cpuidle: poll_state: Disregard disable idle states

commit 800fb34a99ce7d22dca839c90f869c7a12b50f70 upstream

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: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NYihao Wu <wuyihao@linux.alibaba.com>
Acked-by: NMichael Wang <yun.wang@linux.alibaba.com>

drivers/cpuidle/poll_state.c

@@ -20,8 +20,17 @@ static int __cpuidle poll_idle(struct cpuidle_device *dev,
 
 	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();