Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
thermal: core: Suspend thermal zones later and resume them earlier
To avoid some undesirable interactions between thermal zone suspend
and resume with user space that is running when those operations are
carried out, move them closer to the suspend and resume of devices,
respectively, by updating dpm_prepare() to carry out thermal zone
suspend and dpm_complete() to start thermal zone resume (that will
continue asynchronously).
This also makes the code easier to follow by removing one, arguably
redundant, level of indirection represented by the thermal PM notifier.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Armin Wolf <W_Armin@gmx.de>
Link: https://patch.msgid.link/2036875.PYKUYFuaPT@rafael.j.wysocki
+29
-42
+5
drivers/base/power/main.c
+5
drivers/base/power/main.c
···
33
33
#include <trace/events/power.h>
34
34
#include <linux/cpufreq.h>
35
35
#include <linux/devfreq.h>
36
+
#include <linux/thermal.h>
36
37
#include <linux/timer.h>
37
38
#include <linux/nmi.h>
38
39
···
1283
1282
list_splice(&list, &dpm_list);
1284
1283
mutex_unlock(&dpm_list_mtx);
1285
1284
1285
+
/* Start resuming thermal control */
1286
+
thermal_pm_complete();
1286
1287
/* Allow device probing and trigger re-probing of deferred devices */
1287
1288
device_unblock_probing();
1288
1289
trace_suspend_resume(TPS("dpm_complete"), state.event, false);
···
2228
2225
* instead. The normal behavior will be restored in dpm_complete().
2229
2226
*/
2230
2227
device_block_probing();
2228
+
/* Suspend thermal control. */
2229
+
thermal_pm_prepare();
2231
2230
2232
2231
mutex_lock(&dpm_list_mtx);
2233
2232
while (!list_empty(&dpm_list) && !error) {
+18
-42
drivers/thermal/thermal_core.c
+18
-42
drivers/thermal/thermal_core.c
···
1823
1823
cancel_delayed_work(&tz->poll_queue);
1824
1824
}
1825
1825
1826
-
static void thermal_pm_notify_prepare(void)
1826
+
static void __thermal_pm_prepare(void)
1827
1827
{
1828
1828
struct thermal_zone_device *tz;
1829
1829
···
1833
1833
1834
1834
list_for_each_entry(tz, &thermal_tz_list, node)
1835
1835
thermal_zone_pm_prepare(tz);
1836
+
}
1837
+
1838
+
void thermal_pm_prepare(void)
1839
+
{
1840
+
if (thermal_class_unavailable)
1841
+
return;
1842
+
1843
+
__thermal_pm_prepare();
1844
+
/*
1845
+
* Allow any leftover thermal work items already on the worqueue to
1846
+
* complete so they don't get in the way later.
1847
+
*/
1848
+
flush_workqueue(thermal_wq);
1836
1849
}
1837
1850
1838
1851
static void thermal_zone_pm_complete(struct thermal_zone_device *tz)
···
1864
1851
mod_delayed_work(thermal_wq, &tz->poll_queue, 0);
1865
1852
}
1866
1853
1867
-
static void thermal_pm_notify_complete(void)
1854
+
void thermal_pm_complete(void)
1868
1855
{
1869
1856
struct thermal_zone_device *tz;
1857
+
1858
+
if (thermal_class_unavailable)
1859
+
return;
1870
1860
1871
1861
guard(mutex)(&thermal_list_lock);
1872
1862
···
1878
1862
list_for_each_entry(tz, &thermal_tz_list, node)
1879
1863
thermal_zone_pm_complete(tz);
1880
1864
}
1881
-
1882
-
static int thermal_pm_notify(struct notifier_block *nb,
1883
-
unsigned long mode, void *_unused)
1884
-
{
1885
-
switch (mode) {
1886
-
case PM_HIBERNATION_PREPARE:
1887
-
case PM_RESTORE_PREPARE:
1888
-
case PM_SUSPEND_PREPARE:
1889
-
thermal_pm_notify_prepare();
1890
-
/*
1891
-
* Allow any leftover thermal work items already on the
1892
-
* worqueue to complete so they don't get in the way later.
1893
-
*/
1894
-
flush_workqueue(thermal_wq);
1895
-
break;
1896
-
case PM_POST_HIBERNATION:
1897
-
case PM_POST_RESTORE:
1898
-
case PM_POST_SUSPEND:
1899
-
thermal_pm_notify_complete();
1900
-
break;
1901
-
default:
1902
-
break;
1903
-
}
1904
-
return 0;
1905
-
}
1906
-
1907
-
static struct notifier_block thermal_pm_nb = {
1908
-
.notifier_call = thermal_pm_notify,
1909
-
/*
1910
-
* Run at the lowest priority to avoid interference between the thermal
1911
-
* zone resume work items spawned by thermal_pm_notify() and the other
1912
-
* PM notifiers.
1913
-
*/
1914
-
.priority = INT_MIN,
1915
-
};
1916
1865
1917
1866
static int __init thermal_init(void)
1918
1867
{
···
1904
1923
goto unregister_governors;
1905
1924
1906
1925
thermal_class_unavailable = false;
1907
-
1908
-
result = register_pm_notifier(&thermal_pm_nb);
1909
-
if (result)
1910
-
pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1911
-
result);
1912
1926
1913
1927
return 0;
1914
1928
+6
include/linux/thermal.h
+6
include/linux/thermal.h
···
273
273
int thermal_zone_device_enable(struct thermal_zone_device *tz);
274
274
int thermal_zone_device_disable(struct thermal_zone_device *tz);
275
275
void thermal_zone_device_critical(struct thermal_zone_device *tz);
276
+
277
+
void thermal_pm_prepare(void);
278
+
void thermal_pm_complete(void);
276
279
#else
277
280
static inline struct thermal_zone_device *thermal_zone_device_register_with_trips(
278
281
const char *type,
···
353
350
354
351
static inline int thermal_zone_device_disable(struct thermal_zone_device *tz)
355
352
{ return -ENODEV; }
353
+
354
+
static inline void thermal_pm_prepare(void) {}
355
+
static inline void thermal_pm_complete(void) {}
356
356
#endif /* CONFIG_THERMAL */
357
357
358
358
#endif /* __THERMAL_H__ */