Commit-ID:  35b61edb41ffee58711850e76215b852386ddb10
Gitweb:     http://git.kernel.org/tip/35b61edb41ffee58711850e76215b852386ddb10
Author:     Thomas Gleixner <t...@linutronix.de>
AuthorDate: Wed, 6 Mar 2013 11:18:37 +0000
Committer:  Thomas Gleixner <t...@linutronix.de>
CommitDate: Wed, 13 Mar 2013 11:39:40 +0100

x86: Use tick broadcast expired check

Avoid going back into deep idle if the tick broadcast IPI is about to
fire.

Signed-off-by: Thomas Gleixner <t...@linutronix.de>
Cc: John Stultz <john.stu...@linaro.org>
Cc: Arjan van de Veen <ar...@infradead.org>
Cc: x...@kernel.org
Link: http://lkml.kernel.org/r/20130306111537.702278...@linutronix.de
---
 arch/x86/kernel/process.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 14ae100..aa524da 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -336,6 +336,18 @@ void cpu_idle(void)
                        local_touch_nmi();
                        local_irq_disable();
 
+                       /*
+                        * We detected in the wakeup path that the
+                        * tick broadcast device expired for us, but
+                        * we raced with the other CPU and came back
+                        * here before it was able to fire the IPI.
+                        * No point in going idle.
+                        */
+                       if (tick_check_broadcast_expired()) {
+                               local_irq_enable();
+                               continue;
+                       }
+
                        enter_idle();
 
                        /* Don't trace irqs off for idle */
--
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