From: Lukasz Luba <lukasz.luba@arm.com>
To: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org,
dri-devel@lists.freedesktop.org
Cc: amit.kucheria@verdurent.com, airlied@linux.ie,
daniel.lezcano@linaro.org, steven.price@arm.com,
alyssa.rosenzweig@collabora.com, rui.zhang@intel.com,
orjan.eide@arm.com, lukasz.luba@arm.com
Subject: [PATCH 2/5] thermal: devfreq_cooling: get a copy of device status
Date: Mon, 21 Sep 2020 13:20:04 +0100 [thread overview]
Message-ID: <20200921122007.29610-3-lukasz.luba@arm.com> (raw)
In-Reply-To: <20200921122007.29610-1-lukasz.luba@arm.com>
Devfreq cooling needs to now the correct status of the device in order
to operate. Do not rely on Devfreq last_status which might be a stale data
and get more up-to-date values of the load.
Devfreq framework can change the device status in the background. To
mitigate this situation make a copy of the status structure and use it
for internal calculations.
In addition this patch adds normalization function, which also makes sure
that whatever data comes from the device, it is in a sane range.
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
---
drivers/thermal/devfreq_cooling.c | 52 +++++++++++++++++++++++++------
1 file changed, 43 insertions(+), 9 deletions(-)
diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c
index 7063ccb7b86d..cf045bd4d16b 100644
--- a/drivers/thermal/devfreq_cooling.c
+++ b/drivers/thermal/devfreq_cooling.c
@@ -227,6 +227,24 @@ static inline unsigned long get_total_power(struct devfreq_cooling_device *dfc,
voltage);
}
+static void _normalize_load(struct devfreq_dev_status *status)
+{
+ /* Make some space if needed */
+ if (status->busy_time > 0xffff) {
+ status->busy_time >>= 10;
+ status->total_time >>= 10;
+ }
+
+ if (status->busy_time > status->total_time)
+ status->busy_time = status->total_time;
+
+ status->busy_time *= 100;
+ status->busy_time /= status->total_time ? : 1;
+
+ /* Avoid division by 0 */
+ status->busy_time = status->busy_time ? : 1;
+ status->total_time = 100;
+}
static int devfreq_cooling_get_requested_power(struct thermal_cooling_device *cdev,
struct thermal_zone_device *tz,
@@ -234,14 +252,22 @@ static int devfreq_cooling_get_requested_power(struct thermal_cooling_device *cd
{
struct devfreq_cooling_device *dfc = cdev->devdata;
struct devfreq *df = dfc->devfreq;
- struct devfreq_dev_status *status = &df->last_status;
+ struct devfreq_dev_status status;
unsigned long state;
- unsigned long freq = status->current_frequency;
+ unsigned long freq;
unsigned long voltage;
u32 dyn_power = 0;
u32 static_power = 0;
int res;
+ mutex_lock(&df->lock);
+ res = df->profile->get_dev_status(df->dev.parent, &status);
+ mutex_unlock(&df->lock);
+ if (res)
+ return res;
+
+ freq = status.current_frequency;
+
state = freq_get_state(dfc, freq);
if (state == THERMAL_CSTATE_INVALID) {
res = -EAGAIN;
@@ -269,16 +295,18 @@ static int devfreq_cooling_get_requested_power(struct thermal_cooling_device *cd
} else {
dyn_power = dfc->power_table[state];
+ _normalize_load(&status);
+
/* Scale dynamic power for utilization */
- dyn_power *= status->busy_time;
- dyn_power /= status->total_time;
+ dyn_power *= status.busy_time;
+ dyn_power /= status.total_time;
/* Get static power */
static_power = get_static_power(dfc, freq);
*power = dyn_power + static_power;
}
- trace_thermal_power_devfreq_get_power(cdev, status, freq, *power);
+ trace_thermal_power_devfreq_get_power(cdev, &status, freq, *power);
return 0;
fail:
@@ -312,14 +340,20 @@ static int devfreq_cooling_power2state(struct thermal_cooling_device *cdev,
{
struct devfreq_cooling_device *dfc = cdev->devdata;
struct devfreq *df = dfc->devfreq;
- struct devfreq_dev_status *status = &df->last_status;
- unsigned long freq = status->current_frequency;
+ struct devfreq_dev_status status;
unsigned long busy_time;
+ unsigned long freq;
s32 dyn_power;
u32 static_power;
s32 est_power;
int i;
+ mutex_lock(&df->lock);
+ status = df->last_status;
+ mutex_unlock(&df->lock);
+
+ freq = status.current_frequency;
+
if (dfc->power_ops->get_real_power) {
/* Scale for resource utilization */
est_power = power * dfc->res_util;
@@ -331,8 +365,8 @@ static int devfreq_cooling_power2state(struct thermal_cooling_device *cdev,
dyn_power = dyn_power > 0 ? dyn_power : 0;
/* Scale dynamic power for utilization */
- busy_time = status->busy_time ?: 1;
- est_power = (dyn_power * status->total_time) / busy_time;
+ busy_time = status.busy_time ?: 1;
+ est_power = (dyn_power * status.total_time) / busy_time;
}
/*
--
2.17.1
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
next prev parent reply other threads:[~2020-09-22 7:52 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-21 12:20 [PATCH 0/5] Thermal devfreq cooling improvements with Energy Model Lukasz Luba
2020-09-21 12:20 ` [PATCH 1/5] thermal: devfreq_cooling: change tracing function and arguments Lukasz Luba
2020-09-21 12:20 ` Lukasz Luba [this message]
2020-10-07 16:11 ` [PATCH 2/5] thermal: devfreq_cooling: get a copy of device status Ionela Voinescu
2020-10-22 10:55 ` Lukasz Luba
2020-12-01 10:36 ` Ionela Voinescu
2020-12-01 12:19 ` Lukasz Luba
2020-12-01 14:55 ` Ionela Voinescu
2020-10-14 14:34 ` Daniel Lezcano
2020-10-22 11:45 ` Lukasz Luba
2020-09-21 12:20 ` [PATCH 3/5] thermal: devfreq_cooling: add new registration functions with Energy Model Lukasz Luba
2020-10-07 12:07 ` Ionela Voinescu
2020-10-22 11:17 ` Lukasz Luba
2020-12-01 14:05 ` Ionela Voinescu
2020-12-01 14:37 ` Lukasz Luba
2020-12-01 15:02 ` Ionela Voinescu
2020-09-21 12:20 ` [PATCH 4/5] thermal: devfreq_cooling: remove old power model and use EM Lukasz Luba
2020-10-07 15:12 ` Ionela Voinescu
2020-10-22 11:26 ` Lukasz Luba
2020-09-21 12:20 ` [PATCH 5/5] drm/panfrost: Register devfreq cooling and attempt to add Energy Model Lukasz Luba
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200921122007.29610-3-lukasz.luba@arm.com \
--to=lukasz.luba@arm.com \
--cc=airlied@linux.ie \
--cc=alyssa.rosenzweig@collabora.com \
--cc=amit.kucheria@verdurent.com \
--cc=daniel.lezcano@linaro.org \
--cc=dri-devel@lists.freedesktop.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=orjan.eide@arm.com \
--cc=rui.zhang@intel.com \
--cc=steven.price@arm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).