Re: [PATCH 7/7] Cpuidle: poll state can measure residency

From: Daniel Lezcano
Date: Tue Feb 25 2014 - 05:57:07 EST


On 02/24/2014 07:29 AM, Tuukka Tikkanen wrote:
For some platforms, a poll state is inserted in the cpuidle driver states.
The flags for the state do not indicate that timekeeping is not affected.
As the state does not do anything apart from calling cpu_relax(), the
times returned by ktime_get should remain valid. Add the missing flag.

Yes, but it is done with the interrupt enabled, so the interrupt handler + softirq handler times will be accounted in the residency time.

I am not sure adding this flag is good.

Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@xxxxxxxxxx>
---
drivers/cpuidle/driver.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
index 06dbe7c..136d6a2 100644
--- a/drivers/cpuidle/driver.c
+++ b/drivers/cpuidle/driver.c
@@ -209,7 +209,7 @@ static void poll_idle_init(struct cpuidle_driver *drv)
state->exit_latency = 0;
state->target_residency = 0;
state->power_usage = -1;
- state->flags = 0;
+ state->flags = CPUIDLE_FLAG_TIME_VALID;
state->enter = poll_idle;
state->disabled = false;
}



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