pm24.git/include/linux/cpufreq.h, branch v5.2-rc2

cpufreq: Call transition notifier only once for each policy

2019-05-10T10:20:36Z

Currently, the notifiers are called once for each CPU of the policy->cpus cpumask. It would be more optimal if the notifier can be called only once and all the relevant information be provided to it. Out of the 23 drivers that register for the transition notifiers today, only 4 of them do per-cpu updates and the callback for the rest can be called only once for the policy without any impact. This would also avoid multiple function calls to the notifier callbacks and reduce multiple iterations of notifier core's code (which does locking as well). This patch adds pointer to the cpufreq policy to the struct cpufreq_freqs, so the notifier callback has all the information available to it with a single call. The five drivers which perform per-cpu updates are updated to use the cpufreq policy. The freqs->cpu field is redundant now and is removed. Acked-by: David S. Miller (sparc) Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki

cpufreq: intel_pstate: Update max frequency on global turbo changes

2019-04-08T09:26:09Z

While the cpuinfo.max_freq value doesn't really matter for intel_pstate in the active mode, in the passive mode it is used by governors as the maximum physical frequency of the CPU and the results of governor computations generally depend on it. Also it is made available to user space via sysfs and it should match the current HW configuration. For this reason, make intel_pstate update cpuinfo.max_freq for all CPUs if it detects a global change of turbo frequency settings from "disable" to "enable" or the other way associated with a _PPC change notification from the platform firmware. Note that policy_is_inactive(), cpufreq_cpu_acquire(), cpufreq_cpu_release(), and cpufreq_set_policy() need to be made available to it for this purpose. Link: https://bugzilla.kernel.org/show_bug.cgi?id=200759 Reported-by: Gabriele Mazzotta Tested-by: Gabriele Mazzotta Signed-off-by: Rafael J. Wysocki Acked-by: Viresh Kumar

cpufreq: intel_pstate: Driver-specific handling of _PPC updates

2019-04-01T21:43:05Z

In some cases, the platform firmware disables or enables turbo frequencies for all CPUs globally before triggering a _PPC change notification for one of them. Obviously, that global change affects all CPUs, not just the notified one, and it needs to be acted upon by cpufreq. The intel_pstate driver is able to detect such global changes of the settings, but it also needs to update policy limits for all CPUs if that happens, in particular if turbo frequencies are enabled globally - to allow them to be used. For this reason, introduce a new cpufreq driver callback to be invoked on _PPC notifications, if present, instead of simply calling cpufreq_update_policy() for the notified CPU and make intel_pstate use it to trigger policy updates for all CPUs in the system if global settings change. Link: https://bugzilla.kernel.org/show_bug.cgi?id=200759 Reported-by: Gabriele Mazzotta Tested-by: Gabriele Mazzotta Signed-off-by: Rafael J. Wysocki Acked-by: Viresh Kumar

cpufreq: Allow light-weight tear down and bring up of CPUs

2019-02-12T22:47:42Z

The cpufreq core doesn't remove the cpufreq policy anymore on CPU offline operation, rather that happens when the CPU device gets unregistered from the kernel. This allows faster recovery when the CPU comes back online. This is also very useful during system wide suspend/resume where we offline all non-boot CPUs during suspend and then bring them back on resume. This commit takes the same idea a step ahead to allow drivers to do light weight tear-down and bring-up during CPU offline and online operations. A new set of callbacks is introduced, online/offline(). online() gets called when the first CPU of an inactive policy is brought up and offline() gets called when all the CPUs of a policy are offlined. The existing init/exit() callback get called on policy creation/destruction. They also get called instead of online/offline() callbacks if the online/offline() callbacks aren't provided. This also moves around some code to get executed only for the new-policy case going forward. Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki

cpufreq: Auto-register the driver as a thermal cooling device if asked

2019-01-30T22:02:26Z

All cpufreq drivers do similar things to register as a cooling device. Provide a cpufreq driver flag so drivers can just ask the cpufreq core to register the cooling device on their behalf. This allows us to get rid of duplicated code in the drivers. In order to allow this, we add a struct thermal_cooling_device pointer to struct cpufreq_policy so that drivers don't need to store it in a private data structure. Suggested-by: Stephen Boyd Suggested-by: Viresh Kumar Signed-off-by: Amit Kucheria Reviewed-by: Matthias Kaehlcke Tested-by: Matthias Kaehlcke Acked-by: Viresh Kumar Reviewed-by: Daniel Lezcano Signed-off-by: Rafael J. Wysocki

cpufreq: Use struct kobj_attribute instead of struct global_attr

2019-01-29T10:44:30Z

The cpufreq_global_kobject is created using kobject_create_and_add() helper, which assigns the kobj_type as dynamic_kobj_ktype and show/store routines are set to kobj_attr_show() and kobj_attr_store(). These routines pass struct kobj_attribute as an argument to the show/store callbacks. But all the cpufreq files created using the cpufreq_global_kobject expect the argument to be of type struct attribute. Things work fine currently as no one accesses the "attr" argument. We may not see issues even if the argument is used, as struct kobj_attribute has struct attribute as its first element and so they will both get same address. But this is logically incorrect and we should rather use struct kobj_attribute instead of struct global_attr in the cpufreq core and drivers and the show/store callbacks should take struct kobj_attribute as argument instead. This bug is caught using CFI CLANG builds in android kernel which catches mismatch in function prototypes for such callbacks. Reported-by: Donghee Han Reported-by: Sangkyu Kim Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki

cpufreq: Replace open-coded << with BIT()

2019-01-21T10:02:09Z

Minor clean-up to use BIT() and keep checkpatch happy. Clean up the comment formatting while we're at it to make it easier to read. Signed-off-by: Amit Kucheria Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki

sched/topology: Make Energy Aware Scheduling depend on schedutil

2018-12-11T14:17:00Z

Energy Aware Scheduling (EAS) is designed with the assumption that frequencies of CPUs follow their utilization value. When using a CPUFreq governor other than schedutil, the chances of this assumption being true are small, if any. When schedutil is being used, EAS' predictions are at least consistent with the frequency requests. Although those requests have no guarantees to be honored by the hardware, they should at least guide DVFS in the right direction and provide some hope in regards to the EAS model being accurate. To make sure EAS is only used in a sane configuration, create a strong dependency on schedutil being used. Since having sugov compiled-in does not provide that guarantee, make CPUFreq call a scheduler function on governor changes hence letting it rebuild the scheduling domains, check the governors of the online CPUs, and enable/disable EAS accordingly. Signed-off-by: Quentin Perret Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Thomas Gleixner Cc: adharmap@codeaurora.org Cc: chris.redpath@arm.com Cc: currojerez@riseup.net Cc: dietmar.eggemann@arm.com Cc: edubezval@gmail.com Cc: gregkh@linuxfoundation.org Cc: javi.merino@kernel.org Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: morten.rasmussen@arm.com Cc: patrick.bellasi@arm.com Cc: pkondeti@codeaurora.org Cc: skannan@codeaurora.org Cc: smuckle@google.com Cc: srinivas.pandruvada@linux.intel.com Cc: thara.gopinath@linaro.org Cc: tkjos@google.com Cc: valentin.schneider@arm.com Cc: vincent.guittot@linaro.org Cc: viresh.kumar@linaro.org Link: https://lkml.kernel.org/r/20181203095628.11858-9-quentin.perret@arm.com Signed-off-by: Ingo Molnar

cpufreq: Rename cpufreq_can_do_remote_dvfs()

2018-05-23T08:37:08Z

This routine checks if the CPU running this code belongs to the policy of the target CPU or if not, can it do remote DVFS for it remotely. But the current name of it implies as if it is only about doing remote updates. Rename it to make it more relevant. Suggested-by: Rafael J. Wysocki Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki

cpufreq: Drop cpufreq_table_validate_and_show()

2018-04-10T06:40:45Z

This isn't used anymore. Remove the helper and update documentation accordingly. Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki