From 7fdd29d02e0ab595a857fe9c7b71e752ff665372 Mon Sep 17 00:00:00 2001 From: Filipe David Borba Manana Date: Fri, 24 Jan 2014 17:42:09 +0000 Subject: [PATCH] Btrfs: make send's file extent item search more efficient Instead of looking for a file extent item, process it, release the path and do a btree search for the next file extent item, just process all file extent items in a leaf without intermediate btree searches. This way we save cpu and we're not blocking other tasks or affecting concurrency on the btree, because send's paths use the commit root and skip btree node/leaf locking. Signed-off-by: Filipe David Borba Manana Signed-off-by: Josef Bacik Signed-off-by: Chris Mason --- fs/btrfs/send.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index c96e879..4d31f72 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -4573,17 +4573,25 @@ static int process_all_extents(struct send_ctx *sctx) key.objectid = sctx->cmp_key->objectid; key.type = BTRFS_EXTENT_DATA_KEY; key.offset = 0; - while (1) { - ret = btrfs_search_slot_for_read(root, &key, path, 1, 0); - if (ret < 0) - goto out; - if (ret) { - ret = 0; - goto out; - } + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + goto out; + while (1) { eb = path->nodes[0]; slot = path->slots[0]; + + if (slot >= btrfs_header_nritems(eb)) { + ret = btrfs_next_leaf(root, path); + if (ret < 0) { + goto out; + } else if (ret > 0) { + ret = 0; + break; + } + continue; + } + btrfs_item_key_to_cpu(eb, &found_key, slot); if (found_key.objectid != key.objectid || @@ -4596,8 +4604,7 @@ static int process_all_extents(struct send_ctx *sctx) if (ret < 0) goto out; - btrfs_release_path(path); - key.offset = found_key.offset + 1; + path->slots[0]++; } out: -- 2.7.4