Commit 7c404c62 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'pm-reverts-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm 

Pull power management commit reverts from Rafael Wysocki:
 "Since Geert reports additional problems with my PM QoS fix from the
  last week that have not been addressed by the most recent fixup on top
  of it, they both should better be reverted now and let's fix the
  original issue properly in 4.15.

  This reverts two recent PM QoS commits one of which introduced
  multiple problems and the other one fixed some, but not all of them
  (Rafael Wysocki)"

* tag 'pm-reverts-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  Revert "PM / QoS: Fix device resume latency PM QoS"
  Revert "PM / QoS: Fix default runtime_pm device resume latency"
parents 287683d0 d5919dcc

Documentation/ABI/testing/sysfs-devices-power

+1 −3
Original line number Diff line number Diff line
@@ -211,9 +211,7 @@ Description: 
		device, after it has been suspended at run time, from a resume

		request to the moment the device will be ready to process I/O,

		in microseconds.  If it is equal to 0, however, this means that

		the PM QoS resume latency may be arbitrary and the special value

		"n/a" means that user space cannot accept any resume latency at

		all for the given device.

		the PM QoS resume latency may be arbitrary.



		Not all drivers support this attribute.  If it isn't supported,

		it is not present.

drivers/base/cpu.c

+1 −2
Original line number Diff line number Diff line
@@ -377,8 +377,7 @@ int register_cpu(struct cpu *cpu, int num) 


	per_cpu(cpu_sys_devices, num) = &cpu->dev;

	register_cpu_under_node(num, cpu_to_node(num));

	dev_pm_qos_expose_latency_limit(&cpu->dev,

					PM_QOS_RESUME_LATENCY_NO_CONSTRAINT);

	dev_pm_qos_expose_latency_limit(&cpu->dev, 0);



	return 0;

}

drivers/base/power/domain_governor.c

+23 −30
Original line number Diff line number Diff line
@@ -14,20 +14,23 @@ 
static int dev_update_qos_constraint(struct device *dev, void *data)

{

	s64 *constraint_ns_p = data;

	s64 constraint_ns = -1;

	s32 constraint_ns = -1;



	if (dev->power.subsys_data && dev->power.subsys_data->domain_data)

		constraint_ns = dev_gpd_data(dev)->td.effective_constraint_ns;



	if (constraint_ns < 0)

	if (constraint_ns < 0) {

		constraint_ns = dev_pm_qos_read_value(dev);



	if (constraint_ns == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT)

		return 0;



		constraint_ns *= NSEC_PER_USEC;

	}

	if (constraint_ns == 0)

		return 0;



	if (constraint_ns < *constraint_ns_p || *constraint_ns_p < 0)

	/*

	 * constraint_ns cannot be negative here, because the device has been

	 * suspended.

	 */

	if (constraint_ns < *constraint_ns_p || *constraint_ns_p == 0)

		*constraint_ns_p = constraint_ns;



	return 0;
@@ -60,14 +63,10 @@ static bool default_suspend_ok(struct device *dev) 


	spin_unlock_irqrestore(&dev->power.lock, flags);



	if (constraint_ns == 0)

	if (constraint_ns < 0)

		return false;



	if (constraint_ns == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT)

		constraint_ns = -1;

	else

	constraint_ns *= NSEC_PER_USEC;



	/*

	 * We can walk the children without any additional locking, because

	 * they all have been suspended at this point and their
@@ -77,19 +76,14 @@ static bool default_suspend_ok(struct device *dev) 
		device_for_each_child(dev, &constraint_ns,

				      dev_update_qos_constraint);



	if (constraint_ns < 0) {

		/* The children have no constraints. */

		td->effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;

		td->cached_suspend_ok = true;

	} else {

		constraint_ns -= td->suspend_latency_ns + td->resume_latency_ns;

	if (constraint_ns > 0) {

			td->effective_constraint_ns = constraint_ns;

			td->cached_suspend_ok = true;

		} else {

			td->effective_constraint_ns = 0;

		}

		constraint_ns -= td->suspend_latency_ns +

				td->resume_latency_ns;

		if (constraint_ns == 0)

			return false;

	}

	td->effective_constraint_ns = constraint_ns;

	td->cached_suspend_ok = constraint_ns >= 0;



	/*

	 * The children have been suspended already, so we don't need to take
@@ -151,13 +145,12 @@ static bool __default_power_down_ok(struct dev_pm_domain *pd, 
		td = &to_gpd_data(pdd)->td;

		constraint_ns = td->effective_constraint_ns;

		/* default_suspend_ok() need not be called before us. */

		if (constraint_ns < 0)

		if (constraint_ns < 0) {

			constraint_ns = dev_pm_qos_read_value(pdd->dev);



		if (constraint_ns == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT)

			continue;



			constraint_ns *= NSEC_PER_USEC;

		}

		if (constraint_ns == 0)

			continue;



		/*

		 * constraint_ns cannot be negative here, because the device has

drivers/base/power/qos.c

+1 −1
Original line number Diff line number Diff line
@@ -189,7 +189,7 @@ static int dev_pm_qos_constraints_allocate(struct device *dev) 
	plist_head_init(&c->list);

	c->target_value = PM_QOS_RESUME_LATENCY_DEFAULT_VALUE;

	c->default_value = PM_QOS_RESUME_LATENCY_DEFAULT_VALUE;

	c->no_constraint_value = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;

	c->no_constraint_value = PM_QOS_RESUME_LATENCY_DEFAULT_VALUE;

	c->type = PM_QOS_MIN;

	c->notifiers = n;

drivers/base/power/runtime.c

+1 −1
Original line number Diff line number Diff line
@@ -253,7 +253,7 @@ static int rpm_check_suspend_allowed(struct device *dev) 
	    || (dev->power.request_pending

			&& dev->power.request == RPM_REQ_RESUME))

		retval = -EAGAIN;

	else if (__dev_pm_qos_read_value(dev) == 0)

	else if (__dev_pm_qos_read_value(dev) < 0)

		retval = -EPERM;

	else if (dev->power.runtime_status == RPM_SUSPENDED)

		retval = 1;

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