summaryrefslogtreecommitdiff
path: root/include/linux/pm_qos_params.h
AgeCommit message (Collapse)Author
2012-05-31PM QoS: Set minimum online cpus default to zeroAlex Frid
Change default PM QoS request value for minimum online cpus parameter from 1 to 0. This is consistent with all other PM_QOS_MAX type parameters, and allow to differentiate request for 1 CPU and "no request". Change-Id: I548449d0b7a443b77f7f065e1e1f10dffc5587ed Signed-off-by: Alex Frid <afrid@nvidia.com> Reviewed-on: http://git-master/r/102119 Reviewed-by: Automatic_Commit_Validation_User Reviewed-by: Donghan Ryu <dryu@nvidia.com> Reviewed-by: Satya Popuri <spopuri@nvidia.com> Reviewed-by: Diwakar Tundlam <dtundlam@nvidia.com> GVS: Gerrit_Virtual_Submit Reviewed-by: Yu-Huan Hsu <yhsu@nvidia.com>
2012-02-27PM Qos: Add min online cpus as PM QoS parameterGaurav Sarode
Bug 940061 Change-Id: Ibae842fdc3af3c92ec7e6125c602417110d8b55e Signed-off-by: Gaurav Sarode <gsarode@nvidia.com> Reviewed-on: http://git-master/r/84521 Reviewed-by: Sachin Nikam <snikam@nvidia.com> Tested-by: Aleksandr Frid <afrid@nvidia.com> Reviewed-by: Diwakar Tundlam <dtundlam@nvidia.com>
2012-01-19PM QoS: Add CPU frequency min/max as PM QoS paramsAntti P Miettinen
Add minimum and maximum CPU frequency as PM QoS parameters. Bug 888312 Change-Id: I18abddded35a044a6ad8365035e31d1a2213a329 Reviewed-on: http://git-master/r/72206 Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com> Signed-off-by: Varun Wadekar <vwadekar@nvidia.com> Reviewed-on: http://git-master/r/75883 Reviewed-by: Automatic_Commit_Validation_User
2011-12-22PM QoS: Add max online cpus as PM QoS parameterAlex Frid
Bug 894200 Change-Id: Ieb009a13c6ef9bca2388e234eb973d65a4e3a58b Signed-off-by: Alex Frid <afrid@nvidia.com> Reviewed-on: http://git-master/r/71034 Reviewed-by: Rohan Somvanshi <rsomvanshi@nvidia.com> Tested-by: Rohan Somvanshi <rsomvanshi@nvidia.com>
2011-12-22PM QoS: Simplify PM QoS expansion/mergeAlex Frid
- Replace class ID #define with enumeration - Loop through PM QoS objects during initialization (rather than initializing them one-by-one) Change-Id: I185b700b52c752c62e7550fe739adc498fc989ef Signed-off-by: Alex Frid <afrid@nvidia.com> Reviewed-on: http://git-master/r/70603 Reviewed-by: Automatic_Commit_Validation_User Reviewed-by: Antti Miettinen <amiettinen@nvidia.com> Reviewed-by: Diwakar Tundlam <dtundlam@nvidia.com> Reviewed-by: Scott Williams <scwilliams@nvidia.com> Reviewed-by: Yu-Huan Hsu <yhsu@nvidia.com>
2011-05-29idle governor: Avoid lock acquisition to read pm_qos before entering idleTim Chen
Thanks to the reviews and comments by Rafael, James, Mark and Andi. Here's version 2 of the patch incorporating your comments and also some update to my previous patch comments. I noticed that before entering idle state, the menu idle governor will look up the current pm_qos target value according to the list of qos requests received. This look up currently needs the acquisition of a lock to access the list of qos requests to find the qos target value, slowing down the entrance into idle state due to contention by multiple cpus to access this list. The contention is severe when there are a lot of cpus waking and going into idle. For example, for a simple workload that has 32 pair of processes ping ponging messages to each other, where 64 cpu cores are active in test system, I see the following profile with 37.82% of cpu cycles spent in contention of pm_qos_lock: - 37.82% swapper [kernel.kallsyms] [k] _raw_spin_lock_irqsave - _raw_spin_lock_irqsave - 95.65% pm_qos_request menu_select cpuidle_idle_call - cpu_idle 99.98% start_secondary A better approach will be to cache the updated pm_qos target value so reading it does not require lock acquisition as in the patch below. With this patch the contention for pm_qos_lock is removed and I saw a 2.2X increase in throughput for my message passing workload. cc: stable@kernel.org Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com> Acked-by: Andi Kleen <ak@linux.intel.com> Acked-by: James Bottomley <James.Bottomley@suse.de> Acked-by: mark gross <markgross@thegnar.org> Signed-off-by: Len Brown <len.brown@intel.com>
2010-07-19pm_qos: Get rid of the allocation in pm_qos_add_request()James Bottomley
All current users of pm_qos_add_request() have the ability to supply the memory required by the pm_qos routines, so make them do this and eliminate the kmalloc() with pm_qos_add_request(). This has the double benefit of making the call never fail and allowing it to be called from atomic context. Signed-off-by: James Bottomley <James.Bottomley@suse.de> Signed-off-by: mark gross <markgross@thegnar.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-05-10PM QOS updateMark Gross
This patch changes the string based list management to a handle base implementation to help with the hot path use of pm-qos, it also renames much of the API to use "request" as opposed to "requirement" that was used in the initial implementation. I did this because request more accurately represents what it actually does. Also, I added a string based ABI for users wanting to use a string interface. So if the user writes 0xDDDDDDDD formatted hex it will be accepted by the interface. (someone asked me for it and I don't think it hurts anything.) This patch updates some documentation input I got from Randy. Signed-off-by: markgross <mgross@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2008-08-05pm_qos: spelling fixesRichard Hughes
A documentation cleanup patch. With a minor tweak to clarify units for kbs. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: mark gross <mgross@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05pm qos infrastructure and interfaceMark Gross
The following patch is a generalization of the latency.c implementation done by Arjan last year. It provides infrastructure for more than one parameter, and exposes a user mode interface for processes to register pm_qos expectations of processes. This interface provides a kernel and user mode interface for registering performance expectations by drivers, subsystems and user space applications on one of the parameters. Currently we have {cpu_dma_latency, network_latency, network_throughput} as the initial set of pm_qos parameters. The infrastructure exposes multiple misc device nodes one per implemented parameter. The set of parameters implement is defined by pm_qos_power_init() and pm_qos_params.h. This is done because having the available parameters being runtime configurable or changeable from a driver was seen as too easy to abuse. For each parameter a list of performance requirements is maintained along with an aggregated target value. The aggregated target value is updated with changes to the requirement list or elements of the list. Typically the aggregated target value is simply the max or min of the requirement values held in the parameter list elements. >From kernel mode the use of this interface is simple: pm_qos_add_requirement(param_id, name, target_value): Will insert a named element in the list for that identified PM_QOS parameter with the target value. Upon change to this list the new target is recomputed and any registered notifiers are called only if the target value is now different. pm_qos_update_requirement(param_id, name, new_target_value): Will search the list identified by the param_id for the named list element and then update its target value, calling the notification tree if the aggregated target is changed. with that name is already registered. pm_qos_remove_requirement(param_id, name): Will search the identified list for the named element and remove it, after removal it will update the aggregate target and call the notification tree if the target was changed as a result of removing the named requirement. >From user mode: Only processes can register a pm_qos requirement. To provide for automatic cleanup for process the interface requires the process to register its parameter requirements in the following way: To register the default pm_qos target for the specific parameter, the process must open one of /dev/[cpu_dma_latency, network_latency, network_throughput] As long as the device node is held open that process has a registered requirement on the parameter. The name of the requirement is "process_<PID>" derived from the current->pid from within the open system call. To change the requested target value the process needs to write a s32 value to the open device node. This translates to a pm_qos_update_requirement call. To remove the user mode request for a target value simply close the device node. [akpm@linux-foundation.org: fix warnings] [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: fix build again] [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: mark gross <mgross@linux.intel.com> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: Len Brown <lenb@kernel.org> Cc: Jaroslav Kysela <perex@suse.cz> Cc: Takashi Iwai <tiwai@suse.de> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Venki Pallipadi <venkatesh.pallipadi@intel.com> Cc: Adam Belay <abelay@novell.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>