+ drivers-cpuidle-move-dereference-after-null-test.patch added to -mm tree

+ drivers-cpuidle-move-dereference-after-null-test.patch added to -mm tree

[akpm]

The patch titled
     drivers/cpuidle: Move dereference after NULL test
has been added to the -mm tree.  Its filename is
     drivers-cpuidle-move-dereference-after-null-test.patch

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------------------------------------------------------
Subject: drivers/cpuidle: Move dereference after NULL test
From: Julia Lawall <julia@diku.dk>

It does not seem possible that ldev can be NULL, so drop the unnecessary
test.  If ldev can somehow be NULL, then the initialization of last_idx
should be moved below the test.

A simplified version of the semantic match that detects this problem is as
follows (http://coccinelle.lip6.fr/):

// <smpl>
@match exists@
expression x, E;
identifier fld;
@@

* x->fld
  ... when != \(x = E\|&x\)
* x == NULL
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/cpuidle/governors/ladder.c |    3 ---
 1 file changed, 3 deletions(-)

diff -puN drivers/cpuidle/governors/ladder.c~drivers-cpuidle-move-dereference-after-null-test drivers/cpuidle/governors/ladder.c
--- a/drivers/cpuidle/governors/ladder.c~drivers-cpuidle-move-dereference-after-null-test
+++ a/drivers/cpuidle/governors/ladder.c
@@ -69,9 +69,6 @@ static int ladder_select_state(struct cp
 	int last_residency, last_idx = ldev->last_state_idx;
 	int latency_req = pm_qos_requirement(PM_QOS_CPU_DMA_LATENCY);
 
-	if (unlikely(!ldev))
-		return 0;