Add __cpuidle_device_init() for initializing the cpuidle_device
structure.
[rjw: Changelog]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
To reduce code duplication related to the unregistration of cpuidle
devices, introduce __cpuidle_unregister_device() and move all of the
unregistration code to that function.
[rjw: Changelog]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The cpuidle sysfs code is designed to have a single instance of per
CPU cpuidle directory. It is not possible to remove the sysfs entry
and create it again. This is not a problem with the current code but
future changes will add CPU hotplug support to enable/disable the
device, so it will need to remove the sysfs entry like other
subsystems do. That won't be possible without this change, because
the kobj is a static object which can't be reused for
kobj_init_and_add().
Add cpuidle_device_kobj to be allocated dynamically when
adding/removing a sysfs entry which is consistent with the other
cpuidle's sysfs entries.
An added benefit is that the sysfs code is now more self-contained
and the includes needed for sysfs can be moved from cpuidle.h
directly into sysfs.c so as to reduce the total number of headers
dragged along with cpuidle.h.
[rjw: Changelog]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Fix white space in the cpuidle code to follow the rules described in
CodingStyle.
No changes in behavior should result from this.
[rjw: Changelog]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We previously changed the ordering of the cpuidle framework
initialization so that the governors are registered before the
drivers which can register their devices right from the start.
Now, we can safely remove the __cpuidle_register_device() call hack
in cpuidle_enable_device() and check if the driver has been
registered before enabling it. Then, cpuidle_register_device() can
consistently check the cpuidle_enable_device() return value when
enabling the device.
[rjw: Changelog]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq governors are defined as modules in the code, but the Kconfig
options do not allow them to be built as modules. This is not really
a problem, but the cpuidle init ordering is: the cpuidle init
functions (framework and driver) and then the governors. That leads
to some weirdness in the cpuidle framework.
Namely, cpuidle_register_device() calls cpuidle_enable_device() which
fails at the first attempt, because governors have not been registered
yet. When a governor is registered, the framework calls
cpuidle_enable_device() again which runs __cpuidle_register_device()
only then. Of course, for that to work, the cpuidle_enable_device()
return value has to be ignored by cpuidle_register_device().
Instead of having this cyclic call graph and relying on a positive
side effects of the hackish back and forth cpuidle_enable_device()
calls it is better to fix the cpuidle init ordering.
To that end, replace the module init code with postcore_initcall()
so we have:
* cpuidle framework : core_initcall
* cpuidle governors : postcore_initcall
* cpuidle drivers : device_initcall
and remove the corresponding module exit code as it is dead anyway
(governors can't be built as modules).
[rjw: Changelog]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- Hotplug changes allowing device hot-removal operations to fail
gracefully (instead of crashing the kernel) if they cannot be
carried out completely. From Rafael J Wysocki and Toshi Kani.
- Freezer update from Colin Cross and Mandeep Singh Baines targeted
at making the freezing of tasks a bit less heavy weight operation.
- cpufreq resume fix from Srivatsa S Bhat for a regression introduced
during the 3.10 cycle causing some cpufreq sysfs attributes to
return wrong values to user space after resume.
- New freqdomain_cpus sysfs attribute for the acpi-cpufreq driver to
provide information previously available via related_cpus from
Lan Tianyu.
- cpufreq fixes and cleanups from Viresh Kumar, Jacob Shin,
Heiko Stübner, Xiaoguang Chen, Ezequiel Garcia, Arnd Bergmann, and
Tang Yuantian.
- Fix for an ACPICA regression causing suspend/resume issues to
appear on some systems introduced during the 3.4 development cycle
from Lv Zheng.
- ACPICA fixes and cleanups from Bob Moore, Tomasz Nowicki, Lv Zheng,
Chao Guan, and Zhang Rui.
- New cupidle driver for Xilinx Zynq processors from Michal Simek.
- cpuidle fixes and cleanups from Daniel Lezcano.
- Changes to make suspend/resume work correctly in Xen guests from
Konrad Rzeszutek Wilk.
- ACPI device power management fixes and cleanups from Fengguang Wu
and Rafael J Wysocki.
- ACPI documentation updates from Lv Zheng, Aaron Lu and Hanjun Guo.
- Fix for the IA-64 issue that was the reason for reverting commit
9f29ab1 and updates of the ACPI scan code from Rafael J Wysocki.
- Mechanism for adding CMOS RTC address space handlers from Lan Tianyu
(to allow some EC-related breakage to be fixed on some systems).
- Spec-compliant implementation of acpi_os_get_timer() from
Mika Westerberg.
- Modification of do_acpi_find_child() to execute _STA in order to
to avoid situations in which a pointer to a disabled device object
is returned instead of an enabled one with the same _ADR value.
From Jeff Wu.
- Intel BayTrail PCH (Platform Controller Hub) support for the ACPI
Intel Low-Power Subsystems (LPSS) driver and modificaions of that
driver to work around a couple of known BIOS issues from
Mika Westerberg and Heikki Krogerus.
- EC driver fix from Vasiliy Kulikov to make it use get_user() and
put_user() instead of dereferencing user space pointers blindly.
- Assorted ACPI code cleanups from Bjorn Helgaas, Nicholas Mazzuca and
Toshi Kani.
- Modification of the "runtime idle" helper routine to take the return
values of the callbacks executed by it into account and to call
rpm_suspend() if they return 0, which allows some code bloat
reduction to be done, from Rafael J Wysocki and Alan Stern.
- New trace points for PM QoS from Sahara <keun-o.park@windriver.com>.
- PM QoS documentation update from Lan Tianyu.
- Assorted core PM code cleanups and changes from Bernie Thompson,
Bjorn Helgaas, Julius Werner, and Shuah Khan.
- New devfreq driver for the Exynos5-bus device from Abhilash Kesavan.
- Minor devfreq cleanups, fixes and MAINTAINERS update from
MyungJoo Ham, Abhilash Kesavan, Paul Bolle, Rajagopal Venkat, and
Wei Yongjun.
- OMAP Adaptive Voltage Scaling (AVS) SmartReflex voltage control
driver updates from Andrii Tseglytskyi and Nishanth Menon.
/
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Merge tag 'pm+acpi-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management and ACPI updates from Rafael Wysocki:
"This time the total number of ACPI commits is slightly greater than
the number of cpufreq commits, but Viresh Kumar (who works on cpufreq)
remains the most active patch submitter.
To me, the most significant change is the addition of offline/online
device operations to the driver core (with the Greg's blessing) and
the related modifications of the ACPI core hotplug code. Next are the
freezer updates from Colin Cross that should make the freezing of
tasks a bit less heavy weight.
We also have a couple of regression fixes, a number of fixes for
issues that have not been identified as regressions, two new drivers
and a bunch of cleanups all over.
Highlights:
- Hotplug changes to support graceful hot-removal failures.
It sometimes is necessary to fail device hot-removal operations
gracefully if they cannot be carried out completely. For example,
if memory from a memory module being hot-removed has been allocated
for the kernel's own use and cannot be moved elsewhere, it's
desirable to fail the hot-removal operation in a graceful way
rather than to crash the kernel, but currenty a success or a kernel
crash are the only possible outcomes of an attempted memory
hot-removal. Needless to say, that is not a very attractive
alternative and it had to be addressed.
However, in order to make it work for memory, I first had to make
it work for CPUs and for this purpose I needed to modify the ACPI
processor driver. It's been split into two parts, a resident one
handling the low-level initialization/cleanup and a modular one
playing the actual driver's role (but it binds to the CPU system
device objects rather than to the ACPI device objects representing
processors). That's been sort of like a live brain surgery on a
patient who's riding a bike.
So this is a little scary, but since we found and fixed a couple of
regressions it caused to happen during the early linux-next testing
(a month ago), nobody has complained.
As a bonus we remove some duplicated ACPI hotplug code, because the
ACPI-based CPU hotplug is now going to use the common ACPI hotplug
code.
- Lighter weight freezing of tasks.
These changes from Colin Cross and Mandeep Singh Baines are
targeted at making the freezing of tasks a bit less heavy weight
operation. They reduce the number of tasks woken up every time
during the freezing, by using the observation that the freezer
simply doesn't need to wake up some of them and wait for them all
to call refrigerator(). The time needed for the freezer to decide
to report a failure is reduced too.
Also reintroduced is the check causing a lockdep warining to
trigger when try_to_freeze() is called with locks held (which is
generally unsafe and shouldn't happen).
- cpufreq updates
First off, a commit from Srivatsa S Bhat fixes a resume regression
introduced during the 3.10 cycle causing some cpufreq sysfs
attributes to return wrong values to user space after resume. The
fix is kind of fresh, but also it's pretty obvious once Srivatsa
has identified the root cause.
Second, we have a new freqdomain_cpus sysfs attribute for the
acpi-cpufreq driver to provide information previously available via
related_cpus. From Lan Tianyu.
Finally, we fix a number of issues, mostly related to the
CPUFREQ_POSTCHANGE notifier and cpufreq Kconfig options and clean
up some code. The majority of changes from Viresh Kumar with bits
from Jacob Shin, Heiko Stübner, Xiaoguang Chen, Ezequiel Garcia,
Arnd Bergmann, and Tang Yuantian.
- ACPICA update
A usual bunch of updates from the ACPICA upstream.
During the 3.4 cycle we introduced support for ACPI 5 extended
sleep registers, but they are only supposed to be used if the
HW-reduced mode bit is set in the FADT flags and the code attempted
to use them without checking that bit. That caused suspend/resume
regressions to happen on some systems. Fix from Lv Zheng causes
those registers to be used only if the HW-reduced mode bit is set.
Apart from this some other ACPICA bugs are fixed and code cleanups
are made by Bob Moore, Tomasz Nowicki, Lv Zheng, Chao Guan, and
Zhang Rui.
- cpuidle updates
New driver for Xilinx Zynq processors is added by Michal Simek.
Multidriver support simplification, addition of some missing
kerneldoc comments and Kconfig-related fixes come from Daniel
Lezcano.
- ACPI power management updates
Changes to make suspend/resume work correctly in Xen guests from
Konrad Rzeszutek Wilk, sparse warning fix from Fengguang Wu and
cleanups and fixes of the ACPI device power state selection
routine.
- ACPI documentation updates
Some previously missing pieces of ACPI documentation are added by
Lv Zheng and Aaron Lu (hopefully, that will help people to
uderstand how the ACPI subsystem works) and one outdated doc is
updated by Hanjun Guo.
- Assorted ACPI updates
We finally nailed down the IA-64 issue that was the reason for
reverting commit 9f29ab11dd ("ACPI / scan: do not match drivers
against objects having scan handlers"), so we can fix it and move
the ACPI scan handler check added to the ACPI video driver back to
the core.
A mechanism for adding CMOS RTC address space handlers is
introduced by Lan Tianyu to allow some EC-related breakage to be
fixed on some systems.
A spec-compliant implementation of acpi_os_get_timer() is added by
Mika Westerberg.
The evaluation of _STA is added to do_acpi_find_child() to avoid
situations in which a pointer to a disabled device object is
returned instead of an enabled one with the same _ADR value. From
Jeff Wu.
Intel BayTrail PCH (Platform Controller Hub) support is added to
the ACPI driver for Intel Low-Power Subsystems (LPSS) and that
driver is modified to work around a couple of known BIOS issues.
Changes from Mika Westerberg and Heikki Krogerus.
The EC driver is fixed by Vasiliy Kulikov to use get_user() and
put_user() instead of dereferencing user space pointers blindly.
Code cleanups are made by Bjorn Helgaas, Nicholas Mazzuca and Toshi
Kani.
- Assorted power management updates
The "runtime idle" helper routine is changed to take the return
values of the callbacks executed by it into account and to call
rpm_suspend() if they return 0, which allows us to reduce the
overall code bloat a bit (by dropping some code that's not
necessary any more after that modification).
The runtime PM documentation is updated by Alan Stern (to reflect
the "runtime idle" behavior change).
New trace points for PM QoS are added by Sahara
(<keun-o.park@windriver.com>).
PM QoS documentation is updated by Lan Tianyu.
Code cleanups are made and minor issues are addressed by Bernie
Thompson, Bjorn Helgaas, Julius Werner, and Shuah Khan.
- devfreq updates
New driver for the Exynos5-bus device from Abhilash Kesavan.
Minor cleanups, fixes and MAINTAINERS update from MyungJoo Ham,
Abhilash Kesavan, Paul Bolle, Rajagopal Venkat, and Wei Yongjun.
- OMAP power management updates
Adaptive Voltage Scaling (AVS) SmartReflex voltage control driver
updates from Andrii Tseglytskyi and Nishanth Menon."
* tag 'pm+acpi-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (162 commits)
cpufreq: Fix cpufreq regression after suspend/resume
ACPI / PM: Fix possible NULL pointer deref in acpi_pm_device_sleep_state()
PM / Sleep: Warn about system time after resume with pm_trace
cpufreq: don't leave stale policy pointer in cdbs->cur_policy
acpi-cpufreq: Add new sysfs attribute freqdomain_cpus
cpufreq: make sure frequency transitions are serialized
ACPI: implement acpi_os_get_timer() according the spec
ACPI / EC: Add HP Folio 13 to ec_dmi_table in order to skip DSDT scan
ACPI: Add CMOS RTC Operation Region handler support
ACPI / processor: Drop unused variable from processor_perflib.c
cpufreq: tegra: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: s3c64xx: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: omap: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: imx6q: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: exynos: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: dbx500: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: davinci: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: arm-big-little: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: powernow-k8: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: pcc: call CPUFREQ_POSTCHANGE notfier in error cases
...
These changes are all to SoC-specific code, a total of 33 branches on
17 platforms were pulled into this. Like last time, Renesas sh-mobile
is now the platform with the most changes, followed by OMAP and EXYNOS.
Two new platforms, TI Keystone and Rockchips RK3xxx are added in
this branch, both containing almost no platform specific code at all,
since they are using generic subsystem interfaces for clocks, pinctrl,
interrupts etc. The device drivers are getting merged through the
respective subsystem maintainer trees.
One more SoC (u300) is now multiplatform capable and several others
(shmobile, exynos, msm, integrator, kirkwood, clps711x) are moving
towards that goal with this series but need more work.
Also noteworthy is the work on PCI here, which is traditionally part of
the SoC specific code. With the changes done by Thomas Petazzoni, we can
now more easily have PCI host controller drivers as loadable modules and
keep them separate from the platform code in drivers/pci/host. This has
already led to the discovery that three platforms (exynos, spear and imx)
are actually using an identical PCIe host controller and will be able
to share a driver once support for spear and imx is added.
Conflicts:
* asm/glue-proc.h has one CPU type getting added that conflicts
with another addition in 3.10-rc7
* Simple context changes in arch/arm/Makefile and arch/arm/Kconfig
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Merge tag 'soc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC specific changes from Arnd Bergmann:
"These changes are all to SoC-specific code, a total of 33 branches on
17 platforms were pulled into this. Like last time, Renesas sh-mobile
is now the platform with the most changes, followed by OMAP and
EXYNOS.
Two new platforms, TI Keystone and Rockchips RK3xxx are added in this
branch, both containing almost no platform specific code at all, since
they are using generic subsystem interfaces for clocks, pinctrl,
interrupts etc. The device drivers are getting merged through the
respective subsystem maintainer trees.
One more SoC (u300) is now multiplatform capable and several others
(shmobile, exynos, msm, integrator, kirkwood, clps711x) are moving
towards that goal with this series but need more work.
Also noteworthy is the work on PCI here, which is traditionally part
of the SoC specific code. With the changes done by Thomas Petazzoni,
we can now more easily have PCI host controller drivers as loadable
modules and keep them separate from the platform code in
drivers/pci/host. This has already led to the discovery that three
platforms (exynos, spear and imx) are actually using an identical PCIe
host controller and will be able to share a driver once support for
spear and imx is added."
* tag 'soc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (480 commits)
ARM: integrator: let pciv3 use mem/premem from device tree
ARM: integrator: set local side PCI addresses right
ARM: dts: Add pcie controller node for exynos5440-ssdk5440
ARM: dts: Add pcie controller node for Samsung EXYNOS5440 SoC
ARM: EXYNOS: Enable PCIe support for Exynos5440
pci: Add PCIe driver for Samsung Exynos
ARM: OMAP5: voltagedomain data: remove temporary OMAP4 voltage data
ARM: keystone: Move CPU bringup code to dedicated asm file
ARM: multiplatform: always pick one CPU type
ARM: imx: select syscon for IMX6SL
ARM: keystone: select ARM_ERRATA_798181 only for SMP
ARM: imx: Synertronixx scb9328 needs to select SOC_IMX1
ARM: OMAP2+: AM43x: resolve SMP related build error
dmaengine: edma: enable build for AM33XX
ARM: edma: Add EDMA crossbar event mux support
ARM: edma: Add DT and runtime PM support to the private EDMA API
dmaengine: edma: Add TI EDMA device tree binding
arm: add basic support for Rockchip RK3066a boards
arm: add debug uarts for rockchip rk29xx and rk3xxx series
arm: Add basic clocks for Rockchip rk3066a SoCs
...
Like other ARM specific drivers, this one requires ARM_CPU_SUSPEND,
as shown by this linker error:
drivers/built-in.o: In function `calxeda_pwrdown_idle':
drivers/cpuidle/cpuidle-calxeda.c:84: undefined reference to `cpu_suspend'
drivers/cpuidle/cpuidle-calxeda.c:86: undefined reference to `cpu_resume'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-pm@vger.kernel.org
Before commit d6f346f (cpuidle: improve governor Kconfig options),
the CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED option didn't depend on
CONFIG_CPU_IDLE but now it has been moved under the CPU_IDLE
menuconfig.
That raises the following warnings:
warning: (ARCH_OMAP4 && ARCH_TEGRA_2x_SOC) selects ARCH_NEEDS_CPU_IDLE_COUPLED
which has unmet direct dependencies (CPU_IDLE)
warning: (ARCH_OMAP4 && ARCH_TEGRA_2x_SOC) selects ARCH_NEEDS_CPU_IDLE_COUPLED
which has unmet direct dependencies (CPU_IDLE)
because the tegra2 and omap4 Kconfig files select this option
without checking if CPU_IDLE is set.
Fix that by moving ARCH_NEEDS_CPU_IDLE_COUPLED outside of CPU_IDLE.
[rjw: Changelog]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add kerneldoc (and other) comments to the cpuidle driver's framework
code.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit bf4d1b5 (cpuidle: support multiple drivers) introduced support
for using multiple cpuidle drivers at the same time. It added a
couple of new APIs to register the driver per CPU, but that led to
some unnecessary code complexity related to the kernel config options
deciding whether or not the multiple driver support is enabled. The
code has to work as it did before when the multiple driver support is
not enabled and the multiple driver support has to be compatible with
the previously existing API.
Remove the new API, not used by any driver in the tree yet (but
needed for the HMP cpuidle drivers that will be submitted soon), and
add a new cpumask pointer to the cpuidle driver structure that will
point to the mask of CPUs handled by the given driver. That will
allow the cpuidle_[un]register_driver() API to be used for the
multiple driver support along with the cpuidle_[un]register()
functions added recently.
[rjw: Changelog]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add cpuidle support for Xilinx Zynq.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Each governor is suitable for different kernel configurations: the menu
governor suits better for a tickless system, while the ladder governor fits
better for a periodic timer tick system.
The Kconfig does not allow to [un]select a governor, thus both are compiled in
the kernel but the init order makes the menu governor to be the last one to be
registered, so becoming the default. The only way to switch back to the ladder
governor is to enable the sysfs governor switch in the kernel command line.
Because it seems nobody complained about this, the menu governor is used by
default most of the time on the system, having both governors is not really
necessary on a tickless system but there isn't a config option to disable one
or another governor.
Create a submenu for cpuidle and add a label for each governor, so we can see
the option in the menu config and enable/disable it.
The governors will be enabled depending on the CONFIG_NO_HZ option:
- If CONFIG_NO_HZ is set, then the menu governor is selected and the ladder
governor is optional, defaulting to 'yes'
- If CONFIG_NO_HZ is not set, then the ladder governor is selected and the
menu governor is optional, defaulting to 'yes'
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Move the private set_auxcr/get_auxcr functions from
drivers/cpuidle/cpuidle-calxeda.c so they can be used across platforms.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Currently cpuidle drivers are spread across different archs.
As a result, there are several different paths for cpuidle patch
submissions: cpuidle core changes go through linux-pm, ARM driver
changes go to the arm-soc or SoC-specific trees, sh changes go
through the sh arch tree, pseries changes go through the PowerPC tree
and finally intel changes go through the Len's tree while ACPI idle
changes go through linux-pm.
That makes it difficult to consolidate code and to propagate
modifications from the cpuidle core to the different drivers.
Hopefully, a movement has started to put the majority of cpuidle
drivers under drivers/cpuidle like cpuidle-calxeda.c and
cpuidle-kirkwood.c.
Add a maintainer entry for cpuidle to MAINTAINERS to clarify the
situation and to indicate to new cpuidle driver authors that those
drivers should not go into arch-specific directories.
The upstreaming process is unchanged: Rafael takes patches for
merging into his tree, but with an Acked-by: tag from the driver's
maintainer, so indicate in the drivers' headers who maintains them.
The arrangement will be the same as for cpufreq.
[rjw: Changelog]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andrew Lunn <andrew@lunn.ch> #for kirkwood
Acked-by: Jason Cooper <jason@lakedaemon.net> #for kirkwood
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Fix comment format for the kernel doc script.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The usual scheme to initialize a cpuidle driver on a SMP is:
cpuidle_register_driver(drv);
for_each_possible_cpu(cpu) {
device = &per_cpu(cpuidle_dev, cpu);
cpuidle_register_device(device);
}
This code is duplicated in each cpuidle driver.
On UP systems, it is done this way:
cpuidle_register_driver(drv);
device = &per_cpu(cpuidle_dev, cpu);
cpuidle_register_device(device);
On UP, the macro 'for_each_cpu' does one iteration:
#define for_each_cpu(cpu, mask) \
for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
Hence, the initialization loop is the same for UP than SMP.
Beside, we saw different bugs / mis-initialization / return code unchecked in
the different drivers, the code is duplicated including bugs. After fixing all
these ones, it appears the initialization pattern is the same for everyone.
Please note, some drivers are doing dev->state_count = drv->state_count. This is
not necessary because it is done by the cpuidle_enable_device function in the
cpuidle framework. This is true, until you have the same states for all your
devices. Otherwise, the 'low level' API should be used instead with the specific
initialization for the driver.
Let's add a wrapper function doing this initialization with a cpumask parameter
for the coupled idle states and use it for all the drivers.
That will save a lot of LOC, consolidate the code, and the modifications in the
future could be done in a single place. Another benefit is the consolidation of
the cpuidle_device variable which is now in the cpuidle framework and no longer
spread accross the different arch specific drivers.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The en_core_tk_irqen flag is set in all the cpuidle driver which
means it is not necessary to specify this flag.
Remove the flag and the code related to it.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org> # for mach-omap2/*
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The commit 89878baa73f0f1c679355006bd8632e5d78f96c2 introduced
the CPUIDLE_FLAG_TIMER_STOP flag where we specify a specific idle
state stops the local timer.
Now use this flag to check at init time if one state will need
the broadcast timer and, in this case, setup the broadcast timer
framework. That prevents multiple code duplication in the drivers.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Convert all uses of devm_request_and_ioremap() to the newly introduced
devm_ioremap_resource() which provides more consistent error handling.
devm_ioremap_resource() provides its own error messages so all explicit
error messages can be removed from the failure code paths.
Signed-off-by: Silviu-Mihai Popescu <silviupopescu1990@gmail.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When the CPU_IDLE and the ARCH_KIRKWOOD options are set it is
pointless to define a new option CPU_IDLE_KIRKWOOD because it
is redundant.
The Makefile drivers directory contains a condition to compile
the cpuidle drivers:
obj-$(CONFIG_CPU_IDLE) += cpuidle/
Hence, if CPU_IDLE is not set we won't enter this directory.
This patch removes the useless Kconfig option and replaces the
condition in the Makefile by CONFIG_ARCH_KIRKWOOD.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When a cpu enters a deep idle state, the local timers are stopped and
the time framework falls back to the timer device used as a broadcast
timer.
The different cpuidle drivers are calling clockevents_notify ENTER/EXIT
when the idle state stops the local timer.
Add a new flag CPUIDLE_FLAG_TIMER_STOP which can be set by the cpuidle
drivers. If the flag is set, the cpuidle core code takes care of the
notification on behalf of the driver to avoid pointless code duplication.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This is a larger set of new functionality for the existing SoC families,
including:
* vt8500 gains support for new CPU cores, notably the Cortex-A9 based wm8850
* prima2 gains support for the "marco" SoC family, its SMP based cousin
* tegra gains support for the new Tegra4 (Tegra114) family
* socfpga now supports a newer version of the hardware including SMP
* i.mx31 and bcm2835 are now using DT probing for their clocks
* lots of updates for sh-mobile
* OMAP updates for clocks, power management and USB
* i.mx6q and tegra now support cpuidle
* kirkwood now supports PCIe hot plugging
* tegra clock support is updated
* tegra USB PHY probing gets implemented diffently
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Merge tag 'soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC-specific updates from Arnd Bergmann:
"This is a larger set of new functionality for the existing SoC
families, including:
- vt8500 gains support for new CPU cores, notably the Cortex-A9 based
wm8850
- prima2 gains support for the "marco" SoC family, its SMP based
cousin
- tegra gains support for the new Tegra4 (Tegra114) family
- socfpga now supports a newer version of the hardware including SMP
- i.mx31 and bcm2835 are now using DT probing for their clocks
- lots of updates for sh-mobile
- OMAP updates for clocks, power management and USB
- i.mx6q and tegra now support cpuidle
- kirkwood now supports PCIe hot plugging
- tegra clock support is updated
- tegra USB PHY probing gets implemented diffently"
* tag 'soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (148 commits)
ARM: prima2: remove duplicate v7_invalidate_l1
ARM: shmobile: r8a7779: Correct TMU clock support again
ARM: prima2: fix __init section for cpu hotplug
ARM: OMAP: Consolidate OMAP USB-HS platform data (part 3/3)
ARM: OMAP: Consolidate OMAP USB-HS platform data (part 1/3)
arm: socfpga: Add SMP support for actual socfpga harware
arm: Add v7_invalidate_l1 to cache-v7.S
arm: socfpga: Add entries to enable make dtbs socfpga
arm: socfpga: Add new device tree source for actual socfpga HW
ARM: tegra: sort Kconfig selects for Tegra114
ARM: tegra: enable ARCH_REQUIRE_GPIOLIB for Tegra114
ARM: tegra: Fix build error w/ ARCH_TEGRA_114_SOC w/o ARCH_TEGRA_3x_SOC
ARM: tegra: Fix build error for gic update
ARM: tegra: remove empty tegra_smp_init_cpus()
ARM: shmobile: Register ARM architected timer
ARM: MARCO: fix the build issue due to gic-vic-to-irqchip move
ARM: shmobile: r8a7779: Correct TMU clock support
ARM: mxs_defconfig: Select CONFIG_DEVTMPFS_MOUNT
ARM: mxs: decrease mxs_clockevent_device.min_delta_ns to 2 clock cycles
ARM: mxs: use apbx bus clock to drive the timers on timrotv2
...
Move the Kirkwood cpuidle driver out of arch/arm/mach-kirkwood and
into drivers/cpuidle. Convert the driver into a platform driver.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
The text in Documentation said it would be removed in 2.6.41;
the text in the Kconfig said removal in the 3.1 release. Either
way you look at it, we are well past both, so push it off a cliff.
Note that the POWER_CSTATE and the POWER_PSTATE are part of the
legacy tracing API. Remove all tracepoints which use these flags.
As can be seen from context, most already have a trace entry via
trace_cpu_idle anyways.
Also, the cpufreq/cpufreq.c PSTATE one is actually unpaired, as
compared to the CSTATE ones which all have a clear start/stop.
As part of this, the trace_power_frequency also becomes orphaned,
so it too is deleted.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We realized that the power usage field is never filled and when it
is filled for tegra, the power_specified flag is not set causing all
of these values to be reset when the driver is initialized with
set_power_state().
However, the power_specified flag can be simply removed under the
assumption that the states are always backward sorted, which is the
case with the current code.
This change allows the menu governor select function and the
cpuidle_play_dead() to be simplified. Moreover, the
set_power_states() function can removed as it does not make sense
any more.
Drop the power_specified flag from struct cpuidle_driver and make
the related changes as described above.
As a consequence, this also fixes the bug where on the dynamic
C-states system, the power fields are not initialized.
[rjw: Changelog]
References: https://bugzilla.kernel.org/show_bug.cgi?id=42870
References: https://bugzilla.kernel.org/show_bug.cgi?id=43349
References: https://lkml.org/lkml/2012/10/16/518
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit bf4d1b5ddb (cpuidle: support
multiple drivers) changed the number of initialized state kobjects
in cpuidle_add_state_sysfs() from device->state_count to
drv->state_count, but left device->state_count in
cpuidle_remove_state_sysfs(). The values of these two fields may be
different, in which case a NULL pointer dereference may happen in
cpuidle_remove_state_sysfs(), for example. Fix this problem by making
cpuidle_add_state_sysfs() use device->state_count too (which restores
the original behavior of it).
[rjw: Changelog]
Signed-off-by: Krzysztof Mazur <krzysiek@podlesie.net>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit bf4d1b5 (cpuidle: support multiple drivers) introduced
locking in cpuidle_get_cpu_driver(), which is used in the
idle_call() function.
This leads to a contention problem with a large number of CPUs,
because they all try to run the idle routine at the same time.
The lock can be safely removed because of how is used the cpuidle
API. Namely, cpuidle_register_driver() is called first, but the
cpuidle idle function is not entered before cpuidle_register_device()
is called, because the cpuidle device is not enabled then. Moreover,
cpuidle_unregister_driver(), which would reset the driver value to
NULL, is not called before cpuidle_unregister_device().
All of the cpuidle drivers use the API in the same way.
In general, a cleanup around the lock is necessary and a proper
refcounting mechanism should be used to ensure the consistency in the
API (for example, cpuidle_unregister_driver() should fail if the
driver's refcount is not 0). However, these modifications will require
some code reorganization and rewrite which will be too intrusive for
a fix.
For this reason, fix the contention problem introduced by commit
bf4d1b5 by simply removing the locking from cpuidle_get_cpu_driver(),
which restores the original behavior of that routine.
[rjw: Changelog.]
Reported-and-tested-by: Russ Anderson <rja@sgi.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ready_waiting_counts atomic variable is compared against the wrong
online cpu count. The latter is computed incorrectly using logical-OR
instead of bit-OR. This patch fixes that.
Signed-off-by: Sivaram Nair <sivaramn@nvidia.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Colin Cross <ccross@android.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since cpuidle_state.power_usage is a signed value, use INT_MAX (instead
of -1) to init the local copies so that functions that tries to find
cpuidle states with minimum power usage works correctly even if they use
non-negative values.
Signed-off-by: Sivaram Nair <sivaramn@nvidia.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This contains the bulk of new SoC development for this merge window.
Two new platforms have been added, the sunxi platforms (Allwinner A1x
SoCs) by Maxime Ripard, and a generic Broadcom platform for a new
series of ARMv7 platforms from them, where the hope is that we can
keep the platform code generic enough to have them all share one mach
directory. The new Broadcom platform is contributed by Christian Daudt.
Highbank has grown support for Calxeda's next generation of hardware,
ECX-2000.
clps711x has seen a lot of cleanup from Alexander Shiyan, and he's also
taken on maintainership of the platform.
Beyond this there has been a bunch of work from a number of people on
converting more platforms to IRQ domains, pinctrl conversion, cleanup
and general feature enablement across most of the active platforms.
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Merge tag 'soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC updates from Olof Johansson:
"This contains the bulk of new SoC development for this merge window.
Two new platforms have been added, the sunxi platforms (Allwinner A1x
SoCs) by Maxime Ripard, and a generic Broadcom platform for a new
series of ARMv7 platforms from them, where the hope is that we can
keep the platform code generic enough to have them all share one mach
directory. The new Broadcom platform is contributed by Christian
Daudt.
Highbank has grown support for Calxeda's next generation of hardware,
ECX-2000.
clps711x has seen a lot of cleanup from Alexander Shiyan, and he's
also taken on maintainership of the platform.
Beyond this there has been a bunch of work from a number of people on
converting more platforms to IRQ domains, pinctrl conversion, cleanup
and general feature enablement across most of the active platforms."
Fix up trivial conflicts as per Olof.
* tag 'soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (174 commits)
mfd: vexpress-sysreg: Remove LEDs code
irqchip: irq-sunxi: Add terminating entry for sunxi_irq_dt_ids
clocksource: sunxi_timer: Add terminating entry for sunxi_timer_dt_ids
irq: versatile: delete dangling variable
ARM: sunxi: add missing include for mdelay()
ARM: EXYNOS: Avoid early use of of_machine_is_compatible()
ARM: dts: add node for PL330 MDMA1 controller for exynos4
ARM: EXYNOS: Add support for secondary CPU bring-up on Exynos4412
ARM: EXYNOS: add UART3 to DEBUG_LL ports
ARM: S3C24XX: Add clkdev entry for camif-upll clock
ARM: SAMSUNG: Add s3c24xx/s3c64xx CAMIF GPIO setup helpers
ARM: sunxi: Add missing sun4i.dtsi file
pinctrl: samsung: Do not initialise statics to 0
ARM i.MX6: remove gate_mask from pllv3
ARM i.MX6: Fix ethernet PLL clocks
ARM i.MX6: rename PLLs according to datasheet
ARM i.MX6: Add pwm support
ARM i.MX51: Add pwm support
ARM i.MX53: Add pwm support
ARM: mx5: Replace clk_register_clkdev with clock DT lookup
...
Many cpuidle drivers measure their time spent in an idle state by
reading the wallclock time before and after idling and calculating the
difference. This leads to erroneous results when the wallclock time gets
updated by another processor in the meantime, adding that clock
adjustment to the idle state's time counter.
If the clock adjustment was negative, the result is even worse due to an
erroneous cast from int to unsigned long long of the last_residency
variable. The negative 32 bit integer will zero-extend and result in a
forward time jump of roughly four billion milliseconds or 1.3 hours on
the idle state residency counter.
This patch changes all affected cpuidle drivers to either use the
monotonic clock for their measurements or make use of the generic time
measurement wrapper in cpuidle.c, which was already working correctly.
Some superfluous CLIs/STIs in the ACPI code are removed (interrupts
should always already be disabled before entering the idle function, and
not get reenabled until the generic wrapper has performed its second
measurement). It also removes the erroneous cast, making sure that
negative residency values are applied correctly even though they should
not appear anymore.
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Tested-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
With the tegra3 and the big.LITTLE [1] new architectures, several cpus
with different characteristics (latencies and states) can co-exists on the
system.
The cpuidle framework has the limitation of handling only identical cpus.
This patch removes this limitation by introducing the multiple driver support
for cpuidle.
This option is configurable at compile time and should be enabled for the
architectures mentioned above. So there is no impact for the other platforms
if the option is disabled. The option defaults to 'n'. Note the multiple drivers
support is also compatible with the existing drivers, even if just one driver is
needed, all the cpu will be tied to this driver using an extra small chunk of
processor memory.
The multiple driver support use a per-cpu driver pointer instead of a global
variable and the accessor to this variable are done from a cpu context.
In order to keep the compatibility with the existing drivers, the function
'cpuidle_register_driver' and 'cpuidle_unregister_driver' will register
the specified driver for all the cpus.
The semantic for the output of /sys/devices/system/cpu/cpuidle/current_driver
remains the same except the driver name will be related to the current cpu.
The /sys/devices/system/cpu/cpu[0-9]/cpuidle/driver/name files are added
allowing to read the per cpu driver name.
[1] http://lwn.net/Articles/481055/
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch is a preparation for the multiple cpuidle drivers support.
As the next patch will introduce the multiple drivers with the Kconfig
option and we want to keep the code clean and understandable, this patch
defines a set of functions for encapsulating some common parts and splits
what should be done under a lock from the rest.
[rjw: Modified the subject and changelog slightly.]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The code is racy and the check with cpuidle_curr_driver should be
done under the lock.
I don't find a path in the different drivers where that could happen
because the arch specific drivers are written in such way it is not
possible to register a driver while it is unregistered, except maybe
in a very improbable case when "intel_idle" and "processor_idle" are
competing. One could unregister a driver, while the other one is
registering.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We want to support different cpuidle drivers co-existing together.
In this case we should move the refcount to the cpuidle_driver
structure to handle several drivers at a time.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The "struct device" is only used in sysfs.c.
The other .c files including the private header "cpuidle.h"
do not need to pull the entire headers tree from there as they
don't manipulate the "struct device".
This patch fixes this by moving the header inclusion to sysfs.c
and adding a forward declaration for the struct device.
The number of lines generated by the preprocesor:
Without this patch : 17269 loc
With this patch : 16446 loc
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The structure cpuidle_state_kobj is not used anywhere except
in the sysfs.c file. The definition of this structure is not
needed in the cpuidle header file. This patch moves it to the
sysfs.c file in order to encapsulate the code a bit more.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The function detect_repeating_patterns was not very useful for
workloads with alternating long and short pauses, for example
virtual machines handling network requests for each other (say
a web and database server).
Instead, try to find a recent sleep interval that is somewhere
between the median and the mode sleep time, by discarding outliers
to the up side and recalculating the average and standard deviation
until that is no longer required.
This should do something sane with a sleep interval series like:
200 180 210 10000 30 1000 170 200
The current code would simply discard such a series, while the
new code will guess a typical sleep interval just shy of 200.
The original patch come from Rik van Riel <riel@redhat.com>.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When cpuidle governor choose a C-state to enter for idle CPU, but it notice that
there is tasks request to be executed. So the idle CPU will not really enter
the target C-state and go to run task.
In this situation, it will use the residency of previous really entered target
C-states. Obviously, it is not reasonable.
So, this patch fix it by set the target C-state residency to 0.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The prediction for future is difficult and when the cpuidle governor prediction
fails and govenor possibly choose the shallower C-state than it should. How to
quickly notice and find the failure becomes important for power saving.
The patch extends to general case that prediction logic get a small predicted
residency, so it choose a shallow C-state though the expected residency is large
. Once the prediction will be fail, the CPU will keep staying at shallow C-state
for a long time. Acutally, the CPU has change enter into deep C-state.
So when the expected residency is long enough but governor choose a shallow
C-state, an timer will be added in order to monitor if the prediction failure.
When C-state is waken up prior to the adding timer, the timer will be cancelled
initiatively. When the timer is triggered and menu governor will quickly notice
prediction failure and re-evaluates deeper C-states possibility.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The prediction for future is difficult and when the cpuidle governor prediction
fails and govenor possibly choose the shallower C-state than it should. How to
quickly notice and find the failure becomes important for power saving.
cpuidle menu governor has a method to predict the repeat pattern if there are 8
C-states residency which are continuous and the same or very close, so it will
predict the next C-states residency will keep same residency time.
There is a real case that turbostat utility (tools/power/x86/turbostat)
at kernel 3.3 or early. turbostat utility will read 10 registers one by one at
Sandybridge, so it will generate 10 IPIs to wake up idle CPUs. So cpuidle menu
governor will predict it is repeat mode and there is another IPI wake up idle
CPU soon, so it keeps idle CPU stay at C1 state even though CPU is totally
idle. However, in the turbostat, following 10 registers reading is sleep 5
seconds by default, so the idle CPU will keep at C1 for a long time though it is
idle until break event occurs.
In a idle Sandybridge system, run "./turbostat -v", we will notice that deep
C-state dangles between "70% ~ 99%". After patched the kernel, we will notice
deep C-state stays at >99.98%.
In the patch, a timer is added when menu governor detects a repeat mode and
choose a shallow C-state. The timer is set to a time out value that greater
than predicted time, and we conclude repeat mode prediction failure if timer is
triggered. When repeat mode happens as expected, the timer is not triggered
and CPU waken up from C-states and it will cancel the timer initiatively.
When repeat mode does not happen, the timer will be time out and menu governor
will quickly notice that the repeat mode prediction fails and then re-evaluates
deeper C-states possibility.
Below is another case which will clearly show the patch much benefit:
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <signal.h>
#include <sys/time.h>
#include <time.h>
#include <pthread.h>
volatile int * shutdown;
volatile long * count;
int delay = 20;
int loop = 8;
void usage(void)
{
fprintf(stderr,
"Usage: idle_predict [options]\n"
" --help -h Print this help\n"
" --thread -n Thread number\n"
" --loop -l Loop times in shallow Cstate\n"
" --delay -t Sleep time (uS)in shallow Cstate\n");
}
void *simple_loop() {
int idle_num = 1;
while (!(*shutdown)) {
*count = *count + 1;
if (idle_num % loop)
usleep(delay);
else {
/* sleep 1 second */
usleep(1000000);
idle_num = 0;
}
idle_num++;
}
}
static void sighand(int sig)
{
*shutdown = 1;
}
int main(int argc, char *argv[])
{
sigset_t sigset;
int signum = SIGALRM;
int i, c, er = 0, thread_num = 8;
pthread_t pt[1024];
static char optstr[] = "n:l:t:h:";
while ((c = getopt(argc, argv, optstr)) != EOF)
switch (c) {
case 'n':
thread_num = atoi(optarg);
break;
case 'l':
loop = atoi(optarg);
break;
case 't':
delay = atoi(optarg);
break;
case 'h':
default:
usage();
exit(1);
}
printf("thread=%d,loop=%d,delay=%d\n",thread_num,loop,delay);
count = malloc(sizeof(long));
shutdown = malloc(sizeof(int));
*count = 0;
*shutdown = 0;
sigemptyset(&sigset);
sigaddset(&sigset, signum);
sigprocmask (SIG_BLOCK, &sigset, NULL);
signal(SIGINT, sighand);
signal(SIGTERM, sighand);
for(i = 0; i < thread_num ; i++)
pthread_create(&pt[i], NULL, simple_loop, NULL);
for (i = 0; i < thread_num; i++)
pthread_join(pt[i], NULL);
exit(0);
}
Get powertop V2 from git://github.com/fenrus75/powertop, build powertop.
After build the above test application, then run it.
Test plaform can be Intel Sandybridge or other recent platforms.
#./idle_predict -l 10 &
#./powertop
We will find that deep C-state will dangle between 40%~100% and much time spent
on C1 state. It is because menu governor wrongly predict that repeat mode
is kept, so it will choose the C1 shallow C-state even though it has chance to
sleep 1 second in deep C-state.
While after patched the kernel, we find that deep C-state will keep >99.6%.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Move the kobj initialization and completion in the sysfs.c
and encapsulate the code more.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The function needs the cpuidle_device which is initially passed to the
caller.
The current code gets the struct device from the struct cpuidle_device,
pass it the cpuidle_add_sysfs function. This function calls
per_cpu(cpuidle_devices, cpu) to get the cpuidle_device.
This patch pass the cpuidle_device instead and simplify the code.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add support for core powergating on Calxeda platforms. Initially, this
supports ECX-1000 (highbank), but support will be added for ECX-2000
later.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Len Brown <len.brown@intel.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
The function __cpuidle_register_driver name is confusing because it
suggests, conforming to the coding style of the kernel, it registers
the driver without taking a lock. Actually, it just fill the different
power field states with a decresing value if the power has not been
specified.
Clarify the purpose of the function by changing its name and
move the condition out of this function.
This patch fix nothing and does not change the behavior of the
function. It is just for the sake of clarity.
IHMO, reading in the code:
+ if (!drv->power_specified)
+ set_power_states(drv);
is much more explicit than:
- __cpuidle_register_driver(drv);
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This mindless patch is just about removing some trailing
carriage returns.
[rjw: Changed the subject.]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
For the mechanism introduced by commit cbc9ef0 (PM / Domains: Add
preliminary support for cpuidle, v2) to work with the ladder
governor, that governor should respect the "disabled" state flag
added by that commit. Change the ladder governor accordingly.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
There are two cpuidle governors ladder and menu. While the ladder
governor is always available, if CONFIG_CPU_IDLE is selected, the
menu governor additionally requires CONFIG_NO_HZ.
A particular C state can be disabled by writing to the sysfs file
/sys/devices/system/cpu/cpuN/cpuidle/stateN/disable, but this mechanism
is only implemented in the menu governor. Thus, in a system where
CONFIG_NO_HZ is not selected, the ladder governor becomes default and
always will walk through all sleep states - irrespective of whether the
C state was disabled via sysfs or not. The only way to select a specific
C state was to write the related latency to /dev/cpu_dma_latency and
keep the file open as long as this setting was required - not very
practical and not suitable for setting a single core in an SMP system.
With this patch, the ladder governor only will promote to the next
C state, if it has not been disabled, and it will demote, if the
current C state was disabled.
Note that the patch does not make the setting of the sysfs variable
"disable" coherent, i.e. if one is disabling a light state, then all
deeper states are disabled as well, but the "disable" variable does not
reflect it. Likewise, if one enables a deep state but a lighter state
still is disabled, then this has no effect. A related section has been
added to the documentation.
Signed-off-by: Carsten Emde <C.Emde@osadl.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
When a kernel is built to support multiple hardware types it's possible
that CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED is set but the hardware the
kernel is run on doesn't support cpuidle and therefore doesn't load a
driver for it. In this case, when the system is shut down,
cpuidle_coupled_cpu_notify() gets called with cpuidle_devices set to
NULL. There are quite possibly other circumstances where this
situation can also occur and we should check for it.
Signed-off-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
The cpu hotplug notifier gets called in both atomic and non-atomic
contexts, it is not always safe to lock a mutex. Filter out all events
except the six necessary ones, which are all sleepable, before taking
the mutex.
Signed-off-by: Colin Cross <ccross@android.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Pull ACPI & power management update from Len Brown:
"Re-write of the turbostat tool.
lower overhead was necessary for measuring very large system when
they are very idle.
IVB support in intel_idle
It's what I run on my IVB, others should be able to also:-)
ACPICA core update
We have found some bugs due to divergence between Linux and the
upstream ACPICA base. Most of these patches are to reduce that
divergence to reduce the risk of future bugs.
Some cpuidle updates, mostly for non-Intel
More will be coming, as they depend on this part.
Some thermal management changes needed by non-ACPI systems.
Some _OST (OS Status Indication) updates for hot ACPI hot-plug."
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: (51 commits)
Thermal: Documentation update
Thermal: Add Hysteresis attributes
Thermal: Make Thermal trip points writeable
ACPI/AC: prevent OOPS on some boxes due to missing check power_supply_register() return value check
tools/power: turbostat: fix large c1% issue
tools/power: turbostat v2 - re-write for efficiency
ACPICA: Update to version 20120711
ACPICA: AcpiSrc: Fix some translation issues for Linux conversion
ACPICA: Update header files copyrights to 2012
ACPICA: Add new ACPI table load/unload external interfaces
ACPICA: Split file: tbxface.c -> tbxfload.c
ACPICA: Add PCC address space to space ID decode function
ACPICA: Fix some comment fields
ACPICA: Table manager: deploy new firmware error/warning interfaces
ACPICA: Add new interfaces for BIOS(firmware) errors and warnings
ACPICA: Split exception code utilities to a new file, utexcep.c
ACPI: acpi_pad: tune round_robin_time
ACPICA: Update to version 20120620
ACPICA: Add support for implicit notify on multiple devices
ACPICA: Update comments; no functional change
...
* pm-domains:
PM / Domains: Fix build warning for CONFIG_PM_RUNTIME unset
PM / Domains: Replace plain integer with NULL pointer in domain.c file
PM / Domains: Add missing static storage class specifier in domain.c file
PM / Domains: Allow device callbacks to be added at any time
PM / Domains: Add device domain data reference counter
PM / Domains: Add preliminary support for cpuidle, v2
PM / Domains: Do not stop devices after restoring their states
PM / Domains: Use subsystem runtime suspend/resume callbacks by default
On certain bios, resume hangs if cpus are allowed to enter idle states
during suspend [1].
This was fixed in apci idle driver [2].But intel_idle driver does not
have this fix. Thus instead of replicating the fix in both the idle
drivers, or in more platform specific idle drivers if needed, the
more general cpuidle infrastructure could handle this.
A suspend callback in cpuidle_driver could handle this fix. But
a cpuidle_driver provides only basic functionalities like platform idle
state detection capability and mechanisms to support entry and exit
into CPU idle states. All other cpuidle functions are found in the
cpuidle generic infrastructure for good reason that all cpuidle
drivers, irrepective of their platforms will support these functions.
One option therefore would be to register a suspend callback in cpuidle
which handles this fix. This could be called through a PM_SUSPEND_PREPARE
notifier. But this is too generic a notfier for a driver to handle.
Also, ideally the job of cpuidle is not to handle side effects of suspend.
It should expose the interfaces which "handle cpuidle 'during' suspend"
or any other operation, which the subsystems call during that respective
operation.
The fix demands that during suspend, no cpus should be allowed to enter
deep C-states. The interface cpuidle_uninstall_idle_handler() in cpuidle
ensures that. Not just that it also kicks all the cpus which are already
in idle out of their idle states which was being done during cpu hotplug
through a CPU_DYING_FROZEN callbacks.
Now the question arises about when during suspend should
cpuidle_uninstall_idle_handler() be called. Since we are dealing with
drivers it seems best to call this function during dpm_suspend().
Delaying the call till dpm_suspend_noirq() does no harm, as long as it is
before cpu_hotplug_begin() to avoid race conditions with cpu hotpulg
operations. In dpm_suspend_noirq(), it would be wise to place this call
before suspend_device_irqs() to avoid ugly interactions with the same.
Ananlogously, during resume.
References:
[1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/674075.
[2] http://marc.info/?l=linux-pm&m=133958534231884&w=2
Reported-and-tested-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
On some systems there are CPU cores located in the same power
domains as I/O devices. Then, power can only be removed from the
domain if all I/O devices in it are not in use and the CPU core
is idle. Add preliminary support for that to the generic PM domains
framework.
First, the platform is expected to provide a cpuidle driver with one
extra state designated for use with the generic PM domains code.
This state should be initially disabled and its exit_latency value
should be set to whatever time is needed to bring up the CPU core
itself after restoring power to it, not including the domain's
power on latency. Its .enter() callback should point to a procedure
that will remove power from the domain containing the CPU core at
the end of the CPU power transition.
The remaining characteristics of the extra cpuidle state, referred to
as the "domain" cpuidle state below, (e.g. power usage, target
residency) should be populated in accordance with the properties of
the hardware.
Next, the platform should execute genpd_attach_cpuidle() on the PM
domain containing the CPU core. That will cause the generic PM
domains framework to treat that domain in a special way such that:
* When all devices in the domain have been suspended and it is about
to be turned off, the states of the devices will be saved, but
power will not be removed from the domain. Instead, the "domain"
cpuidle state will be enabled so that power can be removed from
the domain when the CPU core is idle and the state has been chosen
as the target by the cpuidle governor.
* When the first I/O device in the domain is resumed and
__pm_genpd_poweron(() is called for the first time after
power has been removed from the domain, the "domain" cpuidle
state will be disabled to avoid subsequent surprise power removals
via cpuidle.
The effective exit_latency value of the "domain" cpuidle state
depends on the time needed to bring up the CPU core itself after
restoring power to it as well as on the power on latency of the
domain containing the CPU core. Thus the "domain" cpuidle state's
exit_latency has to be recomputed every time the domain's power on
latency is updated, which may happen every time power is restored
to the domain, if the measured power on latency is greater than
the latency stored in the corresponding generic_pm_domain structure.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Andrew J.Schorr raises a question. When he changes the disable setting on
a single CPU, it affects all the other CPUs. Basically, currently, the
disable field is per-driver instead of per-cpu. All the C states of the
same driver are shared by all CPU in the same machine.
The patch changes the `disable' field to per-cpu, so we could set this
separately for each cpu.
Signed-off-by: ShuoX Liu <shuox.liu@intel.com>
Reported-by: Andrew J.Schorr <aschorr@telemetry-investments.com>
Reviewed-by: Yanmin Zhang <yanmin_zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Adds cpuidle_coupled_parallel_barrier, which can be used by coupled
cpuidle state enter functions to handle resynchronization after
determining if any cpu needs to abort. The normal use case will
be:
static bool abort_flag;
static atomic_t abort_barrier;
int arch_cpuidle_enter(struct cpuidle_device *dev, ...)
{
if (arch_turn_off_irq_controller()) {
/* returns an error if an irq is pending and would be lost
if idle continued and turned off power */
abort_flag = true;
}
cpuidle_coupled_parallel_barrier(dev, &abort_barrier);
if (abort_flag) {
/* One of the cpus didn't turn off it's irq controller */
arch_turn_on_irq_controller();
return -EINTR;
}
/* continue with idle */
...
}
This will cause all cpus to abort idle together if one of them needs
to abort.
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Len Brown <len.brown@intel.com>
On some ARM SMP SoCs (OMAP4460, Tegra 2, and probably more), the
cpus cannot be independently powered down, either due to
sequencing restrictions (on Tegra 2, cpu 0 must be the last to
power down), or due to HW bugs (on OMAP4460, a cpu powering up
will corrupt the gic state unless the other cpu runs a work
around). Each cpu has a power state that it can enter without
coordinating with the other cpu (usually Wait For Interrupt, or
WFI), and one or more "coupled" power states that affect blocks
shared between the cpus (L2 cache, interrupt controller, and
sometimes the whole SoC). Entering a coupled power state must
be tightly controlled on both cpus.
The easiest solution to implementing coupled cpu power states is
to hotplug all but one cpu whenever possible, usually using a
cpufreq governor that looks at cpu load to determine when to
enable the secondary cpus. This causes problems, as hotplug is an
expensive operation, so the number of hotplug transitions must be
minimized, leading to very slow response to loads, often on the
order of seconds.
This file implements an alternative solution, where each cpu will
wait in the WFI state until all cpus are ready to enter a coupled
state, at which point the coupled state function will be called
on all cpus at approximately the same time.
Once all cpus are ready to enter idle, they are woken by an smp
cross call. At this point, there is a chance that one of the
cpus will find work to do, and choose not to enter idle. A
final pass is needed to guarantee that all cpus will call the
power state enter function at the same time. During this pass,
each cpu will increment the ready counter, and continue once the
ready counter matches the number of online coupled cpus. If any
cpu exits idle, the other cpus will decrement their counter and
retry.
To use coupled cpuidle states, a cpuidle driver must:
Set struct cpuidle_device.coupled_cpus to the mask of all
coupled cpus, usually the same as cpu_possible_mask if all cpus
are part of the same cluster. The coupled_cpus mask must be
set in the struct cpuidle_device for each cpu.
Set struct cpuidle_device.safe_state to a state that is not a
coupled state. This is usually WFI.
Set CPUIDLE_FLAG_COUPLED in struct cpuidle_state.flags for each
state that affects multiple cpus.
Provide a struct cpuidle_state.enter function for each state
that affects multiple cpus. This function is guaranteed to be
called on all cpus at approximately the same time. The driver
should ensure that the cpus all abort together if any cpu tries
to abort once the function is called.
update1:
cpuidle: coupled: fix count of online cpus
online_count was never incremented on boot, and was also counting
cpus that were not part of the coupled set. Fix both issues by
introducting a new function that counts online coupled cpus, and
call it from register as well as the hotplug notifier.
update2:
cpuidle: coupled: fix decrementing ready count
cpuidle_coupled_set_not_ready sometimes refuses to decrement the
ready count in order to prevent a race condition. This makes it
unsuitable for use when finished with idle. Add a new function
cpuidle_coupled_set_done that decrements both the ready count and
waiting count, and call it after idle is complete.
Cc: Amit Kucheria <amit.kucheria@linaro.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Trinabh Gupta <g.trinabh@gmail.com>
Cc: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Colin Cross <ccross@android.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
Fix the error handling in __cpuidle_register_device to include
the missing list_del. Move it to a label, which will simplify
the error handling when coupled states are added.
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Colin Cross <ccross@android.com>
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
Split the code to enter a state and update the stats into a helper
function, cpuidle_enter_state, and export it. This function will
be called by the coupled state code to handle entering the safe
state and the final coupled state.
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Colin Cross <ccross@android.com>
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
The existing check for dev == NULL in __cpuidle_register_device() is
rendered useless because dev is dereferenced before the check itself.
Moreover, correctly speaking, it is the job of the callers of this
function, i.e., cpuidle_register_device() & cpuidle_enable_device() (which
also happen to be exported functions) to ensure that
__cpuidle_register_device() is called with a non-NULL dev.
So add the necessary dev == NULL checks in the two callers and remove the
(useless) check from __cpuidle_register_device().
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
commit 9a6558371b
Author: Arjan van de Ven <arjan@linux.intel.com>
Date: Sun Nov 9 12:45:10 2008 -0800
regression: disable timer peek-ahead for 2.6.28
It's showing up as regressions; disabling it very likely just papers
over an underlying issue, but time is running out for 2.6.28, lets get
back to this for 2.6.29
Many years has passed since 2008, so it seems ok to remove whole `#if 0' block.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Trinabh Gupta <g.trinabh@gmail.com>
Cc: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
kick_all_cpus_sync() is the core implementation of cpu_idle_wait()
which is copied all over the arch code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120507175652.119842173@linutronix.de
Fix a NULL pointer dereference panic in cpuidle_play_dead() during
CPU off-lining when no cpuidle driver is registered. A cpuidle
driver may be registered at boot-time based on CPU type. This patch
allows an off-lined CPU to enter HLT-based idle in this condition.
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: Boris Ostrovsky <boris.ostrovsky@amd.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Tested-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Pull ACPI & Power Management changes from Len Brown:
- ACPI 5.0 after-ripples, ACPICA/Linux divergence cleanup
- cpuidle evolving, more ARM use
- thermal sub-system evolving, ditto
- assorted other PM bits
Fix up conflicts in various cpuidle implementations due to ARM cpuidle
cleanups (ARM at91 self-refresh and cpu idle code rewritten into
"standby" in asm conflicting with the consolidation of cpuidle time
keeping), trivial SH include file context conflict and RCU tracing fixes
in generic code.
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: (77 commits)
ACPI throttling: fix endian bug in acpi_read_throttling_status()
Disable MCP limit exceeded messages from Intel IPS driver
ACPI video: Don't start video device until its associated input device has been allocated
ACPI video: Harden video bus adding.
ACPI: Add support for exposing BGRT data
ACPI: export acpi_kobj
ACPI: Fix logic for removing mappings in 'acpi_unmap'
CPER failed to handle generic error records with multiple sections
ACPI: Clean redundant codes in scan.c
ACPI: Fix unprotected smp_processor_id() in acpi_processor_cst_has_changed()
ACPI: consistently use should_use_kmap()
PNPACPI: Fix device ref leaking in acpi_pnp_match
ACPI: Fix use-after-free in acpi_map_lsapic
ACPI: processor_driver: add missing kfree
ACPI, APEI: Fix incorrect APEI register bit width check and usage
Update documentation for parameter *notrigger* in einj.txt
ACPI, APEI, EINJ, new parameter to control trigger action
ACPI, APEI, EINJ, limit the range of einj_param
ACPI, APEI, Fix ERST header length check
cpuidle: power_usage should be declared signed integer
...
power_usage is always assigned a negative value and should be declared
a signed integer
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@amd.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Currently when a CPU is off-lined it enters either MWAIT-based idle or,
if MWAIT is not desired or supported, HLT-based idle (which places the
processor in C1 state). This patch allows processors without MWAIT
support to stay in states deeper than C1.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@amd.com>
Signed-off-by: Len Brown <len.brown@intel.com>
If the state_count is not initialized for the device use
the driver's state count as the default. That will prevent
to add it manually in the cpuidle driver initialization
routine and will save us from duplicate line of code.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Len Brown <len.brown@intel.com>
Some C states of new CPU might be not good. One reason is BIOS might
configure them incorrectly. To help developers root cause it quickly, the
patch adds a new sysfs entry, so developers could disable specific C state
manually.
In addition, C state might have much impact on performance tuning, as it
takes much time to enter/exit C states, which might delay interrupt
processing. With the new debug option, developers could check if a deep C
state could impact performance and how much impact it could cause.
Also add this option in Documentation/cpuidle/sysfs.txt.
[akpm@linux-foundation.org: check kstrtol return value]
Signed-off-by: ShuoX Liu <shuox.liu@intel.com>
Reviewed-by: Yanmin Zhang <yanmin_zhang@intel.com>
Reviewed-and-Tested-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
Make necessary changes to implement time keeping and irq enabling
in the core cpuidle code. This will allow the removal of these
functionalities from various platform cpuidle implementations whose
timekeeping and irq enabling follows the form in this common code.
Signed-off-by: Robert Lee <rob.lee@linaro.org>
Tested-by: Jean Pihet <j-pihet@ti.com>
Tested-by: Amit Daniel <amit.kachhap@linaro.org>
Tested-by: Robert Lee <rob.lee@linaro.org>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Len Brown <len.brown@intel.com>
We moved all our pSeries idle loops to the cpu idle framework
so we really want it to come up by default.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
As the tracepoints in the cpuidle code are called when rcu_idle_exit() is in
effect, the _rcuidle() version must be used, otherwise the rcu_read_lock()s
that protect the tracepoint will not be honored.
Cc: Len Brown <len.brown@intel.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This moves the 'cpu sysdev_class' over to a regular 'cpu' subsystem
and converts the devices to regular devices. The sysdev drivers are
implemented as subsystem interfaces now.
After all sysdev classes are ported to regular driver core entities, the
sysdev implementation will be entirely removed from the kernel.
Userspace relies on events and generic sysfs subsystem infrastructure
from sysdev devices, which are made available with this conversion.
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Borislav Petkov <bp@amd64.org>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Cc: Len Brown <lenb@kernel.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
cpuidle: Single/Global registration of idle states
cpuidle: Split cpuidle_state structure and move per-cpu statistics fields
cpuidle: Remove CPUIDLE_FLAG_IGNORE and dev->prepare()
cpuidle: Move dev->last_residency update to driver enter routine; remove dev->last_state
ACPI: Fix CONFIG_ACPI_DOCK=n compiler warning
ACPI: Export FADT pm_profile integer value to userspace
thermal: Prevent polling from happening during system suspend
ACPI: Drop ACPI_NO_HARDWARE_INIT
ACPI atomicio: Convert width in bits to bytes in __acpi_ioremap_fast()
PNPACPI: Simplify disabled resource registration
ACPI: Fix possible recursive locking in hwregs.c
ACPI: use kstrdup()
mrst pmu: update comment
tools/power turbostat: less verbose debugging
This patch makes the cpuidle_states structure global (single copy)
instead of per-cpu. The statistics needed on per-cpu basis
by the governor are kept per-cpu. This simplifies the cpuidle
subsystem as state registration is done by single cpu only.
Having single copy of cpuidle_states saves memory. Rare case
of asymmetric C-states can be handled within the cpuidle driver
and architectures such as POWER do not have asymmetric C-states.
Having single/global registration of all the idle states,
dynamic C-state transitions on x86 are handled by
the boot cpu. Here, the boot cpu would disable all the devices,
re-populate the states and later enable all the devices,
irrespective of the cpu that would receive the notification first.
Reference:
https://lkml.org/lkml/2011/4/25/83
Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Trinabh Gupta <g.trinabh@gmail.com>
Tested-by: Jean Pihet <j-pihet@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This is the first step towards global registration of cpuidle
states. The statistics used primarily by the governor are per-cpu
and have to be split from rest of the fields inside cpuidle_state,
which would be made global i.e. single copy. The driver_data field
is also per-cpu and moved.
Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Trinabh Gupta <g.trinabh@gmail.com>
Tested-by: Jean Pihet <j-pihet@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Len Brown <len.brown@intel.com>
The cpuidle_device->prepare() mechanism causes updates to the
cpuidle_state[].flags, setting and clearing CPUIDLE_FLAG_IGNORE
to tell the governor not to chose a state on a per-cpu basis at
run-time. State demotion is now handled by the driver and it returns
the actual state entered. Hence, this mechanism is not required.
Also this removes per-cpu flags from cpuidle_state enabling
it to be made global.
Reference:
https://lkml.org/lkml/2011/3/25/52
Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm>
Signed-off-by: Trinabh Gupta <g.trinabh@gmail.com>
Tested-by: Jean Pihet <j-pihet@ti.com>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Cpuidle governor only suggests the state to enter using the
governor->select() interface, but allows the low level driver to
override the recommended state. The actual entered state
may be different because of software or hardware demotion. Software
demotion is done by the back-end cpuidle driver and can be accounted
correctly. Current cpuidle code uses last_state field to capture the
actual state entered and based on that updates the statistics for the
state entered.
Ideally the driver enter routine should update the counters,
and it should return the state actually entered rather than the time
spent there. The generic cpuidle code should simply handle where
the counters live in the sysfs namespace, not updating the counters.
Reference:
https://lkml.org/lkml/2011/3/25/52
Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Trinabh Gupta <g.trinabh@gmail.com>
Tested-by: Jean Pihet <j-pihet@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This file has module_init/exit and MODULE_LICENSE, and so it
needs the full module.h header.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The PM QoS implementation files are better named
kernel/power/qos.c and include/linux/pm_qos.h.
The PM QoS support is compiled under the CONFIG_PM option.
Signed-off-by: Jean Pihet <j-pihet@ti.com>
Acked-by: markgross <markgross@thegnar.org>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
cpuidle users should call cpuidle_call_idle() directly
rather than via (pm_idle)() function pointer.
Architecture may choose to continue using (pm_idle)(),
but cpuidle need not depend on it:
my_arch_cpu_idle()
...
if(cpuidle_call_idle())
pm_idle();
cc: Kevin Hilman <khilman@deeprootsystems.com>
cc: Paul Mundt <lethal@linux-sh.org>
cc: x86@kernel.org
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
When a Xen Dom0 kernel boots on a hypervisor, it gets access
to the raw-hardware ACPI tables. While it parses the idle tables
for the hypervisor's beneift, it uses HLT for its own idle.
Rather than have xen scribble on pm_idle and access default_idle,
have it simply disable_cpuidle() so acpi_idle will not load and
architecture default HLT will be used.
cc: xen-devel@lists.xensource.com
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
useful for disabling cpuidle to fall back
to architecture-default idle loop
cpuidle drivers and governors will fail to register.
on x86 they'll say so:
intel_idle: intel_idle yielding to (null)
ACPI: acpi_idle yielding to (null)
Signed-off-by: Len Brown <len.brown@intel.com>
* 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6:
x86 idle: deprecate mwait_idle() and "idle=mwait" cmdline param
x86 idle: deprecate "no-hlt" cmdline param
x86 idle APM: deprecate CONFIG_APM_CPU_IDLE
x86 idle floppy: deprecate disable_hlt()
x86 idle: EXPORT_SYMBOL(default_idle, pm_idle) only when APM demands it
x86 idle: clarify AMD erratum 400 workaround
idle governor: Avoid lock acquisition to read pm_qos before entering idle
cpuidle: menu: fixed wrapping timers at 4.294 seconds
Cpuidle menu governor is using u32 as a temporary datatype for storing
nanosecond values which wrap around at 4.294 seconds. This causes errors
in predicted sleep times resulting in higher than should be C state
selection and increased power consumption. This also breaks cpuidle
state residency statistics.
cc: stable@kernel.org # .32.x through .39.x
Signed-off-by: Tero Kristo <tero.kristo@nokia.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Fix a bunch of
warning: ‘inline’ is not at beginning of declaration
messages when building a 'make allyesconfig' kernel with -Wextra.
These warnings are trivial to kill, yet rather annoying when building with
-Wextra.
The more we can cut down on pointless crap like this the better (IMHO).
A previous patch to do this for a 'allnoconfig' build has already been
merged. This just takes the cleanup a little further.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Currently intel_idle and acpi_idle driver show double cpu_idle "exit idle"
events -> this patch fixes it and makes cpu_idle events throwing less complex.
It also introduces cpu_idle events for all architectures which use
the cpuidle subsystem, namely:
- arch/arm/mach-at91/cpuidle.c
- arch/arm/mach-davinci/cpuidle.c
- arch/arm/mach-kirkwood/cpuidle.c
- arch/arm/mach-omap2/cpuidle34xx.c
- arch/drivers/acpi/processor_idle.c (for all cases, not only mwait)
- arch/x86/kernel/process.c (did throw events before, but was a mess)
- drivers/idle/intel_idle.c (did throw events before)
Convention should be:
Fire cpu_idle events inside the current pm_idle function (not somewhere
down the the callee tree) to keep things easy.
Current possible pm_idle functions in X86:
c1e_idle, poll_idle, cpuidle_idle_call, mwait_idle, default_idle
-> this is really easy is now.
This affects userspace:
The type field of the cpu_idle power event can now direclty get
mapped to:
/sys/devices/system/cpu/cpuX/cpuidle/stateX/{name,desc,usage,time,...}
instead of throwing very CPU/mwait specific values.
This change is not visible for the intel_idle driver.
For the acpi_idle driver it should only be visible if the vendor
misses out C-states in his BIOS.
Another (perf timechart) patch reads out cpuidle info of cpu_idle
events from:
/sys/.../cpuidle/stateX/*, then the cpuidle events are mapped
to the correct C-/cpuidle state again, even if e.g. vendors miss
out C-states in their BIOS and for example only export C1 and C3.
-> everything is fine.
Signed-off-by: Thomas Renninger <trenn@suse.de>
CC: Robert Schoene <robert.schoene@tu-dresden.de>
CC: Jean Pihet <j-pihet@ti.com>
CC: Arjan van de Ven <arjan@linux.intel.com>
CC: Ingo Molnar <mingo@elte.hu>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: linux-pm@lists.linux-foundation.org
CC: linux-acpi@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: linux-perf-users@vger.kernel.org
CC: linux-omap@vger.kernel.org
Signed-off-by: Len Brown <len.brown@intel.com>
Daniel Lezcano