8 @@ static int comp_data_refs(struct btrfs_delayed_data_ref *ref2, * type of the delayed backrefs and content of delayed backrefs. */ static int comp_entry(struct btrfs_delayed_ref_node *ref2, - struct btrfs_delayed_ref_node *ref1) + struct btrfs_delayed_ref_node *ref1, + bool compare_seq) { if (ref1->bytenr < ref2->bytenr) return -1; @@ -102,10 +100,12 @@ static int comp_entry(struct btrfs_delayed_ref_node *ref2, if (ref1->type > ref2->type) return 1; /* merging of sequenced refs is not allowed */ - if (ref1->seq < ref2->seq) - return -1; - if (ref1->seq > ref2->seq) - return 1; + if (compare_seq) { + if (ref1->seq < ref2->seq) + return -1; + if (ref1->seq > ref2->seq) + return 1; + } if (ref1->type == BTRFS_TREE_BLOCK_REF_KEY || ref1->type == BTRFS_SHARED_BLOCK_REF_KEY) { return comp_tree_refs(btrfs_delayed_node_to_tree_ref(ref2), @@ -139,7 +139,7 @@ static struct btrfs_delayed_ref_node *tree_insert(struct rb_root *root, entry = rb_entry(parent_node, struct btrfs_delayed_ref_node, rb_node); - cmp = comp_entry(entry, ins); + cmp = comp_entry(entry, ins, 1); if (cmp < 0) p = &(*p)->rb_left; else if (cmp > 0) @@ -233,6 +233,114 @@ int btrfs_delayed_ref_lock(struct btrfs_trans_handle *trans, return 0; } +static void inline drop_delayed_ref(struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_node *ref) +{ + rb_erase(&ref->rb_node, &delayed_refs->root); + ref->in_tree = 0; + btrfs_put_delayed_ref(ref); + delayed_refs->num_entries--; + if (trans->delayed_ref_updates) + trans->delayed_ref_updates--; +} + +static int merge_ref(struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_node *ref, u64 seq) +{ + struct rb_node *node; + int merged = 0; + int mod = 0; + int done = 0; + + node = rb_prev(&ref->rb_node); + while (node) { + struct btrfs_delayed_ref_node *next; + + next = rb_entry(node, struct btrfs_delayed_ref_node, rb_node); + node = rb_prev(node); + if (next->bytenr != ref->bytenr) + break; + if (seq && next->seq >= seq) + break; + if (comp_entry(ref, next, 0)) + continue; + + if (ref->action == next->action) { + mod = next->ref_mod; + } else { + if (ref->ref_mod < next->ref_mod) { + struct btrfs_delayed_ref_node *tmp; + + tmp = ref; + ref = next; + next = tmp; + done = 1; + } + mod = -next->ref_mod; + } + + merged++; + drop_delayed_ref(trans, delayed_refs, next); + ref->ref_mod += mod; + if (ref->ref_mod == 0) { + drop_delayed_ref(trans, delayed_refs, ref); + break; + } else { + /* + * You can't have multiples of the same ref on a tree + * block. + */ + WARN_ON(ref->type == BTRFS_TREE_BLOCK_REF_KEY || + ref->type == BTRFS_SHARED_BLOCK_REF_KEY); + } + + if (done) + break; + node = rb_prev(&ref->rb_node); + } + + return merged; +} + +void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_head *head) +{ + struct rb_node *node; + u64 seq = 0; + + spin_lock(&fs_info->tree_mod_seq_lock); + if (!list_empty(&fs_info->tree_mod_seq_list)) { + struct seq_list *elem; + + elem = list_first_entry(&fs_info->tree_mod_seq_list, + struct seq_list, list); + seq = elem->seq; + } + spin_unlock(&fs_info->tree_mod_seq_lock); + + node = rb_prev(&head->node.rb_node); + while (node) { + struct btrfs_delayed_ref_node *ref; + + ref = rb_entry(node, struct btrfs_delayed_ref_node, + rb_node); + if (ref->bytenr != head->node.bytenr) + break; + + /* We can't merge refs that are outside of our seq count */ + if (seq && ref->seq >= seq) + break; + if (merge_ref(trans, delayed_refs, ref, seq)) + node = rb_prev(&head->node.rb_node); + else + node = rb_prev(node); + } +} + int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info, struct btrfs_delayed_ref_root *delayed_refs, u64 seq) @@ -336,18 +444,11 @@ update_existing_ref(struct btrfs_trans_handle *trans, * every changing the extent allocation tree. */ existing->ref_mod--; - if (existing->ref_mod == 0) { - rb_erase(&existing->rb_node, - &delayed_refs->root); - existing->in_tree = 0; - btrfs_put_delayed_ref(existing); - delayed_refs->num_entries--; - if (trans->delayed_ref_updates) - trans->delayed_ref_updates--; - } else { + if (existing->ref_mod == 0) + drop_delayed_ref(trans, delayed_refs, existing); + else WARN_ON(existing->type == BTRFS_TREE_BLOCK_REF_KEY || existing->type == BTRFS_SHARED_BLOCK_REF_KEY); - } } else { WARN_ON(existing->type == BTRFS_TREE_BLOCK_REF_KEY || existing->type == BTRFS_SHARED_BLOCK_REF_KEY); @@ -662,9 +763,6 @@ int btrfs_add_delayed_tree_ref(struct btrfs_fs_info *fs_info, add_delayed_tree_ref(fs_info, trans, &ref->node, bytenr, num_bytes, parent, ref_root, level, action, for_cow); - if (!need_ref_seq(for_cow, ref_root) && - waitqueue_active(&fs_info->tree_mod_seq_wait)) - wake_up(&fs_info->tree_mod_seq_wait); spin_unlock(&delayed_refs->lock); if (need_ref_seq(for_cow, ref_root)) btrfs_qgroup_record_ref(trans, &ref->node, extent_op); @@ -713,9 +811,6 @@ int btrfs_add_delayed_data_ref(struct btrfs_fs_info *fs_info, add_delayed_data_ref(fs_info, trans, &ref->node, bytenr, num_bytes, parent, ref_root, owner, offset, action, for_cow); - if (!need_ref_seq(for_cow, ref_root) && - waitqueue_active(&fs_info->tree_mod_seq_wait)) - wake_up(&fs_info->tree_mod_seq_wait); spin_unlock(&delayed_refs->lock); if (need_ref_seq(for_cow, ref_root)) btrfs_qgroup_record_ref(trans, &ref->node, extent_op); @@ -744,8 +839,6 @@ int btrfs_add_delayed_extent_op(struct btrfs_fs_info *fs_info, num_bytes, BTRFS_UPDATE_DELAYED_HEAD, extent_op->is_data); - if (waitqueue_active(&fs_info->tree_mod_seq_wait)) - wake_up(&fs_info->tree_mod_seq_wait); spin_unlock(&delayed_refs->lock); return 0; } |