From: Dong Aisheng <aisheng.dong@nxp.com>
To: linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Cc: dongas86@gmail.com, kernel@pengutronix.de, shawnguo@kernel.org,
linux-imx@nxp.com, linux-kernel@vger.kernel.org,
myungjoo.ham@samsung.com, kyungmin.park@samsung.com,
cw00.choi@samsung.com, abel.vesa@nxp.com,
Dong Aisheng <aisheng.dong@nxp.com>
Subject: [PATCH 09/11] PM / devfreq: governor: optimize simpleondemand get_target_freq
Date: Tue, 9 Mar 2021 20:58:51 +0800 [thread overview]
Message-ID: <1615294733-22761-22-git-send-email-aisheng.dong@nxp.com> (raw)
In-Reply-To: <1615294733-22761-1-git-send-email-aisheng.dong@nxp.com>
devfreq_simple_ondemand_data only needs to be initialized once when
calling devm_devfreq_add_device. It's unnecessary to put the data
check logic in the hot path (.get_target_freq()) where it will be
called all the time during polling. Instead, we only check and initialize
it one time during DEVFREQ_GOV_START.
This also helps check data validability in advance during DEVFREQ_GOV_START
rather than checking it later when running .get_target_freq().
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
---
drivers/devfreq/governor_simpleondemand.c | 50 +++++++++++++++--------
1 file changed, 34 insertions(+), 16 deletions(-)
diff --git a/drivers/devfreq/governor_simpleondemand.c b/drivers/devfreq/governor_simpleondemand.c
index ea287b57cbf3..341eb7e9dc04 100644
--- a/drivers/devfreq/governor_simpleondemand.c
+++ b/drivers/devfreq/governor_simpleondemand.c
@@ -15,15 +15,19 @@
/* Default constants for DevFreq-Simple-Ondemand (DFSO) */
#define DFSO_UPTHRESHOLD (90)
#define DFSO_DOWNDIFFERENCTIAL (5)
+
+static struct devfreq_simple_ondemand_data od_default = {
+ .upthreshold = DFSO_UPTHRESHOLD,
+ .downdifferential = DFSO_DOWNDIFFERENCTIAL,
+};
+
static int devfreq_simple_ondemand_func(struct devfreq *df,
unsigned long *freq)
{
int err;
struct devfreq_dev_status *stat;
unsigned long long a, b;
- unsigned int dfso_upthreshold = DFSO_UPTHRESHOLD;
- unsigned int dfso_downdifferential = DFSO_DOWNDIFFERENCTIAL;
- struct devfreq_simple_ondemand_data *data = df->data;
+ struct devfreq_simple_ondemand_data *od = df->data;
err = devfreq_update_stats(df);
if (err)
@@ -31,16 +35,6 @@ static int devfreq_simple_ondemand_func(struct devfreq *df,
stat = &df->last_status;
- if (data) {
- if (data->upthreshold)
- dfso_upthreshold = data->upthreshold;
- if (data->downdifferential)
- dfso_downdifferential = data->downdifferential;
- }
- if (dfso_upthreshold > 100 ||
- dfso_upthreshold < dfso_downdifferential)
- return -EINVAL;
-
/* Assume MAX if it is going to be divided by zero */
if (stat->total_time == 0) {
*freq = DEVFREQ_MAX_FREQ;
@@ -55,7 +49,7 @@ static int devfreq_simple_ondemand_func(struct devfreq *df,
/* Set MAX if it's busy enough */
if (stat->busy_time * 100 >
- stat->total_time * dfso_upthreshold) {
+ stat->total_time * od->upthreshold) {
*freq = DEVFREQ_MAX_FREQ;
return 0;
}
@@ -68,7 +62,7 @@ static int devfreq_simple_ondemand_func(struct devfreq *df,
/* Keep the current frequency */
if (stat->busy_time * 100 >
- stat->total_time * (dfso_upthreshold - dfso_downdifferential)) {
+ stat->total_time * (od->upthreshold - od->downdifferential)) {
*freq = stat->current_frequency;
return 0;
}
@@ -78,17 +72,41 @@ static int devfreq_simple_ondemand_func(struct devfreq *df,
a *= stat->current_frequency;
b = div_u64(a, stat->total_time);
b *= 100;
- b = div_u64(b, (dfso_upthreshold - dfso_downdifferential / 2));
+ b = div_u64(b, (od->upthreshold - od->downdifferential / 2));
*freq = (unsigned long) b;
return 0;
}
+static int devfreq_simple_ondemand_check_od(struct devfreq *devfreq)
+{
+ struct devfreq_simple_ondemand_data *od = devfreq->data;
+
+ if (od) {
+ if (!od->upthreshold)
+ od->upthreshold = DFSO_UPTHRESHOLD;
+
+ if (!od->downdifferential)
+ od->downdifferential = DFSO_DOWNDIFFERENCTIAL;
+
+ if (od->upthreshold > 100 ||
+ od->upthreshold < od->downdifferential)
+ return -EINVAL;
+ } else {
+ od = &od_default;
+ }
+
+ return 0;
+}
+
static int devfreq_simple_ondemand_handler(struct devfreq *devfreq,
unsigned int event, void *data)
{
switch (event) {
case DEVFREQ_GOV_START:
+ if (devfreq_simple_ondemand_check_od(devfreq))
+ return -EINVAL;
+
return devfreq_monitor_start(devfreq);
case DEVFREQ_GOV_STOP:
--
2.25.1
next prev parent reply other threads:[~2021-03-09 13:13 UTC|newest]
Thread overview: 58+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-09 12:58 [PATCH 00/11] PM / devfreq: a few small fixes and improvements Dong Aisheng
2021-03-09 12:58 ` [PATCH 01/11] doc: ABI: devfreq: remove invalid central_polling description Dong Aisheng
2021-03-09 15:01 ` Chanwoo Choi
2021-03-09 12:58 ` [PATCH 02/11] PM / devfreq: remove the invalid description for get_target_freq Dong Aisheng
2021-03-09 15:02 ` Chanwoo Choi
2021-03-09 15:14 ` Dong Aisheng
2021-03-09 12:58 ` [PATCH 03/11] PM / devfreq: fix the wrong set_freq path for userspace governor Dong Aisheng
2021-03-09 15:13 ` Chanwoo Choi
2021-03-09 15:16 ` Dong Aisheng
2021-03-09 12:58 ` [PATCH 04/11] PM / devfreq: bail out early if no freq changes in devfreq_set_target Dong Aisheng
2021-03-09 15:47 ` Chanwoo Choi
2021-03-10 2:42 ` Dong Aisheng
2021-03-09 12:58 ` [PATCH 05/11] PM / devfreq: use more accurate returned new_freq as resume_freq Dong Aisheng
2021-03-09 15:53 ` Chanwoo Choi
2021-03-10 2:43 ` Dong Aisheng
2021-03-10 3:07 ` Chanwoo Choi
2021-03-10 3:04 ` Dong Aisheng
2021-03-09 12:58 ` [PATCH 06/11] PM / devfreq: drop the unnecessary low variable initialization Dong Aisheng
2021-03-09 12:58 ` [PATCH 07/11] PM / devfreq: check get_dev_status before start monitor Dong Aisheng
2021-03-09 15:58 ` Chanwoo Choi
2021-03-09 16:12 ` Chanwoo Choi
2021-03-10 2:56 ` Dong Aisheng
2021-03-10 3:25 ` Chanwoo Choi
2021-03-10 4:56 ` Dong Aisheng
2021-03-11 7:10 ` Chanwoo Choi
2021-03-12 10:57 ` Dong Aisheng
2021-03-12 16:09 ` Chanwoo Choi
2021-03-13 6:45 ` Dong Aisheng
2021-03-18 8:03 ` Dong Aisheng
2021-03-18 9:54 ` Chanwoo Choi
2021-03-18 9:59 ` Chanwoo Choi
2021-03-18 10:51 ` Dong Aisheng
2021-03-10 2:51 ` Dong Aisheng
2021-03-09 12:58 ` [PATCH 08/11] PM / devfreq: check get_dev_status in devfreq_update_stats Dong Aisheng
2021-03-09 16:02 ` Chanwoo Choi
2021-03-09 16:20 ` Chanwoo Choi
2021-03-10 3:00 ` Dong Aisheng
2021-03-11 7:01 ` Chanwoo Choi
2021-03-09 12:58 ` [PATCH 09/11] PM / devfreq: governor: optimize simpleondemand get_target_freq Dong Aisheng
2021-03-09 16:09 ` Chanwoo Choi
2021-03-10 3:02 ` Dong Aisheng
2021-03-09 12:58 ` [PATCH 10/11] PM / devfreq: imx8m-ddrc: remove imx8m_ddrc_get_dev_status Dong Aisheng
2021-03-09 16:22 ` Chanwoo Choi
2021-03-09 12:58 ` [PATCH 11/11] PM / devfreq: imx8m-ddrc: drop polling_ms Dong Aisheng
2021-03-09 16:23 ` Chanwoo Choi
2021-03-10 3:03 ` Dong Aisheng
2021-03-09 12:58 ` [PATCH 00/11] PM / devfreq: a few small fixes and improvements Dong Aisheng
2021-03-09 12:58 ` [PATCH 01/11] doc: ABI: devfreq: remove invalid central_polling description Dong Aisheng
2021-03-09 12:58 ` [PATCH 02/11] PM / devfreq: remove the invalid description for get_target_freq Dong Aisheng
2021-03-09 12:58 ` [PATCH 03/11] PM / devfreq: fix the wrong set_freq path for userspace governor Dong Aisheng
2021-03-09 12:58 ` [PATCH 04/11] PM / devfreq: bail out early if no freq changes in devfreq_set_target Dong Aisheng
2021-03-09 12:58 ` [PATCH 05/11] PM / devfreq: use more accurate returned new_freq as resume_freq Dong Aisheng
2021-03-09 12:58 ` [PATCH 06/11] PM / devfreq: drop the unnecessary low variable initialization Dong Aisheng
2021-03-09 12:58 ` [PATCH 07/11] PM / devfreq: check get_dev_status before start monitor Dong Aisheng
2021-03-09 12:58 ` [PATCH 08/11] PM / devfreq: check get_dev_status in devfreq_update_stats Dong Aisheng
2021-03-09 12:58 ` Dong Aisheng [this message]
2021-03-09 12:58 ` [PATCH 10/11] PM / devfreq: imx8m-ddrc: remove imx8m_ddrc_get_dev_status Dong Aisheng
2021-03-09 12:58 ` [PATCH 11/11] PM / devfreq: imx8m-ddrc: drop polling_ms Dong Aisheng
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