[PATCH] cpuidle: poll_state: Disregard disable idle states

From: Rafael J. Wysocki
Date: Mon Dec 03 2018 - 07:33:07 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

When computing the limit of time to spend in the loop in poll_idle(),
use the target residency of the first enabled idle state deeper than
state 0 instead of always using the target residency of state 1.

This helps when state 1 is disabled for diagnostics, for instance.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/cpuidle/poll_state.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)

Index: linux-pm/drivers/cpuidle/poll_state.c
===================================================================
--- linux-pm.orig/drivers/cpuidle/poll_state.c
+++ linux-pm/drivers/cpuidle/poll_state.c
@@ -20,8 +20,17 @@ static int __cpuidle poll_idle(struct cp

local_irq_enable();
if (!current_set_polling_and_test()) {
- u64 limit = (u64)drv->states[1].target_residency * NSEC_PER_USEC;
unsigned int loop_count = 0;
+ u64 limit = TICK_USEC;
+ int i;
+
+ for (i = 1; i < drv->state_count; i++) {
+ if (drv->states[i].disabled || dev->states_usage[i].disable)
+ continue;
+
+ limit = (u64)drv->states[i].target_residency * NSEC_PER_USEC;
+ break;
+ }

while (!need_resched()) {
cpu_relax();