From: Rafael J. Wysocki <[email protected]>
Both trip_point_temp_store() and trip_point_hyst_store() use
thermal_zone_set_trip() to update a given trip point, but none of them
actually needs to change more than one field in struct thermal_trip
representing it. However, each of them effectively calls
__thermal_zone_get_trip() twice in a row for the same trip index value,
once directly and once via thermal_zone_set_trip(), which is not
particularly efficient, and the way in which thermal_zone_set_trip()
carries out the update is not particularly straightforward.
Moreover, some checks done by them both need not go under the thermal
zone lock and code duplication between them can be reduced quite a bit
by moving the majority of logic into thermal_zone_set_trip().
Rework all of the above functions to address the above.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <[email protected]>
---
v1 -> v2:
* Fix 2 typos in the changelog (Lukasz).
* Split one change into the [1/2].
---
drivers/thermal/thermal_core.h | 9 ++++++
drivers/thermal/thermal_sysfs.c | 52 ++++++++--------------------------
drivers/thermal/thermal_trip.c | 60 +++++++++++++++++++++++++++-------------
include/linux/thermal.h | 3 --
4 files changed, 62 insertions(+), 62 deletions(-)
Index: linux-pm/drivers/thermal/thermal_core.h
===================================================================
--- linux-pm.orig/drivers/thermal/thermal_core.h
+++ linux-pm/drivers/thermal/thermal_core.h
@@ -122,6 +122,15 @@ void __thermal_zone_device_update(struct
void __thermal_zone_set_trips(struct thermal_zone_device *tz);
int __thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
struct thermal_trip *trip);
+
+enum thermal_set_trip_target {
+ THERMAL_TRIP_SET_TEMP,
+ THERMAL_TRIP_SET_HYST,
+};
+
+int thermal_zone_set_trip(struct thermal_zone_device *tz, int trip_id,
+ enum thermal_set_trip_target what, const char *buf);
+
int thermal_zone_trip_id(struct thermal_zone_device *tz,
const struct thermal_trip *trip);
int __thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp);
Index: linux-pm/drivers/thermal/thermal_sysfs.c
===================================================================
--- linux-pm.orig/drivers/thermal/thermal_sysfs.c
+++ linux-pm/drivers/thermal/thermal_sysfs.c
@@ -120,31 +120,17 @@ trip_point_temp_store(struct device *dev
const char *buf, size_t count)
{
struct thermal_zone_device *tz = to_thermal_zone(dev);
- struct thermal_trip trip;
- int trip_id, ret;
+ int trip_id;
+ int ret;
+
+ if (!device_is_registered(dev))
+ return -ENODEV;
if (sscanf(attr->attr.name, "trip_point_%d_temp", &trip_id) != 1)
return -EINVAL;
- mutex_lock(&tz->lock);
-
- if (!device_is_registered(dev)) {
- ret = -ENODEV;
- goto unlock;
- }
-
- ret = __thermal_zone_get_trip(tz, trip_id, &trip);
- if (ret)
- goto unlock;
-
- ret = kstrtoint(buf, 10, &trip.temperature);
- if (ret)
- goto unlock;
+ ret = thermal_zone_set_trip(tz, trip_id, THERMAL_TRIP_SET_TEMP, buf);
- ret = thermal_zone_set_trip(tz, trip_id, &trip);
-unlock:
- mutex_unlock(&tz->lock);
-
return ret ? ret : count;
}
@@ -179,30 +165,16 @@ trip_point_hyst_store(struct device *dev
const char *buf, size_t count)
{
struct thermal_zone_device *tz = to_thermal_zone(dev);
- struct thermal_trip trip;
- int trip_id, ret;
+ int trip_id;
+ int ret;
+
+ if (!device_is_registered(dev))
+ return -ENODEV;
if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip_id) != 1)
return -EINVAL;
- mutex_lock(&tz->lock);
-
- if (!device_is_registered(dev)) {
- ret = -ENODEV;
- goto unlock;
- }
-
- ret = __thermal_zone_get_trip(tz, trip_id, &trip);
- if (ret)
- goto unlock;
-
- ret = kstrtoint(buf, 10, &trip.hysteresis);
- if (ret)
- goto unlock;
-
- ret = thermal_zone_set_trip(tz, trip_id, &trip);
-unlock:
- mutex_unlock(&tz->lock);
+ ret = thermal_zone_set_trip(tz, trip_id, THERMAL_TRIP_SET_HYST, buf);
return ret ? ret : count;
}
Index: linux-pm/drivers/thermal/thermal_trip.c
===================================================================
--- linux-pm.orig/drivers/thermal/thermal_trip.c
+++ linux-pm/drivers/thermal/thermal_trip.c
@@ -148,39 +148,61 @@ int thermal_zone_get_trip(struct thermal
EXPORT_SYMBOL_GPL(thermal_zone_get_trip);
int thermal_zone_set_trip(struct thermal_zone_device *tz, int trip_id,
- const struct thermal_trip *trip)
+ enum thermal_set_trip_target what, const char *buf)
{
- struct thermal_trip t;
- int ret;
+ struct thermal_trip *trip;
+ int val, ret = 0;
- ret = __thermal_zone_get_trip(tz, trip_id, &t);
+ if (trip_id < 0 || trip_id >= tz->num_trips)
+ ret = -EINVAL;
+
+ ret = kstrtoint(buf, 10, &val);
if (ret)
return ret;
- if (t.type != trip->type)
- return -EINVAL;
+ mutex_lock(&tz->lock);
- if (t.temperature != trip->temperature && tz->ops->set_trip_temp) {
- ret = tz->ops->set_trip_temp(tz, trip_id, trip->temperature);
- if (ret)
- return ret;
- }
+ trip = &tz->trips[trip_id];
- if (t.hysteresis != trip->hysteresis && tz->ops->set_trip_hyst) {
- ret = tz->ops->set_trip_hyst(tz, trip_id, trip->hysteresis);
- if (ret)
- return ret;
+ switch (what) {
+ case THERMAL_TRIP_SET_TEMP:
+ if (val == trip->temperature)
+ goto unlock;
+
+ if (tz->ops->set_trip_temp) {
+ ret = tz->ops->set_trip_temp(tz, trip_id, val);
+ if (ret)
+ goto unlock;
+ }
+ trip->temperature = val;
+ break;
+
+ case THERMAL_TRIP_SET_HYST:
+ if (val == trip->hysteresis)
+ goto unlock;
+
+ if (tz->ops->set_trip_hyst) {
+ ret = tz->ops->set_trip_hyst(tz, trip_id, val);
+ if (ret)
+ goto unlock;
+ }
+ trip->hysteresis = val;
+ break;
+
+ default:
+ ret = -EINVAL;
+ goto unlock;
}
- if (tz->trips && (t.temperature != trip->temperature || t.hysteresis != trip->hysteresis))
- tz->trips[trip_id] = *trip;
-
thermal_notify_tz_trip_change(tz->id, trip_id, trip->type,
trip->temperature, trip->hysteresis);
__thermal_zone_device_update(tz, THERMAL_TRIP_CHANGED);
- return 0;
+unlock:
+ mutex_unlock(&tz->lock);
+
+ return ret;
}
int thermal_zone_trip_id(struct thermal_zone_device *tz,
Index: linux-pm/include/linux/thermal.h
===================================================================
--- linux-pm.orig/include/linux/thermal.h
+++ linux-pm/include/linux/thermal.h
@@ -283,9 +283,6 @@ int __thermal_zone_get_trip(struct therm
int thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
struct thermal_trip *trip);
-int thermal_zone_set_trip(struct thermal_zone_device *tz, int trip_id,
- const struct thermal_trip *trip);
-
int for_each_thermal_trip(struct thermal_zone_device *tz,
int (*cb)(struct thermal_trip *, void *),
void *data);
On 11/28/23 13:58, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <[email protected]>
>
> Both trip_point_temp_store() and trip_point_hyst_store() use
> thermal_zone_set_trip() to update a given trip point, but none of them
> actually needs to change more than one field in struct thermal_trip
> representing it. However, each of them effectively calls
> __thermal_zone_get_trip() twice in a row for the same trip index value,
> once directly and once via thermal_zone_set_trip(), which is not
> particularly efficient, and the way in which thermal_zone_set_trip()
> carries out the update is not particularly straightforward.
>
> Moreover, some checks done by them both need not go under the thermal
> zone lock and code duplication between them can be reduced quite a bit
> by moving the majority of logic into thermal_zone_set_trip().
>
> Rework all of the above functions to address the above.
>
> No intentional functional impact.
>
> Signed-off-by: Rafael J. Wysocki <[email protected]>
> ---
>
> v1 -> v2:
> * Fix 2 typos in the changelog (Lukasz).
> * Split one change into the [1/2].
>
> ---
> drivers/thermal/thermal_core.h | 9 ++++++
> drivers/thermal/thermal_sysfs.c | 52 ++++++++--------------------------
> drivers/thermal/thermal_trip.c | 60 +++++++++++++++++++++++++++-------------
> include/linux/thermal.h | 3 --
> 4 files changed, 62 insertions(+), 62 deletions(-)
>
[snip]
> Index: linux-pm/drivers/thermal/thermal_trip.c
> ===================================================================
> --- linux-pm.orig/drivers/thermal/thermal_trip.c
> +++ linux-pm/drivers/thermal/thermal_trip.c
> @@ -148,39 +148,61 @@ int thermal_zone_get_trip(struct thermal
> EXPORT_SYMBOL_GPL(thermal_zone_get_trip);
>
> int thermal_zone_set_trip(struct thermal_zone_device *tz, int trip_id,
> - const struct thermal_trip *trip)
> + enum thermal_set_trip_target what, const char *buf)
> {
> - struct thermal_trip t;
> - int ret;
> + struct thermal_trip *trip;
> + int val, ret = 0;
>
> - ret = __thermal_zone_get_trip(tz, trip_id, &t);
> + if (trip_id < 0 || trip_id >= tz->num_trips)
> + ret = -EINVAL;
That shouldn't progress forward IMO, but simply 'return -EINVAL;'...
> +
> + ret = kstrtoint(buf, 10, &val);
> if (ret)
> return ret;
>
> - if (t.type != trip->type)
> - return -EINVAL;
> + mutex_lock(&tz->lock);
>
> - if (t.temperature != trip->temperature && tz->ops->set_trip_temp) {
> - ret = tz->ops->set_trip_temp(tz, trip_id, trip->temperature);
> - if (ret)
> - return ret;
> - }
> + trip = &tz->trips[trip_id];
... because here we might get an issue.
On Tue, Nov 28, 2023 at 10:42 PM Lukasz Luba <[email protected]> wrote:
>
>
>
> On 11/28/23 13:58, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <[email protected]>
> >
> > Both trip_point_temp_store() and trip_point_hyst_store() use
> > thermal_zone_set_trip() to update a given trip point, but none of them
> > actually needs to change more than one field in struct thermal_trip
> > representing it. However, each of them effectively calls
> > __thermal_zone_get_trip() twice in a row for the same trip index value,
> > once directly and once via thermal_zone_set_trip(), which is not
> > particularly efficient, and the way in which thermal_zone_set_trip()
> > carries out the update is not particularly straightforward.
> >
> > Moreover, some checks done by them both need not go under the thermal
> > zone lock and code duplication between them can be reduced quite a bit
> > by moving the majority of logic into thermal_zone_set_trip().
> >
> > Rework all of the above functions to address the above.
> >
> > No intentional functional impact.
> >
> > Signed-off-by: Rafael J. Wysocki <[email protected]>
> > ---
> >
> > v1 -> v2:
> > * Fix 2 typos in the changelog (Lukasz).
> > * Split one change into the [1/2].
> >
> > ---
> > drivers/thermal/thermal_core.h | 9 ++++++
> > drivers/thermal/thermal_sysfs.c | 52 ++++++++--------------------------
> > drivers/thermal/thermal_trip.c | 60 +++++++++++++++++++++++++++-------------
> > include/linux/thermal.h | 3 --
> > 4 files changed, 62 insertions(+), 62 deletions(-)
> >
>
> [snip]
>
> > Index: linux-pm/drivers/thermal/thermal_trip.c
> > ===================================================================
> > --- linux-pm.orig/drivers/thermal/thermal_trip.c
> > +++ linux-pm/drivers/thermal/thermal_trip.c
> > @@ -148,39 +148,61 @@ int thermal_zone_get_trip(struct thermal
> > EXPORT_SYMBOL_GPL(thermal_zone_get_trip);
> >
> > int thermal_zone_set_trip(struct thermal_zone_device *tz, int trip_id,
> > - const struct thermal_trip *trip)
> > + enum thermal_set_trip_target what, const char *buf)
> > {
> > - struct thermal_trip t;
> > - int ret;
> > + struct thermal_trip *trip;
> > + int val, ret = 0;
> >
> > - ret = __thermal_zone_get_trip(tz, trip_id, &t);
> > + if (trip_id < 0 || trip_id >= tz->num_trips)
> > + ret = -EINVAL;
>
> That shouldn't progress forward IMO, but simply 'return -EINVAL;'...
Good catch, thank you!
> > +
> > + ret = kstrtoint(buf, 10, &val);
> > if (ret)
> > return ret;
> >
> > - if (t.type != trip->type)
> > - return -EINVAL;
> > + mutex_lock(&tz->lock);
> >
> > - if (t.temperature != trip->temperature && tz->ops->set_trip_temp) {
> > - ret = tz->ops->set_trip_temp(tz, trip_id, trip->temperature);
> > - if (ret)
> > - return ret;
> > - }
> > + trip = &tz->trips[trip_id];
>
> ... because here we might get an issue.
Right.