Btrfs: cache the extent state everywhere we possibly can V2

This patch just goes through and fixes everybody that does

lock_extent()
blah
unlock_extent()

to use

lock_extent_bits()
blah
unlock_extent_cached()

and pass around a extent_state so we only have to do the searches once per
function.  This gives me about a 3 mb/s boots on my random write test.  I have
not converted some things, like the relocation and ioctl's, since they aren't
heavily used and the relocation stuff is in the middle of being re-written.  I
also changed the clear_extent_bit() to only unset the cached state if we are
clearing EXTENT_LOCKED and related stuff, so we can do things like this

lock_extent_bits()
clear delalloc bits
unlock_extent_cached()

without losing our cached state.  I tested this thoroughly and turned on
LEAK_DEBUG to make sure we weren't leaking extent states, everything worked out
fine.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 9 insertions, 6 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 0427183e3e05..11d0ad30e203 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -263,13 +263,15 @@ static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 static int verify_parent_transid(struct extent_io_tree *io_tree,
 				 struct extent_buffer *eb, u64 parent_transid)
 {
+	struct extent_state *cached_state = NULL;
 	int ret;
 
 	if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
 		return 0;
 
-	lock_extent(io_tree, eb->start, eb->start + eb->len - 1, GFP_NOFS);
-	if (extent_buffer_uptodate(io_tree, eb) &&
+	lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
+			 0, &cached_state, GFP_NOFS);
+	if (extent_buffer_uptodate(io_tree, eb, cached_state) &&
 	    btrfs_header_generation(eb) == parent_transid) {
 		ret = 0;
 		goto out;
@@ -282,10 +284,10 @@ static int verify_parent_transid(struct extent_io_tree *io_tree,
 		       (unsigned long long)btrfs_header_generation(eb));
 	}
 	ret = 1;
-	clear_extent_buffer_uptodate(io_tree, eb);
+	clear_extent_buffer_uptodate(io_tree, eb, &cached_state);
 out:
-	unlock_extent(io_tree, eb->start, eb->start + eb->len - 1,
-		      GFP_NOFS);
+	unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
+			     &cached_state, GFP_NOFS);
 	return ret;
 }
 
@@ -2497,7 +2499,8 @@ int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
 	int ret;
 	struct inode *btree_inode = buf->first_page->mapping->host;
 
-	ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf);
+	ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf,
+				     NULL);
 	if (!ret)
 		return ret;