linux-kernel - [PATCH 1/4] cpuidle: teo: Ignore disabled idle states that are too deep

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Date:   Thu, 10 Oct 2019 23:32:17 +0200
From:   "Rafael J. Wysocki" <rjw@...ysocki.net>
To:     Linux PM <linux-pm@...r.kernel.org>
Cc:     LKML <linux-kernel@...r.kernel.org>,
        Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Daniel Lezcano <daniel.lezcano@...aro.org>,
        Doug Smythies <dsmythies@...us.net>
Subject: [PATCH 1/4] cpuidle: teo: Ignore disabled idle states that are too deep

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

Prevent disabled CPU idle state with target residencies beyond the
anticipated idle duration from being taken into account by the TEO
governor.

Fixes: b26bf6ab716f ("cpuidle: New timer events oriented governor for tickless systems")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
---
 drivers/cpuidle/governors/teo.c |    7 +++++++
 1 file changed, 7 insertions(+)

Index: linux-pm/drivers/cpuidle/governors/teo.c
===================================================================
--- linux-pm.orig/drivers/cpuidle/governors/teo.c
+++ linux-pm/drivers/cpuidle/governors/teo.c
@@ -258,6 +258,13 @@ static int teo_select(struct cpuidle_dri
 
 		if (s->disabled || su->disable) {
 			/*
+			 * Ignore disabled states with target residencies beyond
+			 * the anticipated idle duration.
+			 */
+			if (s->target_residency > duration_us)
+				continue;
+
+			/*
 			 * If the "early hits" metric of a disabled state is
 			 * greater than the current maximum, it should be taken
 			 * into account, because it would be a mistake to select