[PATCH 1/6] cpuidle: Set polling in poll_idle
From: Andy Lutomirski
Date: Tue Jun 03 2014 - 20:31:40 EST
poll_idle is the archetypal polling idle loop; tell the core idle
code about it.
This avoids pointless IPIs when all of the other cpuidle states are
disabled.
Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
---
drivers/cpuidle/driver.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
index 136d6a2..9634f20 100644
--- a/drivers/cpuidle/driver.c
+++ b/drivers/cpuidle/driver.c
@@ -187,8 +187,11 @@ static int poll_idle(struct cpuidle_device *dev,
t1 = ktime_get();
local_irq_enable();
- while (!need_resched())
- cpu_relax();
+ if (!current_set_polling_and_test()) {
+ while (!need_resched())
+ cpu_relax();
+ }
+ current_clr_polling();
t2 = ktime_get();
diff = ktime_to_us(ktime_sub(t2, t1));
--
1.9.3
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/