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* Merge branch 'release' of ↵Linus Torvalds2012-03-311-8/+89
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 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 ...
| * idle, x86: Allow off-lined CPU to enter deeper C statesBoris Ostrovsky2012-03-301-0/+28
| | | | | | | | | | | | | | | | | | | | 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>
| * cpuidle: use the driver's state_count as defaultDaniel Lezcano2012-03-301-1/+1
| | | | | | | | | | | | | | | | | | | | 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>
| * cpuidle: add a sysfs entry to disable specific C state for debug purpose.ShuoX Liu2012-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * cpuidle: Add common time keeping and irq enablingRobert Lee2012-03-211-7/+59
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | cpuidle/tracing: Denote the tracepoints as being in rcu_idle_exit() sectionSteven Rostedt2012-02-131-4/+4
|/ | | | | | | | | | | 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>
* cpu: convert 'cpu' and 'machinecheck' sysdev_class to a regular subsystemKay Sievers2011-12-211-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Merge branch 'release' of ↵Linus Torvalds2011-11-071-58/+28
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux * '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
| * cpuidle: Single/Global registration of idle statesDeepthi Dharwar2011-11-071-33/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * cpuidle: Split cpuidle_state structure and move per-cpu statistics fieldsDeepthi Dharwar2011-11-071-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * cpuidle: Remove CPUIDLE_FLAG_IGNORE and dev->prepare()Deepthi Dharwar2011-11-071-10/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Move dev->last_residency update to driver enter routine; remove ↵Deepthi Dharwar2011-11-071-16/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | dev->last_state 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>
* | cpuidle: Add module.h to drivers/cpuidle files as required.Paul Gortmaker2011-11-011-0/+1
| | | | | | | | Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* | PM QoS: Move and rename the implementation filesJean Pihet2011-08-251-1/+1
|/ | | | | | | | | | | | 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: stop depending on pm_idleLen Brown2011-08-041-20/+18
| | | | | | | | | | | | | | | | | | | 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>
* cpuidle: replace xen access to x86 pm_idle and default_idleLen Brown2011-08-041-0/+4
| | | | | | | | | | | | | | | 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>
* cpuidle: create bootparam "cpuidle.off=1"Len Brown2011-08-041-0/+10
| | | | | | | | | | | | | 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>
* Merge branch 'cpuidle-perf-events' into idle-testLen Brown2011-01-131-2/+8
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| * cpuidle/x86/perf: fix power:cpu_idle double end events and throw cpu_idle ↵Thomas Renninger2011-01-131-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | events from the cpuidle layer 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>
* | Merge branch 'linus' into idle-testLen Brown2011-01-131-1/+2
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| * Merge branch 'for-2.6.38' of ↵Linus Torvalds2011-01-081-1/+1
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu * 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (30 commits) gameport: use this_cpu_read instead of lookup x86: udelay: Use this_cpu_read to avoid address calculation x86: Use this_cpu_inc_return for nmi counter x86: Replace uses of current_cpu_data with this_cpu ops x86: Use this_cpu_ops to optimize code vmstat: User per cpu atomics to avoid interrupt disable / enable irq_work: Use per cpu atomics instead of regular atomics cpuops: Use cmpxchg for xchg to avoid lock semantics x86: this_cpu_cmpxchg and this_cpu_xchg operations percpu: Generic this_cpu_cmpxchg() and this_cpu_xchg support percpu,x86: relocate this_cpu_add_return() and friends connector: Use this_cpu operations xen: Use this_cpu_inc_return taskstats: Use this_cpu_ops random: Use this_cpu_inc_return fs: Use this_cpu_inc_return in buffer.c highmem: Use this_cpu_xx_return() operations vmstat: Use this_cpu_inc_return for vm statistics x86: Support for this_cpu_add, sub, dec, inc_return percpu: Generic support for this_cpu_add, sub, dec, inc_return ... Fixed up conflicts: in arch/x86/kernel/{apic/nmi.c, apic/x2apic_uv_x.c, process.c} as per Tejun.
| | * drivers: Replace __get_cpu_var with __this_cpu_read if not used for an address.Christoph Lameter2010-12-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __get_cpu_var() can be replaced with this_cpu_read and will then use a single read instruction with implied address calculation to access the correct per cpu instance. However, the address of a per cpu variable passed to __this_cpu_read() cannot be determed (since its an implied address conversion through segment prefixes). Therefore apply this only to uses of __get_cpu_var where the addres of the variable is not used. V3->V4: - Move one instance of this_cpu_inc_return to a later patch so that this one can go in without percpu infrastructrure changes. Sedat: fixed compile failure caused by an extra ')'. Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
| * | perf: Clean up power events by introducing new, more generic onesThomas Renninger2011-01-041-0/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add these new power trace events: power:cpu_idle power:cpu_frequency power:machine_suspend The old C-state/idle accounting events: power:power_start power:power_end Have now a replacement (but we are still keeping the old tracepoints for compatibility): power:cpu_idle and power:power_frequency is replaced with: power:cpu_frequency power:machine_suspend is newly introduced. Jean Pihet has a patch integrated into the generic layer (kernel/power/suspend.c) which will make use of it. the type= field got removed from both, it was never used and the type is differed by the event type itself. perf timechart userspace tool gets adjusted in a separate patch. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Jean Pihet <jean.pihet@newoldbits.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: rjw@sisk.pl LKML-Reference: <1294073445-14812-3-git-send-email-trenn@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1290072314-31155-2-git-send-email-trenn@suse.de>
* | cpuidle: delete NOP CPUIDLE_FLAG_POLLLen Brown2011-01-121-1/+1
| | | | | | | | | | | | it serves no purpose Signed-off-by: Len Brown <len.brown@intel.com>
* | cpuidle: Rename X86 specific idle poll state[0] from C0 to POLLThomas Renninger2011-01-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | C0 means and is well know as "not idle". All documentation out there uses this term as "running"/"not idle" state. Also Linux userspace tools (e.g. cpufreq-aperf and turbostat) show C0 residency which there is correct, but means something totally else than cpuidle "POLL" state. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Len Brown <len.brown@intel.com>
* | cpuidle: Make cpuidle_enable_device() call poll_idle_init()Rafael J. Wysocki2011-01-121-41/+41
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | The following scenario is possible with the current cpuidle code and the ACPI cpuidle driver: (1) acpi_processor_cst_has_changed() is called, (2) cpuidle_disable_device() is called, (3) cpuidle_remove_state_sysfs() is called to remove the (presumably outdated) states info from sysfs, (3) acpi_processor_get_power_info() is called, the first entry in the pr->power.states[] table is filled with zeros, (4) acpi_processor_setup_cpuidle() is called and it doesn't fill the first entry in pr->power.states[], (5) cpuidle_enable_device() is called, (6) __cpuidle_register_device() is _not_ called, since the device has already been registered, (7) Consequently, poll_idle_init() is _not_ called either, (8) cpuidle_add_state_sysfs() is called to create the sysfs attributes for the new states and it uses the bogus first table entry from acpi_processor_get_power_info() for creating state0. This problem is avoided if cpuidle_enable_device() unconditionally calls poll_idle_init(). Reported-by: Len Brown <len.brown@intel.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Len Brown <len.brown@intel.com> cc: stable@kernel.org
* cpuidle: extend cpuidle and menu governor to handle dynamic statesAi Li2010-08-101-0/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On some SoC chips, HW resources may be in use during any particular idle period. As a consequence, the cpuidle states that the SoC is safe to enter can change from idle period to idle period. In addition, the latency and threshold of each cpuidle state can vary, depending on the operating condition when the CPU becomes idle, e.g. the current cpu frequency, the current state of the HW blocks, etc. cpuidle core and the menu governor, in the current form, are geared towards cpuidle states that are static, i.e. the availabiltiy of the states, their latencies, their thresholds are non-changing during run time. cpuidle does not provide any hook that cpuidle drivers can use to adjust those values on the fly for the current idle period before the menu governor selects the target cpuidle state. This patch extends cpuidle core and the menu governor to handle states that are dynamic. There are three additions in the patch and the patch maintains backwards-compatibility with existing cpuidle drivers. 1) add prepare() to struct cpuidle_device. A cpuidle driver can hook into the callback and cpuidle will call prepare() before calling the governor's select function. The callback gives the cpuidle driver a chance to update the dynamic information of the cpuidle states for the current idle period, e.g. state availability, latencies, thresholds, power values, etc. 2) add CPUIDLE_FLAG_IGNORE as one of the state flags. In the prepare() function, a cpuidle driver can set/clear the flag to indicate to the menu governor whether a cpuidle state should be ignored, i.e. not available, during the current idle period. 3) add power_specified bit to struct cpuidle_device. The menu governor currently assumes that the cpuidle states are arranged in the order of increasing latency, threshold, and power savings. This is true or can be made true for static states. Once the state parameters are dynamic, the latencies, thresholds, and power savings for the cpuidle states can increase or decrease by different amounts from idle period to idle period. So the assumption of increasing latency, threshold, and power savings from Cn to C(n+1) can no longer be guaranteed. It can be straightforward to calculate the power consumption of each available state and to specify it in power_usage for the idle period. Using the power_usage fields, the menu governor then selects the state that has the lowest power consumption and that still satisfies all other critieria. The power_specified bit defaults to 0. For existing cpuidle drivers, cpuidle detects that power_specified is 0 and fills in a dummy set of power_usage values. Signed-off-by: Ai Li <aili@codeaurora.org> Cc: Len Brown <len.brown@intel.com> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Venkatesh Pallipadi <venki@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [CPUFREQ] x86 cpufreq: Make trace_power_frequency cpufreq driver independentThomas Renninger2010-08-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | and fix the broken case if a core's frequency depends on others. trace_power_frequency was only implemented in a rather ungeneric way in acpi-cpufreq driver's target() function only. -> Move the call to trace_power_frequency to cpufreq.c:cpufreq_notify_transition() where CPUFREQ_POSTCHANGE notifier is triggered. This will support power frequency tracing by all cpufreq drivers trace_power_frequency did not trace frequency changes correctly when the userspace governor was used or when CPU cores' frequency depend on each other. -> Moving this into the CPUFREQ_POSTCHANGE notifier and pass the cpu which gets switched automatically fixes this. Robert Schoene provided some important fixes on top of my initial quick shot version which are integrated in this patch: - Forgot some changes in power_end trace (TP_printk/variable names) - Variable dummy in power_end must now be cpu_id - Use static 64 bit variable instead of unsigned int for cpu_id Signed-off-by: Thomas Renninger <trenn@suse.de> CC: davej@redhat.com CC: arjan@infradead.org CC: linux-kernel@vger.kernel.org CC: robert.schoene@tu-dresden.de Tested-by: robert.schoene@tu-dresden.de Signed-off-by: Dave Jones <davej@redhat.com>
* cpuidle: make cpuidle_curr_driver staticLen Brown2010-05-281-5/+7
| | | | | | | | | | | cpuidle_register_driver() sets cpuidle_curr_driver cpuidle_unregister_driver() clears cpuidle_curr_driver We should't expose cpuidle_curr_driver to potential modification except via these interfaces. So make it static and create cpuidle_get_driver() to observe it. Signed-off-by: Len Brown <len.brown@intel.com>
* cpuidle: always return with interrupts enabledKevin Hilman2009-10-291-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the case where cpuidle_idle_call() returns before changing state due to a need_resched(), it was returning with IRQs disabled. The idle path assumes that the platform specific idle code returns with interrupts enabled (although this too is undocumented AFAICT) and on ARM we have a WARN_ON(!(irqs_disabled()) when returning from the idle loop, so the user-visible effects were only a warning since interrupts were eventually re-enabled later. On x86, this same problem exists, but there is no WARN_ON() to detect it. As on ARM, the interrupts are eventually re-enabled, so I'm not sure of any actual bugs triggered by this. It's primarily a correctness/consistency fix. This patch ensures IRQs are (re)enabled before returning. Reported-by: Hemanth V <hemanthv@ti.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Len Brown <len.brown@intel.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Tested-by: Martin Michlmayr <tbm@cyrius.com> Cc: <stable@kernel.org> [2.6.31.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* tracing, x86, cpuidle: Move the end point of a C state in the power tracerArjan van de Ven2009-09-191-0/+2
| | | | | | | | | | | | | | | | | | | The "end of a C state" trace point currently happens before the code runs that corrects the TSC for having stopped during idle. The result of this is that the timestamp of the end-of-C-state event is garbage on cpus where the TSC stops during idle. This patch moves the end point of the C state to after the timekeeping engine of the kernel has been corrected. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Len Brown <len.brown@intel.com> Cc: fweisbec@gmail.com Cc: peterz@infradead.org Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20090919133533.139c2a46@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* regression: disable timer peek-ahead for 2.6.28Arjan van de Ven2008-11-101-1/+3
| | | | | | | | | | | 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 Fixes: #11826 and #11893 Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'v28-range-hrtimers-for-linus-v2' of ↵Linus Torvalds2008-10-231-0/+7
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'v28-range-hrtimers-for-linus-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (37 commits) hrtimers: add missing docbook comments to struct hrtimer hrtimers: simplify hrtimer_peek_ahead_timers() hrtimers: fix docbook comments DECLARE_PER_CPU needs linux/percpu.h hrtimers: fix typo rangetimers: fix the bug reported by Ingo for real rangetimer: fix BUG_ON reported by Ingo rangetimer: fix x86 build failure for the !HRTIMERS case select: fix alpha OSF wrapper select: fix alpha OSF wrapper hrtimer: peek at the timer queue just before going idle hrtimer: make the futex() system call use the per process slack value hrtimer: make the nanosleep() syscall use the per process slack hrtimer: fix signed/unsigned bug in slack estimator hrtimer: show the timer ranges in /proc/timer_list hrtimer: incorporate feedback from Peter Zijlstra hrtimer: add a hrtimer_start_range() function hrtimer: another build fix hrtimer: fix build bug found by Ingo hrtimer: make select() and poll() use the hrtimer range feature ...
| * hrtimer: peek at the timer queue just before going idleArjan van de Ven2008-09-111-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | As part of going idle, we already look at the time of the next timer event to determine which C-state to select etc. This patch adds functionality that causes the timers that are past their soft expire time, to fire at this time, before we calculate the next wakeup time. This functionality will thus avoid wakeups by running timers before going idle rather than specially waking up for it. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
* | cpuidle: upon BIOS bug, default to default_idle rather than pollingVenkatesh Pallipadi2008-10-171-0/+4
| | | | | | | | | | | | | | http://bugzilla.kernel.org/show_bug.cgi?id=11345 Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
* | cpuidle: use last_state which can reflect the actual state enteredVenkatesh Pallipadi2008-10-161-1/+4
|/ | | | | | | | | | | | | | | | cpuidle accounts the idle time for the C-state it was trying to enter and not to the actual state that the driver eventually entered. The driver may select a different state than the one chosen by cpuidle due to constraints like bus-mastering, etc. Change the time acounting code to look at the dev->last_state after returning from target_state->enter(). Driver can modify dev->last_state internally, inside the enter routine to reflect the actual C-state entered. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Tested-by: Kevin Hilman <khilman@deeprootsystems.com> Signed-off-by: Len Brown <len.brown@intel.com>
* ACPI/CPUIDLE: prevent setting pm_idle to NULLThomas Gleixner2008-07-281-1/+1
| | | | | | | | | | | | | | | | | | pm_idle_save resp. pm_idle_old can be NULL when the restore code in acpi_processor_cst_has_changed() resp. cpuidle_uninstall_idle_handler() is called. This can set pm_idle unconditinally to NULL, which causes the kernel to panic when calling pm_idle in the x86 idle code. This was covered by an extra check for !pm_idle in the x86 idle code, which was removed during the x86 idle code refactoring. Instead of restoring the pm_idle check in the x86 code prevent the acpi/cpuidle code to set pm_idle to NULL. Reported by: Dhaval Giani http://lkml.org/lkml/2008/7/2/309 Based on a debug patch from Ingo Molnar Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* smp_call_function: get rid of the unused nonatomic/retry argumentJens Axboe2008-06-261-1/+1
| | | | | | | | It's never used and the comments refer to nonatomic and retry interchangably. So get rid of it. Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* cpuidle acpi driver: fix oops on AC<->DCVenkatesh Pallipadi2008-06-121-5/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | cpuidle and acpi driver interaction bug with the way cpuidle_register_driver() is called. Due to this bug, there will be oops on AC<->DC on some systems, where they support C-states in one DC and not in AC. The current code does ON BOOT: Look at CST and other C-state info to see whether more than C1 is supported. If it is, then acpi processor_idle does a cpuidle_register_driver() call, which internally enables the device. ON CST change notification (AC<->DC) and on suspend-resume: acpi driver temporarily disables device, updates the device with any new C-states, and reenables the device. The problem is is on boot, there are no C2, C3 states supported and we skip the register. Later on AC<->DC, we may get a CST notification and we try to reevaluate CST and enabled the device, without actually registering it. This causes breakage as we try to create /sys fs sub directory, without the parent directory which is created at register time. Thanks to Sanjeev for reporting the problem here. http://bugzilla.kernel.org/show_bug.cgi?id=10394 Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
* cpuidle: fix 100% C0 statistics regressionVenki Pallipadi2008-03-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | commit 9b12e18cdc1553de62d931e73443c806347cd974 'ACPI: cpuidle: Support C1 idle time accounting' was implicated in a 100% C0 idle regression. http://bugzilla.kernel.org/show_bug.cgi?id=10076 It pointed out a potential problem where the menu governor may get confused by the C-state residency time from poll idle or C1 idle, where this timing info is not accurate. This inaccuracy is due to interrupts being handled before we account for C-state exit. Do not mark TIME_VALID for CO poll state. Mark C1 time as valid only with the MWAIT (CSTATE_FFH) entry method. This makes governors use the timing information only when it is correct and eliminates any wrong policy decisions that may result from invalid timing information. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
* cpuidle: fix cpuidle time and usage overflowYi Yang2008-03-261-1/+1
| | | | | | | | | | | | cpuidle C-state sysfs node time and usage are very easy to overflow because they are all of unsigned int type, time will overflow within about two hours, usage will take longer time to overflow, but they are increasing for ever. This patch will convert them to unsigned long long. Signed-off-by: Yi Yang <yi.y.yang@intel.com> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
* ACPI, cpuidle: Clarify C-state description in sysfsVenkatesh Pallipadi2008-02-141-1/+2
| | | | | | | | | | | | | Add a new sysfs entry under cpuidle states. desc - can be used by driver to communicate to userspace any specific information about the state. This helps in identifying the exact hardware C-states behind the ACPI C-state definition. Idea is to export this through powertop, which will help to map the C-state reported by powertop to actual hardware C-state. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
* cpuidle: build fix for non-x86Venki Pallipadi2008-02-091-1/+12
| | | | | | | | | | | | | | | | | | | | | The last posted version of this patch gave compile error on IA64. So, here goes yet another rewrite of the patch. Convert cpu_idle_wait() to cpuidle_kick_cpus() which is SMP-only, and gives error on non supported CPU. Changes from last patch sent by Kevin: Moved the definition of kick_cpus back to cpuidle.c from cpuidle.h: * Having it in .h gives #error on archs which includes the header file without actually having CPU_IDLE configured. To make it work in .h, we need one more #ifdef around that code which makes it messy. * Also, the function is only called from one file. So, it can be in declared statically in .c rather than making it available to everyone who includes the .h file. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Kevin Hilman <khilman@mvista.com> Signed-off-by: Len Brown <len.brown@intel.com>
* Revert "cpuidle: build fix for non-x86"Len Brown2008-02-071-1/+1
| | | | | This reverts commit f757397097d0713c949af76dccabb65a2785782e. which ironically broke the ia64 build
*-. Merge branches 'release', 'cpuidle-2.6.25' and 'idle' into releaseLen Brown2008-02-071-1/+42
|\ \
| | * cpuidle: Add a poll_idle methodvenkatesh.pallipadi@intel.com2008-02-071-0/+41
| |/ |/| | | | | | | | | | | | | Add a default poll idle state with 0 latency. Provides an option to users to use poll_idle by using 0 as the latency requirement. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
| * cpuidle: build fix for non-x86Kevin Hilman2008-02-011-1/+1
| | | | | | | | | | | | | | | | | | | | Convert cpu_idle_wait() to cpuidle_kick_cpus() macro which is SMP-only, and gives error on non supported CPU. Signed-off-by: Kevin Hilman <khilman@mvista.com> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Len Brown <len.brown@intel.com>
* | pm qos infrastructure and interfaceMark Gross2008-02-051-2/+5
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* cpuidle: remove unused exportsAdrian Bunk2007-10-291-1/+0
| | | | | | | | | | This patch removes the following unused exports: - cpuidle_devices - cpuidle_register_governor - cpuidle_unregister_governor Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Len Brown <len.brown@intel.com>
* cpuidle: consolidate 2.6.22 cpuidle branch into one patchLen Brown2007-10-101-0/+295
commit e5a16b1f9eec0af7cfa0830304b41c1c0833cf9f Author: Len Brown <len.brown@intel.com> Date: Tue Oct 2 23:44:44 2007 -0400 cpuidle: shrink diff processor_idle.c | 440 +++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 429 insertions(+), 11 deletions(-) Signed-off-by: Len Brown <len.brown@intel.com> commit dfbb9d5aedfb18848a3e0d6f6e3e4969febb209c Author: Len Brown <len.brown@intel.com> Date: Wed Sep 26 02:17:55 2007 -0400 cpuidle: reduce diff size Reduces the cpuidle processor_idle.c diff vs 2.6.22 from this processor_idle.c | 2006 ++++++++++++++++++++++++++----------------- 1 file changed, 1219 insertions(+), 787 deletions(-) to this: processor_idle.c | 502 +++++++++++++++++++++++++++++++++++++++---- 1 file changed, 458 insertions(+), 44 deletions(-) ...for the purpose of making the cpuilde patch less invasive and easier to review. no functional changes. build tested only. Signed-off-by: Len Brown <len.brown@intel.com> commit 889172fc915f5a7fe20f35b133cbd205ce69bf6c Author: Venki Pallipadi <venkatesh.pallipadi@intel.com> Date: Thu Sep 13 13:40:05 2007 -0700 cpuidle: Retain old ACPI policy for !CONFIG_CPU_IDLE Retain the old policy in processor_idle, so that when CPU_IDLE is not configured, old C-state policy will still be used. This provides a clean gradual migration path from old ACPI policy to new cpuidle based policy. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit 9544a8181edc7ecc33b3bfd69271571f98ed08bc Author: Venki Pallipadi <venkatesh.pallipadi@intel.com> Date: Thu Sep 13 13:39:17 2007 -0700 cpuidle: Configure governors by default Quoting Len "Do not give an option to users to shoot themselves in the foot". Remove the configurability of ladder and menu governors as they are needed for default policy of cpuidle. That way users will not be able to have cpuidle without any policy loosing all C-state power savings. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit 8975059a2c1e56cfe83d1bcf031bcf4cb39be743 Author: Adam Belay <abelay@novell.com> Date: Tue Aug 21 18:27:07 2007 -0400 CPUIDLE: load ACPI properly when CPUIDLE is disabled Change the registration return codes for when CPUIDLE support is not compiled into the kernel. As a result, the ACPI processor driver will load properly even if CPUIDLE is unavailable. However, it may be possible to cleanup the ACPI processor driver further and eliminate some dead code paths. Signed-off-by: Adam Belay <abelay@novell.com> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit e0322e2b58dd1b12ec669bf84693efe0dc2414a8 Author: Adam Belay <abelay@novell.com> Date: Tue Aug 21 18:26:06 2007 -0400 CPUIDLE: remove cpuidle_get_bm_activity() Remove cpuidle_get_bm_activity() and updates governors accordingly. Signed-off-by: Adam Belay <abelay@novell.com> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit 18a6e770d5c82ba26653e53d240caa617e09e9ab Author: Adam Belay <abelay@novell.com> Date: Tue Aug 21 18:25:58 2007 -0400 CPUIDLE: max_cstate fix Currently max_cstate is limited to 0, resulting in no idle processor power management on ACPI platforms. This patch restores the value to the array size. Signed-off-by: Adam Belay <abelay@novell.com> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit 1fdc0887286179b40ce24bcdbde663172e205ef0 Author: Adam Belay <abelay@novell.com> Date: Tue Aug 21 18:25:40 2007 -0400 CPUIDLE: handle BM detection inside the ACPI Processor driver Update the ACPI processor driver to detect BM activity and limit state entry depth internally, rather than exposing such requirements to CPUIDLE. As a result, CPUIDLE can drop this ACPI-specific interface and become more platform independent. BM activity is now handled much more aggressively than it was in the original implementation, so some testing coverage may be needed to verify that this doesn't introduce any DMA buffer under-run issues. Signed-off-by: Adam Belay <abelay@novell.com> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit 0ef38840db666f48e3cdd2b769da676c57228dd9 Author: Adam Belay <abelay@novell.com> Date: Tue Aug 21 18:25:14 2007 -0400 CPUIDLE: menu governor updates Tweak the menu governor to more effectively handle non-timer break events. Non-timer break events are detected by comparing the actual sleep time to the expected sleep time. In future revisions, it may be more reliable to use the timer data structures directly. Signed-off-by: Adam Belay <abelay@novell.com> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit bb4d74fca63fa96cf3ace644b15ae0f12b7df5a1 Author: Adam Belay <abelay@novell.com> Date: Tue Aug 21 18:24:40 2007 -0400 CPUIDLE: fix 'current_governor' sysfs entry Allow the "current_governor" sysfs entry to properly handle input terminated with '\n'. Signed-off-by: Adam Belay <abelay@novell.com> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit df3c71559bb69b125f1a48971bf0d17f78bbdf47 Author: Len Brown <len.brown@intel.com> Date: Sun Aug 12 02:00:45 2007 -0400 cpuidle: fix IA64 build (again) Signed-off-by: Len Brown <len.brown@intel.com> commit a02064579e3f9530fd31baae16b1fc46b5a7bca8 Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Date: Sun Aug 12 01:39:27 2007 -0400 cpuidle: Remove support for runtime changing of max_cstate Remove support for runtime changeability of max_cstate. Drivers can use use latency APIs. max_cstate can still be used as a boot time option and dmi override. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit 0912a44b13adf22f5e3f607d263aed23b4910d7e Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Date: Sun Aug 12 01:39:16 2007 -0400 cpuidle: Remove ACPI cstate_limit calls from ipw2100 ipw2100 already has code to use accetable_latency interfaces to limit the C-state. Remove the calls to acpi_set_cstate_limit and acpi_get_cstate_limit as they are redundant. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit c649a76e76be6bff1fd770d0a775798813a3f6e0 Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Date: Sun Aug 12 01:35:39 2007 -0400 cpuidle: compile fix for pause and resume functions Fix the compilation failure when cpuidle is not compiled in. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Acked-by: Adam Belay <adam.belay@novell.com> Signed-off-by: Len Brown <len.brown@intel.com> commit 2305a5920fb8ee6ccec1c62ade05aa8351091d71 Author: Adam Belay <abelay@novell.com> Date: Thu Jul 19 00:49:00 2007 -0400 cpuidle: re-write Some portions have been rewritten to make the code cleaner and lighter weight. The following is a list of changes: 1.) the state name is now included in the sysfs interface 2.) detection, hotplug, and available state modifications are handled by CPUIDLE drivers directly 3.) the CPUIDLE idle handler is only ever installed when at least one cpuidle_device is enabled and ready 4.) the menu governor BM code no longer overflows 5.) the sysfs attributes are now printed as unsigned integers, avoiding negative values 6.) a variety of other small cleanups Also, Idle drivers are no longer swappable during runtime through the CPUIDLE sysfs inteface. On i386 and x86_64 most idle handlers (e.g. poll, mwait, halt, etc.) don't benefit from an infrastructure that supports multiple states, so I think using a more general case idle handler selection mechanism would be cleaner. Signed-off-by: Adam Belay <abelay@novell.com> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit df25b6b56955714e6e24b574d88d1fd11f0c3ee5 Author: Len Brown <len.brown@intel.com> Date: Tue Jul 24 17:08:21 2007 -0400 cpuidle: fix IA64 buid Signed-off-by: Len Brown <len.brown@intel.com> commit fd6ada4c14488755ff7068860078c437431fbccd Author: Adrian Bunk <bunk@stusta.de> Date: Mon Jul 9 11:33:13 2007 -0700 cpuidle: static make cpuidle_replace_governor() static Signed-off-by: Adrian Bunk <bunk@stusta.de> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit c1d4a2cebcadf2429c0c72e1d29aa2a9684c32e0 Author: Adrian Bunk <bunk@stusta.de> Date: Tue Jul 3 00:54:40 2007 -0400 cpuidle: static This patch makes the needlessly global struct menu_governor static. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit dbf8780c6e8d572c2c273da97ed1cca7608fd999 Author: Andrew Morton <akpm@linux-foundation.org> Date: Tue Jul 3 00:49:14 2007 -0400 export symbol tick_nohz_get_sleep_length ERROR: "tick_nohz_get_sleep_length" [drivers/cpuidle/governors/menu.ko] undefined! ERROR: "tick_nohz_get_idle_jiffies" [drivers/cpuidle/governors/menu.ko] undefined! And please be sure to get your changes to core kernel suitably reviewed. Cc: Adam Belay <abelay@novell.com> Cc: Venki Pallipadi <venkatesh.pallipadi@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: john stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit 29f0e248e7017be15f99febf9143a2cef00b2961 Author: Andrew Morton <akpm@linux-foundation.org> Date: Tue Jul 3 00:43:04 2007 -0400 tick.h needs hrtimer.h It uses hrtimers. Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit e40cede7d63a029e92712a3fe02faee60cc38fb4 Author: Venki Pallipadi <venkatesh.pallipadi@intel.com> Date: Tue Jul 3 00:40:34 2007 -0400 cpuidle: first round of documentation updates Documentation changes based on Pavel's feedback. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit 83b42be2efece386976507555c29e7773a0dfcd1 Author: Venki Pallipadi <venkatesh.pallipadi@intel.com> Date: Tue Jul 3 00:39:25 2007 -0400 cpuidle: add rating to the governors and pick the one with highest rating by default Introduce a governor rating scheme to pick the right governor by default. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit d2a74b8c5e8f22def4709330d4bfc4a29209b71c Author: Venki Pallipadi <venkatesh.pallipadi@intel.com> Date: Tue Jul 3 00:38:08 2007 -0400 cpuidle: make cpuidle sysfs driver governor switch off by default Make default cpuidle sysfs to show current_governor and current_driver in read-only mode. More elaborate available_governors and available_drivers with writeable current_governor and current_driver interface only appear with "cpuidle_sysfs_switch" boot parameter. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit 1f60a0e80bf83cf6b55c8845bbe5596ed8f6307b Author: Venki Pallipadi <venkatesh.pallipadi@intel.com> Date: Tue Jul 3 00:37:00 2007 -0400 cpuidle: menu governor: change the early break condition Change the C-state early break out algorithm in menu governor. We only look at early breakouts that result in wakeups shorter than idle state's target_residency. If such a breakout is frequent enough, eliminate the particular idle state upto a timeout period. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit 45a42095cf64b003b4a69be3ce7f434f97d7af51 Author: Venki Pallipadi <venkatesh.pallipadi@intel.com> Date: Tue Jul 3 00:35:38 2007 -0400 cpuidle: fix uninitialized variable in sysfs routine Fix the uninitialized usage of ret. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit 80dca7cdba3e6ee13eae277660873ab9584eb3be Author: Venki Pallipadi <venkatesh.pallipadi@intel.com> Date: Tue Jul 3 00:34:16 2007 -0400 cpuidle: reenable /proc/acpi//power interface for the time being Keep /proc/acpi/processor/CPU*/power around for a while as powertop depends on it. It will be marked deprecated and removed in future. powertop can use cpuidle interfaces instead. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit 589c37c2646c5e3813a51255a5ee1159cb4c33fc Author: Venki Pallipadi <venkatesh.pallipadi@intel.com> Date: Tue Jul 3 00:32:37 2007 -0400 cpuidle: menu governor and hrtimer compile fix Compile fix for menu governor. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit 0ba80bd9ab3ed304cb4f19b722e4cc6740588b5e Author: Len Brown <len.brown@intel.com> Date: Thu May 31 22:51:43 2007 -0400 cpuidle: build fix - cpuidle vs ipw2100 module ERROR: "acpi_set_cstate_limit" [drivers/net/wireless/ipw2100.ko] undefined! Signed-off-by: Len Brown <len.brown@intel.com> commit d7d8fa7f96a7f7682be7c6cc0cc53fa7a18c3b58 Author: Adam Belay <abelay@novell.com> Date: Sat Mar 24 03:47:07 2007 -0400 cpuidle: add the 'menu' governor Here is my first take at implementing an idle PM governor that takes full advantage of NO_HZ. I call it the 'menu' governor because it considers the full list of idle states before each entry. I've kept the implementation fairly simple. It attempts to guess the next residency time and then chooses a state that would meet at least the break-even point between power savings and entry cost. To this end, it selects the deepest idle state that satisfies the following constraints: 1. If the idle time elapsed since bus master activity was detected is below a threshold (currently 20 ms), then limit the selection to C2-type or above. 2. Do not choose a state with a break-even residency that exceeds the expected time remaining until the next timer interrupt. 3. Do not choose a state with a break-even residency that exceeds the elapsed time between the last pair of break events, excluding timer interrupts. This governor has an advantage over "ladder" governor because it proactively checks how much time remains until the next timer interrupt using the tick infrastructure. Also, it handles device interrupt activity more intelligently by not including timer interrupts in break event calculations. Finally, it doesn't make policy decisions using the number of state entries, which can have variable residency times (NO_HZ makes these potentially very large), and instead only considers sleep time deltas. The menu governor can be selected during runtime using the cpuidle sysfs interface like so: "echo "menu" > /sys/devices/system/cpu/cpuidle/current_governor" Signed-off-by: Adam Belay <abelay@novell.com> Signed-off-by: Len Brown <len.brown@intel.com> commit a4bec7e65aa3b7488b879d971651cc99a6c410fe Author: Adam Belay <abelay@novell.com> Date: Sat Mar 24 03:47:03 2007 -0400 cpuidle: export time until next timer interrupt using NO_HZ Expose information about the time remaining until the next timer interrupt expires by utilizing the dynticks infrastructure. Also modify the main idle loop to allow dynticks to handle non-interrupt break events (e.g. DMA). Finally, expose sleep ticks information to external code. Thomas Gleixner is responsible for much of the code in this patch. However, I've made some additional changes, so I'm probably responsible if there are any bugs or oversights :) Signed-off-by: Adam Belay <abelay@novell.com> Signed-off-by: Len Brown <len.brown@intel.com> commit 2929d8996fbc77f41a5ff86bb67cdde3ca7d2d72 Author: Adam Belay <abelay@novell.com> Date: Sat Mar 24 03:46:58 2007 -0400 cpuidle: governor API changes This patch prepares cpuidle for the menu governor. It adds an optional stage after idle state entry to give the governor an opportunity to check why the state was exited. Also it makes sure the idle loop returns after each state entry, allowing the appropriate dynticks code to run. Signed-off-by: Adam Belay <abelay@novell.com> Signed-off-by: Len Brown <len.brown@intel.com> commit 3a7fd42f9825c3b03e364ca59baa751bb350775f Author: Venki Pallipadi <venkatesh.pallipadi@intel.com> Date: Thu Apr 26 00:03:59 2007 -0700 cpuidle: hang fix Prevent hang on x86-64, when ACPI processor driver is added as a module on a system that does not support C-states. x86-64 expects all idle handlers to enable interrupts before returning from idle handler. This is due to enter_idle(), exit_idle() races. Make cpuidle_idle_call() confirm to this when there is no pm_idle_old. Also, cpuidle look at the return values of attch_driver() and set current_driver to NULL if attach fails on all CPUs. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit 4893339a142afbd5b7c01ffadfd53d14746e858e Author: Shaohua Li <shaohua.li@intel.com> Date: Thu Apr 26 10:40:09 2007 +0800 cpuidle: add support for max_cstate limit With CPUIDLE framework, the max_cstate (to limit max cpu c-state) parameter is ingored. Some systems require it to ignore C2/C3 and some drivers like ipw require it too. Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit 43bbbbe1cb998cbd2df656f55bb3bfe30f30e7d1 Author: Shaohua Li <shaohua.li@intel.com> Date: Thu Apr 26 10:40:13 2007 +0800 cpuidle: add cpuidle_fore_redetect_devices API add cpuidle_force_redetect_devices API, which forces all CPU redetect idle states. Next patch will use it. Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit d1edadd608f24836def5ec483d2edccfb37b1d19 Author: Shaohua Li <shaohua.li@intel.com> Date: Thu Apr 26 10:40:01 2007 +0800 cpuidle: fix sysfs related issue Fix the cpuidle sysfs issue. a. make kobject dynamicaly allocated b. fixed sysfs init issue to avoid suspend/resume issue Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit 7169a5cc0d67b263978859672e86c13c23a5570d Author: Randy Dunlap <randy.dunlap@oracle.com> Date: Wed Mar 28 22:52:53 2007 -0400 cpuidle: 1-bit field must be unsigned A 1-bit bitfield has no room for a sign bit. drivers/cpuidle/governors/ladder.c:54:16: error: dubious bitfield without explicit `signed' or `unsigned' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit 4658620158dc2fbd9e4bcb213c5b6fb5d05ba7d4 Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Date: Wed Mar 28 22:52:41 2007 -0400 cpuidle: fix boot hang Patch for cpuidle boot hang reported by Larry Finger here. http://www.ussg.iu.edu/hypermail/linux/kernel/0703.2/2025.html Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Larry Finger <larry.finger@lwfinger.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit c17e168aa6e5fe3851baaae8df2fbc1cf11443a9 Author: Len Brown <len.brown@intel.com> Date: Wed Mar 7 04:37:53 2007 -0500 cpuidle: ladder does not depend on ACPI build fix for CONFIG_ACPI=n In file included from drivers/cpuidle/governors/ladder.c:21: include/acpi/processor.h:88: error: expected specifier-qualifier-list before ‘acpi_integer’ include/acpi/processor.h:106: error: expected specifier-qualifier-list before ‘acpi_integer’ include/acpi/processor.h:168: error: expected specifier-qualifier-list before ‘acpi_handle’ Signed-off-by: Len Brown <len.brown@intel.com> commit 8c91d958246bde68db0c3f0c57b535962ce861cb Author: Adrian Bunk <bunk@stusta.de> Date: Tue Mar 6 02:29:40 2007 -0800 cpuidle: make code static This patch makes the following needlessly global code static: - driver.c: __cpuidle_find_driver() - governor.c: __cpuidle_find_governor() - ladder.c: struct ladder_governor Signed-off-by: Adrian Bunk <bunk@stusta.de> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Adam Belay <abelay@novell.com> Cc: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit 0c39dc3187094c72c33ab65a64d2017b21f372d2 Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Date: Wed Mar 7 02:38:22 2007 -0500 cpu_idle: fix build break This patch fixes a build breakage with !CONFIG_HOTPLUG_CPU and CONFIG_CPU_IDLE. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit 8112e3b115659b07df340ef170515799c0105f82 Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Date: Tue Mar 6 02:29:39 2007 -0800 cpuidle: build fix for !CPU_IDLE Fix the compile issues when CPU_IDLE is not configured. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Adam Belay <abelay@novell.com> Cc: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com> commit 1eb4431e9599cd25e0d9872f3c2c8986821839dd Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Date: Thu Feb 22 13:54:57 2007 -0800 cpuidle take2: Basic documentation for cpuidle Documentation for cpuidle infrastructure Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Adam Belay <abelay@novell.com> Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> commit ef5f15a8b79123a047285ec2e3899108661df779 Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Date: Thu Feb 22 13:54:03 2007 -0800 cpuidle take2: Hookup ACPI C-states driver with cpuidle Hookup ACPI C-states onto generic cpuidle infrastructure. drivers/acpi/procesor_idle.c is now a ACPI C-states driver that registers as a driver in cpuidle infrastructure and the policy part is removed from drivers/acpi/processor_idle.c. We use governor in cpuidle instead. Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Adam Belay <abelay@novell.com> Signed-off-by: Len Brown <len.brown@intel.com> commit 987196fa82d4db52c407e8c9d5dec884ba602183 Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Date: Thu Feb 22 13:52:57 2007 -0800 cpuidle take2: Core cpuidle infrastructure Announcing 'cpuidle', a new CPU power management infrastructure to manage idle CPUs in a clean and efficient manner. cpuidle separates out the drivers that can provide support for multiple types of idle states and policy governors that decide on what idle state to use at run time. A cpuidle driver can support multiple idle states based on parameters like varying power consumption, wakeup latency, etc (ACPI C-states for example). A cpuidle governor can be usage model specific (laptop, server, laptop on battery etc). Main advantage of the infrastructure being, it allows independent development of drivers and governors and allows for better CPU power management. A huge thanks to Adam Belay and Shaohua Li who were part of this mini-project since its beginning and are greatly responsible for this patchset. This patch: Core cpuidle infrastructure. Introduces a new abstraction layer for cpuidle: * which manages drivers that can support multiple idles states. Drivers can be generic or particular to specific hardware/platform * allows pluging in multiple policy governors that can take idle state policy decision * The core also has a set of sysfs interfaces with which administrato can know about supported drivers and governors and switch them at run time. Signed-off-by: Adam Belay <abelay@novell.com> Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>