[PATCH 11/25] hrtimer: Allow remote hrtimer enqueue with "expires_next" as expiry time

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From	Anna-Maria Gleixner <anna-maria@linutronix.de>
Newsgroups	linux.kernel
Subject	[PATCH 11/25] hrtimer: Allow remote hrtimer enqueue with "expires_next" as expiry time
Date	Thu, 31 Aug 2017 14:30:02 +0200
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When enqueuing a timer with expiry X into a timer queue, where already
a timer with expriy X is queued, the new timer is queued on the
right-hand side of the already queued timer.

Therefore it is no problem, to enqueue a hrtimer on a remote CPU with the
same expiry time than the programmed expiry time (expires_next) on this
CPU, because the reprogramming path is not executed - it is not the
"leftmost" hrtimer.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
---
 kernel/time/hrtimer.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -168,7 +168,7 @@ hrtimer_check_target(struct hrtimer *tim
 	ktime_t expires;
 
 	expires = ktime_sub(hrtimer_get_expires(timer), new_base->offset);
-	return expires <= new_base->cpu_base->expires_next;
+	return expires < new_base->cpu_base->expires_next;
 }
 
 #ifdef CONFIG_NO_HZ_COMMON

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[PATCH 11/25] hrtimer: Allow remote hrtimer enqueue with  "expires_next" as expiry time Anna-Maria Gleixner <anna-maria@linutronix.de> - 2017-08-31 14:30 +0200

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