- 17 12月, 2014 1 次提交
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由 Len Brown 提交于
CPUIDLE_FLAG_TIME_INVALID is no longer checked by menu or ladder cpuidle governors, so don't bother setting or defining it. It was originally invented to account for the fact that acpi_safe_halt() enables interrupts to invoke HLT. That would allow interrupt service routines to be included in the last_idle duration measurements made in cpuidle_enter_state(), potentially returning a duration much larger than reality. But menu and ladder can gracefully handle erroneously large duration intervals without checking for CPUIDLE_FLAG_TIME_INVALID. Further, if they don't check CPUIDLE_FLAG_TIME_INVALID, they can also benefit from the instances when the duration interval is not erroneously large. Signed-off-by: NLen Brown <len.brown@intel.com> Acked-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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- 13 11月, 2014 1 次提交
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由 Daniel Lezcano 提交于
The only place where the time is invalid is when the ACPI_CSTATE_FFH entry method is not set. Otherwise for all the drivers, the time can be correctly measured. Instead of duplicating the CPUIDLE_FLAG_TIME_VALID flag in all the drivers for all the states, just invert the logic by replacing it by the flag CPUIDLE_FLAG_TIME_INVALID, hence we can set this flag only for the acpi idle driver, remove the former flag from all the drivers and invert the logic with this flag in the different governor. Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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- 28 5月, 2014 1 次提交
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由 Paul Burton 提交于
Declaring this allows drivers which need to initialise each struct cpuidle_device at initialisation time to make use of the structures already defined in cpuidle.c, rather than having to wastefully define their own. Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
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- 07 5月, 2014 1 次提交
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由 Rafael J. Wysocki 提交于
If freeze_enter() is called, we want to bypass the current cpuidle governor and always use the deepest available (that is, not disabled) C-state, because we want to save as much energy as reasonably possible then and runtime latency constraints don't matter at that point, since the system is in a sleep state anyway. Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: NAubrey Li <aubrey.li@linux.intel.com>
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- 01 5月, 2014 1 次提交
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由 Rafael J. Wysocki 提交于
Since both cpuidle_enabled() and cpuidle_select() are only called by cpuidle_idle_call(), it is not really useful to keep them separate and combining them will help to avoid complicating cpuidle_idle_call() even further if governors are changed to return error codes sometimes. This code modification shouldn't lead to any functional changes. Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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- 11 3月, 2014 3 次提交
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由 Daniel Lezcano 提交于
Now that we have the main cpuidle function in idle.c, move some code from the idle mainloop to this function for the sake of clarity. That removes if then else indentation difficult to follow when looking at the code. This patch does not change the current behavior. Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Acked-by: NNicolas Pitre <nico@linaro.org> Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Cc: tglx@linutronix.de Cc: rjw@rjwysocki.net Cc: preeti@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/1393832934-11625-3-git-send-email-daniel.lezcano@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
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由 Daniel Lezcano 提交于
The cpuidle_idle_call does nothing more than calling the three individuals function and is no longer used by any arch specific code but only in the cpuidle framework code. We can move this function into the idle task code to ensure better proximity to the scheduler code. Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Acked-by: NNicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Cc: rjw@rjwysocki.net Cc: preeti@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/1393832934-11625-2-git-send-email-daniel.lezcano@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
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由 Daniel Lezcano 提交于
In order to allow better integration between the cpuidle framework and the scheduler, reducing the distance between these two sub-components will facilitate this integration by moving part of the cpuidle code in the idle task file and, because idle.c is in the sched directory, we have access to the scheduler's private structures. This patch splits the cpuidle_idle_call main entry function into 3 calls to a newly added API: 1. select the idle state 2. enter the idle state 3. reflect the idle state The cpuidle_idle_call calls these three functions to implement the main idle entry function. Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Acked-by: NNicolas Pitre <nico@linaro.org> Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Cc: rjw@rjwysocki.net Cc: preeti@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/1393832934-11625-1-git-send-email-daniel.lezcano@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
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- 30 10月, 2013 2 次提交
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由 Viresh Kumar 提交于
cpuidle_unregister_governor() and cpuidle_replace_governor() aren't used anymore and can be removed. They were used by cpufreq governors earlier, but since the governors can't be compiled as modules any more, these two functions aren't necessary. Suggested-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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由 Viresh Kumar 提交于
Use tabs for cpumask indentation in struct cpuidle_driver. [rjw: Changelog] Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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- 15 7月, 2013 2 次提交
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由 Daniel Lezcano 提交于
Add missing forward declarations of struct cpuidle_state_kobj and struct cpuidle_driver_kobj in cpuidle.h. [rjw: Changelog] Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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由 Daniel Lezcano 提交于
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: NDaniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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- 11 6月, 2013 1 次提交
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由 Daniel Lezcano 提交于
Commit bf4d1b5d (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: NDaniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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- 23 4月, 2013 2 次提交
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由 Daniel Lezcano 提交于
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: NDaniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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由 Daniel Lezcano 提交于
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: NDaniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Kevin Hilman <khilman@linaro.org> # for mach-omap2/* Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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- 18 4月, 2013 1 次提交
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由 Len Brown 提交于
Allow intel_idle and cpuidle to utilize C8, C9, C10 when they are present on... "Fourth Generation Intel(R) Core(TM) Processors", which are based on Intel(R) microarchitecture code name Haswell. Signed-off-by: NLen Brown <len.brown@intel.com>
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- 01 4月, 2013 2 次提交
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由 Daniel Lezcano 提交于
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: NDaniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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由 Daniel Lezcano 提交于
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: NDaniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: NThomas Gleixner <tglx@linutronix.de> Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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- 12 2月, 2013 1 次提交
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由 Len Brown 提交于
This field is no longer used. Signed-off-by: NLen Brown <len.brown@intel.com> Acked-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
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- 15 1月, 2013 1 次提交
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由 Daniel Lezcano 提交于
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/2012/10/16/518Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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- 15 11月, 2012 3 次提交
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由 Daniel Lezcano 提交于
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: NDaniel Lezcano <daniel.lezcano@linaro.org> Acked-by: NPeter De Schrijver <pdeschrijver@nvidia.com> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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由 Daniel Lezcano 提交于
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: NDaniel Lezcano <daniel.lezcano@linaro.org> Acked-by: NPeter De Schrijver <pdeschrijver@nvidia.com> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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由 Daniel Lezcano 提交于
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: NDaniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
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- 23 8月, 2012 1 次提交
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由 Arnd Bergmann 提交于
The new omap4 cpuidle implementation currently requires ARCH_NEEDS_CPU_IDLE_COUPLED, which only works on SMP. This patch makes it possible to build a non-SMP kernel for that platform. This is not normally desired for end-users but can be useful for testing. Without this patch, building rand-0y2jSKT results in: drivers/cpuidle/coupled.c: In function 'cpuidle_coupled_poke': drivers/cpuidle/coupled.c:317:3: error: implicit declaration of function '__smp_call_function_single' [-Werror=implicit-function-declaration] It's not clear if this patch is the best solution for the problem at hand. I have made sure that we can now build the kernel in all configurations, but that does not mean it will actually work on an OMAP44xx. Signed-off-by: NArnd Bergmann <arnd@arndb.de> Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com> Cc: Kevin Hilman <khilman@ti.com> Cc: Tony Lindgren <tony@atomide.com>
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- 11 7月, 2012 1 次提交
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由 Preeti U Murthy 提交于
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=2Reported-and-tested-by: NDave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: NPreeti U Murthy <preeti@linux.vnet.ibm.com> Reviewed-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
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- 06 7月, 2012 1 次提交
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由 Daniel Lezcano 提交于
When the system is booted with some cpus offline, the idle driver is not initialized. When a cpu is set online, the acpi code call the intel idle init function. Unfortunately this code introduce a dependency between intel_idle and acpi. This patch is intended to remove this dependency by using the notifier of intel_idle. This patch has the benefit of encapsulating the intel_idle driver and remove some exported functions. Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Acked-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
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- 04 7月, 2012 3 次提交
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由 Rafael J. Wysocki 提交于
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: NRafael J. Wysocki <rjw@sisk.pl> Reviewed-by: NKevin Hilman <khilman@ti.com>
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由 Rafael J. Wysocki 提交于
Add a reference counter for the cpuidle driver, so that it can't be unregistered when it is in use. Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
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由 ShuoX Liu 提交于
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: NShuoX Liu <shuox.liu@intel.com> Reported-by: NAndrew J.Schorr <aschorr@telemetry-investments.com> Reviewed-by: NYanmin Zhang <yanmin_zhang@intel.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
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- 02 6月, 2012 2 次提交
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由 Colin Cross 提交于
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: NSantosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com> Reviewed-by: NKevin Hilman <khilman@ti.com> Tested-by: NKevin Hilman <khilman@ti.com> Signed-off-by: NColin Cross <ccross@android.com> Signed-off-by: NLen Brown <len.brown@intel.com>
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由 Colin Cross 提交于
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: NSantosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com> Reviewed-by: NKevin Hilman <khilman@ti.com> Tested-by: NKevin Hilman <khilman@ti.com> Signed-off-by: NColin Cross <ccross@android.com> Acked-by: NRafael J. Wysocki <rjw@sisk.pl> Signed-off-by: NLen Brown <len.brown@intel.com>
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- 30 3月, 2012 5 次提交
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由 Boris Ostrovsky 提交于
power_usage is always assigned a negative value and should be declared a signed integer Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@amd.com> Signed-off-by: NLen Brown <len.brown@intel.com>
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由 Boris Ostrovsky 提交于
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: NBoris Ostrovsky <boris.ostrovsky@amd.com> Signed-off-by: NLen Brown <len.brown@intel.com>
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由 Daniel Lezcano 提交于
As far as I can see, this field is never used in the code. Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: NLen Brown <len.brown@intel.com>
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由 Daniel Lezcano 提交于
All the modules name are ro-data, it is never copied to the array. eg. static struct cpuidle_driver intel_idle_driver = { .name = "intel_idle", .owner = THIS_MODULE, }; It safe to assign the pointer of this ro-data to a const char *. By this way we save 12 bytes. Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Acked-by: NDeepthi Dharwar <deepthi@linux.vnet.ibm.com> Tested-by: NDeepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: NLen Brown <len.brown@intel.com>
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由 ShuoX Liu 提交于
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: NShuoX Liu <shuox.liu@intel.com> Reviewed-by: NYanmin Zhang <yanmin_zhang@intel.com> Reviewed-and-Tested-by: NDeepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLen Brown <len.brown@intel.com>
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- 21 3月, 2012 1 次提交
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由 Robert Lee 提交于
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: NRobert Lee <rob.lee@linaro.org> Tested-by: NJean Pihet <j-pihet@ti.com> Tested-by: NAmit Daniel <amit.kachhap@linaro.org> Tested-by: NRobert Lee <rob.lee@linaro.org> Reviewed-by: NKevin Hilman <khilman@ti.com> Reviewed-by: NDaniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: NDeepthi Dharwar <deepthi@linux.vnet.ibm.com> Acked-by: NJean Pihet <j-pihet@ti.com> Signed-off-by: NLen Brown <len.brown@intel.com>
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- 18 1月, 2012 1 次提交
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由 Thomas Renninger 提交于
Function split up, should have no functional change. Provides entry point for physically hotplugged CPUs to initialize and activate cpuidle. Signed-off-by: NThomas Renninger <trenn@suse.de> CC: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> CC: Shaohua Li <shaohua.li@intel.com> CC: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: NLen Brown <len.brown@intel.com>
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- 08 12月, 2011 1 次提交
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由 Deepthi Dharwar 提交于
This patch enables cpuidle for pSeries and pSeries_idle is directly called from the idle loop. As a result of pSeries_idle, cpuidle driver registered with cpuidle subsystem comes into action. On failure of loading of the driver or cpuidle framework default idle is executed as part of the function. This patch also removes the routines pseries_shared_idle_sleep and pseries_dedicated_idle_sleep as they are now implemented as part of pseries_idle cpuidle driver. Signed-off-by: NDeepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: NTrinabh Gupta <g.trinabh@gmail.com> Signed-off-by: NArun R Bharadwaj <arun.r.bharadwaj@gmail.com> Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
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- 07 11月, 2011 1 次提交
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由 Deepthi Dharwar 提交于
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/2011/4/25/83Signed-off-by: NDeepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: NTrinabh Gupta <g.trinabh@gmail.com> Tested-by: NJean Pihet <j-pihet@ti.com> Reviewed-by: NKevin Hilman <khilman@ti.com> Acked-by: NArjan van de Ven <arjan@linux.intel.com> Acked-by: NKevin Hilman <khilman@ti.com> Signed-off-by: NLen Brown <len.brown@intel.com>
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