From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Linux PM <linux-pm@vger.kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
LKML <linux-kernel@vger.kernel.org>,
Daniel Lezcano <daniel.lezcano@linaro.org>
Subject: [PATCH 6/6] cpuidle: menu: Move the latency_req == 0 special case check
Date: Tue, 02 Oct 2018 23:47:43 +0200 [thread overview]
Message-ID: <9002841.GWJsep0FYb@aspire.rjw.lan> (raw)
In-Reply-To: <3510260.hvypppS8Bs@aspire.rjw.lan>
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
It is better to always update data->bucket before returning from
menu_select() so as to prevent disturbing the wakeup statistics
collected by the governor, so combine the latency_req == 0 special
check with the more general check below.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/cpuidle/governors/menu.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
Index: linux-pm/drivers/cpuidle/governors/menu.c
===================================================================
--- linux-pm.orig/drivers/cpuidle/governors/menu.c
+++ linux-pm/drivers/cpuidle/governors/menu.c
@@ -297,19 +297,13 @@ static int menu_select(struct cpuidle_dr
data->needs_update = 0;
}
- /* Special case when user has set very strict latency requirement */
- if (unlikely(latency_req == 0)) {
- *stop_tick = false;
- return 0;
- }
-
/* determine the expected residency time, round up */
data->next_timer_us = ktime_to_us(tick_nohz_get_sleep_length(&delta_next));
get_iowait_load(&nr_iowaiters, &cpu_load);
data->bucket = which_bucket(data->next_timer_us, nr_iowaiters);
- if (unlikely(drv->state_count <= 1) ||
+ if (unlikely(drv->state_count <= 1 || latency_req == 0) ||
((data->next_timer_us < drv->states[1].target_residency ||
latency_req < drv->states[1].exit_latency) &&
!drv->states[0].disabled && !dev->states_usage[0].disable)) {
next prev parent reply other threads:[~2018-10-02 21:51 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-02 21:41 [PATCH 0/6] cpuidle: menu: Fixes, optimizations and cleanups Rafael J. Wysocki
2018-10-02 21:42 ` [PATCH 1/6] cpuidle: menu: Fix wakeup statistics updates for polling state Rafael J. Wysocki
2018-10-04 8:19 ` Daniel Lezcano
2018-10-02 21:42 ` [PATCH 2/6] cpuidle: menu: Compute first_idx when latency_req is known Rafael J. Wysocki
2018-10-04 14:22 ` Daniel Lezcano
2018-10-02 21:44 ` [PATCH 3/6] cpuidle: menu: Get rid of first_idx from menu_select() Rafael J. Wysocki
2018-10-04 7:46 ` Peter Zijlstra
2018-10-04 7:53 ` Rafael J. Wysocki
2018-10-04 8:00 ` Peter Zijlstra
2018-10-04 14:51 ` Daniel Lezcano
2018-10-04 17:19 ` Rafael J. Wysocki
2018-10-05 8:35 ` Daniel Lezcano
2018-10-05 8:49 ` Rafael J. Wysocki
2018-10-02 21:45 ` [PATCH 4/6] cpuidle: menu: Do not update last_state_idx in menu_select() Rafael J. Wysocki
2018-10-04 14:57 ` Daniel Lezcano
2018-10-02 21:46 ` [PATCH 5/6] cpuidle: menu: Avoid computations for very close timers Rafael J. Wysocki
2018-10-04 15:50 ` Daniel Lezcano
2018-10-04 17:11 ` Rafael J. Wysocki
2018-10-02 21:47 ` Rafael J. Wysocki [this message]
2018-10-04 6:55 ` [PATCH 0/6] cpuidle: menu: Fixes, optimizations and cleanups Rafael J. Wysocki
2018-10-04 7:51 ` Peter Zijlstra
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