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Subject[PATCH 1/2] fs/xfs: Drop unnecessary NULL test
From: Julia Lawall <julia@diku.dk>

The result of container_of should not be NULL. In particular, in this case
the argument to the enclosing function has passed though INIT_DELAYED_WORK,
which dereferences it, implying that its container cannot be NULL.

The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
expression x,e;
@@
x = container_of(...)
... when != x = e
* x == NULL
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>

---
fs/xfs/xfs_mru_cache.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/fs/xfs/xfs_mru_cache.c b/fs/xfs/xfs_mru_cache.c
index 4b0613d..0651ce7 100644
--- a/fs/xfs/xfs_mru_cache.c
+++ b/fs/xfs/xfs_mru_cache.c
@@ -280,8 +280,8 @@ _xfs_mru_cache_reap(
xfs_mru_cache_t *mru = container_of(work, xfs_mru_cache_t, work.work);
unsigned long now, next;

- ASSERT(mru && mru->lists);
- if (!mru || !mru->lists)
+ ASSERT(mru->lists);
+ if (!mru->lists)
return;

spin_lock(&mru->lock);

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