btrfs: reada_extent doesn't need kref for refcount

All increments and decrements are under the same spinlock - have to be,
since they need to protect the radix_tree it's found in.  Just use
int, no need to wank with kref...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 7 insertions, 11 deletions

diff --git a/fs/btrfs/reada.c b/fs/btrfs/reada.c
index 48a4882d8ad5..a955669519a2 100644
--- a/fs/btrfs/reada.c
+++ b/fs/btrfs/reada.c
@@ -68,7 +68,7 @@ struct reada_extent {
         u32                     blocksize;
         int                     err;
         struct list_head        extctl;
-        struct kref             refcnt;
+        int                     refcnt;
         spinlock_t              lock;
         struct reada_zone       *zones[BTRFS_MAX_MIRRORS];
         int                     nzones;
@@ -126,7 +126,7 @@ static int __readahead_hook(struct btrfs_root *root, struct extent_buffer *eb,
         spin_lock(&fs_info->reada_lock);
         re = radix_tree_lookup(&fs_info->reada_tree, index);
         if (re)
-                kref_get(&re->refcnt);
+                re->refcnt++;
         spin_unlock(&fs_info->reada_lock);
 
         if (!re)
@@ -336,7 +336,7 @@ static struct reada_extent *reada_find_extent(struct btrfs_root *root,
         spin_lock(&fs_info->reada_lock);
         re = radix_tree_lookup(&fs_info->reada_tree, index);
         if (re)
-                kref_get(&re->refcnt);
+                re->refcnt++;
         spin_unlock(&fs_info->reada_lock);
 
         if (re)
@@ -352,7 +352,7 @@ static struct reada_extent *reada_find_extent(struct btrfs_root *root,
         re->top = *top;
         INIT_LIST_HEAD(&re->extctl);
         spin_lock_init(&re->lock);
-        kref_init(&re->refcnt);
+        re->refcnt = 1;
 
         /*
          * map block
@@ -398,7 +398,7 @@ static struct reada_extent *reada_find_extent(struct btrfs_root *root,
         if (ret == -EEXIST) {
                 re_exist = radix_tree_lookup(&fs_info->reada_tree, index);
                 BUG_ON(!re_exist);
-                kref_get(&re_exist->refcnt);
+                re_exist->refcnt++;
                 spin_unlock(&fs_info->reada_lock);
                 goto error;
         }
@@ -465,10 +465,6 @@ error:
         return re_exist;
 }
 
-static void reada_kref_dummy(struct kref *kr)
-{
-}
-
 static void reada_extent_put(struct btrfs_fs_info *fs_info,
                              struct reada_extent *re)
 {
@@ -476,7 +472,7 @@ static void reada_extent_put(struct btrfs_fs_info *fs_info,
         unsigned long index = re->logical >> PAGE_CACHE_SHIFT;
 
         spin_lock(&fs_info->reada_lock);
-        if (!kref_put(&re->refcnt, reada_kref_dummy)) {
+        if (--re->refcnt) {
                 spin_unlock(&fs_info->reada_lock);
                 return;
         }
@@ -671,7 +667,7 @@ static int reada_start_machine_dev(struct btrfs_fs_info *fs_info,
                 return 0;
         }
         dev->reada_next = re->logical + re->blocksize;
-        kref_get(&re->refcnt);
+        re->refcnt++;
 
         spin_unlock(&fs_info->reada_lock);