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* Merge commit 'v2.6.34-rc6' into x86/cpuH. Peter Anvin2010-05-081-2/+6
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| * [CPUFREQ] use max load in conservative governorDominik Brodowski2010-03-311-2/+6
| | | | | | | | | | | | | | | | | | Instead of using the load of the last CPU in a package, use the maximum load of all CPUs in a package. Reported-by: Jean-Christian Goussard <jeanchristian.goussard@sfr.fr> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Dave Jones <davej@redhat.com>
* | cpufreq: Unify sysfs attribute definition macrosBorislav Petkov2010-04-091-32/+16
|/ | | | | | | | | | | Multiple modules used to define those which are with identical functionality and were needlessly replicated among the different cpufreq drivers. Push them into the header and remove duplication. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> LKML-Reference: <1270065406-1814-7-git-send-email-bp@amd64.org> Reviewed-by: Thomas Renninger <trenn@suse.de> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* [CPUFREQ] Use global sysfs cpufreq structure for conservative governor tuningsThomas Renninger2009-11-241-19/+110
| | | | | | | Same adustments that have been added to the ondemand recently. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] Resolve time unit thinko in ondemand/conservative govsPallipadi, Venkatesh2009-11-171-2/+2
| | | | | | | | | | | | | | | | | ondemand and conservative governors are messing up time units in the code path where NO_HZ is not enabled and ignore_nice is set. The walltime idletime stored is in jiffies and nice time calculation is happening in microseconds. The problem was reported and diagnosed by Alexander here. http://marc.info/?l=linux-kernel&m=125752550404513&w=2 The patch below fixes this thinko. Reported-by: Alexander Miller <Miller@fmi.uni-stuttgart.de> Tested-by: Alexander Miller <Miller@fmi.uni-stuttgart.de> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
* Merge branch 'percpu-for-linus' into percpu-for-nextTejun Heo2009-08-141-25/+18
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: arch/sparc/kernel/smp_64.c arch/x86/kernel/cpu/perf_counter.c arch/x86/kernel/setup_percpu.c drivers/cpufreq/cpufreq_ondemand.c mm/percpu.c Conflicts in core and arch percpu codes are mostly from commit ed78e1e078dd44249f88b1dd8c76dafb39567161 which substituted many num_possible_cpus() with nr_cpu_ids. As for-next branch has moved all the first chunk allocators into mm/percpu.c, the changes are moved from arch code to mm/percpu.c. Signed-off-by: Tejun Heo <tj@kernel.org>
| * [CPUFREQ] Fix NULL pointer dereference regression in conservative governorPallipadi, Venkatesh2009-08-041-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit ee88415caf736b89500f16e0a545614541a45005 introduced this regression when it removed enable bit in cpu_dbs_info_s. That added a possibility of dbs_cpufreq_notifier getting called for a CPU that is not yet managed by conservative governor. That will happen as the transition notifier is set as soon as one CPU switches to conservative governor and other CPUs can get a NULL pointer dereference without the enable bit check. Add the enable bit back again. Reported-by: Lermytte Christophe <Christophe.Lermytte@thomson.net> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
| * [CPUFREQ] Cleanup locking in conservative governorvenkatesh.pallipadi@intel.com2009-07-061-21/+13
| | | | | | | | | | | | | | | | | | Redesign the locking inside conservative driver. Make dbs_mutex handle all the global state changes inside the driver and invent a new percpu mutex to serialize percpu timer and frequency limit change. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
| * [CPUFREQ] Eliminate the recent lockdep warnings in cpufreqvenkatesh.pallipadi@intel.com2009-07-061-16/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit b14893a62c73af0eca414cfed505b8c09efc613c although it was very much needed to properly cleanup ondemand timer, opened-up a can of worms related to locking dependencies in cpufreq. Patch here defines the need for dbs_mutex and cleans up its usage in ondemand governor. This also resolves the lockdep warnings reported here http://lkml.indiana.edu/hypermail/linux/kernel/0906.1/01925.html http://lkml.indiana.edu/hypermail/linux/kernel/0907.0/00820.html and few others.. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
* | percpu: clean up percpu variable definitionsTejun Heo2009-06-241-6/+6
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Percpu variable definition is about to be updated such that all percpu symbols including the static ones must be unique. Update percpu variable definitions accordingly. * as,cfq: rename ioc_count uniquely * cpufreq: rename cpu_dbs_info uniquely * xen: move nesting_count out of xen_evtchn_do_upcall() and rename it * mm: move ratelimits out of balance_dirty_pages_ratelimited_nr() and rename it * ipv4,6: rename cookie_scratch uniquely * x86 perf_counter: rename prev_left to pmc_prev_left, irq_entry to pmc_irq_entry and nmi_entry to pmc_nmi_entry * perf_counter: rename disable_count to perf_disable_count * ftrace: rename test_event_disable to ftrace_test_event_disable * kmemleak: rename test_pointer to kmemleak_test_pointer * mce: rename next_interval to mce_next_interval [ Impact: percpu usage cleanups, no duplicate static percpu var names ] Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Dave Jones <davej@redhat.com> Cc: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: linux-mm <linux-mm@kvack.org> Cc: David S. Miller <davem@davemloft.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <srostedt@redhat.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Andi Kleen <andi@firstfloor.org>
* [CPUFREQ] Only set sampling_rate_max deprecated, sampling_rate_min is usefulThomas Renninger2009-06-151-15/+2
| | | | | | | | Update the documentation accordingly. Cleanup and use printk_once. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] ondemand: Uncouple minimal sampling rate from HZ in NO_HZ caseThomas Renninger2009-06-151-26/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | With this patch you have following minimal sampling rate restrictions: Kernel restrictions: If CONFIG_NO_HZ is set, the limit is 10ms fixed. If CONFIG_NO_HZ is not set or no_hz=off boot parameter is used, the limits depend on the CONFIG_HZ option: HZ=1000: min=20000us (20ms) HZ=250: min=80000us (80ms) HZ=100: min=200000us (200ms) HW restrictions: Do not sample/poll more often than HW latency * 100 exported by the low level cpufreq HW driver The higher value of above restrictions is the minimal sampling rate that can be set (and can be seen via ondemand/sampling_rate_min sysfs file) Default sampling rate still is HW latency * 1000, but this will now end up in lower values on latest (Intel and AMD) hardware as these can switch really fast and sampling rate mostly was limited to the 80ms or 200ms (depending on whether HZ=250 or HZ=1000 is used). Signed-off-by: Thomas Renninger <trenn@suse.de> Cc: Pallipadi Venkatesh <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] fix timer teardown in conservative governorMathieu Desnoyers2009-05-261-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * Rafael J. Wysocki (rjw@sisk.pl) wrote: > This message has been generated automatically as a part of a report > of regressions introduced between 2.6.28 and 2.6.29. > > The following bug entry is on the current list of known regressions > introduced between 2.6.28 and 2.6.29. Please verify if it still should > be listed and let me know (either way). > > > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=13186 > Subject : cpufreq timer teardown problem > Submitter : Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> > Date : 2009-04-23 14:00 (24 days old) > References : http://marc.info/?l=linux-kernel&m=124049523515036&w=4 > Handled-By : Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> > Patch : http://patchwork.kernel.org/patch/19754/ > http://patchwork.kernel.org/patch/19753/ > (re-send with updated changelog) cpufreq fix timer teardown in conservative governor The problem is that dbs_timer_exit() uses cancel_delayed_work() when it should use cancel_delayed_work_sync(). cancel_delayed_work() does not wait for the workqueue handler to exit. The ondemand governor does not seem to be affected because the "if (!dbs_info->enable)" check at the beginning of the workqueue handler returns immediately without rescheduling the work. The conservative governor in 2.6.30-rc has the same check as the ondemand governor, which makes things usually run smoothly. However, if the governor is quickly stopped and then started, this could lead to the following race : dbs_enable could be reenabled and multiple do_dbs_timer handlers would run. This is why a synchronized teardown is required. Depends on patch cpufreq: remove rwsem lock from CPUFREQ_GOV_STOP call The following patch applies to 2.6.30-rc2. Stable kernels have a similar issue which should also be fixed, but the code changed between 2.6.29 and 2.6.30, so this patch only applies to 2.6.30-rc. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> CC: Andrew Morton <akpm@linux-foundation.org> CC: gregkh@suse.de CC: stable@kernel.org CC: cpufreq@vger.kernel.org CC: Ingo Molnar <mingo@elte.hu> CC: rjw@sisk.pl CC: Ben Slusky <sluskyb@paranoiacs.org> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] conservative: remove 10x from def_sampling_rateAlexander Clouter2009-02-241-1/+1
| | | | | | | | | | AMD users get particular hit by this issue (bug 8081) as it caps at typically 90 seconds as the minimum period for a frequency change. Harsh eh? Years ago I borked this buy puting the 10x in the wrong place...I fix that by removing it altogether. Signed-off-by: Alexander Clouter <alex@digriz.org.uk> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] conservative: fixup governor to function more like ondemand logicAlexander Clouter2009-02-241-140/+188
| | | | | | | | As conservative is based off ondemand the codebases occasionally need to be resync'd. This patch, although ugly, does this. Signed-off-by: Alexander Clouter <alex@digriz.org.uk> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] conservative: fix dbs_cpufreq_notifier so freq is not lockedAlexander Clouter2009-02-241-1/+12
| | | | | | | | | | | | When someone added the dbs_cpufreq_notifier section to the governor the code ended up causing the frequency to only fall. This is because requested_freq is tinkered with and that should only modified if it has an invlaid value due to changes in the available frequency ranges This should fix #10055. Signed-off-by: Alexander Clouter <alex@digriz.org.uk> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] conservative: amend author's email addressAlexander Clouter2009-02-241-2/+2
| | | | | | | Amend author's email address. Signed-off-by: Alexander Clouter <alex@digriz.org.uk> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] ondemand/conservative: sanitize sampling_rate restrictionsThomas Renninger2009-02-241-10/+18
| | | | | | | | Limit sampling rate to transition_latency * 100 or kernel limits. If sampling_rate is tried to be set too low, set the lowest allowed value. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] ondemand/conservative: deprecate sampling_rate{min,max}Thomas Renninger2009-02-241-0/+15
| | | | | | | The same info can be obtained via the transition_latency sysfs file Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] checkpatch cleanups for conservative governorDave Jones2009-02-241-13/+15
| | | | Signed-off-by: Dave Jones <davej@redhat.com>
* cpumask: convert struct cpufreq_policy to cpumask_var_tRusty Russell2009-01-061-1/+1
| | | | | | | | | | | | | | Impact: use new cpumask API to reduce memory usage This is part of an effort to reduce structure sizes for machines configured with large NR_CPUS. cpumask_t gets replaced by cpumask_var_t, which is either struct cpumask[1] (small NR_CPUS) or struct cpumask * (large NR_CPUS). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Mike Travis <travis@sgi.com> Acked-by: Dave Jones <davej@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* [CPUFREQ] Don't export governors for default governorSven Wegener2008-10-091-1/+3
| | | | | | | | | | | | | | | | | We don't need to export the governors for use as the default governor, because the default governor will be built-in anyway and we can access the symbol directly. This also fixes the following sparse warnings: drivers/cpufreq/cpufreq_conservative.c:578:25: warning: symbol 'cpufreq_gov_conservative' was not declared. Should it be static? drivers/cpufreq/cpufreq_ondemand.c:582:25: warning: symbol 'cpufreq_gov_ondemand' was not declared. Should it be static? drivers/cpufreq/cpufreq_performance.c:39:25: warning: symbol 'cpufreq_gov_performance' was not declared. Should it be static? drivers/cpufreq/cpufreq_powersave.c:38:25: warning: symbol 'cpufreq_gov_powersave' was not declared. Should it be static? drivers/cpufreq/cpufreq_userspace.c:190:25: warning: symbol 'cpufreq_gov_userspace' was not declared. Should it be static? Signed-off-by: Sven Wegener <sven.wegener@stealer.net> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] use deferrable delayed work init in conservative governorBen Slusky2008-10-091-0/+1
| | | | | | | | | | Venki Pallipadi made a similar change to the ondemand governor a while back (in commit 28287033e12463c8ff89f1ea8038783d0360391c). It seems to work just as well in the conservative governor, leading to fewer wakeups as reported by powertop. Signed-off-by: Ben Slusky <sluskyb@paranoiacs.org> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] Fix -Wshadow warning in conservative governor.Dave Jones2008-08-081-10/+10
| | | | | | | | drivers/cpufreq/cpufreq_conservative.c:336:15: warning: symbol 'freq_step' shadows an earlier one Just rename the local variable. Signed-off-by: Dave Jones <davej@redhat.com>
* cpufreq: use performance variant for_each_cpu_mask_nrMike Travis2008-05-231-1/+1
| | | | | | | | | | | | Change references from for_each_cpu_mask to for_each_cpu_mask_nr where appropriate Reviewed-by: Paul Jackson <pj@sgi.com> Reviewed-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* cpufreq: Initialise default governor before useJohannes Weiner2008-01-171-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | When the cpufreq driver starts up at boot time, it calls into the default governor which might not be initialised yet. This hurts when the governor's worker function relies on memory that is not yet set up by its init function. This migrates all governors from module_init() to fs_initcall() when being the default, as was already done in cpufreq_performance when it was the only possible choice. The performance governor is always initialized early because it might be used as fallback even when not being the default. Fixes at least one actual oops where ondemand is the default governor and cpufreq_governor_dbs() uses the uninitialised kondemand_wq work-queue during boot-time. Signed-off-by: Johannes Weiner <hannes@saeurebad.de> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [CPUFREQ] Fix up whitespace in conservative governor.Dave Jones2007-10-221-61/+60
| | | | Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] Make cpufreq_conservative handle out-of-sync events properlyElias Oltmanns2007-10-221-2/+30
| | | | | | | | | | | | Make cpufreq_conservative handle out-of-sync events properly Currently, the cpufreq_conservative governor doesn't get notified when the actual frequency the cpu is running at differs from what cpufreq thought it was. As a result the cpu may stay at the maximum frequency after a s2ram / resume cycle even though the system is idle. Signed-off-by: Elias Oltmanns <eo@nebensachen.de> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] allow ondemand and conservative cpufreq governors to be used as ↵Thomas Renninger2007-10-041-10/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | default Depending on the transition latency of the HW for cpufreq switches, the ondemand or conservative governor cannot be used with certain cpufreq drivers. Still the ondemand should be the default governor on a wide range of systems. This patch allows this and lets the governor fallback to the performance governor at cpufreq driver load time, if the driver does not support fast enough frequency switching. Main benefit is that on e.g. installation or other systems without userspace support a working dynamic cpufreq support can be achieved on most systems by simply loading the cpufreq driver. This is especially essential for recent x86(_64) laptop hardware which may rely on working dynamic cpufreq OS support. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Bryan Wu <bryan.wu@analog.com> Cc: Andi Kleen <ak@suse.de> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dave Jones <davej@redhat.com>
* Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreqLinus Torvalds2007-02-161-2/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq: [CPUFREQ] Longhaul - Redo Longhaul ver. 2 [CPUFREQ] EPS - Correct 2nd brand test [CPUFREQ] Longhaul - Separate frequency and voltage transition [CPUFREQ] Longhaul - Models of Nehemiah [CPUFREQ] Whitespace fixup [CPUFREQ] Longhaul - Simplier minmult [CPUFREQ] CPU_FREQ_TABLE shouldn't be a def_tristate [CPUFREQ] ondemand governor use new cpufreq rwsem locking in work callback [CPUFREQ] ondemand governor restructure the work callback [CPUFREQ] Rewrite lock in cpufreq to eliminate cpufreq/hotplug related issues [CPUFREQ] Remove hotplug cpu crap [CPUFREQ] Enhanced PowerSaver driver [CPUFREQ] Longhaul - Add VT8235 support [CPUFREQ] Longhaul - Fix guess_fsb function [CPUFREQ] Longhaul - Remove duplicate tables [CPUFREQ] Longhaul - Introduce Nehemiah C [CPUFREQ] fix cpuinfo_cur_freq for CPU_HW_PSTATE [CPUFREQ] Longhaul - Remove "ignore_latency" option
| * [CPUFREQ] Remove hotplug cpu crapDave Jones2007-02-101-2/+0
| | | | | | | | | | | | | | | | | | The hotplug CPU locking in cpufreq is horrendous. No-one seems to care enough to fix it, so just remove it so that the 99.9% of the real world users of this code can use cpufreq without being bothered by warnings. Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dave Jones <davej@redhat.com>
* | [PATCH] remove many unneeded #includes of sched.hTim Schmielau2007-02-141-1/+0
|/ | | | | | | | | | | | | | | | | | | | | | | | After Al Viro (finally) succeeded in removing the sched.h #include in module.h recently, it makes sense again to remove other superfluous sched.h includes. There are quite a lot of files which include it but don't actually need anything defined in there. Presumably these includes were once needed for macros that used to live in sched.h, but moved to other header files in the course of cleaning it up. To ease the pain, this time I did not fiddle with any header files and only removed #includes from .c-files, which tend to cause less trouble. Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha, arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig, allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all configs in arch/arm/configs on arm. I also checked that no new warnings were introduced by the patch (actually, some warnings are removed that were emitted by unnecessarily included header files). Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge ../linusDave Jones2006-12-121-4/+3
|\ | | | | | | | | | | Conflicts: drivers/cpufreq/cpufreq.c
| * WorkStruct: make allyesconfigDavid Howells2006-11-221-4/+3
| | | | | | | | | | | | Fix up for make allyesconfig. Signed-Off-By: David Howells <dhowells@redhat.com>
* | [CPUFREQ] Fix coding style issues in cpufreq.Gautham R Shenoy2006-11-061-8/+15
| | | | | | | | | | | | | | | | Clean up cpufreq subsystem to fix coding style issues and to improve the readability. Signed-off-by: Gautham R Shenoy <ego@in.ibm.com> Signed-off-by: Dave Jones <davej@redhat.com>
* | [CPUFREQ] handle sysfs errorsJeff Garzik2006-10-211-1/+9
|/ | | | | | Signed-off-by: Jeff Garzik <jeff@garzik.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Dave Jones <davej@redhat.com>
* [PATCH] Reorganize the cpufreq cpu hotplug locking to not be totally bizareArjan van de Ven2006-07-261-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The patch below moves the cpu hotplugging higher up in the cpufreq layering; this is needed to avoid recursive taking of the cpu hotplug lock and to otherwise detangle the mess. The new rules are: 1. you must do lock_cpu_hotplug() around the following functions: __cpufreq_driver_target __cpufreq_governor (for CPUFREQ_GOV_LIMITS operation only) __cpufreq_set_policy 2. governer methods (.governer) must NOT take the lock_cpu_hotplug() lock in any way; they are called with the lock taken already 3. if your governer spawns a thread that does things, like calling __cpufreq_driver_target, your thread must honor rule #1. 4. the policy lock and other cpufreq internal locks nest within the lock_cpu_hotplug() lock. I'm not entirely happy about how the __cpufreq_governor rule ended up (conditional locking rule depending on the argument) but basically all callers pass this as a constant so it's not too horrible. The patch also removes the cpufreq_governor() function since during the locking audit it turned out to be entirely unused (so no need to fix it) The patch works on my testbox, but it could use more testing (otoh... it can't be much worse than the current code) Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] cpufreq build fixAndrew Morton2006-06-231-0/+1
| | | | | | | | | | | | | drivers/cpufreq/cpufreq_ondemand.c: In function 'do_dbs_timer': drivers/cpufreq/cpufreq_ondemand.c:374: warning: implicit declaration of function 'lock_cpu_hotplug' drivers/cpufreq/cpufreq_ondemand.c:381: warning: implicit declaration of function 'unlock_cpu_hotplug' drivers/cpufreq/cpufreq_conservative.c: In function 'do_dbs_timer': drivers/cpufreq/cpufreq_conservative.c:425: warning: implicit declaration of function 'lock_cpu_hotplug' drivers/cpufreq/cpufreq_conservative.c:432: warning: implicit declaration of function 'unlock_cpu_hotplug' Cc: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [CPUFREQ] Fix ondemand vs suspend deadlockVenkatesh Pallipadi2006-06-211-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rootcaused the bug to a deadlock in cpufreq and ondemand. Due to non-existent ordering between cpu_hotplug lock and dbs_mutex. Basically a race condition between cpu_down() and do_dbs_timer(). cpu_down() flow: * cpu_down() call for CPU 1 * Takes hot plug lock * Calls pre down notifier * cpufreq notifier handler calls cpufreq_driver_target() which takes cpu_hotplug lock again. OK as cpu_hotplug lock is recursive in same process context * CPU 1 goes down * Calls post down notifier * cpufreq notifier handler calls ondemand event stop which takes dbs_mutex So, cpu_hotplug lock is taken before dbs_mutex in this flow. do_dbs_timer is triggerred by a periodic timer event. It first takes dbs_mutex and then takes cpu_hotplug lock in cpufreq_driver_target(). Note the reverse order here compared to above. So, if this timer event happens at right moment during cpu_down, system will deadlok. Attached patch fixes the issue for both ondemand and conservative. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] Remove pointless check in conservative governor.Dave Jones2006-04-011-4/+2
| | | | | | < 0 checks on unsigned variables are pointless. Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] cpufreq_conservative: keep ignore_nice_load and freq_step values ↵Mattia Dongili2006-03-281-2/+2
| | | | | | | | | | when reselected Keep the value of ignore_nice_load and freq_step of the conservative governor after the governor is deselected and reselected. Signed-off-by: Mattia Dongili <malattia@linux.it> Signed-off-by: Dave Jones <davej@redhat.com>
* [PATCH] cpufreq_conservative: alternative initialise approachAlexander Clouter2006-03-261-37/+18
| | | | | | | | | | | | | Venki, author of cpufreq_ondemand, came up with a neater way to remove the initialiser code from the main loop of my code and out to the point when the governor is actually initialised. Not only does it look but it also feels cleaner, plus its simpler to understand. It also saves a bunch of pointless conditional statements in the main loop. Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
* [PATCH] cpufreq_conservative: make for_each_cpu() safeAlexander Clouter2006-03-261-49/+42
| | | | | | | | | | | | | | | | | | | All these changes should make cpufreq_conservative safe in regards to the x86 for_each_cpu cpumask.h changes and whatnot. Whilst making it safe a number of pointless for loops related to the cpu mask's were removed. I was never comfortable with all those for loops, especially as the iteration is over the same data again and again for each CPU you had in a single poll, an O(n^2) outcome to frequency scaling. The approach I use is to assume by default no CPU's exist and it sets the requested_freq to zero as a kind of flag, the reasoning is in the source ;) If the CPU is queried and requested_freq is zero then it initialises the variable to current_freq and then continues as if nothing happened which should be the same net effect as before? Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
* [PATCH] cpufreq_conservative: alter default responsivenessAlexander Clouter2006-03-261-1/+1
| | | | | | | | | | | The sensible approach to making conservative less responsive than ondemand :) As mentioned in patch [1/4]. We do not want conservative to shoot through all the frequencies, its point (by default) is to slowly move through them. By default its ten times less responsive. Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
* [PATCH] cpufreq_conservative: aligning of codebase with ondemandAlexander Clouter2006-03-261-26/+27
| | | | | | | | | | | | | | | | | | | | | | | | | Since the conservative govenor was released its codebase has drifted from the the direction and updates that have been applied to the ondemand govornor. This patch addresses the lack of updates in that period and brings conservative back up to date. The resulting diff file between cpufreq_ondemand.c and cpufreq_conservative.c is now much smaller and shows more clearly the differences between the two. Another reason to do this is ages ago, knowingly, I did a piss poor attempt at making conservative less responsive by knocking up DEF_SAMPLING_RATE_LATENCY_MULTIPLIER by two orders of magnitude. I did fix this ages ago but in my dis-organisation I must have toasted the diff and left it the way it was. About two weeks ago a user contacted me saying he was having problems with the conservative governor with his AMD Athlon XP-M 2800+ as /sys/devices/system/cpu/cpu0/cpufreq/conservative showed sampling_rate_min 9950000 sampling_rate_max 1360065408 Nine seconds to decide about changing the frequency....not too responsive :) Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
* [CPUFREQ] Convert drivers/cpufreq semaphores to mutexes.akpm@osdl.org2006-01-181-26/+26
| | | | | | | | | | | | Semaphore to mutex conversion. The conversion was generated via scripts, and the result was validated automatically via a script as well. Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Dave Jones <davej@redhat.com>
* [PATCH] cpufreq_conservative/ondemand: invert meaning of 'ignore nice'Alexander Clouter2005-12-011-5/+5
| | | | | | | | | | | | | | | | | | The use of the 'ignore_nice' sysfs file is confusing to anyone using it. This removes the sysfs file 'ignore_nice' and in its place creates a 'ignore_nice_load' entry that defaults to '0'; meaning nice'd processes _are_ counted towards the 'business' calculation. WARNING: this obvious breaks any userland tools that expected ignore_nice' to exist, to draw attention to this fact it was concluded on the mailing list that the entry should be removed altogether so the userland app breaks and so the author can build simple to detect workaround. Having said that it seems currently very few tools even make use of this functionality; all I could find was a Gentoo Wiki entry. Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Dave Jones <davej@redhat.com>
* [PATCH] cpufreq: SMP fix for conservative governorDave Jones2005-10-271-3/+3
| | | | | | | | | | | | Don't try to access not-present CPUs. Conservative governor will always oops on SMP without this fix. Fixes http://bugzilla.kernel.org/show_bug.cgi?id=4781 Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [CPUFREQ] ondemand,conservative governor idle_tick clean-upDave Jones2005-05-311-21/+5
| | | | | | | | | | | | [PATCH] [3/5] ondemand,conservative governor idle_tick clean-up Ondemand and conservative governor clean-up, it factorises the idle ticks measurement. Signed-off-by: Eric Piel <eric.piel@tremplin-utc.net> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
* [CPUFREQ] ondemand,conservative governor store the idle ticks for all cpusDave Jones2005-05-311-1/+7
| | | | | | | | | | | | [PATCH] [2/5] ondemand,conservative governor store the idle ticks for all cpus Ondemand, conservative governor did not store prev_cpu_idle_up into prev_cpu_idle_down for other CPUs than the current CPU. Signed-off-by: Eric Piel <eric.piel@tremplin-utc.net> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
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