X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=fs%2Fbtrfs%2Fdelayed-ref.c;h=f3bff89eecf09346e2eb49b4ffeb861f35e33d4b;hb=151b628f104566a450125a6a0f6775a35bde58d6;hp=e4d467be2dd44d131977d64c3029af3fc9d99ce3;hpb=861e66d3418a90f57b31a50110fc70b23569c551;p=~andy%2Flinux diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c index e4d467be2dd..f3bff89eecf 100644 --- a/fs/btrfs/delayed-ref.c +++ b/fs/btrfs/delayed-ref.c @@ -161,35 +161,61 @@ static struct btrfs_delayed_ref_node *tree_insert(struct rb_root *root, return NULL; } +/* insert a new ref to head ref rbtree */ +static struct btrfs_delayed_ref_head *htree_insert(struct rb_root *root, + struct rb_node *node) +{ + struct rb_node **p = &root->rb_node; + struct rb_node *parent_node = NULL; + struct btrfs_delayed_ref_head *entry; + struct btrfs_delayed_ref_head *ins; + u64 bytenr; + + ins = rb_entry(node, struct btrfs_delayed_ref_head, href_node); + bytenr = ins->node.bytenr; + while (*p) { + parent_node = *p; + entry = rb_entry(parent_node, struct btrfs_delayed_ref_head, + href_node); + + if (bytenr < entry->node.bytenr) + p = &(*p)->rb_left; + else if (bytenr > entry->node.bytenr) + p = &(*p)->rb_right; + else + return entry; + } + + rb_link_node(node, parent_node, p); + rb_insert_color(node, root); + return NULL; +} + /* * find an head entry based on bytenr. This returns the delayed ref * head if it was able to find one, or NULL if nothing was in that spot. * If return_bigger is given, the next bigger entry is returned if no exact * match is found. */ -static struct btrfs_delayed_ref_node *find_ref_head(struct rb_root *root, - u64 bytenr, - struct btrfs_delayed_ref_node **last, - int return_bigger) +static struct btrfs_delayed_ref_head * +find_ref_head(struct rb_root *root, u64 bytenr, + struct btrfs_delayed_ref_head **last, int return_bigger) { struct rb_node *n; - struct btrfs_delayed_ref_node *entry; + struct btrfs_delayed_ref_head *entry; int cmp = 0; again: n = root->rb_node; entry = NULL; while (n) { - entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node); - WARN_ON(!entry->in_tree); + entry = rb_entry(n, struct btrfs_delayed_ref_head, href_node); if (last) *last = entry; - if (bytenr < entry->bytenr) + if (bytenr < entry->node.bytenr) cmp = -1; - else if (bytenr > entry->bytenr) - cmp = 1; - else if (!btrfs_delayed_ref_is_head(entry)) + else if (bytenr > entry->node.bytenr) cmp = 1; else cmp = 0; @@ -203,12 +229,12 @@ again: } if (entry && return_bigger) { if (cmp > 0) { - n = rb_next(&entry->rb_node); + n = rb_next(&entry->href_node); if (!n) n = rb_first(root); - entry = rb_entry(n, struct btrfs_delayed_ref_node, - rb_node); - bytenr = entry->bytenr; + entry = rb_entry(n, struct btrfs_delayed_ref_head, + href_node); + bytenr = entry->node.bytenr; return_bigger = 0; goto again; } @@ -243,33 +269,38 @@ int btrfs_delayed_ref_lock(struct btrfs_trans_handle *trans, static inline void drop_delayed_ref(struct btrfs_trans_handle *trans, struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_head *head, struct btrfs_delayed_ref_node *ref) { - rb_erase(&ref->rb_node, &delayed_refs->root); + if (btrfs_delayed_ref_is_head(ref)) { + head = btrfs_delayed_node_to_head(ref); + rb_erase(&head->href_node, &delayed_refs->href_root); + } else { + assert_spin_locked(&head->lock); + rb_erase(&ref->rb_node, &head->ref_root); + } ref->in_tree = 0; btrfs_put_delayed_ref(ref); - delayed_refs->num_entries--; + atomic_dec(&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_head *head, 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) { + node = rb_next(&ref->rb_node); + while (!done && 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; + node = rb_next(node); if (seq && next->seq >= seq) break; if (comp_entry(ref, next, 0)) @@ -289,12 +320,11 @@ static int merge_ref(struct btrfs_trans_handle *trans, mod = -next->ref_mod; } - merged++; - drop_delayed_ref(trans, delayed_refs, next); + drop_delayed_ref(trans, delayed_refs, head, next); ref->ref_mod += mod; if (ref->ref_mod == 0) { - drop_delayed_ref(trans, delayed_refs, ref); - break; + drop_delayed_ref(trans, delayed_refs, head, ref); + done = 1; } else { /* * You can't have multiples of the same ref on a tree @@ -303,13 +333,8 @@ static int merge_ref(struct btrfs_trans_handle *trans, 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; + return done; } void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans, @@ -320,6 +345,14 @@ void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans, struct rb_node *node; u64 seq = 0; + assert_spin_locked(&head->lock); + /* + * We don't have too much refs to merge in the case of delayed data + * refs. + */ + if (head->is_data) + return; + spin_lock(&fs_info->tree_mod_seq_lock); if (!list_empty(&fs_info->tree_mod_seq_list)) { struct seq_list *elem; @@ -330,22 +363,19 @@ void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans, } spin_unlock(&fs_info->tree_mod_seq_lock); - node = rb_prev(&head->node.rb_node); + node = rb_first(&head->ref_root); 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); + if (merge_ref(trans, delayed_refs, head, ref, seq)) + node = rb_first(&head->ref_root); else - node = rb_prev(node); + node = rb_next(&ref->rb_node); } } @@ -373,71 +403,52 @@ int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info, return ret; } -int btrfs_find_ref_cluster(struct btrfs_trans_handle *trans, - struct list_head *cluster, u64 start) +struct btrfs_delayed_ref_head * +btrfs_select_ref_head(struct btrfs_trans_handle *trans) { - int count = 0; struct btrfs_delayed_ref_root *delayed_refs; - struct rb_node *node; - struct btrfs_delayed_ref_node *ref; struct btrfs_delayed_ref_head *head; + u64 start; + bool loop = false; delayed_refs = &trans->transaction->delayed_refs; - if (start == 0) { - node = rb_first(&delayed_refs->root); - } else { - ref = NULL; - find_ref_head(&delayed_refs->root, start + 1, &ref, 1); - if (ref) { - node = &ref->rb_node; - } else - node = rb_first(&delayed_refs->root); - } + again: - while (node && count < 32) { - ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node); - if (btrfs_delayed_ref_is_head(ref)) { - head = btrfs_delayed_node_to_head(ref); - if (list_empty(&head->cluster)) { - list_add_tail(&head->cluster, cluster); - delayed_refs->run_delayed_start = - head->node.bytenr; - count++; - - WARN_ON(delayed_refs->num_heads_ready == 0); - delayed_refs->num_heads_ready--; - } else if (count) { - /* the goal of the clustering is to find extents - * that are likely to end up in the same extent - * leaf on disk. So, we don't want them spread - * all over the tree. Stop now if we've hit - * a head that was already in use - */ - break; - } - } - node = rb_next(node); - } - if (count) { - return 0; - } else if (start) { - /* - * we've gone to the end of the rbtree without finding any - * clusters. start from the beginning and try again - */ + start = delayed_refs->run_delayed_start; + head = find_ref_head(&delayed_refs->href_root, start, NULL, 1); + if (!head && !loop) { + delayed_refs->run_delayed_start = 0; start = 0; - node = rb_first(&delayed_refs->root); - goto again; + loop = true; + head = find_ref_head(&delayed_refs->href_root, start, NULL, 1); + if (!head) + return NULL; + } else if (!head && loop) { + return NULL; } - return 1; -} -void btrfs_release_ref_cluster(struct list_head *cluster) -{ - struct list_head *pos, *q; + while (head->processing) { + struct rb_node *node; + + node = rb_next(&head->href_node); + if (!node) { + if (loop) + return NULL; + delayed_refs->run_delayed_start = 0; + start = 0; + loop = true; + goto again; + } + head = rb_entry(node, struct btrfs_delayed_ref_head, + href_node); + } - list_for_each_safe(pos, q, cluster) - list_del_init(pos); + head->processing = 1; + WARN_ON(delayed_refs->num_heads_ready == 0); + delayed_refs->num_heads_ready--; + delayed_refs->run_delayed_start = head->node.bytenr + + head->node.num_bytes; + return head; } /* @@ -451,6 +462,7 @@ void btrfs_release_ref_cluster(struct list_head *cluster) static noinline void update_existing_ref(struct btrfs_trans_handle *trans, struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_head *head, struct btrfs_delayed_ref_node *existing, struct btrfs_delayed_ref_node *update) { @@ -463,7 +475,7 @@ update_existing_ref(struct btrfs_trans_handle *trans, */ existing->ref_mod--; if (existing->ref_mod == 0) - drop_delayed_ref(trans, delayed_refs, existing); + drop_delayed_ref(trans, delayed_refs, head, existing); else WARN_ON(existing->type == BTRFS_TREE_BLOCK_REF_KEY || existing->type == BTRFS_SHARED_BLOCK_REF_KEY); @@ -533,9 +545,13 @@ update_existing_head_ref(struct btrfs_delayed_ref_node *existing, } } /* - * update the reference mod on the head to reflect this new operation + * update the reference mod on the head to reflect this new operation, + * only need the lock for this case cause we could be processing it + * currently, for refs we just added we know we're a-ok. */ + spin_lock(&existing_ref->lock); existing->ref_mod += update->ref_mod; + spin_unlock(&existing_ref->lock); } /* @@ -543,13 +559,13 @@ update_existing_head_ref(struct btrfs_delayed_ref_node *existing, * this does all the dirty work in terms of maintaining the correct * overall modification count. */ -static noinline void add_delayed_ref_head(struct btrfs_fs_info *fs_info, - struct btrfs_trans_handle *trans, - struct btrfs_delayed_ref_node *ref, - u64 bytenr, u64 num_bytes, - int action, int is_data) +static noinline struct btrfs_delayed_ref_head * +add_delayed_ref_head(struct btrfs_fs_info *fs_info, + struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_node *ref, u64 bytenr, + u64 num_bytes, int action, int is_data) { - struct btrfs_delayed_ref_node *existing; + struct btrfs_delayed_ref_head *existing; struct btrfs_delayed_ref_head *head_ref = NULL; struct btrfs_delayed_ref_root *delayed_refs; int count_mod = 1; @@ -596,38 +612,43 @@ static noinline void add_delayed_ref_head(struct btrfs_fs_info *fs_info, head_ref = btrfs_delayed_node_to_head(ref); head_ref->must_insert_reserved = must_insert_reserved; head_ref->is_data = is_data; + head_ref->ref_root = RB_ROOT; + head_ref->processing = 0; - INIT_LIST_HEAD(&head_ref->cluster); + spin_lock_init(&head_ref->lock); mutex_init(&head_ref->mutex); trace_add_delayed_ref_head(ref, head_ref, action); - existing = tree_insert(&delayed_refs->root, &ref->rb_node); - + existing = htree_insert(&delayed_refs->href_root, + &head_ref->href_node); if (existing) { - update_existing_head_ref(existing, ref); + update_existing_head_ref(&existing->node, ref); /* * we've updated the existing ref, free the newly * allocated ref */ kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref); + head_ref = existing; } else { delayed_refs->num_heads++; delayed_refs->num_heads_ready++; - delayed_refs->num_entries++; + atomic_inc(&delayed_refs->num_entries); trans->delayed_ref_updates++; } + return head_ref; } /* * helper to insert a delayed tree ref into the rbtree. */ -static noinline void add_delayed_tree_ref(struct btrfs_fs_info *fs_info, - struct btrfs_trans_handle *trans, - struct btrfs_delayed_ref_node *ref, - u64 bytenr, u64 num_bytes, u64 parent, - u64 ref_root, int level, int action, - int for_cow) +static noinline void +add_delayed_tree_ref(struct btrfs_fs_info *fs_info, + struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_head *head_ref, + struct btrfs_delayed_ref_node *ref, u64 bytenr, + u64 num_bytes, u64 parent, u64 ref_root, int level, + int action, int for_cow) { struct btrfs_delayed_ref_node *existing; struct btrfs_delayed_tree_ref *full_ref; @@ -663,30 +684,33 @@ static noinline void add_delayed_tree_ref(struct btrfs_fs_info *fs_info, trace_add_delayed_tree_ref(ref, full_ref, action); - existing = tree_insert(&delayed_refs->root, &ref->rb_node); - + spin_lock(&head_ref->lock); + existing = tree_insert(&head_ref->ref_root, &ref->rb_node); if (existing) { - update_existing_ref(trans, delayed_refs, existing, ref); + update_existing_ref(trans, delayed_refs, head_ref, existing, + ref); /* * we've updated the existing ref, free the newly * allocated ref */ kmem_cache_free(btrfs_delayed_tree_ref_cachep, full_ref); } else { - delayed_refs->num_entries++; + atomic_inc(&delayed_refs->num_entries); trans->delayed_ref_updates++; } + spin_unlock(&head_ref->lock); } /* * helper to insert a delayed data ref into the rbtree. */ -static noinline void add_delayed_data_ref(struct btrfs_fs_info *fs_info, - struct btrfs_trans_handle *trans, - struct btrfs_delayed_ref_node *ref, - u64 bytenr, u64 num_bytes, u64 parent, - u64 ref_root, u64 owner, u64 offset, - int action, int for_cow) +static noinline void +add_delayed_data_ref(struct btrfs_fs_info *fs_info, + struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_head *head_ref, + struct btrfs_delayed_ref_node *ref, u64 bytenr, + u64 num_bytes, u64 parent, u64 ref_root, u64 owner, + u64 offset, int action, int for_cow) { struct btrfs_delayed_ref_node *existing; struct btrfs_delayed_data_ref *full_ref; @@ -724,19 +748,21 @@ static noinline void add_delayed_data_ref(struct btrfs_fs_info *fs_info, trace_add_delayed_data_ref(ref, full_ref, action); - existing = tree_insert(&delayed_refs->root, &ref->rb_node); - + spin_lock(&head_ref->lock); + existing = tree_insert(&head_ref->ref_root, &ref->rb_node); if (existing) { - update_existing_ref(trans, delayed_refs, existing, ref); + update_existing_ref(trans, delayed_refs, head_ref, existing, + ref); /* * we've updated the existing ref, free the newly * allocated ref */ kmem_cache_free(btrfs_delayed_data_ref_cachep, full_ref); } else { - delayed_refs->num_entries++; + atomic_inc(&delayed_refs->num_entries); trans->delayed_ref_updates++; } + spin_unlock(&head_ref->lock); } /* @@ -775,10 +801,10 @@ int btrfs_add_delayed_tree_ref(struct btrfs_fs_info *fs_info, * insert both the head node and the new ref without dropping * the spin lock */ - add_delayed_ref_head(fs_info, trans, &head_ref->node, bytenr, - num_bytes, action, 0); + head_ref = add_delayed_ref_head(fs_info, trans, &head_ref->node, + bytenr, num_bytes, action, 0); - add_delayed_tree_ref(fs_info, trans, &ref->node, bytenr, + add_delayed_tree_ref(fs_info, trans, head_ref, &ref->node, bytenr, num_bytes, parent, ref_root, level, action, for_cow); spin_unlock(&delayed_refs->lock); @@ -823,10 +849,10 @@ int btrfs_add_delayed_data_ref(struct btrfs_fs_info *fs_info, * insert both the head node and the new ref without dropping * the spin lock */ - add_delayed_ref_head(fs_info, trans, &head_ref->node, bytenr, - num_bytes, action, 1); + head_ref = add_delayed_ref_head(fs_info, trans, &head_ref->node, + bytenr, num_bytes, action, 1); - add_delayed_data_ref(fs_info, trans, &ref->node, bytenr, + add_delayed_data_ref(fs_info, trans, head_ref, &ref->node, bytenr, num_bytes, parent, ref_root, owner, offset, action, for_cow); spin_unlock(&delayed_refs->lock); @@ -869,14 +895,10 @@ int btrfs_add_delayed_extent_op(struct btrfs_fs_info *fs_info, struct btrfs_delayed_ref_head * btrfs_find_delayed_ref_head(struct btrfs_trans_handle *trans, u64 bytenr) { - struct btrfs_delayed_ref_node *ref; struct btrfs_delayed_ref_root *delayed_refs; delayed_refs = &trans->transaction->delayed_refs; - ref = find_ref_head(&delayed_refs->root, bytenr, NULL, 0); - if (ref) - return btrfs_delayed_node_to_head(ref); - return NULL; + return find_ref_head(&delayed_refs->href_root, bytenr, NULL, 0); } void btrfs_delayed_ref_exit(void)