Commit 8c76163f authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'pm-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm 

Pull power management fixes from Rafael Wysocki:
 "Update cpufreq documentation to match the code after recent changes
  (Christian Loehle), fix a units conversion issue in the CPPC cpufreq
  driver (liwei), and fix an error check in the dtpm_devfreq power
  capping driver (Yuan Can)"

* tag 'pm-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: CPPC: fix perf_to_khz/khz_to_perf conversion exception
  powercap: dtpm_devfreq: Fix error check against dev_pm_qos_add_request()
  cpufreq: docs: Reflect latency changes in docs
parents 48005a5a 1646a3f2

Documentation/admin-guide/pm/cpufreq.rst

+10 −10
Original line number Diff line number Diff line
@@ -425,8 +425,8 @@ This governor exposes only one tunable: 


``rate_limit_us``

	Minimum time (in microseconds) that has to pass between two consecutive

	runs of governor computations (default: 1000 times the scaling driver's

	transition latency).

	runs of governor computations (default: 1.5 times the scaling driver's

	transition latency or the maximum 2ms).



	The purpose of this tunable is to reduce the scheduler context overhead

	of the governor which might be excessive without it.
@@ -474,17 +474,17 @@ This governor exposes the following tunables: 
	This is how often the governor's worker routine should run, in

	microseconds.



	Typically, it is set to values of the order of 10000 (10 ms).  Its

	default value is equal to the value of ``cpuinfo_transition_latency``

	for each policy this governor is attached to (but since the unit here

	is greater by 1000, this means that the time represented by

	``sampling_rate`` is 1000 times greater than the transition latency by

	default).

	Typically, it is set to values of the order of 2000 (2 ms).  Its

	default value is to add a 50% breathing room

	to ``cpuinfo_transition_latency`` on each policy this governor is

	attached to. The minimum is typically the length of two scheduler

	ticks.



	If this tunable is per-policy, the following shell command sets the time

	represented by it to be 750 times as high as the transition latency::

	represented by it to be 1.5 times as high as the transition latency

	(the default)::



	# echo `$(($(cat cpuinfo_transition_latency) * 750 / 1000)) > ondemand/sampling_rate

	# echo `$(($(cat cpuinfo_transition_latency) * 3 / 2)) > ondemand/sampling_rate



``up_threshold``

	If the estimated CPU load is above this value (in percent), the governor

drivers/acpi/cppc_acpi.c

+17 −5
Original line number Diff line number Diff line
@@ -1916,9 +1916,15 @@ unsigned int cppc_perf_to_khz(struct cppc_perf_caps *caps, unsigned int perf) 
	u64 mul, div;



	if (caps->lowest_freq && caps->nominal_freq) {

		/* Avoid special case when nominal_freq is equal to lowest_freq */

		if (caps->lowest_freq == caps->nominal_freq) {

			mul = caps->nominal_freq;

			div = caps->nominal_perf;

		} else {

			mul = caps->nominal_freq - caps->lowest_freq;

		mul *= KHZ_PER_MHZ;

			div = caps->nominal_perf - caps->lowest_perf;

		}

		mul *= KHZ_PER_MHZ;

		offset = caps->nominal_freq * KHZ_PER_MHZ -

			 div64_u64(caps->nominal_perf * mul, div);

	} else {
@@ -1942,8 +1948,14 @@ unsigned int cppc_khz_to_perf(struct cppc_perf_caps *caps, unsigned int freq) 
	u64 mul, div;



	if (caps->lowest_freq && caps->nominal_freq) {

		/* Avoid special case when nominal_freq is equal to lowest_freq */

		if (caps->lowest_freq == caps->nominal_freq) {

			mul = caps->nominal_perf;

			div = caps->nominal_freq;

		} else {

			mul = caps->nominal_perf - caps->lowest_perf;

			div = caps->nominal_freq - caps->lowest_freq;

		}

		/*

		 * We don't need to convert to kHz for computing offset and can

		 * directly use nominal_freq and lowest_freq as the div64_u64

drivers/powercap/dtpm_devfreq.c

+1 −1
Original line number Diff line number Diff line
@@ -178,7 +178,7 @@ static int __dtpm_devfreq_setup(struct devfreq *devfreq, struct dtpm *parent) 
	ret = dev_pm_qos_add_request(dev, &dtpm_devfreq->qos_req,

				     DEV_PM_QOS_MAX_FREQUENCY,

				     PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE);

	if (ret) {

	if (ret < 0) {

		pr_err("Failed to add QoS request: %d\n", ret);

		goto out_dtpm_unregister;

	}