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From: Christian Loehle <christian.loehle@arm.com>
To: linux-pm@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	rafael@kernel.org
Cc: vincent.guittot@linaro.org,
	qyousef@layalina.io,
	peterz@infradead.org,
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	kajetan.puchalski@arm.com,
	lukasz.luba@arm.com,
	dietmar.eggemann@arm.com,
	Christian Loehle <christian.loehle@arm.com>
Subject: [PATCH 4/6] cpuidle: teo: Increase minimum time to stop tick
Date: Thu,  6 Jun 2024 10:00:48 +0100
Message-Id: <20240606090050.327614-5-christian.loehle@arm.com>
In-Reply-To: <20240606090050.327614-1-christian.loehle@arm.com>
References: <20240606090050.327614-1-christian.loehle@arm.com>
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Since stopping the tick isn't free, add at least some minor constant
(1ms) for the threshold to stop the tick.

Signed-off-by: Christian Loehle <christian.loehle@arm.com>
---
 drivers/cpuidle/governors/teo.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/cpuidle/governors/teo.c b/drivers/cpuidle/governors/teo.c
index 216d34747e3b..ca9422bbd8db 100644
--- a/drivers/cpuidle/governors/teo.c
+++ b/drivers/cpuidle/governors/teo.c
@@ -622,10 +622,10 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
 	/*
 	 * Allow the tick to be stopped unless the selected state is a polling
 	 * one or the expected idle duration is shorter than the tick period
-	 * length.
+	 * length plus some constant (1ms) to account for stopping it.
 	 */
 	if ((!(drv->states[idx].flags & CPUIDLE_FLAG_POLLING) &&
-	    duration_ns >= TICK_NSEC) || tick_nohz_tick_stopped())
+	    duration_ns > NSEC_PER_MSEC + TICK_NSEC) || tick_nohz_tick_stopped())
 		return idx;
 
 out_tick_state:
-- 
2.34.1