btrfs: reada: Pass reada_extent into __readahead_hook directly
reada_start_machine_dev() already have reada_extent pointer, pass
it into __readahead_hook() directly instead of search radix_tree
will make code run faster.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/reada.c b/fs/btrfs/reada.c
index f7642e56..203bec4 100644
--- a/fs/btrfs/reada.c
+++ b/fs/btrfs/reada.c
@@ -105,33 +105,21 @@
/* recurses */
/* in case of err, eb might be NULL */
-static int __readahead_hook(struct btrfs_root *root, struct extent_buffer *eb,
- u64 start, int err)
+static void __readahead_hook(struct btrfs_root *root, struct reada_extent *re,
+ struct extent_buffer *eb, u64 start, int err)
{
int level = 0;
int nritems;
int i;
u64 bytenr;
u64 generation;
- struct reada_extent *re;
struct btrfs_fs_info *fs_info = root->fs_info;
struct list_head list;
- unsigned long index = start >> PAGE_CACHE_SHIFT;
struct btrfs_device *for_dev;
if (eb)
level = btrfs_header_level(eb);
- /* find extent */
- spin_lock(&fs_info->reada_lock);
- re = radix_tree_lookup(&fs_info->reada_tree, index);
- if (re)
- re->refcnt++;
- spin_unlock(&fs_info->reada_lock);
-
- if (!re)
- return -1;
-
spin_lock(&re->lock);
/*
* just take the full list from the extent. afterwards we
@@ -221,11 +209,11 @@
reada_extent_put(fs_info, re); /* one ref for each entry */
}
- reada_extent_put(fs_info, re); /* our ref */
+
if (for_dev)
atomic_dec(&for_dev->reada_in_flight);
- return 0;
+ return;
}
/*
@@ -235,12 +223,27 @@
int btree_readahead_hook(struct btrfs_root *root, struct extent_buffer *eb,
u64 start, int err)
{
- int ret;
+ int ret = 0;
+ struct reada_extent *re;
+ struct btrfs_fs_info *fs_info = root->fs_info;
- ret = __readahead_hook(root, eb, start, err);
+ /* find extent */
+ spin_lock(&fs_info->reada_lock);
+ re = radix_tree_lookup(&fs_info->reada_tree,
+ start >> PAGE_CACHE_SHIFT);
+ if (re)
+ re->refcnt++;
+ spin_unlock(&fs_info->reada_lock);
+ if (!re) {
+ ret = -1;
+ goto start_machine;
+ }
- reada_start_machine(root->fs_info);
+ __readahead_hook(fs_info, re, eb, start, err);
+ reada_extent_put(fs_info, re); /* our ref */
+start_machine:
+ reada_start_machine(fs_info);
return ret;
}
@@ -721,9 +724,9 @@
ret = reada_tree_block_flagged(fs_info->extent_root, logical,
mirror_num, &eb);
if (ret)
- __readahead_hook(fs_info->extent_root, NULL, logical, ret);
+ __readahead_hook(fs_info->extent_root, re, NULL, logical, ret);
else if (eb)
- __readahead_hook(fs_info->extent_root, eb, eb->start, ret);
+ __readahead_hook(fs_info->extent_root, re, eb, eb->start, ret);
if (eb)
free_extent_buffer(eb);