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Power management fixes for 5.8-rc3

Browse source 
- Make sure that the _TIF_POLLING_NRFLAG is clear before entering
    the last phase of suspend-to-idle to avoid wakeup issues on some
    x86 systems (Chen Yu, Rafael Wysocki).
 
  - Cover one more case in which the intel_pstate driver should let
    the platform firmware control the CPU frequency and refuse to
    load (Srinivas Pandruvada).
 
  - Add __init annotations to 2 functions in the power management
    core (Christophe JAILLET).
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Merge tag 'pm-5.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix a recent regression that broke suspend-to-idle on some x86
  systems, fix the intel_pstate driver to correctly let the platform
  firmware control CPU performance in some cases and add __init
  annotations to a couple of functions.

  Specifics:

   - Make sure that the _TIF_POLLING_NRFLAG is clear before entering the
     last phase of suspend-to-idle to avoid wakeup issues on some x86
     systems (Chen Yu, Rafael Wysocki).

   - Cover one more case in which the intel_pstate driver should let the
     platform firmware control the CPU frequency and refuse to load
     (Srinivas Pandruvada).

   - Add __init annotations to 2 functions in the power management core
     (Christophe JAILLET)"

* tag 'pm-5.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpuidle: Rearrange s2idle-specific idle state entry code
  PM: sleep: core: mark 2 functions as __init to save some memory
  cpufreq: intel_pstate: Add one more OOB control bit
  PM: s2idle: Clear _TIF_POLLING_NRFLAG before suspend to idle
This commit is contained in:
Linus Torvalds 2020-06-26 12:32:11 -07:00
commit ed3e00e7d6
4 changed files with 21 additions and 10 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
drivers/base/power/trace.c
View file

@ -265,14 +265,14 @@ static struct notifier_block pm_trace_nb = {
.notifier_call = pm_trace_notify,
};
static int early_resume_init(void)
static int __init early_resume_init(void)
{
hash_value_early_read = read_magic_time();
register_pm_notifier(&pm_trace_nb);
return 0;
}
static int late_resume_init(void)
static int __init late_resume_init(void)
{
unsigned int val = hash_value_early_read;
unsigned int user, file, dev;

7
drivers/cpufreq/intel_pstate.c
View file

@ -2677,6 +2677,8 @@ static struct acpi_platform_list plat_info[] __initdata = {
{ } /* End */
};
#define BITMASK_OOB (BIT(8) | BIT(18))
static bool __init intel_pstate_platform_pwr_mgmt_exists(void)
{
const struct x86_cpu_id *id;
@ -2686,8 +2688,9 @@ static bool __init intel_pstate_platform_pwr_mgmt_exists(void)
id = x86_match_cpu(intel_pstate_cpu_oob_ids);
if (id) {
rdmsrl(MSR_MISC_PWR_MGMT, misc_pwr);
if (misc_pwr & (1 << 8)) {
pr_debug("Bit 8 in the MISC_PWR_MGMT MSR set\n");
if (misc_pwr & BITMASK_OOB) {
pr_debug("Bit 8 or 18 in the MISC_PWR_MGMT MSR set\n");
pr_debug("P states are controlled in Out of Band mode by the firmware/hardware\n");
return true;
}
}

5
drivers/cpuidle/cpuidle.c
View file

@ -186,9 +186,10 @@ int cpuidle_enter_s2idle(struct cpuidle_driver *drv, struct cpuidle_device *dev)
* be frozen safely.
*/
index = find_deepest_state(drv, dev, U64_MAX, 0, true);
if (index > 0)
if (index > 0) {
enter_s2idle_proper(drv, dev, index);
local_irq_enable();
}
return index;
}
#endif /* CONFIG_SUSPEND */

15
kernel/sched/idle.c
View file

@ -96,6 +96,15 @@ void __cpuidle default_idle_call(void)
}
}
static int call_cpuidle_s2idle(struct cpuidle_driver *drv,
struct cpuidle_device *dev)
{
if (current_clr_polling_and_test())
return -EBUSY;
return cpuidle_enter_s2idle(drv, dev);
}
static int call_cpuidle(struct cpuidle_driver *drv, struct cpuidle_device *dev,
int next_state)
{
@ -171,11 +180,9 @@ static void cpuidle_idle_call(void)
if (idle_should_enter_s2idle()) {
rcu_idle_enter();
entered_state = cpuidle_enter_s2idle(drv, dev);
if (entered_state > 0) {
local_irq_enable();
entered_state = call_cpuidle_s2idle(drv, dev);
if (entered_state > 0)
goto exit_idle;
}
rcu_idle_exit();