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* Merge branch 'cpuidle-perf-events' into idle-testLen Brown2011-01-121-2/+8
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| * cpuidle/x86/perf: fix power:cpu_idle double end events and throw cpu_idle ↵Thomas Renninger2011-01-121-2/+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 Brown2011-01-121-1/+2
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| * Merge branch 'for-2.6.38' of ↵Linus Torvalds2011-01-071-1/+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: Fix typosLucas De Marchi2010-09-281-1/+1
| | | | Signed-off-by: Len Brown <len.brown@intel.com>
* cpuidle: extend cpuidle and menu governor to handle dynamic statesAi Li2010-08-092-7/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* sched: Cure nr_iowait_cpu() usersPeter Zijlstra2010-07-011-2/+2
| | | | | | | | | | | | | | | | | | | | | | | Commit 0224cf4c5e (sched: Intoduce get_cpu_iowait_time_us()) broke things by not making sure preemption was indeed disabled by the callers of nr_iowait_cpu() which took the iowait value of the current cpu. This resulted in a heap of preempt warnings. Cure this by making nr_iowait_cpu() take a cpu number and fix up the callers to pass in the right number. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Maxim Levitsky <maximlevitsky@gmail.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Jiri Slaby <jslaby@suse.cz> Cc: linux-pm@lists.linux-foundation.org LKML-Reference: <1277968037.1868.120.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge branch 'idle-release' of ↵Linus Torvalds2010-05-284-10/+24
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6 * 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6: intel_idle: native hardware cpuidle driver for latest Intel processors ACPI: acpi_idle: touch TS_POLLING only in the non-MWAIT case acpi_pad: uses MONITOR/MWAIT, so it doesn't need to clear TS_POLLING sched: clarify commment for TS_POLLING ACPI: allow a native cpuidle driver to displace ACPI cpuidle: make cpuidle_curr_driver static cpuidle: add cpuidle_unregister_driver() error check cpuidle: fail to register if !CONFIG_CPU_IDLE
| * cpuidle: make cpuidle_curr_driver staticLen Brown2010-05-274-9/+20
| | | | | | | | | | | | | | | | | | | | | | 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: add cpuidle_unregister_driver() error checkLen Brown2010-05-271-1/+4
| | | | | | | | | | | | | | Assure that cpuidle_unregister_driver() will not clobber the registered driver if unregistered by somebody else. Signed-off-by: Len Brown <len.brown@intel.com>
* | cpuidle: add a repeating pattern detector to the menu governorArjan van de Ven2010-05-251-1/+59
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the menu governor uses the (corrected) next timer as key item for predicting the idle duration. It turns out that there are specific cases where this breaks down: There are cases where we have a very repetitive pattern of idle durations, where the idle period is pretty much the same, for reasons completely unrelated to the next timer event. Examples of such repeating patterns are network loads with irq mitigation, the mouse moving but in theory also the wifi beacons. This patch adds a relatively simple detector for such repeating patterns, where the standard deviation of the last 8 idle periods is compared to a threshold. With this extra predictor in place, measurements show that the DECAY factor can now be increased (the decaying average will now decay slower) to get an even more stable result. [arjan@infradead.org: fix bug identified by Frank] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Corrado Zoccolo <czoccolo@gmail.com> Cc: Frank Rowand <frank.rowand@am.sony.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | PM QOS updateMark Gross2010-05-102-2/+2
|/ | | | | | | | | | | | | | | | | | 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>
* cpuidle: Fix incorrect optimizationArjan van de Ven2010-05-091-5/+4
| | | | | | | | | | | | | | | | | | | commit 672917dcc78 ("cpuidle: menu governor: reduce latency on exit") added an optimization, where the analysis on the past idle period moved from the end of idle, to the beginning of the new idle. Unfortunately, this optimization had a bug where it zeroed one key variable for new use, that is needed for the analysis. The fix is simple, zero the variable after doing the work from the previous idle. During the audit of the code that found this issue, another issue was also found; the ->measured_us data structure member is never set, a local variable is always used instead. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Corrado Zoccolo <czoccolo@gmail.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* Driver core: Constify struct sysfs_ops in struct kobj_typeEmese Revfy2010-03-071-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Constify struct sysfs_ops. This is part of the ops structure constification effort started by Arjan van de Ven et al. Benefits of this constification: * prevents modification of data that is shared (referenced) by many other structure instances at runtime * detects/prevents accidental (but not intentional) modification attempts on archs that enforce read-only kernel data at runtime * potentially better optimized code as the compiler can assume that the const data cannot be changed * the compiler/linker move const data into .rodata and therefore exclude them from false sharing Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: David Teigland <teigland@redhat.com> Acked-by: Matt Domsch <Matt_Domsch@dell.com> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Acked-by: Hans J. Koch <hjk@linutronix.de> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Jens Axboe <jens.axboe@oracle.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysdev: Pass attribute in sysdev_class attributes show/storeAndi Kleen2010-03-071-0/+4
| | | | | | | | | | | | | | | | | | | | | | | Passing the attribute to the low level IO functions allows all kinds of cleanups, by sharing low level IO code without requiring an own function for every piece of data. Also drivers can extend the attributes with own data fields and use that in the low level function. Similar to sysdev_attributes and normal attributes. This is a tree-wide sweep, converting everything in one go. No functional changes in this patch other than passing the new argument everywhere. Tested on x86, the non x86 parts are uncompiled. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* cpuidle menu: remove 8 bytes of padding on 64 bit buildsRichard Kennedy2010-03-061-1/+1
| | | | | | | | | | | Reorder struct menu_device to remove 8 bytes of padding on 64 bit builds. Size drops from 136 to 128 bytes, so possibly needing one fewer cache lines. Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk> Cc: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* drivers/cpuidle/governors/menu.c: fix undefined reference to `__udivdi3'Stephen Hemminger2010-01-111-3/+9
| | | | | | | | | | | | | | | menu: use proper 64 bit math The new menu governor is incorrectly doing a 64 bit divide. Compile tested only Signed-off-by: Stephen Hemminger <shemminger@vyatta.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: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* drivers/cpuidle: Move dereference after NULL testJulia Lawall2009-12-151-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | It does not seem possible that ldev can be NULL, so drop the unnecessary test. If ldev can somehow be NULL, then the initialization of last_idx should be moved below the test. A simplified version of the semantic match that detects this problem is as follows (http://coccinelle.lip6.fr/): // <smpl> @match exists@ expression x, E; identifier fld; @@ * x->fld ... when != \(x = E\|&x\) * x == NULL // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* tree-wide: fix typos "aquire" -> "acquire", "cumsumed" -> "consumed"Uwe Kleine-König2009-11-091-2/+2
| | | | | | | | | | | This patch was generated by git grep -E -i -l '[Aa]quire' | xargs -r perl -p -i -e 's/([Aa])quire/$1cquire/' and the cumsumed was found by checking the diff for aquire. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* 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>
* cpuidle: menu governor: reduce latency on exitCorrado Zoccolo2009-09-221-1/+19
| | | | | | | | | | | | | | | | | | | | | Move the state residency accounting and statistics computation off the hot exit path. On exit, the need to recompute statistics is recorded, and new statistics will be computed when menu_select is called again. The expected effect is to reduce processor wakeup latency from sleep (C-states). We are speaking of few hundreds of cycles reduction out of a several microseconds latency (determined by the hardware transition), so it is difficult to measure. Signed-off-by: Corrado Zoccolo <czoccolo@gmail.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Len Brown <len.brown@intel.com> Cc: Adam Belay <abelay@novell.com Acked-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* cpuidle: fix the menu governor to boost IO performanceArjan van de Ven2009-09-221-39/+212
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix the menu idle governor which balances power savings, energy efficiency and performance impact. The reason for a reworked governor is that there have been serious performance issues reported with the existing code on Nehalem server systems. To show this I'm sure Andrew wants to see benchmark results: (benchmark is "fio", "no cstates" is using "idle=poll") no cstates current linux new algorithm 1 disk 107 Mb/s 85 Mb/s 105 Mb/s 2 disks 215 Mb/s 123 Mb/s 209 Mb/s 12 disks 590 Mb/s 320 Mb/s 585 Mb/s In various power benchmark measurements, no degredation was found by our measurement&diagnostics team. Obviously a small percentage more power was used in the "fio" benchmark, due to the much higher performance. While it would be a novel idea to describe the new algorithm in this commit message, I cheaped out and described it in comments in the code instead. [changes since first post: spelling fixes from akpm, review feedback, folded menu-tng into menu.c] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Len Brown <lenb@kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> 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>
* cpuidle: Add decaying history logic to menu idle predictorPallipadi, Venkatesh2008-12-301-1/+9
| | | | | | | | | | | | | Add decaying history of predicted idle time, instead of using the last early wakeup. This logic helps menu governor do better job of predicting idle time. With this change, we also measured noticable (~8%) power savings on a DP server system with CPUs supporting deep C states, when system was lightly loaded. There was no change to power or perf on other load conditions. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
* regression: disable timer peek-ahead for 2.6.28Arjan van de Ven2008-11-091-1/+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 Pallipadi2008-10-161-0/+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>
* cpuidle: Make ladder governor honor latency requirements fullyvenkatesh.pallipadi@intel.com2008-08-151-0/+12
| | | | | | | | | ladder governor only honored latency requirement when promoting C-states. Instead. it should check for latency requirement on each idle call, and demote to appropriate C-state when there is a latency requirement change. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com>
* cpuidle: Menu governor fix wrong usage of measured_usvenkatesh.pallipadi@intel.com2008-08-151-12/+19
| | | | | | | | | | | | | | | | | | There is a bug in menu governor where we have if (data->elapsed_us < data->elapsed_us + measured_us) with measured_us already having elapsed_us added in tickless case here unsigned int measured_us = cpuidle_get_last_residency(dev) + data->elapsed_us; Also, it should be last_residency, not measured_us, that need to be used to do comparing and distinguish between expected & non-expected events. Refactor menu_reflect() to fix these two problems. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Wei Gang <gang.wei@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com>
* cpuidle: Do not use poll_idle unless user asks for itvenkatesh.pallipadi@intel.com2008-08-152-6/+19
| | | | | | | | | | | | | | poll_idle was added to CPUIDLE, just as a low latency idle handler, to be used in cases when user desires CPUs not to enter any idle state at all. It was supposed to be a run time idle=poll option to the user. But, it was indeed getting used during normal menu and ladder governor default case, with no special user setting (Reported by Linus Torvalds). Change below ensures that poll_idle will not be used unless user explicitly asks pm_qos infrastructure for zero latency requirement. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com>
* cpuidle: make sysfs attributes sysdev class attributesRabin Vincent2008-08-121-14/+15
| | | | | | | | | | | | | | | | These attributes are really sysdev class attributes. The incorrect definition leads to an oops because of recent changes which make sysdev attributes use a different prototype. Based on Andi's f718cd4add5aea9d379faff92f162571e356cc5f ("sched: make scheduler sysfs attributes sysdev class devices") Reported-by: Eric Sesterhenn <snakebyte@gmx.de> Signed-off-by: Rabin Vincent <rabin@rab.in> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: "Li, Shaohua" <shaohua.li@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 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>
* sysdev: Pass the attribute to the low level sysdev show/store functionAndi Kleen2008-07-211-3/+7
| | | | | | | | | | | | | | | | | | | | | | This allow to dynamically generate attributes and share show/store functions between attributes. Right now most attributes are generated by special macros and lots of duplicated code. With the attribute passed it's instead possible to attach some data to the attribute and then use that in shared low level functions to do different things. I need this for the dynamically generated bank attributes in the x86 machine check code, but it'll allow some further cleanups. I converted all users in tree to the new show/store prototype. It's a single huge patch to avoid unbisectable sections. Runtime tested: x86-32, x86-64 Compiled only: ia64, powerpc Not compile tested/only grep converted: sh, arm, avr32 Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 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 Pallipadi2008-06-111-5/+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 Yang2008-03-262-3/+9
| | | | | | | | | | | | 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 Pallipadi2008-02-142-4/+13
| | | | | | | | | | | | | 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 Brown2008-02-072-3/+44
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