Merge branch 'linus' into x86/pat

[linux-2.6-omap-h63xx.git] / fs / xfs / xfs_mru_cache.c

diff --git a/fs/xfs/xfs_mru_cache.c b/fs/xfs/xfs_mru_cache.c
index 012209eda35d847a61b1f13b7c7caa579455956d..a0b2c0a2589a97166f23982999aa3a15b95a9687 100644 (file)
--- a/fs/xfs/xfs_mru_cache.c
+++ b/fs/xfs/xfs_mru_cache.c
@@ -225,10 +225,14 @@ _xfs_mru_cache_list_insert(
  * list need to be deleted.  For each element this involves removing it from the
  * data store, removing it from the reap list, calling the client's free
  * function and deleting the element from the element zone.
+ *
+ * We get called holding the mru->lock, which we drop and then reacquire.
+ * Sparse need special help with this to tell it we know what we are doing.
  */
 STATIC void
 _xfs_mru_cache_clear_reap_list(
-       xfs_mru_cache_t         *mru)
+       xfs_mru_cache_t         *mru) __releases(mru->lock) __acquires(mru->lock)
+
 {
        xfs_mru_cache_elem_t    *elem, *next;
        struct list_head        tmp;
@@ -528,6 +532,10 @@ xfs_mru_cache_delete(
  *
  * If the element isn't found, this function returns NULL and the spinlock is
  * released.  xfs_mru_cache_done() should NOT be called when this occurs.
+ *
+ * Because sparse isn't smart enough to know about conditional lock return
+ * status, we need to help it get it right by annotating the path that does
+ * not release the lock.
  */
 void *
 xfs_mru_cache_lookup(
@@ -545,8 +553,8 @@ xfs_mru_cache_lookup(
        if (elem) {
                list_del(&elem->list_node);
                _xfs_mru_cache_list_insert(mru, elem);
-       }
-       else
+               __release(mru_lock); /* help sparse not be stupid */
+       } else
                spin_unlock(&mru->lock);
 
        return elem ? elem->value : NULL;
@@ -575,6 +583,8 @@ xfs_mru_cache_peek(
        elem = radix_tree_lookup(&mru->store, key);
        if (!elem)
                spin_unlock(&mru->lock);
+       else
+               __release(mru_lock); /* help sparse not be stupid */
 
        return elem ? elem->value : NULL;
 }
@@ -586,7 +596,7 @@ xfs_mru_cache_peek(
  */
 void
 xfs_mru_cache_done(
-       xfs_mru_cache_t *mru)
+       xfs_mru_cache_t *mru) __releases(mru->lock)
 {
        spin_unlock(&mru->lock);
 }