linux-kernel - [PATCH 04/11] PM / devfreq: Remove redundant frequency adjustment from governors

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Date:   Fri, 25 May 2018 13:30:36 -0700
From:   Matthias Kaehlcke <mka@...omium.org>
To:     MyungJoo Ham <myungjoo.ham@...sung.com>
Cc:     Kyungmin Park <kyungmin.park@...sung.com>,
        Chanwoo Choi <cw00.choi@...sung.com>,
        Arnd Bergmann <arnd@...db.de>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Rob Herring <robh+dt@...nel.org>,
        Mark Rutland <mark.rutland@....com>, linux-pm@...r.kernel.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        Brian Norris <briannorris@...omium.org>,
        Douglas Anderson <dianders@...omium.org>,
        Matthias Kaehlcke <mka@...omium.org>
Subject: [PATCH 04/11] PM / devfreq: Remove redundant frequency adjustment from governors

The userspace and simpleondemand governor determine a target frequency and
then adjust it according to the df->min/max_freq limits that might have
been set by user space. This adjustment is redundant, it is done in
update_devfreq() for any governor, right after returning from
governor->get_target_freq().

Signed-off-by: Matthias Kaehlcke <mka@...omium.org>
---
 drivers/devfreq/governor_simpleondemand.c |  5 -----
 drivers/devfreq/governor_userspace.c      | 16 ++++------------
 2 files changed, 4 insertions(+), 17 deletions(-)

diff --git a/drivers/devfreq/governor_simpleondemand.c b/drivers/devfreq/governor_simpleondemand.c
index 278964783fa6..3da7554b4837 100644
--- a/drivers/devfreq/governor_simpleondemand.c
+++ b/drivers/devfreq/governor_simpleondemand.c
@@ -84,11 +84,6 @@ static int devfreq_simple_ondemand_func(struct devfreq *df,
 	b = div_u64(b, (dfso_upthreshold - dfso_downdifferential / 2));
 	*freq = (unsigned long) b;
 
-	if (df->min_freq && *freq < df->min_freq)
-		*freq = df->min_freq;
-	if (df->max_freq && *freq > df->max_freq)
-		*freq = df->max_freq;
-
 	return 0;
 }
 
diff --git a/drivers/devfreq/governor_userspace.c b/drivers/devfreq/governor_userspace.c
index 080607c3f34d..378d84c011df 100644
--- a/drivers/devfreq/governor_userspace.c
+++ b/drivers/devfreq/governor_userspace.c
@@ -26,19 +26,11 @@ static int devfreq_userspace_func(struct devfreq *df, unsigned long *freq)
 {
 	struct userspace_data *data = df->data;
 
-	if (data->valid) {
-		unsigned long adjusted_freq = data->user_frequency;
-
-		if (df->max_freq && adjusted_freq > df->max_freq)
-			adjusted_freq = df->max_freq;
-
-		if (df->min_freq && adjusted_freq < df->min_freq)
-			adjusted_freq = df->min_freq;
-
-		*freq = adjusted_freq;
-	} else {
+	if (data->valid)
+		*freq = data->user_frequency;
+	else
 		*freq = df->previous_freq; /* No user freq specified yet */
-	}
+
 	return 0;
 }
 
-- 
2.17.0.921.gf22659ad46-goog