linux-kernel - [PATCH 1/1] cpuidle/menu: avoid prioritizing physical state over polling state

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Message-Id: <20240809073120.250974-2-aboorvad@linux.ibm.com>
Date: Fri,  9 Aug 2024 13:01:20 +0530
From: Aboorva Devarajan <aboorvad@...ux.ibm.com>
To: rafael@...nel.org, daniel.lezcano@...aro.org, linux-pm@...r.kernel.org,
        linux-kernel@...r.kernel.org
Cc: aboorvad@...ux.ibm.com, christian.loehle@....com, gautam@...ux.ibm.com
Subject: [PATCH 1/1] cpuidle/menu: avoid prioritizing physical state over polling state

Update the cpuidle menu governor to avoid prioritizing physical states
over polling states when predicted idle duration is lesser than the
physical states target residency duration for performance gains.

Signed-off-by: Aboorva Devarajan <aboorvad@...ux.ibm.com>
---
 drivers/cpuidle/governors/menu.c | 11 -----------
 1 file changed, 11 deletions(-)

diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index f3c9d49f0f2a..cf99ca103f9b 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -354,17 +354,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
 			idx = i; /* first enabled state */
 
 		if (s->target_residency_ns > predicted_ns) {
-			/*
-			 * Use a physical idle state, not busy polling, unless
-			 * a timer is going to trigger soon enough.
-			 */
-			if ((drv->states[idx].flags & CPUIDLE_FLAG_POLLING) &&
-			    s->exit_latency_ns <= latency_req &&
-			    s->target_residency_ns <= data->next_timer_ns) {
-				predicted_ns = s->target_residency_ns;
-				idx = i;
-				break;
-			}
 			if (predicted_ns < TICK_NSEC)
 				break;
 
-- 
2.39.3