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 <davem@davemloft.net> (sparc)
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Merge tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
Pull printk updates from Petr Mladek:
- Allow state reset of printk_once() calls.
- Prevent crashes when dereferencing invalid pointers in vsprintf().
Only the first byte is checked for simplicity.
- Make vsprintf warnings consistent and inlined.
- Treewide conversion of obsolete %pf, %pF to %ps, %pF printf
modifiers.
- Some clean up of vsprintf and test_printf code.
* tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
lib/vsprintf: Make function pointer_string static
vsprintf: Limit the length of inlined error messages
vsprintf: Avoid confusion between invalid address and value
vsprintf: Prevent crash when dereferencing invalid pointers
vsprintf: Consolidate handling of unknown pointer specifiers
vsprintf: Factor out %pO handler as kobject_string()
vsprintf: Factor out %pV handler as va_format()
vsprintf: Factor out %p[iI] handler as ip_addr_string()
vsprintf: Do not check address of well-known strings
vsprintf: Consistent %pK handling for kptr_restrict == 0
vsprintf: Shuffle restricted_pointer()
printk: Tie printk_once / printk_deferred_once into .data.once for reset
treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively
lib/test_printf: Switch to bitmap_zalloc()
Currently the error return path from kobject_init_and_add() is not
followed by a call to kobject_put() - which means we are leaking the
kobject.
Fix it by adding a call to kobject_put() in the error path of
kobject_init_and_add().
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Tobin C. Harding <tobin@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currenly, __cpufreq_get() called by show_cpuinfo_cur_freq() will check
->get callback. That is needless since cpuinfo_cur_freq attribute will
not be created if ->get is not set. So let's drop it in __cpufreq_get().
Also keep this check in cpufreq_get().
Signed-off-by: Yue Hu <huyue2@yulong.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Initially, bios_limit attribute will be created if driver->bios_limit
is set in cpufreq_add_dev_interface(). So remove the redundant check
for latter show operation.
Signed-off-by: Yue Hu <huyue2@yulong.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently there are three calling paths for cpufreq_boost_supported() in
all as below, we can see the cpufreq_driver null check is needless since
it is already checked before.
<path1>
cpufreq_enable_boost_support()
|-> if (!cpufreq_driver)
|-> cpufreq_boost_supported()
<path2>
cpufreq_register_driver()
|-> if (!driver_data ...
|-> cpufreq_driver = driver_data
|-> cpufreq_boost_supported()
|-> remove_boost_sysfs_file()
|-> cpufreq_boost_supported()
<path3>
cpufreq_unregister_driver()
|-> if (!cpufreq_driver ...
|-> remove_boost_sysfs_file()
|-> cpufreq_boost_supported()
Signed-off-by: Yue Hu <huyue2@yulong.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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 <gabriele.mzt@gmail.com>
Tested-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
It sometimes is necessary to find a cpufreq policy for a given CPU
and acquire its rwsem (for writing) immediately after that, so
introduce cpufreq_cpu_acquire() as a helper for that and the
complementary cpufreq_cpu_release().
Make cpufreq_update_policy() use the new functions.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
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 <gabriele.mzt@gmail.com>
Tested-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Fix the formatting of the cpufreq_cpu_get() and cpufreq_cpu_put()
kerneldoc comments and rework them to be somewhat easier to follow.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The invocation of the ->setpolicy() cpufreq driver callback should
be equivalent to calling cpufreq_governor_limits(policy) for drivers
with internal governors, but in fact it isn't so, because the
temporary new_policy object is passed to it instead of the updated
policy.
That is a bit confusing, so make cpufreq_set_policy() pass the
updated policy to the driver ->setpolicy() callback.
No intentional changes of behavior.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Remove the redundant "cpufreq:" prefix from two debug messages in
cpufreq_set_policy().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
In cpufreq_update_policy(), instead of updating new_policy.cur
separately, which is kind of confusing, because cpufreq_set_policy()
doesn't take that value into account directly anyway, make the copy
of the existing policy after calling cpufreq_update_current_freq().
No intentional changes of behavior.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Add kerneldoc comments describing cpufreq_set_policy() and
cpufreq_update_policy() as they have not been properly documented
so far and they really need to be documented.
While at it, fix white space around the cpufreq_set_policy() header.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Double NOT (!!) operation is normally done to convert a non-zero value
to 1 and keep zero as is, but that isn't the requirement in this case.
All we wanted was to make sure that only one of the two routines isn't
set, i.e. either both function pointers are set or both are unset.
This can be done with a single NOT (!) operation as well.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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 <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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 <swboyd@chromium.org>
Suggested-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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 <dh.han@samsung.com>
Reported-by: Sangkyu Kim <skwith.kim@samsung.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The local variable "new_policy" hasn't been used in the error path of
cpufreq_online() since commit f9f41e3ef9 (cpufreq: Remove policy
create/remove notifiers). Don't update it in that error path.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpuinfo_cur_freq gets current CPU frequency as detected by hardware
while scaling_cur_freq last known CPU frequency. Some platforms may not
allow checking the CPU frequency of an offline CPU or the associated
resources may have been released via cpufreq_exit when the CPU gets
offlined, in which case the policy would have been invalidated already.
If we attempt to get current frequency from the hardware, it may result
in hang or crash.
For example on Juno, I see:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000188
[0000000000000188] pgd=0000000000000000
Internal error: Oops: 96000004 [#1] PREEMPT SMP
Modules linked in:
CPU: 5 PID: 4202 Comm: cat Not tainted 4.20.0-08251-ga0f2c0318a15-dirty #87
Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform
pstate: 40000005 (nZcv daif -PAN -UAO)
pc : scmi_cpufreq_get_rate+0x34/0xb0
lr : scmi_cpufreq_get_rate+0x34/0xb0
Call trace:
scmi_cpufreq_get_rate+0x34/0xb0
__cpufreq_get+0x34/0xc0
show_cpuinfo_cur_freq+0x24/0x78
show+0x40/0x60
sysfs_kf_seq_show+0xc0/0x148
kernfs_seq_show+0x44/0x50
seq_read+0xd4/0x480
kernfs_fop_read+0x15c/0x208
__vfs_read+0x60/0x188
vfs_read+0x94/0x150
ksys_read+0x6c/0xd8
__arm64_sys_read+0x24/0x30
el0_svc_common+0x78/0x100
el0_svc_handler+0x38/0x78
el0_svc+0x8/0xc
---[ end trace 3d1024e58f77f6b2 ]---
So fix the issue by checking if the policy is invalid early in
__cpufreq_get before attempting to get the current frequency.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
WARN_ON() already contains an unlikely(), so it's not necessary to wrap it
into another.
Signed-off-by: Igor Stoppa <igor.stoppa@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
With lockdep turned on, the following circular lock dependency problem
was reported:
[ 57.470040] ======================================================
[ 57.502900] WARNING: possible circular locking dependency detected
[ 57.535208] 4.18.0-0.rc3.1.el8+7.x86_64+debug #1 Tainted: G
[ 57.577761] ------------------------------------------------------
[ 57.609714] tuned/1505 is trying to acquire lock:
[ 57.633808] 00000000559deec5 (cpu_hotplug_lock.rw_sem){++++}, at: store+0x27/0x120
[ 57.672880]
[ 57.672880] but task is already holding lock:
[ 57.702184] 000000002136ca64 (kn->count#118){++++}, at: kernfs_fop_write+0x1d0/0x410
[ 57.742176]
[ 57.742176] which lock already depends on the new lock.
[ 57.742176]
[ 57.785220]
[ 57.785220] the existing dependency chain (in reverse order) is:
:
[ 58.932512] other info that might help us debug this:
[ 58.932512]
[ 58.973344] Chain exists of:
[ 58.973344] cpu_hotplug_lock.rw_sem --> subsys mutex#5 --> kn->count#118
[ 58.973344]
[ 59.030795] Possible unsafe locking scenario:
[ 59.030795]
[ 59.061248] CPU0 CPU1
[ 59.085377] ---- ----
[ 59.108160] lock(kn->count#118);
[ 59.124935] lock(subsys mutex#5);
[ 59.156330] lock(kn->count#118);
[ 59.186088] lock(cpu_hotplug_lock.rw_sem);
[ 59.208541]
[ 59.208541] *** DEADLOCK ***
In the cpufreq_register_driver() function, the lock sequence is:
cpus_read_lock --> kn->count
For the cpufreq sysfs store method, the lock sequence is:
kn->count --> cpus_read_lock
These sequences are actually safe as they are taking a share lock on
cpu_hotplug_lock. However, the current lockdep code doesn't check for
share locking when detecting circular lock dependency. Fixing that
could be a substantial effort.
Instead, we can work around this problem by using cpus_read_trylock()
in the store method which is much simpler. The chance of not getting
the read lock is very small. If that happens, the userspace application
that writes the sysfs file will get an error.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
systrace used for tracing for Android systems has carried a patch for
many years in the Android tree that traces when the cpufreq limits
change. With the help of this information, systrace can know when the
policy limits change and can visually display the data. Lets add
upstream support for the same.
Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Use the static SRCU initializer for `cpufreq_transition_notifier_list'.
This avoids the init_cpufreq_transition_notifier_list() initcall. Its
only purpose is to initialize the SRCU notifier once during boot and set
another variable which is used as an indicator whether the init was
perfromed before cpufreq_register_notifier() was used.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If the policy limits are updated via cpufreq_update_policy() and
subsequently via sysfs, the limits stored in user_policy may be
set incorrectly.
For example, if both min and max are set via sysfs to the maximum
available frequency, user_policy.min and user_policy.max will also
be the maximum. If a policy notifier triggered by
cpufreq_update_policy() lowers both the min and the max at this
point, that change is not reflected by the user_policy limits, so
if the max is updated again via sysfs to the same lower value,
then user_policy.max will be lower than user_policy.min which
shouldn't happen. In particular, if one of the policy CPUs is
then taken offline and back online, cpufreq_set_policy() will
fail for it due to a failing limits check.
To prevent that from happening, initialize the min and max fields
of the new_policy object to the ones stored in user_policy that
were previously set via sysfs.
Signed-off-by: Kevin Wangtao <kevin.wangtao@hisilicon.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Subject & changelog ]
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq_notify_transition() calls __cpufreq_notify_transition() for each
CPU of a policy. There is a lot of code in __cpufreq_notify_transition()
though which isn't required to be executed for each CPU, like checking
about disabled cpufreq or irqs, adjusting jiffies, updating cpufreq
stats and some debug print messages.
This commit merges __cpufreq_notify_transition() into
cpufreq_notify_transition() and modifies cpufreq_notify_transition() to
execute minimum amount of code for each CPU.
Also fix the kerneldoc for cpufreq_notify_transition() while at it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The cpufreq table is already validated by the cpufreq core and none of
the users of cpufreq_generic_init() have any dependency on it to
validate the table as well.
Don't validate the cpufreq table anymore from cpufreq_generic_init().
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
By design, cpufreq drivers are responsible for calling
cpufreq_frequency_table_cpuinfo() from their ->init()
callbacks to validate the frequency table.
However, if a cpufreq driver is buggy and fails to do so properly, it
lead to unexpected behavior of the driver or the cpufreq core at a
later point in time. It would be better if the core could
validate the frequency table during driver initialization.
To that end, introduce cpufreq_table_validate_and_sort() and make
the cpufreq core call it right after invoking the ->init() callback
of the driver and destroy the cpufreq policy if the table is invalid.
For the time being the validation of the table happens twice, once
from the driver and then from the core. The individual drivers will
be updated separately to drop table validation if they don't need it
for other reasons.
The frequency table is marked "sorted" or "unsorted" by the new helper
now instead of in cpufreq_table_validate_and_show(), as it should only
be done after validating the table (which the drivers won't do going
forward).
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Subject/changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Ideally the de-allocation of resources should happen in the exact
opposite order in which they were allocated. It helps maintain the code
in long term, even if nothing really breaks with incorrect ordering.
That wasn't followed in cpufreq_online() and it has some
inconsistencies. For example, the symlinks were created from within
the locked region while they are removed only after putting the locks.
Also ->exit() should have been called only after the symlinks are
removed and the lock is dropped, as that was the case when ->init()
was first called.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq_resume can be called even without preceding cpufreq_suspend.
This can happen in following scenario:
suspend_devices_and_enter
--> dpm_suspend_start
--> dpm_prepare
--> device_prepare : this function errors out
--> dpm_suspend: this is skipped due to dpm_prepare failure
this means cpufreq_suspend is skipped over
--> goto Recover_platform, due to previous error
--> goto Resume_devices
--> dpm_resume_end
--> dpm_resume
--> cpufreq_resume
In case schedutil is used as frequency governor, cpufreq_resume will
eventually call sugov_start, which does following:
memset(sg_cpu, 0, sizeof(*sg_cpu));
....
This effectively erases function pointer for frequency update, causing
crash later on. The function pointer would have been set correctly if
subsequent cpufreq_add_update_util_hook runs successfully, but that
function returns earlier because cpufreq_suspend was not called:
if (WARN_ON(per_cpu(cpufreq_update_util_data, cpu)))
return;
The fix is to check cpufreq_suspended first, if it's false, that means
cpufreq_suspend was not called in the first place, so do not resume
cpufreq.
Signed-off-by: Bo Yan <byan@nvidia.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Dropped printing a message ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
It is possible to remove a cpufreq governor module after
cpufreq_parse_governor() has returned success in
store_scaling_governor() and before cpufreq_set_policy()
acquires a reference to it, because the governor list is
not protected during that period and nothing prevents the
governor from being unregistered then.
Prevent that from happening by acquiring an extra reference
to the governor module temporarily in cpufreq_parse_governor(),
under cpufreq_governor_mutex, and dropping it in
store_scaling_governor(), when cpufreq_set_policy() returns.
Note that the second cpufreq_parse_governor() call site is fine,
because it only cares about the policy member of new_policy.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Drop a pointless return statement from cpufreq_unregister_governor().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pass policy pointer to cpufreq_parse_governor() instead of passing
pointers to two members of it so as to make the code slightly more
straightforward.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Drop an unnecessary local variable from cpufreq_parse_governor()
and rearrange the code in there to make it easier to follow.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Frequency-invariant accounting support based on the ratio of current
frequency and maximum supported frequency is an optional feature an arch
can implement.
Since there are cpufreq drivers (e.g. cpufreq-dt) which can be build for
different arch's a default implementation of the frequency-invariance
setter function arch_set_freq_scale() is needed.
This default implementation is an empty weak function which will be
overwritten by a strong function in case the arch provides one.
The setter function passes the cpumask of related (to the frequency
change) cpus (online and offline cpus), the (new) current frequency and
the maximum supported frequency.
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* pm-cpufreq-sched:
cpufreq: schedutil: Always process remote callback with slow switching
cpufreq: schedutil: Don't restrict kthread to related_cpus unnecessarily
cpufreq: Return 0 from ->fast_switch() on errors
cpufreq: Simplify cpufreq_can_do_remote_dvfs()
cpufreq: Process remote callbacks from any CPU if the platform permits
sched: cpufreq: Allow remote cpufreq callbacks
cpufreq: schedutil: Use unsigned int for iowait boost
cpufreq: schedutil: Make iowait boost more energy efficient
If transition_delay_us isn't defined by the cpufreq driver, the default
value of transition delay (time after which the cpufreq governor will
try updating the frequency again) is currently calculated by multiplying
transition_latency (nsec) with LATENCY_MULTIPLIER (1000) and then
converting this time to usec. That gives the exact same value as
transition_latency, just that the time unit is usec instead of nsec.
With acpi-cpufreq for example, transition_latency is set to around 10
usec and we get transition delay as 10 ms. Which seems to be a
reasonable amount of time to reevaluate the frequency again.
But for platforms where frequency switching isn't that fast (like ARM),
the transition_latency varies from 500 usec to 3 ms, and the transition
delay becomes 500 ms to 3 seconds. Of course, that is a pretty bad
default value to start with.
We can try to come across a better formula (instead of multiplying with
LATENCY_MULTIPLIER) to solve this problem, but will that be worth it ?
This patch tries a simple approach and caps the maximum value of default
transition delay to 10 ms. Of course, userspace can still come in and
change this value anytime or individual drivers can rather provide
transition_delay_us instead.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CPUFREQ_ENTRY_INVALID is a special symbol which is used to specify that
an entry in the cpufreq table is invalid. But using it outside of the
scope of the cpufreq table looks a bit incorrect.
We can represent an invalid frequency by writing it as 0 instead if we
need. Note that it is already done that way for the return value of the
->get() callback.
Lets do the same for ->fast_switch() and not use CPUFREQ_ENTRY_INVALID
outside of the scope of cpufreq table.
Also update the comment over cpufreq_driver_fast_switch() to clearly
mention what this returns.
None of the drivers return CPUFREQ_ENTRY_INVALID as of now from
->fast_switch() callback and so we don't need to update any of those.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
With the recent updates, CPUFREQ_ETERNAL is only used by the drivers
which don't know their transition latency but want to use dynamic
switching.
Anyway, the routine cpufreq_policy_transition_delay_us() caps the value
of transition latency to 10 ms now and that can be used safely with such
platforms.
Remove the check from cpufreq_init_governor() and allow dynamic
switching for such configurations as well.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The policy->transition_latency field is used for multiple purposes
today and its not straight forward at all. This is how it is used:
A. Set the correct transition_latency value.
B. Set it to CPUFREQ_ETERNAL because:
1. We don't want automatic dynamic switching (with
ondemand/conservative) to happen at all.
2. We don't know the transition latency.
This patch handles the B.1. case in a more readable way. A new flag for
the cpufreq drivers is added to disallow use of cpufreq governors which
have dynamic_switching flag set.
All the current cpufreq drivers which are setting transition_latency
unconditionally to CPUFREQ_ETERNAL are updated to use it. They don't
need to set transition_latency anymore.
There shouldn't be any functional change after this patch.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There is no limitation in the ondemand or conservative governors which
disallow the transition_latency to be greater than 10 ms.
The max_transition_latency field is rather used to disallow automatic
dynamic frequency switching for platforms which didn't wanted these
governors to run.
Replace max_transition_latency with a boolean (dynamic_switching) and
check for transition_latency == CPUFREQ_ETERNAL along with that. This
makes it pretty straight forward to read/understand now.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The policy->transition_delay_us field is used only by the schedutil
governor currently, and this field describes how fast the driver wants
the cpufreq governor to change CPUs frequency. It should rather be a
common thing across all governors, as it doesn't have any schedutil
dependency here.
Create a new helper cpufreq_policy_transition_delay_us() to get the
transition delay across all governors.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- Rework suspend-to-idle to allow it to take wakeup events signaled
by the EC into account on ACPI-based platforms in order to properly
support power button wakeup from suspend-to-idle on recent Dell
laptops (Rafael Wysocki).
That includes the core suspend-to-idle code rework, support for
the Low Power S0 _DSM interface, and support for the ACPI INT0002
Virtual GPIO device from Hans de Goede (required for USB keyboard
wakeup from suspend-to-idle to work on some machines).
- Stop trying to export the current CPU frequency via /proc/cpuinfo
on x86 as that is inaccurate and confusing (Len Brown).
- Rework the way in which the current CPU frequency is exported by
the kernel (over the cpufreq sysfs interface) on x86 systems with
the APERF and MPERF registers by always using values read from
these registers, when available, to compute the current frequency
regardless of which cpufreq driver is in use (Len Brown).
- Rework the PCI/ACPI device wakeup infrastructure to remove the
questionable and artificial distinction between "devices that
can wake up the system from sleep states" and "devices that can
generate wakeup signals in the working state" from it, which
allows the code to be simplified quite a bit (Rafael Wysocki).
- Fix the wakeup IRQ framework by making it use SRCU instead of
RCU which doesn't allow sleeping in the read-side critical
sections, but which in turn is expected to be allowed by the
IRQ bus locking infrastructure (Thomas Gleixner).
- Modify some computations in the intel_pstate driver to avoid
rounding errors resulting from them (Srinivas Pandruvada).
- Reduce the overhead of the intel_pstate driver in the HWP
(hardware-managed P-states) mode and when the "performance"
P-state selection algorithm is in use by making it avoid
registering scheduler callbacks in those cases (Len Brown).
- Rework the energy_performance_preference sysfs knob in
intel_pstate by changing the values that correspond to
different symbolic hint names used by it (Len Brown).
- Make it possible to use more than one cpuidle driver at the same
time on ARM (Daniel Lezcano).
- Make it possible to prevent the cpuidle menu governor from using
the 0 state by disabling it via sysfs (Nicholas Piggin).
- Add support for FFH (Fixed Functional Hardware) MWAIT in ACPI C1
on AMD systems (Yazen Ghannam).
- Make the CPPC cpufreq driver take the lowest nonlinear performance
information into account (Prashanth Prakash).
- Add support for hi3660 to the cpufreq-dt driver, fix the
imx6q driver and clean up the sfi, exynos5440 and intel_pstate
drivers (Colin Ian King, Krzysztof Kozlowski, Octavian Purdila,
Rafael Wysocki, Tao Wang).
- Fix a few minor issues in the generic power domains (genpd)
framework and clean it up somewhat (Krzysztof Kozlowski,
Mikko Perttunen, Viresh Kumar).
- Fix a couple of minor issues in the operating performance points
(OPP) framework and clean it up somewhat (Viresh Kumar).
- Fix a CONFIG dependency in the hibernation core and clean it up
slightly (Balbir Singh, Arvind Yadav, BaoJun Luo).
- Add rk3228 support to the rockchip-io adaptive voltage scaling
(AVS) driver (David Wu).
- Fix an incorrect bit shift operation in the RAPL power capping
driver (Adam Lessnau).
- Add support for the EPP field in the HWP (hardware managed
P-states) control register, HWP.EPP, to the x86_energy_perf_policy
tool and update msr-index.h with HWP.EPP values (Len Brown).
- Fix some minor issues in the turbostat tool (Len Brown).
- Add support for AMD family 0x17 CPUs to the cpupower tool and fix
a minor issue in it (Sherry Hurwitz).
- Assorted cleanups, mostly related to the constification of some
data structures (Arvind Yadav, Joe Perches, Kees Cook, Krzysztof
Kozlowski).
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Merge tag 'pm-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"The big ticket items here are the rework of suspend-to-idle in order
to add proper support for power button wakeup from it on recent Dell
laptops and the rework of interfaces exporting the current CPU
frequency on x86.
In addition to that, support for a few new pieces of hardware is
added, the PCI/ACPI device wakeup infrastructure is simplified
significantly and the wakeup IRQ framework is fixed to unbreak the IRQ
bus locking infrastructure.
Also, there are some functional improvements for intel_pstate, tools
updates and small fixes and cleanups all over.
Specifics:
- Rework suspend-to-idle to allow it to take wakeup events signaled
by the EC into account on ACPI-based platforms in order to properly
support power button wakeup from suspend-to-idle on recent Dell
laptops (Rafael Wysocki).
That includes the core suspend-to-idle code rework, support for the
Low Power S0 _DSM interface, and support for the ACPI INT0002
Virtual GPIO device from Hans de Goede (required for USB keyboard
wakeup from suspend-to-idle to work on some machines).
- Stop trying to export the current CPU frequency via /proc/cpuinfo
on x86 as that is inaccurate and confusing (Len Brown).
- Rework the way in which the current CPU frequency is exported by
the kernel (over the cpufreq sysfs interface) on x86 systems with
the APERF and MPERF registers by always using values read from
these registers, when available, to compute the current frequency
regardless of which cpufreq driver is in use (Len Brown).
- Rework the PCI/ACPI device wakeup infrastructure to remove the
questionable and artificial distinction between "devices that can
wake up the system from sleep states" and "devices that can
generate wakeup signals in the working state" from it, which allows
the code to be simplified quite a bit (Rafael Wysocki).
- Fix the wakeup IRQ framework by making it use SRCU instead of RCU
which doesn't allow sleeping in the read-side critical sections,
but which in turn is expected to be allowed by the IRQ bus locking
infrastructure (Thomas Gleixner).
- Modify some computations in the intel_pstate driver to avoid
rounding errors resulting from them (Srinivas Pandruvada).
- Reduce the overhead of the intel_pstate driver in the HWP
(hardware-managed P-states) mode and when the "performance" P-state
selection algorithm is in use by making it avoid registering
scheduler callbacks in those cases (Len Brown).
- Rework the energy_performance_preference sysfs knob in intel_pstate
by changing the values that correspond to different symbolic hint
names used by it (Len Brown).
- Make it possible to use more than one cpuidle driver at the same
time on ARM (Daniel Lezcano).
- Make it possible to prevent the cpuidle menu governor from using
the 0 state by disabling it via sysfs (Nicholas Piggin).
- Add support for FFH (Fixed Functional Hardware) MWAIT in ACPI C1 on
AMD systems (Yazen Ghannam).
- Make the CPPC cpufreq driver take the lowest nonlinear performance
information into account (Prashanth Prakash).
- Add support for hi3660 to the cpufreq-dt driver, fix the imx6q
driver and clean up the sfi, exynos5440 and intel_pstate drivers
(Colin Ian King, Krzysztof Kozlowski, Octavian Purdila, Rafael
Wysocki, Tao Wang).
- Fix a few minor issues in the generic power domains (genpd)
framework and clean it up somewhat (Krzysztof Kozlowski, Mikko
Perttunen, Viresh Kumar).
- Fix a couple of minor issues in the operating performance points
(OPP) framework and clean it up somewhat (Viresh Kumar).
- Fix a CONFIG dependency in the hibernation core and clean it up
slightly (Balbir Singh, Arvind Yadav, BaoJun Luo).
- Add rk3228 support to the rockchip-io adaptive voltage scaling
(AVS) driver (David Wu).
- Fix an incorrect bit shift operation in the RAPL power capping
driver (Adam Lessnau).
- Add support for the EPP field in the HWP (hardware managed
P-states) control register, HWP.EPP, to the x86_energy_perf_policy
tool and update msr-index.h with HWP.EPP values (Len Brown).
- Fix some minor issues in the turbostat tool (Len Brown).
- Add support for AMD family 0x17 CPUs to the cpupower tool and fix a
minor issue in it (Sherry Hurwitz).
- Assorted cleanups, mostly related to the constification of some
data structures (Arvind Yadav, Joe Perches, Kees Cook, Krzysztof
Kozlowski)"
* tag 'pm-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (69 commits)
cpufreq: Update scaling_cur_freq documentation
cpufreq: intel_pstate: Clean up after performance governor changes
PM: hibernate: constify attribute_group structures.
cpuidle: menu: allow state 0 to be disabled
intel_idle: Use more common logging style
PM / Domains: Fix missing default_power_down_ok comment
PM / Domains: Fix unsafe iteration over modified list of domains
PM / Domains: Fix unsafe iteration over modified list of domain providers
PM / Domains: Fix unsafe iteration over modified list of device links
PM / Domains: Handle safely genpd_syscore_switch() call on non-genpd device
PM / Domains: Call driver's noirq callbacks
PM / core: Drop run_wake flag from struct dev_pm_info
PCI / PM: Simplify device wakeup settings code
PCI / PM: Drop pme_interrupt flag from struct pci_dev
ACPI / PM: Consolidate device wakeup settings code
ACPI / PM: Drop run_wake from struct acpi_device_wakeup_flags
PM / QoS: constify *_attribute_group.
PM / AVS: rockchip-io: add io selectors and supplies for rk3228
powercap/RAPL: prevent overridding bits outside of the mask
PM / sysfs: Constify attribute groups
...
Pull SMP hotplug updates from Thomas Gleixner:
"This update is primarily a cleanup of the CPU hotplug locking code.
The hotplug locking mechanism is an open coded RWSEM, which allows
recursive locking. The main problem with that is the recursive nature
as it evades the full lockdep coverage and hides potential deadlocks.
The rework replaces the open coded RWSEM with a percpu RWSEM and
establishes full lockdep coverage that way.
The bulk of the changes fix up recursive locking issues and address
the now fully reported potential deadlocks all over the place. Some of
these deadlocks have been observed in the RT tree, but on mainline the
probability was low enough to hide them away."
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
cpu/hotplug: Constify attribute_group structures
powerpc: Only obtain cpu_hotplug_lock if called by rtasd
ARM/hw_breakpoint: Fix possible recursive locking for arch_hw_breakpoint_init
cpu/hotplug: Remove unused check_for_tasks() function
perf/core: Don't release cred_guard_mutex if not taken
cpuhotplug: Link lock stacks for hotplug callbacks
acpi/processor: Prevent cpu hotplug deadlock
sched: Provide is_percpu_thread() helper
cpu/hotplug: Convert hotplug locking to percpu rwsem
s390: Prevent hotplug rwsem recursion
arm: Prevent hotplug rwsem recursion
arm64: Prevent cpu hotplug rwsem recursion
kprobes: Cure hotplug lock ordering issues
jump_label: Reorder hotplug lock and jump_label_lock
perf/tracing/cpuhotplug: Fix locking order
ACPI/processor: Use cpu_hotplug_disable() instead of get_online_cpus()
PCI: Replace the racy recursion prevention
PCI: Use cpu_hotplug_disable() instead of get_online_cpus()
perf/x86/intel: Drop get_online_cpus() in intel_snb_check_microcode()
x86/perf: Drop EXPORT of perf_check_microcode
...
The goal of this change is to give users a uniform and meaningful
result when they read /sys/...cpufreq/scaling_cur_freq
on modern x86 hardware, as compared to what they get today.
Modern x86 processors include the hardware needed
to accurately calculate frequency over an interval --
APERF, MPERF, and the TSC.
Here we provide an x86 routine to make this calculation
on supported hardware, and use it in preference to any
driver driver-specific cpufreq_driver.get() routine.
MHz is computed like so:
MHz = base_MHz * delta_APERF / delta_MPERF
MHz is the average frequency of the busy processor
over a measurement interval. The interval is
defined to be the time between successive invocations
of aperfmperf_khz_on_cpu(), which are expected to to
happen on-demand when users read sysfs attribute
cpufreq/scaling_cur_freq.
As with previous methods of calculating MHz,
idle time is excluded.
base_MHz above is from TSC calibration global "cpu_khz".
This x86 native method to calculate MHz returns a meaningful result
no matter if P-states are controlled by hardware or firmware
and/or if the Linux cpufreq sub-system is or is-not installed.
When this routine is invoked more frequently, the measurement
interval becomes shorter. However, the code limits re-computation
to 10ms intervals so that average frequency remains meaningful.
Discerning users are encouraged to take advantage of
the turbostat(8) utility, which can gracefully handle
concurrent measurement intervals of arbitrary length.
Signed-off-by: Len Brown <len.brown@intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
For a driver that does not set the CPUFREQ_STICKY flag, if all of the
->init() calls fail, cpufreq_register_driver() should return an error.
This will prevent the driver from loading.
Fixes: ce1bcfe94d (cpufreq: check cpufreq_policy_list instead of scanning policies for all CPUs)
Cc: 4.0+ <stable@vger.kernel.org> # 4.0+
Signed-off-by: David Arcari <darcari@redhat.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq holds get_online_cpus() while invoking cpuhp_setup_state_nocalls()
to make subsys_interface_register() and the registration of hotplug calls
atomic versus cpu hotplug.
cpuhp_setup_state_nocalls() invokes get_online_cpus() as well. This is
correct, but prevents the conversion of the hotplug locking to a percpu
rwsem.
Use cpuhp_setup/remove_state_nocalls_cpuslocked() to avoid the nested
call. Convert *_online_cpus() to the new interfaces while at it.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linux-pm@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170524081547.731628408@linutronix.de
There is a report that after commit 27622b061e ("cpufreq: Convert
to hotplug state machine"), the normal CPU offline/online cycle
fails on some platforms.
According to the ftrace result, this problem was triggered on
platforms using acpi-cpufreq as the default cpufreq driver,
and due to the lack of some ACPI freq method (eg. _PCT),
cpufreq_online() failed and returned a negative value, so the CPU
hotplug state machine rolled back the CPU online process. Actually,
from the user's perspective, the failure of cpufreq_online() should
not prevent that CPU from being brought up, although cpufreq might
not work on that CPU.
BTW, during system startup cpufreq_online() is not invoked via CPU
online but by the cpufreq device creation process, so the APs can be
brought up even though cpufreq_online() fails in that stage.
This patch ignores the return value of cpufreq_online/offline() and
lets the cpufreq framework deal with the failure. cpufreq_online()
itself will do a proper rollback in that case and if _PCT is missing,
the ACPI cpufreq driver will print a warning if the corresponding
debug options have been enabled.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=194581
Fixes: 27622b061e ("cpufreq: Convert to hotplug state machine")
Reported-and-tested-by: Tomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.9+ <stable@vger.kernel.org> # 4.9+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The cpufreq core only tries to create symbolic links from CPU
directories in sysfs to policy directories in cpufreq_add_dev(),
either when a given CPU is registered or when the cpufreq driver
is registered, whichever happens first. That is not sufficient,
however, because cpufreq_add_dev() may be called for an offline CPU
whose policy object has not been created yet and, quite obviously,
the symbolic cannot be added in that case.
Fix that by making cpufreq_online() attempt to add symbolic links to
policy objects for the CPUs in the related_cpus mask of every new
policy object created by it.
The cpufreq_driver_lock locking around the for_each_cpu() loop
in cpufreq_online() is dropped, because it is not necessary and the
code is somewhat simpler without it. Moreover, failures to create
a symbolic link will not be regarded as hard errors any more and
the CPUs without those links will not be taken offline automatically,
but that should not be problematic in practice.
Reported-and-tested-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 4.9+ <stable@vger.kernel.org> # 4.9+
On CPU online the cpufreq core restores the previous governor (or
the previous "policy" setting for ->setpolicy drivers), but it does
not restore the min/max limits at the same time, which is confusing,
inconsistent and real pain for users who set the limits and then
suspend/resume the system (using full suspend), in which case the
limits are reset on all CPUs except for the boot one.
Fix this by making cpufreq_online() restore the limits when an inactive
policy is brought online.
The commit log and patch are inspired from Rafael's earlier work.
Reported-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.3+ <stable@vger.kernel.org> # 4.3+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There is a missing newline in show_cpuinfo_cur_freq(), so add it,
but while at it clean that function up somewhat too.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: All applicable <stable@vger.kernel.org>
* pm-cpufreq:
cpufreq: intel_pstate: Do not reinit performance limits in ->setpolicy
cpufreq: intel_pstate: Fix intel_pstate_verify_policy()
cpufreq: intel_pstate: Fix global settings in active mode
cpufreq: Add the "cpufreq.off=1" cmdline option
cpufreq: intel_pstate: Avoid triggering cpu_frequency tracepoint unnecessarily
cpufreq: intel_pstate: Fix intel_cpufreq_verify_policy()
cpufreq: intel_pstate: Do not use performance_limits in passive mode
Add the "cpufreq.off=1" cmdline option.
At boot-time, this allows a user to request CONFIG_CPU_FREQ=n
behavior from a kernel built with CONFIG_CPU_FREQ=y.
This is analogous to the existing "cpuidle.off=1" option
and CONFIG_CPU_IDLE=y
This capability is valuable when we need to debug end-user
issues in the BIOS or in Linux. It is also convenient
for enabling comparisons, which may otherwise require a new kernel,
or help from BIOS SETUP, which may be buggy or unavailable.
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- Operating Performance Points (OPP) framework fixes, cleanups and
switch over from RCU-based synchronization to reference counting
using krefs (Viresh Kumar, Wei Yongjun, Dave Gerlach).
- cpufreq core cleanups and documentation updates (Viresh Kumar,
Rafael Wysocki).
- New cpufreq driver for Broadcom BMIPS SoCs (Markus Mayer).
- New cpufreq-dt sub-driver for TI SoCs requiring special handling,
like in the AM335x, AM437x, DRA7x, and AM57x families, along with
new DT bindings for it (Dave Gerlach, Paul Gortmaker).
- ARM64 SoCs support for the qoriq cpufreq driver (Tang Yuantian).
- intel_pstate driver updates including a new sysfs knob to control
the driver's operation mode and fixes related to the no_turbo
sysfs knob and the hardware-managed P-states feature support
(Rafael Wysocki, Srinivas Pandruvada).
- New interface to export ultra-turbo frequencies for the powernv
cpufreq driver (Shilpasri Bhat).
- Assorted fixes for cpufreq drivers (Arnd Bergmann, Dan Carpenter,
Wei Yongjun).
- devfreq core fixes, mostly related to the sysfs interface exported
by it (Chanwoo Choi, Chris Diamand).
- Updates of the exynos-bus and exynos-ppmu devfreq drivers (Chanwoo
Choi).
- Device PM QoS extension to support CPUs and support for per-CPU
wakeup (device resume) latency constraints in the cpuidle menu
governor (Alex Shi).
- Wakeup IRQs framework fixes (Grygorii Strashko).
- Generic power domains framework update including a fix to make
it handle asynchronous invocations of *noirq suspend/resume
callbacks correctly (Ulf Hansson, Geert Uytterhoeven).
- Assorted fixes and cleanups in the core suspend/hibernate code,
PM QoS framework and x86 ACPI idle support code (Corentin Labbe,
Geert Uytterhoeven, Geliang Tang, John Keeping, Nick Desaulniers).
- Update of the analyze_suspend.py script is updated to version 4.5
offering multiple improvements (Todd Brandt).
- New tool for intel_pstate diagnostics using the pstate_sample
tracepoint (Doug Smythies).
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Merge tag 'pm-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"The majority of changes go into the Operating Performance Points (OPP)
framework and cpufreq this time, followed by devfreq and some
scattered updates all over.
The OPP changes are mostly related to switching over from RCU-based
synchronization, that turned out to be overly complicated and
problematic, to reference counting using krefs.
In the cpufreq land there are core cleanups, documentation updates, a
new driver for Broadcom BMIPS SoCs, a new cpufreq-dt sub-driver for TI
SoCs that require special handling, ARM64 SoCs support for the qoriq
driver, intel_pstate updates, powernv driver update and assorted
fixes.
The devfreq changes are mostly fixes related to the sysfs interface
and some Exynos drivers updates.
Apart from that, the cpuidle menu governor will support per-CPU PM QoS
constraints for the wakeup latency now, some bugs in the wakeup IRQs
framework are fixed, the generic power domains framework should handle
asynchronous invocations of *noirq suspend/resume callbacks from now
on, the analyze_suspend.py script is updated and there is a new tool
for intel_pstate diagnostics.
Specifics:
- Operating Performance Points (OPP) framework fixes, cleanups and
switch over from RCU-based synchronization to reference counting
using krefs (Viresh Kumar, Wei Yongjun, Dave Gerlach)
- cpufreq core cleanups and documentation updates (Viresh Kumar,
Rafael Wysocki)
- New cpufreq driver for Broadcom BMIPS SoCs (Markus Mayer)
- New cpufreq-dt sub-driver for TI SoCs requiring special handling,
like in the AM335x, AM437x, DRA7x, and AM57x families, along with
new DT bindings for it (Dave Gerlach, Paul Gortmaker)
- ARM64 SoCs support for the qoriq cpufreq driver (Tang Yuantian)
- intel_pstate driver updates including a new sysfs knob to control
the driver's operation mode and fixes related to the no_turbo sysfs
knob and the hardware-managed P-states feature support (Rafael
Wysocki, Srinivas Pandruvada)
- New interface to export ultra-turbo frequencies for the powernv
cpufreq driver (Shilpasri Bhat)
- Assorted fixes for cpufreq drivers (Arnd Bergmann, Dan Carpenter,
Wei Yongjun)
- devfreq core fixes, mostly related to the sysfs interface exported
by it (Chanwoo Choi, Chris Diamand)
- Updates of the exynos-bus and exynos-ppmu devfreq drivers (Chanwoo
Choi)
- Device PM QoS extension to support CPUs and support for per-CPU
wakeup (device resume) latency constraints in the cpuidle menu
governor (Alex Shi)
- Wakeup IRQs framework fixes (Grygorii Strashko)
- Generic power domains framework update including a fix to make it
handle asynchronous invocations of *noirq suspend/resume callbacks
correctly (Ulf Hansson, Geert Uytterhoeven)
- Assorted fixes and cleanups in the core suspend/hibernate code, PM
QoS framework and x86 ACPI idle support code (Corentin Labbe, Geert
Uytterhoeven, Geliang Tang, John Keeping, Nick Desaulniers)
- Update of the analyze_suspend.py script is updated to version 4.5
offering multiple improvements (Todd Brandt)
- New tool for intel_pstate diagnostics using the pstate_sample
tracepoint (Doug Smythies)"
* tag 'pm-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (85 commits)
MAINTAINERS: cpufreq: add bmips-cpufreq.c
PM / QoS: Fix memory leak on resume_latency.notifiers
PM / Documentation: Spelling s/wrtie/write/
PM / sleep: Fix test_suspend after sleep state rework
cpufreq: CPPC: add ACPI_PROCESSOR dependency
cpufreq: make ti-cpufreq explicitly non-modular
cpufreq: Do not clear real_cpus mask on policy init
tools/power/x86: Debug utility for intel_pstate driver
AnalyzeSuspend: fix drag and zoom bug in javascript
PM / wakeirq: report a wakeup_event on dedicated wekup irq
PM / wakeirq: Fix spurious wake-up events for dedicated wakeirqs
PM / wakeirq: Enable dedicated wakeirq for suspend
cpufreq: dt: Don't use generic platdev driver for ti-cpufreq platforms
cpufreq: ti: Add cpufreq driver to determine available OPPs at runtime
Documentation: dt: add bindings for ti-cpufreq
PM / OPP: Expose _of_get_opp_desc_node as dev_pm_opp API
cpufreq: qoriq: Don't look at clock implementation details
cpufreq: qoriq: add ARM64 SoCs support
PM / Domains: Provide dummy governors if CONFIG_PM_GENERIC_DOMAINS=n
cpufreq: brcmstb-avs-cpufreq: remove unnecessary platform_set_drvdata()
...
If new_policy is set in cpufreq_online(), the policy object has just
been created and its real_cpus mask has been zeroed on allocation,
and the driver's ->init() callback should not touch it.
It doesn't need to be cleared again, so don't do that.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Those were added by:
commit fcd7af917a ("cpufreq: stats: handle cpufreq_unregister_driver()
and suspend/resume properly")
but aren't used anymore since:
commit 1aefc75b24 ("cpufreq: stats: Make the stats code non-modular").
Remove them. Also remove the redundant parameter to the respective
routines.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Kernel CPU stats are stored in cputime_t which is an architecture
defined type, and hence a bit opaque and requiring accessors and mutators
for any operation.
Converting them to nsecs simplifies the code and is one step toward
the removal of cputime_t in the core code.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1485832191-26889-4-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The return value of cpufreq_update_policy() is never used, so make
it void.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
There are two places in the cpufreq core in which low-level driver
callbacks may be invoked for an inactive cpufreq policy, which isn't
guaranteed to work in general. Both are due to possible races with
CPU offline.
First, in cpufreq_get(), the policy may become inactive after
the check against policy->cpus in cpufreq_cpu_get() and before
policy->rwsem is acquired, in which case using it going forward may
not be correct.
Second, an analogous situation is possible in cpufreq_update_policy().
Avoid using inactive policies by adding policy_is_inactive() checks
to the code in the above places.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Pull CPU hotplug updates from Thomas Gleixner:
"Yet another batch of cpu hotplug core updates and conversions:
- Provide core infrastructure for multi instance drivers so the
drivers do not have to keep custom lists.
- Convert custom lists to the new infrastructure. The block-mq custom
list conversion comes through the block tree and makes the diffstat
tip over to more lines removed than added.
- Handle unbalanced hotplug enable/disable calls more gracefully.
- Remove the obsolete CPU_STARTING/DYING notifier support.
- Convert another batch of notifier users.
The relayfs changes which conflicted with the conversion have been
shipped to me by Andrew.
The remaining lot is targeted for 4.10 so that we finally can remove
the rest of the notifiers"
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
cpufreq: Fix up conversion to hotplug state machine
blk/mq: Reserve hotplug states for block multiqueue
x86/apic/uv: Convert to hotplug state machine
s390/mm/pfault: Convert to hotplug state machine
mips/loongson/smp: Convert to hotplug state machine
mips/octeon/smp: Convert to hotplug state machine
fault-injection/cpu: Convert to hotplug state machine
padata: Convert to hotplug state machine
cpufreq: Convert to hotplug state machine
ACPI/processor: Convert to hotplug state machine
virtio scsi: Convert to hotplug state machine
oprofile/timer: Convert to hotplug state machine
block/softirq: Convert to hotplug state machine
lib/irq_poll: Convert to hotplug state machine
x86/microcode: Convert to hotplug state machine
sh/SH-X3 SMP: Convert to hotplug state machine
ia64/mca: Convert to hotplug state machine
ARM/OMAP/wakeupgen: Convert to hotplug state machine
ARM/shmobile: Convert to hotplug state machine
arm64/FP/SIMD: Convert to hotplug state machine
...
The function cpufreq_register_driver() returns zero on success and since
commit 27622b061e ("cpufreq: Convert to hotplug state machine")
erroneously a positive number. Due to the "if (x) assume_error" construct
all callers assumed an error and as a consequence the cpu freq kworker
crashes with a NULL pointer dereference.
Reset the return value back to zero in the success case.
Fixes: 27622b061e ("cpufreq: Convert to hotplug state machine")
Reported-by: Borislav Petkov <bp@alien8.de>
Reported-and-tested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: peterz@infradead.org
Cc: rjw@rjwysocki.net
Link: http://lkml.kernel.org/r/20160920145628.lp2bmq72ip3oiash@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If a cpufreq driver is registered very early in the boot stage (e.g.
registered from postcore_initcall()), then cpufreq core may generate
kernel warnings for it.
In this case, the CPUs are brought online, then the cpufreq driver is
registered, and then the CPU topology devices are registered. However,
by the time cpufreq_add_dev() gets called, the cpu device isn't stored
in the per-cpu variable (cpu_sys_devices,) which is read by
get_cpu_device().
So the cpufreq core fails to get device for the CPU, for which
cpufreq_add_dev() was called in the first place and we will hit a
WARN_ON(!cpu_dev).
Even if we reuse the 'dev' parameter passed to cpufreq_add_dev() to
avoid that warning, there might be other CPUs online that share the
policy with the cpu for which cpufreq_add_dev() is called. Eventually
get_cpu_device() will return NULL for them as well, and we will hit the
same WARN_ON() again.
In order to fix these issues, change cpufreq core to create links to the
policy for a cpu only when cpufreq_add_dev() is called for that CPU.
Reuse the 'real_cpus' mask to track that as well.
Note that cpufreq_remove_dev() already handles removal of the links for
individual CPUs and cpufreq_add_dev() has aligned with that now.
Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since cpufreq_policy_alloc() doesn't use its dev variable for
anything useful, drop that variable from there along with the
NULL check against it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Export cpufreq_driver_resolve_freq() since governors may be compiled as
modules.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Steve Muckle <smuckle@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The handlers provided by cpufreq core are sufficient for resolving the
frequency for drivers providing ->target_index(), as the core already
has the frequency table and so ->resolve_freq() isn't required for such
platforms.
This patch disallows drivers with ->target_index() callback to use the
->resolve_freq() callback.
Also, it fixes a potential kernel crash for drivers providing ->target()
but no ->resolve_freq().
Fixes: e3c0623608 "cpufreq: add cpufreq_driver_resolve_freq()"
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cpufreq governors may need to know what a particular target frequency
maps to in the driver without necessarily wanting to set the frequency.
Support this operation via a new cpufreq API,
cpufreq_driver_resolve_freq(). This API returns the lowest driver
frequency equal or greater than the target frequency
(CPUFREQ_RELATION_L), subject to any policy (min/max) or driver
limitations. The mapping is also cached in the policy so that a
subsequent fast_switch operation can avoid repeating the same lookup.
The API will call a new cpufreq driver callback, resolve_freq(), if it
has been registered by the driver. Otherwise the frequency is resolved
via cpufreq_frequency_table_target(). Rather than require ->target()
style drivers to provide a resolve_freq() callback it is left to the
caller to ensure that the driver implements this callback if necessary
to use cpufreq_driver_resolve_freq().
Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Steve Muckle <smuckle@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Both callers of cpufreq_update_current_freq(), cpufreq_update_policy()
and cpufreq_start_governor(), check cpufreq_suspended before calling
that function, so drop the redundant cpufreq_suspended check from it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
CPU notifications from the firmware coming in when cpufreq is
suspended cause cpufreq_update_current_freq() to return 0 which
triggers the WARN_ON() in cpufreq_update_policy() for no reason.
Avoid that by checking cpufreq_suspended before calling
cpufreq_update_current_freq().
Fixes: c9d9c929e6 (cpufreq: Abort cpufreq_update_current_freq() for cpufreq_suspended set)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.6+ <stable@vger.kernel.org> # 4.6+
This routine can't fail unless the frequency table is invalid and
doesn't contain any valid entries.
Make it return the index and WARN() in case it is used for an invalid
table.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
It is already present as part of the policy and so no need to pass it
from the caller. Also, 'freq_table' is guaranteed to be valid in this
function and so no need to check it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The policy already has this pointer set, use it instead.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Most of the callers of cpufreq_frequency_get_table() already have the
pointer to a valid 'policy' structure and they don't really need to go
through the per-cpu variable first and then a check to validate the
frequency, in order to find the freq-table for the policy.
Directly use the policy->freq_table field instead for them.
Only one user of that API is left after above changes, cpu_cooling.c and
it accesses the freq_table in a racy way as the policy can get freed in
between.
Fix it by using cpufreq_cpu_get() properly.
Since there are no more users of cpufreq_frequency_get_table() left, get
rid of it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Javi Merino <javi.merino@arm.com> (cpu_cooling.c)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The modularity of cpufreq_stats is quite problematic.
First off, the usage of policy notifiers for the initialization
and cleanup in the cpufreq_stats module is inherently racy with
respect to CPU offline/online and the initialization and cleanup
of the cpufreq driver.
Second, fast frequency switching (used by the schedutil governor)
cannot be enabled if any transition notifiers are registered, so
if the cpufreq_stats module (that registers a transition notifier
for updating transition statistics) is loaded, the schedutil governor
cannot use fast frequency switching.
On the other hand, allowing cpufreq_stats to be built as a module
doesn't really add much value. Arguably, there's not much reason
for that code to be modular at all.
For the above reasons, make the cpufreq stats code non-modular,
modify the core to invoke functions provided by that code directly
and drop the notifiers from it.
Make the stats sysfs attributes appear empty if fast frequency
switching is enabled as the statistics will not be updated in that
case anyway (and returning -EBUSY from those attributes breaks
powertop).
While at it, clean up Kconfig help for the CPU_FREQ_STAT and
CPU_FREQ_STAT_DETAILS options.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Use clamp_val() instead of open coding it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The sequence got a bit wrong as we are sending CPUFREQ_START
notifications even before we have sent CPUFREQ_CREATE_POLICY.
Fix it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The 'initialized' field in struct cpufreq_governor is only used by
the conservative governor (as a usage counter) and the way that
happens is far from straightforward and arguably incorrect.
Namely, the value of 'initialized' is checked by
cpufreq_dbs_governor_init() and cpufreq_dbs_governor_exit() and
the results of those checks are passed (as the second argument) to
the ->init() and ->exit() callbacks in struct dbs_governor. Those
callbacks are only implemented by the ondemand and conservative
governors and ondemand doesn't use their second argument at all.
In turn, the conservative governor uses it to decide whether or not
to either register or unregister a transition notifier.
That whole mechanism is not only unnecessarily convoluted, but also
racy, because the 'initialized' field of struct cpufreq_governor is
updated in cpufreq_init_governor() and cpufreq_exit_governor() under
policy->rwsem which doesn't help if one of these functions is run
twice in parallel for different policies (which isn't impossible in
principle), for example.
Instead of it, add a proper usage counter to the conservative
governor and update it from cs_init() and cs_exit() which is
guaranteed to be non-racy, as those functions are only called
under gov_dbs_data_mutex which is global.
With that in place, drop the 'initialized' field from struct
cpufreq_governor as it is not used any more.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
The design of the cpufreq governor API is not very straightforward,
as struct cpufreq_governor provides only one callback to be invoked
from different code paths for different purposes. The purpose it is
invoked for is determined by its second "event" argument, causing it
to act as a "callback multiplexer" of sorts.
Unfortunately, that leads to extra complexity in governors, some of
which implement the ->governor() callback as a switch statement
that simply checks the event argument and invokes a separate function
to handle that specific event.
That extra complexity can be eliminated by replacing the all-purpose
->governor() callback with a family of callbacks to carry out specific
governor operations: initialization and exit, start and stop and policy
limits updates. That also turns out to reduce the code size too, so
do it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
The return value of clamp_val() has to be stored actually.
Fixes: b7898fda5b (cpufreq: Support for fast frequency switching)
Reported-by: Steve Muckle <steve.muckle@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
The cpufreq_governor() routine is used by the cpufreq core to invoke
the current governor's ->governor() callback with appropriate arguments
and do some housekeeping related to that. Unfortunately, the way it
mixes different governor events in one code path makes it rather hard
to follow the code.
For this reason, split cpufreq_governor() into five simpler functions
that each will handle just one specific governor event and put all of
the code related to the given event into its own function.
This change is a prerequisite for a redesign of the cpufreq governor
API that will be done subsequently.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
It is not necessary to check the governor's max_transition_latency
attribute every time cpufreq_governor() runs, so check it only if
the event argument is CPUFREQ_GOV_POLICY_INIT.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
None of the cpufreq governors currently in the tree will ever fail
an invocation of the ->governor() callback with the event argument
equal to CPUFREQ_GOV_LIMITS (unless invoked with incorrect arguments
which doesn't matter anyway) and had it ever failed, the result of
it wouldn't have been very clean.
For this reason, rearrange the code in the core to ignore the return
value of cpufreq_governor() when called with event equal to
CPUFREQ_GOV_LIMITS.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
None of the cpufreq governors currently in the tree will ever fail
an invocation of the ->governor() callback with the event argument
equal to CPUFREQ_GOV_STOP (unless invoked with incorrect arguments
which doesn't matter anyway) and it is rather difficult to imagine
a valid reason for such a failure.
Accordingly, rearrange the code in the core to make it clear that
this call never fails.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
None of the cpufreq governors currently in the tree will ever fail
an invocation of the ->governor() callback with the event argument
equal to CPUFREQ_GOV_POLICY_EXIT (unless invoked with incorrect
arguments which doesn't matter anyway) and it wouldn't really
make sense to fail it, because the caller won't be able to handle
that failure in a meaningful way.
Accordingly, rearrange the code in the core to make it clear that
this call never fails.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
* pm-cpufreq-fixes:
intel_pstate: Fix intel_pstate_get()
cpufreq: intel_pstate: Fix HWP on boot CPU after system resume
cpufreq: st: enable selective initialization based on the platform
cpufreq: intel_pstate: Fix processing for turbo activation ratio
Commit 41cfd64cf4 "Update frequencies of policy->cpus only from
->set_policy()" changed the way the intel_pstate driver's ->set_policy
callback updates the HWP (hardware-managed P-states) settings.
A side effect of it is that if those settings are modified on the
boot CPU during system suspend and wakeup, they will never be
restored during subsequent system resume.
To address this problem, allow cpufreq drivers that don't provide
->target or ->target_index callbacks to use ->suspend and ->resume
callbacks and add a ->resume callback to intel_pstate to restore
the HWP settings on the CPUs that belong to the given policy.
Fixes: 41cfd64cf4 "Update frequencies of policy->cpus only from ->set_policy()"
Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Since governor operations are generally skipped if cpufreq_suspended
is set, cpufreq_start_governor() should do nothing in that case.
That function is called in the cpufreq_online() path, and may also
be called from cpufreq_offline() in some cases, which are invoked
by the nonboot CPUs disabing/enabling code during system suspend
to RAM and resume. That happens when all devices have been
suspended, so if the cpufreq driver relies on things like I2C to
get the current frequency, it may not be ready to do that then.
To prevent problems from happening for this reason, make
cpufreq_update_current_freq(), which is the only function invoked
by cpufreq_start_governor() that doesn't check cpufreq_suspended
already, return 0 upfront if cpufreq_suspended is set.
Fixes: 3bbf8fe3ae (cpufreq: Always update current frequency before startig governor)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reorganize the code in cpufreq_add_dev() to avoid using the ret
variable and reduce the indentation level in it.
No functional changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Merge two switch entries that do the same thing in
cpufreq_cpu_callback().
No functional changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Due to differences in the cpufreq core's handling of runtime CPU
offline and nonboot CPUs disabling during system suspend-to-RAM,
fast frequency switching gets disabled after a suspend-to-RAM and
resume cycle on all of the nonboot CPUs.
To prevent that from happening, move the invocation of
cpufreq_disable_fast_switch() from cpufreq_exit_governor() to
sugov_exit(), as the schedutil governor is the only user of fast
frequency switching today anyway.
That simply prevents cpufreq_disable_fast_switch() from being called
without invoking the ->governor callback for the CPUFREQ_GOV_POLICY_EXIT
event (which happens during system suspend now).
Fixes: b7898fda5b (cpufreq: Support for fast frequency switching)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Modify the ACPI cpufreq driver to provide a method for switching
CPU frequencies from interrupt context and update the cpufreq core
to support that method if available.
Introduce a new cpufreq driver callback, ->fast_switch, to be
invoked for frequency switching from interrupt context by (future)
governors supporting that feature via (new) helper function
cpufreq_driver_fast_switch().
Add two new policy flags, fast_switch_possible, to be set by the
cpufreq driver if fast frequency switching can be used for the
given policy and fast_switch_enabled, to be set by the governor
if it is going to use fast frequency switching for the given
policy. Also add a helper for setting the latter.
Since fast frequency switching is inherently incompatible with
cpufreq transition notifiers, make it possible to set the
fast_switch_enabled only if there are no transition notifiers
already registered and make the registration of new transition
notifiers fail if fast_switch_enabled is set for at least one
policy.
Implement the ->fast_switch callback in the ACPI cpufreq driver
and make it set fast_switch_possible during policy initialization
as appropriate.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Make policy->cur match the current frequency returned by the driver's
->get() callback before starting the governor in case they went out of
sync in the meantime and drop the piece of code attempting to
resync policy->cur with the real frequency of the boot CPU from
cpufreq_resume() as it serves no purpose any more (and it's racy and
super-ugly anyway).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Move the part of cpufreq_update_policy() that obtains the current
frequency from the driver and updates policy->cur if necessary to
a separate function, cpufreq_get_current_freq().
That should not introduce functional changes and subsequent change
set will need it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Starting a governor in cpufreq always follows the same pattern
involving two calls to cpufreq_governor(), one with the event
argument set to CPUFREQ_GOV_START and one with that argument set to
CPUFREQ_GOV_LIMITS.
Introduce cpufreq_start_governor() that will carry out those two
operations and make all places where governors are started use it.
That slightly modifies the behavior of cpufreq_set_policy() which
now also will go back to the old governor if the second call to
cpufreq_governor() (the one with event equal to CPUFREQ_GOV_LIMITS)
fails, but that really is how it should work in the first place.
Also cpufreq_resume() will now pring an error message if the
CPUFREQ_GOV_LIMITS call to cpufreq_governor() fails, but that
makes it follow cpufreq_add_policy_cpu() and cpufreq_offline()
in that respect.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
The function, cpufreq_quick_get, accesses the global 'cpufreq_driver' and
its fields without taking the associated lock, cpufreq_driver_lock.
Without the locking, nothing guarantees that 'cpufreq_driver' remains
consistent during the call. This patch fixes the issue by taking the lock
before accessing the data structure.
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Create cpufreq.c under kernel/sched/ and move the cpufreq code
related to the scheduler to that file and to sched.h.
Redefine cpufreq_update_util() as a static inline function to avoid
function calls at its call sites in the scheduler code (as suggested
by Peter Zijlstra).
Also move the definition of struct update_util_data and declaration
of cpufreq_set_update_util_data() from include/linux/cpufreq.h to
include/linux/sched.h.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Revert commit 3510fac454 (cpufreq: postfix policy directory with the
first CPU in related_cpus).
Earlier, the policy->kobj was added to the kobject core, before ->init()
callback was called for the cpufreq drivers. Which allowed those drivers
to add or remove, driver dependent, sysfs files/directories to the same
kobj from their ->init() and ->exit() callbacks.
That isn't possible anymore after commit 3510fac454.
Now, there is no other clean alternative that people can adopt.
Its better to revert the earlier commit to allow cpufreq drivers to
create/remove sysfs files from ->init() and ->exit() callbacks.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Use the observation that cpufreq_update_util() is only called
by the scheduler with rq->lock held, so the callers of
cpufreq_set_update_util_data() can use synchronize_sched()
instead of synchronize_rcu() to wait for cpufreq_update_util()
to complete. Moreover, if they are updated to do that,
rcu_read_(un)lock() calls in cpufreq_update_util() might be
replaced with rcu_read_(un)lock_sched(), respectively, but
those aren't really necessary, because the scheduler calls
that function from RCU-sched read-side critical sections
already.
In addition to that, if cpufreq_set_update_util_data() checks
the func field in the struct update_util_data before setting
the per-CPU pointer to it, the data->func check may be dropped
from cpufreq_update_util() as well.
Make the above changes to reduce the overhead from
cpufreq_update_util() in the scheduler paths invoking it
and to make the cleanup after removing its callbacks less
heavy-weight somewhat.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
The entire sequence of events (like INIT/START or STOP/EXIT) for which
cpufreq_governor() is called, is guaranteed to be protected by
policy->rwsem now.
The additional checks that were added earlier (as we were forced to drop
policy->rwsem before calling cpufreq_governor() for EXIT event), aren't
required anymore.
Over that, they weren't sufficient really. They just take care of
START/STOP events, but not INIT/EXIT and the state machine was never
maintained properly by them.
Kill the unnecessary checks and policy->governor_enabled field.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The __ at the beginning of the routine aren't really necessary at all.
Rename it to cpufreq_governor() instead.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
handle_update() is declared at the top of the file as its user appear
before its definition. Relocate the routine to get rid of this.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We used to drop policy->rwsem just before calling __cpufreq_governor()
in some cases earlier and so it was possible that __cpufreq_governor()
ran concurrently via separate threads for the same policy.
In order to guarantee valid state transitions for governors,
'governor_enabled' was required to be protected using some locking
and cpufreq_governor_lock was added for that.
But now __cpufreq_governor() is always called under policy->rwsem,
and 'governor_enabled' is protected against races even without
cpufreq_governor_lock.
Get rid of the extra lock now.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Juri Lelli <juri.lelli@arm.com>
Tested-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
[ rjw : Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The cpufreq core code is not consistent with respect to invoking
__cpufreq_governor() under policy->rwsem.
Changing all code to always hold policy->rwsem around
__cpufreq_governor() invocations will allow us to remove
cpufreq_governor_lock that is used today because we can't
guarantee that __cpufreq_governor() isn't executed twice in
parallel for the same policy.
We should also ensure that policy->rwsem is held across governor
state changes.
For example, while adding a CPU to the policy in the CPU online path,
we need to stop the governor, change policy->cpus, start the governor
and then refresh its limits. The complete sequence must be guaranteed
to complete without interruptions by concurrent governor state
updates. That can be achieved by holding policy->rwsem around those
sequences of operations.
Also note that after this patch cpufreq_driver->stop_cpu() and
->exit() will get called under policy->rwsem which wasn't the case
earlier. That shouldn't have any side effects, though.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Juri Lelli <juri.lelli@arm.com>
Tested-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 1aee40ac9c (cpufreq: Invoke __cpufreq_remove_dev_finish()
after releasing cpu_hotplug.lock) split the cpufreq's CPU offline
routine in two pieces, one of them to be run with CPU offline/online
locked and the other to be called later. The reason for that split
was a possible deadlock scenario involving cpufreq sysfs attributes
and CPU offline.
However, the handling of CPU offline in cpufreq has changed since
then. Policy sysfs attributes are never removed during CPU offline,
so there's no need to worry about accessing them during CPU offline,
because that can't lead to any deadlocks now. Governor sysfs
attributes are still removed in __cpufreq_governor(_EXIT), but
there is a new kobject type for them now and its show/store
callbacks don't lock CPU offline/online (they don't need to do
that).
This means that the CPU offline code in cpufreq doesn't need to
be split any more, so combine cpufreq_offline_prepare() with
cpufreq_offline_finish().
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Changelog ]
Tested-by: Juri Lelli <juri.lelli@arm.com>
Tested-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Earlier, when the struct freq-attr was used to represent governor
attributes, the standard cpufreq show/store sysfs attribute callbacks
were applied to the governor tunable attributes and they always acquire
the policy->rwsem lock before carrying out the operation. That could
have resulted in an ABBA deadlock if governor tunable attributes are
removed under policy->rwsem while one of them is being accessed
concurrently (if sysfs attributes removal wins the race, it will wait
for the access to complete with policy->rwsem held while the attribute
callback will block on policy->rwsem indefinitely).
We attempted to address this issue by dropping policy->rwsem around
governor tunable attributes removal (that is, around invocations of the
->governor callback with the event arg equal to CPUFREQ_GOV_POLICY_EXIT)
in cpufreq_set_policy(), but that opened up race conditions that had not
been possible with policy->rwsem held all the time.
The previous commit, "cpufreq: governor: New sysfs show/store callbacks
for governor tunables", fixed the original ABBA deadlock by adding new
governor specific show/store callbacks.
We don't have to drop rwsem around invocations of governor event
CPUFREQ_GOV_POLICY_EXIT anymore, and original fix can be reverted now.
Fixes: 955ef48335 (cpufreq: Drop rwsem lock around CPUFREQ_GOV_POLICY_EXIT)
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reported-by: Juri Lelli <juri.lelli@arm.com>
Tested-by: Juri Lelli <juri.lelli@arm.com>
Tested-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Introduce a mechanism by which parts of the cpufreq subsystem
("setpolicy" drivers or the core) can register callbacks to be
executed from cpufreq_update_util() which is invoked by the
scheduler's update_load_avg() on CPU utilization changes.
This allows the "setpolicy" drivers to dispense with their timers
and do all of the computations they need and frequency/voltage
adjustments in the update_load_avg() code path, among other things.
The update_load_avg() changes were suggested by Peter Zijlstra.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Drop a pointless label at a return statement from
__cpufreq_driver_target() and rearrange that function
to reduce the indentation level.
No intentional functional changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Eric Biggers <ebiggers3@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The comment has been incorrect since commit 4dea5806d3
("cpufreq: return EEXIST instead of EBUSY for second registering").
Signed-off-by: Eric Biggers <ebiggers3@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The show() and store() routines in the cpufreq core don't need to
check if the struct freq_attr they want to use really provides the
callbacks they need as expected (if that's not the case, it means
a bug in the code anyway), so change them to avoid doing that.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
The preprocessor magic used for setting the default cpufreq governor
(and for using the performance governor as a fallback one for that
matter) is really nasty, so replace it with __weak functions and
overrides.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Currently next_policy() explicitly checks if a policy is the last
policy in the cpufreq_policy_list. Use the standard list_is_last
primitive instead.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Notice that the boost_supported field in struct cpufreq_driver is
redundant, because the driver's ->set_boost callback may be left
unset if "boost" is not supported. Moreover, the only driver
populating the ->set_boost callback is acpi_cpufreq, so make it
avoid populating that callback if "boost" is not supported, rework
the core to check ->set_boost instead of boost_supported to
verify "boost" support and drop boost_supported which isn't
used any more.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
cpufreq_boost_supported() is not used outside of cpufreq.c, so make
it static.
While at it, refactor it as a one-liner (which it really is).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
For cpufreq drivers which use setpolicy interface, after offline->online
the policy is set to default. This can be reproduced by setting the
default policy of intel_pstate or longrun to ondemand and then change to
"performance". After offline and online, the setpolicy will be called with
the policy=ondemand.
For drivers using governors this condition is handled by storing
last_governor, during offline and restoring during online. The same should
be done for drivers using setpolicy interface. Storing last_policy during
offline and restoring during online.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Subsys interface's ->remove_dev() is called when the cpufreq driver is
unregistering or the CPU is getting physically removed. We keep removing
the cpuX/cpufreq link for all CPUs except the last one, which is a
mistake as all CPUs contain a link now.
Because of this, one CPU from each policy will still contain a link (to
an already removed policyX directory), after the cpufreq driver is
unregistered.
Fix that by removing the link first and then only see if the policy is
required to be freed. That will make sure that no links are left out.
Fixes: 96bdda61f5 ("cpufreq: create cpu/cpufreq/policyX directories")
Reported-and-tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The sysfs policy directory is postfixed currently with the CPU number
for which the policy was created, which isn't necessarily the first CPU
in related_cpus mask.
To make it more consistent and predictable, lets postfix the policy with
the first cpu in related-cpus mask.
Suggested-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The cpufreq sysfs interface had been a bit inconsistent as one of the
CPUs for a policy had a real directory within its sysfs 'cpuX' directory
and all other CPUs had links to it. That also made the code a bit
complex as we need to take care of moving the sysfs directory if the CPU
containing the real directory is getting physically hot-unplugged.
Solve this by creating 'policyX' directories (per-policy) in
/sys/devices/system/cpu/cpufreq/ directory, where X is the CPU for which
the policy was first created.
This also removes the need of keeping kobj_cpu and we can remove it now.
Suggested-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Saravana Kannan <skannan@codeaurora.org>
Acked-by: is more of a general agreement from the person that he is
Reviewed-by: is a more strict tag and implies that the reviewer has
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
They don't do anything special now, remove the unnecessary wrapper.
Reviewed-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Later patches will need to create policy specific directories in
/sys/devices/system/cpu/cpufreq/ directory and so the cpufreq directory
wouldn't be ever empty.
And so no fun creating/destroying it on need basis anymore. Create it
once on system boot.
Reviewed-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
->related_cpus is empty at this point of time and copying ->cpus to it
or orring ->related_cpus with ->cpus would result in the same value. But
cpumask_copy makes it rather clear.
Reviewed-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We just made sure policy->cpu is online and this check will always fail
as the policy is active. Drop it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When scaling_available_frequencies is read on an offlined cpu, then
either lockup or junk values are displayed. This is caused by
freed freq_table, which policy is using.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq_cpu_get() called by get_cur_freq_on_cpu() is overkill,
because the ->get() callback is always invoked in a context in
which all of the conditions checked by cpufreq_cpu_get() are
guaranteed to be satisfied.
Use cpufreq_cpu_get_raw() instead of it and drop the
corresponding cpufreq_cpu_put() from get_cur_freq_on_cpu().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
* pm-cpufreq:
intel_pstate: fix PCT_TO_HWP macro
intel_pstate: Fix user input of min/max to legal policy region
cpufreq-dt: add suspend frequency support
cpufreq: allow cpufreq_generic_suspend() to work without suspend frequency
cpufreq: Use __func__ to print function's name
cpufreq: staticize cpufreq_cpu_get_raw()
cpufreq: Add ARM_MT8173_CPUFREQ dependency on THERMAL
cpufreq: dt: Tolerance applies on both sides of target voltage
cpufreq: dt: Print error on failing to mark OPPs as shared
cpufreq: dt: Check OPP count before marking them shared
Some cpufreq drivers may set suspend frequency only for
selected setups but still would like to use the generic
suspend handler. Thus don't treat !policy->suspend_freq
condition as an incorrect one.
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Its better to use __func__ to print functions name instead of writing
the name in the print statement. This also has the advantage that a
change in function's name doesn't force us to change the print message
as well.
Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq_cpu_get_raw() isn't used by any external users, staticize it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- ACPICA update to upstream revision 20150818 including method
tracing extensions to allow more in-depth AML debugging in the
kernel and a number of assorted fixes and cleanups (Bob Moore,
Lv Zheng, Markus Elfring).
- ACPI sysfs code updates and a documentation update related to
AML method tracing (Lv Zheng).
- ACPI EC driver fix related to serialized evaluations of _Qxx
methods and ACPI tools updates allowing the EC userspace tool
to be built from the kernel source (Lv Zheng).
- ACPI processor driver updates preparing it for future
introduction of CPPC support and ACPI PCC mailbox driver
updates (Ashwin Chaugule).
- ACPI interrupts enumeration fix for a regression related
to the handling of IRQ attribute conflicts between MADT
and the ACPI namespace (Jiang Liu).
- Fixes related to ACPI device PM (Mika Westerberg, Srinidhi Kasagar).
- ACPI device registration code reorganization to separate the
sysfs-related code and bus type operations from the rest (Rafael
J Wysocki).
- Assorted cleanups in the ACPI core (Jarkko Nikula, Mathias Krause,
Andy Shevchenko, Rafael J Wysocki, Nicolas Iooss).
- ACPI cpufreq driver and ia64 cpufreq driver fixes and cleanups
(Pan Xinhui, Rafael J Wysocki).
- cpufreq core cleanups on top of the previous changes allowing it
to preseve its sysfs directories over system suspend/resume (Viresh
Kumar, Rafael J Wysocki, Sebastian Andrzej Siewior).
- cpufreq fixes and cleanups related to governors (Viresh Kumar).
- cpufreq updates (core and the cpufreq-dt driver) related to the
turbo/boost mode support (Viresh Kumar, Bartlomiej Zolnierkiewicz).
- New DT bindings for Operating Performance Points (OPP), support
for them in the OPP framework and in the cpufreq-dt driver plus
related OPP framework fixes and cleanups (Viresh Kumar).
- cpufreq powernv driver updates (Shilpasri G Bhat).
- New cpufreq driver for Mediatek MT8173 (Pi-Cheng Chen).
- Assorted cpufreq driver (speedstep-lib, sfi, integrator) cleanups
and fixes (Abhilash Jindal, Andrzej Hajda, Cristian Ardelean).
- intel_pstate driver updates including Skylake-S support, support
for enabling HW P-states per CPU and an additional vendor bypass
list entry (Kristen Carlson Accardi, Chen Yu, Ethan Zhao).
- cpuidle core fixes related to the handling of coupled idle states
(Xunlei Pang).
- intel_idle driver updates including Skylake Client support and
support for freeze-mode-specific idle states (Len Brown).
- Driver core updates related to power management (Andy Shevchenko,
Rafael J Wysocki).
- Generic power domains framework fixes and cleanups (Jon Hunter,
Geert Uytterhoeven, Rajendra Nayak, Ulf Hansson).
- Device PM QoS framework update to allow the latency tolerance
setting to be exposed to user space via sysfs (Mika Westerberg).
- devfreq support for PPMUv2 in Exynos5433 and a fix for an incorrect
exynos-ppmu DT binding (Chanwoo Choi, Javier Martinez Canillas).
- System sleep support updates (Alan Stern, Len Brown, SungEun Kim).
- rockchip-io AVS support updates (Heiko Stuebner).
- PM core clocks support fixup (Colin Ian King).
- Power capping RAPL driver update including support for Skylake H/S
and Broadwell-H (Radivoje Jovanovic, Seiichi Ikarashi).
- Generic device properties framework fixes related to the handling
of static (driver-provided) property sets (Andy Shevchenko).
- turbostat and cpupower updates (Len Brown, Shilpasri G Bhat,
Shreyas B Prabhu).
/
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Merge tag 'pm+acpi-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management and ACPI updates from Rafael Wysocki:
"From the number of commits perspective, the biggest items are ACPICA
and cpufreq changes with the latter taking the lead (over 50 commits).
On the cpufreq front, there are many cleanups and minor fixes in the
core and governors, driver updates etc. We also have a new cpufreq
driver for Mediatek MT8173 chips.
ACPICA mostly updates its debug infrastructure and adds a number of
fixes and cleanups for a good measure.
The Operating Performance Points (OPP) framework is updated with new
DT bindings and support for them among other things.
We have a few updates of the generic power domains framework and a
reorganization of the ACPI device enumeration code and bus type
operations.
And a lot of fixes and cleanups all over.
Included is one branch from the MFD tree as it contains some
PM-related driver core and ACPI PM changes a few other commits are
based on.
Specifics:
- ACPICA update to upstream revision 20150818 including method
tracing extensions to allow more in-depth AML debugging in the
kernel and a number of assorted fixes and cleanups (Bob Moore, Lv
Zheng, Markus Elfring).
- ACPI sysfs code updates and a documentation update related to AML
method tracing (Lv Zheng).
- ACPI EC driver fix related to serialized evaluations of _Qxx
methods and ACPI tools updates allowing the EC userspace tool to be
built from the kernel source (Lv Zheng).
- ACPI processor driver updates preparing it for future introduction
of CPPC support and ACPI PCC mailbox driver updates (Ashwin
Chaugule).
- ACPI interrupts enumeration fix for a regression related to the
handling of IRQ attribute conflicts between MADT and the ACPI
namespace (Jiang Liu).
- Fixes related to ACPI device PM (Mika Westerberg, Srinidhi
Kasagar).
- ACPI device registration code reorganization to separate the
sysfs-related code and bus type operations from the rest (Rafael J
Wysocki).
- Assorted cleanups in the ACPI core (Jarkko Nikula, Mathias Krause,
Andy Shevchenko, Rafael J Wysocki, Nicolas Iooss).
- ACPI cpufreq driver and ia64 cpufreq driver fixes and cleanups (Pan
Xinhui, Rafael J Wysocki).
- cpufreq core cleanups on top of the previous changes allowing it to
preseve its sysfs directories over system suspend/resume (Viresh
Kumar, Rafael J Wysocki, Sebastian Andrzej Siewior).
- cpufreq fixes and cleanups related to governors (Viresh Kumar).
- cpufreq updates (core and the cpufreq-dt driver) related to the
turbo/boost mode support (Viresh Kumar, Bartlomiej Zolnierkiewicz).
- New DT bindings for Operating Performance Points (OPP), support for
them in the OPP framework and in the cpufreq-dt driver plus related
OPP framework fixes and cleanups (Viresh Kumar).
- cpufreq powernv driver updates (Shilpasri G Bhat).
- New cpufreq driver for Mediatek MT8173 (Pi-Cheng Chen).
- Assorted cpufreq driver (speedstep-lib, sfi, integrator) cleanups
and fixes (Abhilash Jindal, Andrzej Hajda, Cristian Ardelean).
- intel_pstate driver updates including Skylake-S support, support
for enabling HW P-states per CPU and an additional vendor bypass
list entry (Kristen Carlson Accardi, Chen Yu, Ethan Zhao).
- cpuidle core fixes related to the handling of coupled idle states
(Xunlei Pang).
- intel_idle driver updates including Skylake Client support and
support for freeze-mode-specific idle states (Len Brown).
- Driver core updates related to power management (Andy Shevchenko,
Rafael J Wysocki).
- Generic power domains framework fixes and cleanups (Jon Hunter,
Geert Uytterhoeven, Rajendra Nayak, Ulf Hansson).
- Device PM QoS framework update to allow the latency tolerance
setting to be exposed to user space via sysfs (Mika Westerberg).
- devfreq support for PPMUv2 in Exynos5433 and a fix for an incorrect
exynos-ppmu DT binding (Chanwoo Choi, Javier Martinez Canillas).
- System sleep support updates (Alan Stern, Len Brown, SungEun Kim).
- rockchip-io AVS support updates (Heiko Stuebner).
- PM core clocks support fixup (Colin Ian King).
- Power capping RAPL driver update including support for Skylake H/S
and Broadwell-H (Radivoje Jovanovic, Seiichi Ikarashi).
- Generic device properties framework fixes related to the handling
of static (driver-provided) property sets (Andy Shevchenko).
- turbostat and cpupower updates (Len Brown, Shilpasri G Bhat,
Shreyas B Prabhu)"
* tag 'pm+acpi-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (180 commits)
cpufreq: speedstep-lib: Use monotonic clock
cpufreq: powernv: Increase the verbosity of OCC console messages
cpufreq: sfi: use kmemdup rather than duplicating its implementation
cpufreq: drop !cpufreq_driver check from cpufreq_parse_governor()
cpufreq: rename cpufreq_real_policy as cpufreq_user_policy
cpufreq: remove redundant 'policy' field from user_policy
cpufreq: remove redundant 'governor' field from user_policy
cpufreq: update user_policy.* on success
cpufreq: use memcpy() to copy policy
cpufreq: remove redundant CPUFREQ_INCOMPATIBLE notifier event
cpufreq: mediatek: Add MT8173 cpufreq driver
dt-bindings: mediatek: Add MT8173 CPU DVFS clock bindings
PM / Domains: Fix typo in description of genpd_dev_pm_detach()
PM / Domains: Remove unusable governor dummies
PM / Domains: Make pm_genpd_init() available to modules
PM / domains: Align column headers and data in pm_genpd_summary output
powercap / RAPL: disable the 2nd power limit properly
tools: cpupower: Fix error when running cpupower monitor
PM / OPP: Drop unlikely before IS_ERR(_OR_NULL)
PM / OPP: Fix static checker warning (broken 64bit big endian systems)
...
* pm-opp:
PM / OPP: Drop unlikely before IS_ERR(_OR_NULL)
PM / OPP: Fix static checker warning (broken 64bit big endian systems)
PM / OPP: Free resources and properly return error on failure
cpufreq-dt: make scaling_boost_freqs sysfs attr available when boost is enabled
cpufreq: dt: Add support for turbo/boost mode
cpufreq: dt: Add support for operating-points-v2 bindings
cpufreq: Allow drivers to enable boost support after registering driver
cpufreq: Update boost flag while initializing freq table from OPPs
PM / OPP: add dev_pm_opp_is_turbo() helper
PM / OPP: Add helpers for initializing CPU OPPs
PM / OPP: Add support for opp-suspend
PM / OPP: Add OPP sharing information to OPP library
PM / OPP: Add clock-latency-ns support
PM / OPP: Add support to parse "operating-points-v2" bindings
PM / OPP: Break _opp_add_dynamic() into smaller functions
PM / OPP: Allocate dev_opp from _add_device_opp()
PM / OPP: Create _remove_device_opp() for freeing dev_opp
PM / OPP: Relocate few routines
PM / OPP: Create a directory for opp bindings
PM / OPP: Update bindings to make opp-hz a 64 bit value
Driver is guaranteed to be present on a call to cpufreq_parse_governor()
and there is no need to check for !cpufreq_driver. Drop it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Its always same as policy->policy, and there is no need to keep another
copy of it. Remove it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Its always same as policy->governor, and there is no need to keep
another copy of it. Remove it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
'user_policy' caches properties of a policy that are set by userspace.
And these must be updated only if cpufreq core was successful in
updating them based on request from user space.
In store_scaling_governor(), we are updating user_policy.policy and
user_policy.governor even if cpufreq_set_policy() failed. That's
incorrect.
Fix this by updating user_policy.* only if we were successful in
updating the properties.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq_get_policy() is useful if the pointer to policy isn't available
in advance. But if it is available, then there is no need to call
cpufreq_get_policy(). Directly use memcpy() to copy the policy.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
What's being done from CPUFREQ_INCOMPATIBLE, can also be done with
CPUFREQ_ADJUST. There is nothing special with CPUFREQ_INCOMPATIBLE
notifier.
Kill CPUFREQ_INCOMPATIBLE and fix its usage sites.
This also updates the numbering of notifier events to remove holes.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Here is the new patches for the driver core / sysfs for 4.3-rc1.
Very small number of changes here, all the details are in the shortlog,
nothing major happening at all this kernel release, which is nice to
see.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the new patches for the driver core / sysfs for 4.3-rc1.
Very small number of changes here, all the details are in the
shortlog, nothing major happening at all this kernel release, which is
nice to see"
* tag 'driver-core-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
bus: subsys: update return type of ->remove_dev() to void
driver core: correct device's shutdown order
driver core: fix docbook for device_private.device
selftests: firmware: skip timeout checks for kernels without user mode helper
kernel, cpu: Remove bogus __ref annotations
cpu: Remove bogus __ref annotation of cpu_subsys_online()
firmware: fix wrong memory deallocation in fw_add_devm_name()
sysfs.txt: update show method notes about sprintf/snprintf/scnprintf usage
devres: fix devres_get()
In some cases it wouldn't be known at time of driver registration, if
the driver needs to support boost frequencies.
For example, while getting boost information from DT with opp-v2
bindings, we need to parse the bindings for all the CPUs to know if
turbo/boost OPPs are supported or not.
One way out to do that efficiently is to delay supporting boost mode
(i.e. creating /sys/devices/system/cpu/cpufreq/boost file), until the
time OPP bindings are parsed.
At that point, the driver can enable boost support. This can be done at
->init(), where the frequency table is created.
To do that, the driver requires few APIs from cpufreq core that let him
do this. This patch provides these APIs.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Its return value is not used by the subsys core and nothing meaningful
can be done with it, even if we want to use it. The subsys device is
anyway getting removed.
Update prototype of ->remove_dev() to make its return type as void. Fix
all usage sites as well.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This check was originally added by commit 9c9a43ed27 ("[CPUFREQ]
return error when failing to set minfreq").It attempt to return an error
on obviously incorrect limits when we echo xxx >.../scaling_max,min_freq
Actually we just need check if new_policy->min > new_policy->max.
Because at least one of max/min is copied from cpufreq_get_policy().
For example, when we echo xxx > .../scaling_min_freq, new_policy is
copied from policy in cpufreq_get_policy. new_policy->max is same with
policy->max. new_policy->min is set to a new value.
Let me explain it in deduction method, first statement in if ():
new_policy->min > policy->max
policy->max == new_policy->max
==> new_policy->min > new_policy->max
second statement in if():
new_policy->max < policy->min
policy->max < policy->min
==>new_policy->min > new_policy->max (induction method)
So we have proved that we only need check if new_policy->min >
new_policy->max.
After apply this patch, we can also modify ->min and ->max at same time
if new freq range is very much different from current freq range. For
example, if current freq range is 480000-960000, then we want to set
this range to 1120000-2240000, we would fail in the past because
new_policy->min > policy->max. As long as the cpufreq range is valid, we
has no reason to reject the user. So correct the check to avoid such
case.
Signed-off-by: Pan Xinhui <xinhuix.pan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
