cpuidle accounts the idle time for the C-state it was trying to enter and not to the actual state that the driver eventually entered. The driver may select a different state than the one chosen by cpuidle due to constraints like bus-mastering, etc. Change the time acounting code to look at the dev->last_state after returning from target_state->enter(). Driver can modify dev->last_state internally, inside the enter routine to reflect the actual C-state entered. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@xxxxxxxxx> --- drivers/cpuidle/cpuidle.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) Index: tip/drivers/cpuidle/cpuidle.c =================================================================== --- tip.orig/drivers/cpuidle/cpuidle.c 2008-09-23 13:52:59.000000000 -0700 +++ tip/drivers/cpuidle/cpuidle.c 2008-09-23 14:22:43.000000000 -0700 @@ -71,8 +71,11 @@ static void cpuidle_idle_call(void) target_state = &dev->states[next_state]; /* enter the state and update stats */ - dev->last_residency = target_state->enter(dev, target_state); dev->last_state = target_state; + dev->last_residency = target_state->enter(dev, target_state); + if (dev->last_state) + target_state = dev->last_state; + target_state->time += (unsigned long long)dev->last_residency; target_state->usage++; -- _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
