From 40431d6c1288793a682fc6f5e5b5c9d5cac34608 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Wed, 5 Aug 2009 12:57:59 -0400 Subject: [PATCH] Btrfs: optimize set extent bit The Btrfs set_extent_bit call currently searches the rbtree every time it needs to find more extent_state objects to fill the requested operation. This adds a simple test with rb_next to see if the next object in the tree was adjacent to the one we just found. If so, we skip the search and just use the next object. Signed-off-by: Chris Mason --- fs/btrfs/extent_io.c | 15 +++++++++++++-- fs/btrfs/file.c | 2 -- 2 files changed, 13 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 68260180f587..7e5c5a0749e2 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -694,8 +694,8 @@ static int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, BUG_ON(err == -EEXIST); goto out; } - state = rb_entry(node, struct extent_state, rb_node); +hit_next: last_start = state->start; last_end = state->end; @@ -706,6 +706,7 @@ static int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, * Just lock what we found and keep going */ if (state->start == start && state->end <= end) { + struct rb_node *next_node; set = state->state & bits; if (set && exclusive) { *failed_start = state->start; @@ -716,7 +717,17 @@ static int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, merge_state(tree, state); if (last_end == (u64)-1) goto out; + start = last_end + 1; + if (start < end && prealloc && !need_resched()) { + next_node = rb_next(node); + if (next_node) { + state = rb_entry(next_node, struct extent_state, + rb_node); + if (state->start == start) + goto hit_next; + } + } goto search_again; } @@ -852,7 +863,7 @@ int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask) { return set_extent_bit(tree, start, end, - EXTENT_DELALLOC | EXTENT_DIRTY, + EXTENT_DELALLOC | EXTENT_DIRTY | EXTENT_UPTODATE, 0, NULL, mask); } diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 7c3cd248d8d6..a760d97279ac 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -136,8 +136,6 @@ static noinline int dirty_and_release_pages(struct btrfs_trans_handle *trans, btrfs_set_trans_block_group(trans, inode); hint_byte = 0; - set_extent_uptodate(io_tree, start_pos, end_of_last_block, GFP_NOFS); - /* check for reserved extents on each page, we don't want * to reset the delalloc bit on things that already have * extents reserved. -- GitLab