Power management fixes for 5.12-rc6

- Fix race condition related to the handling of supplier devices
    during consumer device probe and fix the order of decrementation
    of two related reference counters in the runtime PM core code
    handling supplier devices (Adrian Hunter).
 
  - Fix kerneldoc comments in cpufreq that have not been updated along
    with the functions documented by them (Geert Uytterhoeven).
 -----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAmBnNicSHHJqd0Byand5
 c29ja2kubmV0AAoJEILEb/54YlRxwocQAKBHmmBute8vqdaVL72TBc+FtoULeFdf
 V5eXAiLIUxqYrL1GhvBHZ75VPOwAwODuy8zx7NCeAhqjEdCbEdH96k9btJonUNmQ
 DMM4xsTz+U4121PrF/rIiQoCfUh6KgtMpiJ/Wx+ZJubWLlhKIT5Il52L+OlWGo+H
 3BZU2gCh3Rr46TY5zFbceHwasIQQtqYAmJj5w2LaHPyMD1fBQQvqfnMqam4DoPQF
 Giq54uljQl3xJQUjYOPAy+S+77Rw6OS8pgp7kNDseLn6XE/egrsqJe0jFkzOavP3
 VHOfNoOPzYuSuNorki9bU6EMnC+KqTzB3VAi2cuMmQU3yKPln0QMol04XdEzSITp
 7VR76mXdAIH378PhGJeDmCaXc94UviqFU3HU392jHrD2lhNmSavCd01jgOtMb1q0
 GOwEwY5Tw35eehrc/11tue09wfgl5TqoNW2L4BsKA79GC1OyyWTPqArG/tHYUbLw
 r5hiKZ6FLizGRQk3HzM7fTybnOyv9iKoHHuCubaDNAq7c2mk6TbqfaZLeZ51dqYq
 KR/E5+lslVyNQhGHM2OLPTvcrPEHcO8uD+9C+sPFZPytmvLwblhYBzEB8yxyXUuM
 HwJ0lHnHUVhGx/pgF7tGX8Hq8lGZ61HQBh9u3Cft4uJcFdE28hx5lZU8808I3FYc
 J5kH5fUR1ryG
 =nGA7
 -----END PGP SIGNATURE-----

Merge tag 'pm-5.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix a race condition and an ordering issue related to using
  device links in the runtime PM framework and two kerneldoc comments in
  cpufreq.

  Specifics:

   - Fix race condition related to the handling of supplier devices
     during consumer device probe and fix the order of decrementation of
     two related reference counters in the runtime PM core code handling
     supplier devices (Adrian Hunter).

   - Fix kerneldoc comments in cpufreq that have not been updated along
     with the functions documented by them (Geert Uytterhoeven)"

* tag 'pm-5.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM: runtime: Fix race getting/putting suppliers at probe
  PM: runtime: Fix ordering in pm_runtime_get_suppliers()
  cpufreq: Fix scaling_{available,boost}_frequencies_show() comments
This commit is contained in:
Linus Torvalds 2021-04-02 15:17:08 -07:00
commit 9314a0e9c7
2 changed files with 10 additions and 4 deletions

View File

@ -1690,8 +1690,8 @@ void pm_runtime_get_suppliers(struct device *dev)
device_links_read_lock_held())
if (link->flags & DL_FLAG_PM_RUNTIME) {
link->supplier_preactivated = true;
refcount_inc(&link->rpm_active);
pm_runtime_get_sync(link->supplier);
refcount_inc(&link->rpm_active);
}
device_links_read_unlock(idx);
@ -1704,6 +1704,8 @@ void pm_runtime_get_suppliers(struct device *dev)
void pm_runtime_put_suppliers(struct device *dev)
{
struct device_link *link;
unsigned long flags;
bool put;
int idx;
idx = device_links_read_lock();
@ -1712,7 +1714,11 @@ void pm_runtime_put_suppliers(struct device *dev)
device_links_read_lock_held())
if (link->supplier_preactivated) {
link->supplier_preactivated = false;
if (refcount_dec_not_one(&link->rpm_active))
spin_lock_irqsave(&dev->power.lock, flags);
put = pm_runtime_status_suspended(dev) &&
refcount_dec_not_one(&link->rpm_active);
spin_unlock_irqrestore(&dev->power.lock, flags);
if (put)
pm_runtime_put(link->supplier);
}

View File

@ -267,7 +267,7 @@ struct freq_attr cpufreq_freq_attr_##_name##_freqs = \
__ATTR_RO(_name##_frequencies)
/*
* show_scaling_available_frequencies - show available normal frequencies for
* scaling_available_frequencies_show - show available normal frequencies for
* the specified CPU
*/
static ssize_t scaling_available_frequencies_show(struct cpufreq_policy *policy,
@ -279,7 +279,7 @@ cpufreq_attr_available_freq(scaling_available);
EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
/*
* show_available_boost_freqs - show available boost frequencies for
* scaling_boost_frequencies_show - show available boost frequencies for
* the specified CPU
*/
static ssize_t scaling_boost_frequencies_show(struct cpufreq_policy *policy,