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drivers/cpuidle: Move dereference after NULL test

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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>
Acked-by: 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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Julia Lawall 2009-12-14 18:00:09 -08:00 committed by Linus Torvalds
parent 471452104b
commit faa7b7ddca
1 changed files with 0 additions and 3 deletions
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3
drivers/cpuidle/governors/ladder.c
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@ -69,9 +69,6 @@ static int ladder_select_state(struct cpuidle_device *dev)
int last_residency, last_idx = ldev->last_state_idx; int last_residency, last_idx = ldev->last_state_idx;
int latency_req = pm_qos_requirement(PM_QOS_CPU_DMA_LATENCY); int latency_req = pm_qos_requirement(PM_QOS_CPU_DMA_LATENCY);
if (unlikely(!ldev))
return 0;
/* Special case when user has set very strict latency requirement */ /* Special case when user has set very strict latency requirement */
if (unlikely(latency_req == 0)) { if (unlikely(latency_req == 0)) {
ladder_do_selection(ldev, last_idx, 0); ladder_do_selection(ldev, last_idx, 0);