From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from aserp1040.oracle.com ([141.146.126.69]:34021 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751048AbaB0JgC (ORCPT ); Thu, 27 Feb 2014 04:36:02 -0500 From: Liu Bo To: linux-btrfs@vger.kernel.org Cc: Wang Shilong Subject: [PATCH 2/2 v3] Btrfs: check if directory has already been created smarter Date: Thu, 27 Feb 2014 17:35:44 +0800 Message-Id: <1393493744-19294-1-git-send-email-bo.li.liu@oracle.com> In-Reply-To: <1393487254-17978-2-git-send-email-bo.li.liu@oracle.com> References: <1393487254-17978-2-git-send-email-bo.li.liu@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: Currently to check whether a directory has been created, we search DIR_INDEX items one by one to check if children has been processed. Try to picture such a scenario: . |-- dir (ino X) |-- foo_1 (ino X+1) |-- ... |-- foo_k (ino X+k) With the current way, we have to check all the k DIR_INDEX items to find it is a fresh new one. So this introduced a rbtree to store those directories which are created out of order, and in the above case, we just need an O(log n) search instead of O(n) search. Signed-off-by: Liu Bo --- v3: fix typo, s/O(1)/O(n)/g, thanks Wang Shilong. v2: fix wrong patch name. fs/btrfs/send.c | 87 ++++++++++++++++++++++++++++----------------------------- 1 file changed, 43 insertions(+), 44 deletions(-) diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index 33063d1..fcad93c 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -175,6 +175,9 @@ struct send_ctx { * own move/rename can be performed. */ struct rb_root waiting_dir_moves; + + /* directories which are created out of order, check did_create_dir() */ + struct rb_root out_of_order; }; struct pending_dir_move { @@ -2494,56 +2497,40 @@ out: */ static int did_create_dir(struct send_ctx *sctx, u64 dir) { - int ret = 0; - struct btrfs_path *path = NULL; - struct btrfs_key key; - struct btrfs_key found_key; - struct btrfs_key di_key; - struct extent_buffer *eb; - struct btrfs_dir_item *di; - int slot; + struct rb_node **p = &sctx->out_of_order.rb_node; + struct rb_node *parent = NULL; + struct send_dir_node *entry = NULL; + int cur_is_dir = !!(dir == sctx->cur_ino); - path = alloc_path_for_send(); - if (!path) { - ret = -ENOMEM; - goto out; - } + verbose_printk("dir=%llu cur_ino=%llu send_progress=%llu\n", + dir, sctx->cur_ino, sctx->send_progress); - key.objectid = dir; - key.type = BTRFS_DIR_INDEX_KEY; - key.offset = 0; - while (1) { - ret = btrfs_search_slot_for_read(sctx->send_root, &key, path, - 1, 0); - if (ret < 0) - goto out; - if (!ret) { - eb = path->nodes[0]; - slot = path->slots[0]; - btrfs_item_key_to_cpu(eb, &found_key, slot); - } - if (ret || found_key.objectid != key.objectid || - found_key.type != key.type) { - ret = 0; - goto out; + while (*p) { + parent = *p; + entry = rb_entry(parent, struct send_dir_node, node); + if (dir < entry->ino) { + p = &(*p)->rb_left; + } else if (dir > entry->ino) { + p = &(*p)->rb_right; + } else { + if (cur_is_dir) { + rb_erase(&entry->node, &sctx->out_of_order); + kfree(entry); + } + return 1; } + } - di = btrfs_item_ptr(eb, slot, struct btrfs_dir_item); - btrfs_dir_item_key_to_cpu(eb, di, &di_key); - - if (di_key.type != BTRFS_ROOT_ITEM_KEY && - di_key.objectid < sctx->send_progress) { - ret = 1; - goto out; - } + if (!cur_is_dir) { + entry = kmalloc(sizeof(*entry), GFP_NOFS); + if (!entry) + return -ENOMEM; + entry->ino = dir; - key.offset = found_key.offset + 1; - btrfs_release_path(path); + rb_link_node(&entry->node, parent, p); + rb_insert_color(&entry->node, &sctx->out_of_order); } - -out: - btrfs_free_path(path); - return ret; + return 0; } /* @@ -5340,6 +5327,7 @@ long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_) sctx->pending_dir_moves = RB_ROOT; sctx->waiting_dir_moves = RB_ROOT; + sctx->out_of_order = RB_ROOT; sctx->clone_roots = vzalloc(sizeof(struct clone_root) * (arg->clone_sources_count + 1)); @@ -5477,6 +5465,17 @@ out: kfree(dm); } + WARN_ON(sctx && !ret && !RB_EMPTY_ROOT(&sctx->out_of_order)); + while (sctx && !RB_EMPTY_ROOT(&sctx->out_of_order)) { + struct rb_node *n; + struct send_dir_node *entry; + + n = rb_first(&sctx->out_of_order); + entry = rb_entry(n, struct send_dir_node, node); + rb_erase(&entry->node, &sctx->out_of_order); + kfree(entry); + } + if (sort_clone_roots) { for (i = 0; i < sctx->clone_roots_cnt; i++) btrfs_root_dec_send_in_progress( -- 1.8.2.1