This patch does two things, first it only does one call to
btrfs_buffer_uptodate() with the gen specified instead of once with 0 and then
again with gen specified. The other thing is to call btrfs_read_buffer() on the
buffer we've found instead of dropping it and then calling read_tree_block().
This will keep us from doing yet another radix tree lookup for a buffer we've
already found. Thanks,
Signed-off-by: Josef Bacik <jba...@fusionio.com>
---
fs/btrfs/ctree.c | 47 ++++++++++++++++++++---------------------------
1 files changed, 20 insertions(+), 27 deletions(-)
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 1c9dc71..c85cde7 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -2359,35 +2359,28 @@ read_block_for_search(struct btrfs_trans_handle *trans,
tmp = btrfs_find_tree_block(root, blocknr, blocksize);
if (tmp) {
/* first we do an atomic uptodate check */
- if (btrfs_buffer_uptodate(tmp, 0, 1) > 0) {
- if (btrfs_buffer_uptodate(tmp, gen, 1) > 0) {
- /*
- * we found an up to date block without
- * sleeping, return
- * right away
- */
- *eb_ret = tmp;
- return 0;
- }
- /* the pages were up to date, but we failed
- * the generation number check. Do a full
- * read for the generation number that is correct.
- * We must do this without dropping locks so
- * we can trust our generation number
- */
- free_extent_buffer(tmp);
- btrfs_set_path_blocking(p);
+ if (btrfs_buffer_uptodate(tmp, gen, 1) > 0) {
+ *eb_ret = tmp;
+ return 0;
+ }
- /* now we're allowed to do a blocking uptodate check */
- tmp = read_tree_block(root, blocknr, blocksize, gen);
- if (tmp && btrfs_buffer_uptodate(tmp, gen, 0) > 0) {
- *eb_ret = tmp;
- return 0;
- }
- free_extent_buffer(tmp);
- btrfs_release_path(p);
- return -EIO;
+ /* the pages were up to date, but we failed
+ * the generation number check. Do a full
+ * read for the generation number that is correct.
+ * We must do this without dropping locks so
+ * we can trust our generation number
+ */
+ btrfs_set_path_blocking(p);
+
+ /* now we're allowed to do a blocking uptodate check */
+ ret = btrfs_read_buffer(tmp, gen);
+ if (!ret) {
+ *eb_ret = tmp;
+ return 0;
}
+ free_extent_buffer(tmp);
+ btrfs_release_path(p);
+ return -EIO;
}
/*
--
1.7.7.6
--
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