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random: Use this_cpu_inc_return

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__this_cpu_inc can create a single instruction to do the same as
__get_cpu_var()++.

Cc: Richard Kennedy <richard@rsk.demon.co.uk>
Cc: Matt Mackall <mpm@selenic.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Christoph Lameter
2010-12-06 11:40:06 -06:00
committed by Tejun Heo
parent ee1be86263
commit b29c617af3
1 changed files with 1 additions and 1 deletions
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2
drivers/char/random.c
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@@ -626,7 +626,7 @@ static void add_timer_randomness(struct timer_rand_state *state, unsigned num)
preempt_disable(); preempt_disable();
/* if over the trickle threshold, use only 1 in 4096 samples */ /* if over the trickle threshold, use only 1 in 4096 samples */
if (input_pool.entropy_count > trickle_thresh && if (input_pool.entropy_count > trickle_thresh &&
(__get_cpu_var(trickle_count)++ & 0xfff)) ((__this_cpu_inc_return(trickle_count) - 1) & 0xfff))
goto out; goto out;
sample.jiffies = jiffies; sample.jiffies = jiffies;