summaryrefslogtreecommitdiff
path: root/drivers/cpufreq/cpufreq.c
AgeCommit message (Collapse)Author
2012-07-13cpufreq: Protected access of policy attributePuneet Saxena
It takes read RW semaphore to access policy governor bug 997731 Change-Id: Ibdc3dd54cf6076c0fef4bc58f144e4bcb4631d76 Signed-off-by: Puneet Saxena <puneets@nvidia.com> Reviewed-on: http://git-master/r/107079 GVS: Gerrit_Virtual_Submit Reviewed-by: Sang-Hun Lee <sanlee@nvidia.com> Reviewed-by: Peter Boonstoppel <pboonstoppel@nvidia.com> Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
2012-05-17cpufreq: Don't clip PM QoS requests to old policy limitsAlex Frid
Clipping PM QoS requests to combined old policy limits that include both PM QoS and user policy requests creates a circular dependency. As a result new PM QoS maximum limit is rejected if it is above previous PM QoS minimum limit even though the new PM QoS minimum limit has been already lowered below new PM QoS maximum limit. Instead clip PM QoS request to the old user policy limits only. Change-Id: Ice0a53a699e0798f07f0e32d6b8a28586fe5db0c Signed-off-by: Alex Frid <afrid@nvidia.com> Reviewed-on: http://git-master/r/102386 Reviewed-by: Automatic_Commit_Validation_User Reviewed-by: Donghan Ryu <dryu@nvidia.com> Reviewed-by: Antti Miettinen <amiettinen@nvidia.com> Reviewed-by: Diwakar Tundlam <dtundlam@nvidia.com> Tested-by: Vikas Ramesh Kedigehalli <vikasr@nvidia.com>
2012-05-08cpufreq: interface for setting governor for a cpuPuneet Saxena
This implementation sets governor for a cpu using existing cpufreq interfaces. bug 871958 Change-Id: Ic4e7e2a2b0babaf1829b559b5db211666d449b86 Signed-off-by: Puneet Saxena <puneets@nvidia.com> Reviewed-on: http://git-master/r/97939 Reviewed-by: Automatic_Commit_Validation_User Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
2012-04-12tracing: Add tracepoints for CPU scalingAntti P Miettinen
Simple tracepoints for measuring CPU scaling latencies. Bug 960307 Change-Id: I6fd4e67e352a2ff134da58866d943457506d080b Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com> Reviewed-on: http://git-master/r/93080 Reviewed-by: Automatic_Commit_Validation_User Reviewed-by: Juha Tukkinen <jtukkinen@nvidia.com>
2012-03-21cpufreq: Typecast compared integersAntti P Miettinen
The min/max frequencies in cpufreq_policy are unsigned integers but pm_qos_request() returns a signed int. Compare as unsigned, frequencies are never negative. Bug 949219 Change-Id: Iba0de9ad6bf221f7a2e5560f597aa56cbeb7b6f6 Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com> Reviewed-on: http://git-master/r/91214 Reviewed-by: Automatic_Commit_Validation_User Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com> Reviewed-by: Juha Tukkinen <jtukkinen@nvidia.com>
2012-02-09cpufreq: properly clamp QoS min/maxDonghan Ryu
typically PM QoS clients request the maximum cpu frequency by setting cpu_freq_min to INT_MAX. Therefore, we need to clamp INT_MAX to whatever the maximum frequency allowed by the policy to make the requested cpu_freq_min is same as the maximum allowed cpu frequency. Inverse logic applies to the cpu_freq_max as well. Bug 932477 Signed-off-by: Donghan Ryu <dryu@nvidia.com> Reviewed-on: http://git-master/r/78401 (cherry picked from commit 9688430a621515f3afe3e0ab358ea7ad5aab6d91) Change-Id: Ie5edcd4a873ed5cce45ec0f9b981f28db6091ff1 Signed-off-by: Pritesh Raithatha <praithatha@nvidia.com> Reviewed-on: http://git-master/r/80002 Reviewed-by: Automatic_Commit_Validation_User Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
2012-01-19cpufreq: Preserve sysfs min/max requestAntti P Miettinen
Store the value received via sysfs as the user_policy min/max value instead of the currently enforced min/max. This allows restoring the user min/max values when constraints on enforced min/max change. Bug 888312 Change-Id: I8a5adf022585e5bd91fa3b1d8d448065efa6827a Reviewed-on: http://git-master/r/73982 Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com> Signed-off-by: Varun Wadekar <vwadekar@nvidia.com> Reviewed-on: http://git-master/r/75886 Reviewed-by: Automatic_Commit_Validation_User
2012-01-19cpufreq: Enforce PM QoS min/max limitsAntti P Miettinen
Observe PM QoS CPU frequency minimum and maximum in addition to policy settings. Bug 888312 Change-Id: Ia4f60a1649a9952e02f6847c8add3b2ea5d47524 Reviewed-on: http://git-master/r/72207 Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com> Signed-off-by: Varun Wadekar <vwadekar@nvidia.com> Reviewed-on: http://git-master/r/75884 Reviewed-by: Automatic_Commit_Validation_User
2012-01-19cpufreq: Export user_policy min/maxAntti P Miettinen
Add sysfs nodes for user_policy min and max settings. Bug 888312 Change-Id: Ife8ec07f8faebc0c04e7ecf6e24976a311bad73b Reviewed-on: http://git-master/r/72201 Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com> Signed-off-by: Varun Wadekar <vwadekar@nvidia.com> Reviewed-on: http://git-master/r/75882 Reviewed-by: Automatic_Commit_Validation_User
2011-06-28cpufreq: expose a cpufreq_quick_get_max routineJesse Barnes
This allows drivers and other code to get the max reported CPU frequency. Initial use is for scaling ring frequency with GPU frequency in the i915 driver. Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Keith Packard <keithp@keithp.com>
2011-05-04[CPUFREQ] remove redundant sprintf from request_module call.Kees Cook
Since format string handling is part of request_module, there is no need to construct the module name. As such, drop the redundant sprintf and heap usage. Signed-off-by: Kees Cook <kees.cook@canonical.com> Signed-off-by: Dave Jones <davej@redhat.com>
2011-05-04[CPUFREQ] use dynamic debug instead of custom infrastructureDominik Brodowski
With dynamic debug having gained the capability to report debug messages also during the boot process, it offers a far superior interface for debug messages than the custom cpufreq infrastructure. As a first step, remove the old cpufreq_debug_printk() function and replace it with a call to the generic pr_debug() function. How can dynamic debug be used on cpufreq? You need a kernel which has CONFIG_DYNAMIC_DEBUG enabled. To enabled debugging during runtime, mount debugfs and $ echo -n 'module cpufreq +p' > /sys/kernel/debug/dynamic_debug/control for debugging the complete "cpufreq" module. To achieve the same goal during boot, append ddebug_query="module cpufreq +p" as a boot parameter to the kernel of your choice. For more detailled instructions, please see Documentation/dynamic-debug-howto.txt Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Dave Jones <davej@redhat.com>
2011-05-04[CPUFREQ] CPU hotplug, re-create sysfs directory and symlinksJacob Shin
When we discover CPUs that are affected by each other's frequency/voltage transitions, the first CPU gets a sysfs directory created, and rest of the siblings get symlinks. Currently, when we hotplug off only the first CPU, all of the symlinks and the sysfs directory gets removed. Even though rest of the siblings are still online and functional, they are orphaned, and no longer governed by cpufreq. This patch, given the above scenario, creates a sysfs directory for the first sibling and symlinks for the rest of the siblings. Please note the recursive call, it was rather too ugly to roll it out. And the removal of redundant NULL setting (it is already taken care of near the top of the function). Signed-off-by: Jacob Shin <jacob.shin@amd.com> Acked-by: Mark Langsdorf <mark.langsdorf@amd.com> Reviewed-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com> Cc: stable@kernel.org
2011-03-31Fix common misspellingsLucas De Marchi
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-23cpufreq: Use syscore_ops for boot CPU suspend/resume (v2)Rafael J. Wysocki
The cpufreq subsystem uses sysdev suspend and resume for executing cpufreq_suspend() and cpufreq_resume(), respectively, during system suspend, after interrupts have been switched off on the boot CPU, and during system resume, while interrupts are still off on the boot CPU. In both cases the other CPUs are off-line at the relevant point (either they have been switched off via CPU hotplug during suspend, or they haven't been switched on yet during resume). For this reason, although it may seem that cpufreq_suspend() and cpufreq_resume() are executed for all CPUs in the system, they are only called for the boot CPU in fact, which is quite confusing. To remove the confusion and to prepare for elimiating sysdev suspend and resume operations from the kernel enirely, convernt cpufreq to using a struct syscore_ops object for the boot CPU suspend and resume and rename the callbacks so that their names reflect their purpose. In addition, put some explanatory remarks into their kerneldoc comments. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-03-16[CPUFREQ] Remove the pm_message_t argument from driver suspendRafael J. Wysocki
None of the existing cpufreq drivers uses the second argument of its .suspend() callback (which isn't useful anyway), so remove it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Dave Jones <davej@redhat.com>
2011-03-01[CPUFREQ] fix BUG on cpufreq policy init failureJiri Slaby
cpufreq_register_driver sets cpufreq_driver to a structure owned (and placed) in the caller's memory. If cpufreq policy fails in its ->init function, sysdev_driver_register returns nonzero in cpufreq_register_driver. Now, cpufreq_register_driver returns an error without setting cpufreq_driver back to NULL. Usually cpufreq policy modules are unloaded because they propagate the error to the module init function and return that. So a later access to any member of cpufreq_driver causes bugs like: BUG: unable to handle kernel paging request at ffffffffa00270a0 IP: [<ffffffff8145eca3>] cpufreq_cpu_get+0x53/0xe0 PGD 1805067 PUD 1809063 PMD 1c3f90067 PTE 0 Oops: 0000 [#1] SMP last sysfs file: /sys/devices/virtual/net/tun0/statistics/collisions CPU 0 Modules linked in: ... Pid: 5677, comm: thunderbird-bin Tainted: G W 2.6.38-rc4-mm1_64+ #1389 To be filled by O.E.M./To Be Filled By O.E.M. RIP: 0010:[<ffffffff8145eca3>] [<ffffffff8145eca3>] cpufreq_cpu_get+0x53/0xe0 RSP: 0018:ffff8801aec37d98 EFLAGS: 00010086 RAX: 0000000000000202 RBX: 0000000000000000 RCX: 0000000000000001 RDX: ffffffffa00270a0 RSI: 0000000000001000 RDI: ffffffff8199ece8 ... Call Trace: [<ffffffff8145f490>] cpufreq_quick_get+0x10/0x30 [<ffffffff8103f12b>] show_cpuinfo+0x2ab/0x300 [<ffffffff81136292>] seq_read+0xf2/0x3f0 [<ffffffff8126c5d3>] ? __strncpy_from_user+0x33/0x60 [<ffffffff8116850d>] proc_reg_read+0x6d/0xa0 [<ffffffff81116e53>] vfs_read+0xc3/0x180 [<ffffffff81116f5c>] sys_read+0x4c/0x90 [<ffffffff81030dbb>] system_call_fastpath+0x16/0x1b ... It's all cause by weird fail path handling in cpufreq_register_driver. To fix that, shuffle the code to do proper handling with gotos. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Dave Jones <davej@redhat.com>
2011-01-04perf: Clean up power events by introducing new, more generic onesThomas Renninger
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>
2010-10-22[CPUFREQ] drivers/cpufreq: Adjust confusing if indentationJulia Lawall
Indent the body of for_each_cpu. The semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @r disable braces4@ position p1,p2; statement S1,S2; @@ ( if (...) { ... } | if (...) S1@p1 S2@p2 ) @script:python@ p1 << r.p1; p2 << r.p2; @@ if (p1[0].column == p2[0].column): cocci.print_main("branch",p1) cocci.print_secs("after",p2) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Dave Jones <davej@redhat.com>
2010-08-03[CPUFREQ] fix brace coding style issue.Neal Buckendahl
This patch fixes up a brace warning found by the checkpatch.pl tool Signed-off-by: Neal Buckendahl <nealb001@tbcnet.com> Signed-off-by: Dave Jones <davej@redhat.com>
2010-08-03[CPUFREQ] x86 cpufreq: Make trace_power_frequency cpufreq driver independentThomas Renninger
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>
2010-08-03[CPUFREQ] unexport (un)lock_policy_rwsem* functionsAmerigo Wang
lock_policy_rwsem_* and unlock_policy_rwsem_* functions are scheduled to be unexported when 2.6.33. Now there are no other callers of them out of cpufreq.c, unexport them and make them static. Signed-off-by: WANG Cong <amwang@redhat.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
2010-08-03[CPUFREQ] fix memory leak in cpufreq_add_devXiaotian Feng
We didn't free policy->related_cpus in error path err_unlock_policy. This is catched by following kmemleak report: unreferenced object 0xffff88022a0b96d0 (size 512): comm "modprobe", pid 886, jiffies 4294689177 (age 780.694s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff8111ebe5>] create_object+0x186/0x281 [<ffffffff814fad4f>] kmemleak_alloc+0x60/0xa7 [<ffffffff8111127a>] kmem_cache_alloc_node_notrace+0x120/0x142 [<ffffffff81262e4f>] alloc_cpumask_var_node+0x2c/0xd7 [<ffffffff81262f0b>] alloc_cpumask_var+0x11/0x13 [<ffffffff81262f1c>] zalloc_cpumask_var+0xf/0x11 [<ffffffff8140fac0>] cpufreq_add_dev+0x11f/0x547 [<ffffffff81334bda>] sysdev_driver_register+0xc2/0x11d [<ffffffff8140e334>] cpufreq_register_driver+0xcb/0x1b8 [<ffffffffa032e040>] 0xffffffffa032e040 [<ffffffff810021ba>] do_one_initcall+0x5e/0x15c [<ffffffff81087f94>] sys_init_module+0xa6/0x1e6 [<ffffffff81009bc2>] system_call_fastpath+0x16/0x1b [<ffffffffffffffff>] 0xffffffffffffffff Signed-off-by: Xiaotian Feng <dfeng@redhat.com> Cc: Thomas Renninger <trenn@suse.de> Cc: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Dave Jones <davej@redhat.com>
2010-08-03[CPUFREQ] revert "[CPUFREQ] remove rwsem lock from CPUFREQ_GOV_STOP call ↵Andrej Gelenberg
(second call site)" 395913d0b1db37092ea3d9d69b832183b1dd84c5 ("[CPUFREQ] remove rwsem lock from CPUFREQ_GOV_STOP call (second call site)") is not needed, because there is no rwsem lock in cpufreq_ondemand and cpufreq_conservative anymore. Lock should not be released until the work done. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=1594 Signed-off-by: Andrej Gelenberg <andrej.gelenberg@udo.edu> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Dave Jones <davej@redhat.com>
2010-05-08Merge commit 'v2.6.34-rc6' into x86/cpuH. Peter Anvin
2010-04-09cpufreq: Unify sysfs attribute definition macrosBorislav Petkov
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>
2010-03-31[CPUFREQ] fix a lockdep warningAmerigo Wang
There is no need to do sysfs_remove_link() or kobject_put() etc. when policy_rwsem_write is held, move them after releasing the lock. This fixes the lockdep warning: halt/4071 is trying to acquire lock: (s_active){++++.+}, at: [<c0000000001ef868>] .sysfs_addrm_finish+0x58/0xc0 but task is already holding lock: (&per_cpu(cpu_policy_rwsem, cpu)){+.+.+.}, at: [<c0000000004cd6ac>] .lock_policy_rwsem_write+0x84/0xf4 Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: WANG Cong <amwang@redhat.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
2010-03-07Driver core: Constify struct sysfs_ops in struct kobj_typeEmese Revfy
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>
2009-12-14Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits) m68k: rename global variable vmalloc_end to m68k_vmalloc_end percpu: add missing per_cpu_ptr_to_phys() definition for UP percpu: Fix kdump failure if booted with percpu_alloc=page percpu: make misc percpu symbols unique percpu: make percpu symbols in ia64 unique percpu: make percpu symbols in powerpc unique percpu: make percpu symbols in x86 unique percpu: make percpu symbols in xen unique percpu: make percpu symbols in cpufreq unique percpu: make percpu symbols in oprofile unique percpu: make percpu symbols in tracer unique percpu: make percpu symbols under kernel/ and mm/ unique percpu: remove some sparse warnings percpu: make alloc_percpu() handle array types vmalloc: fix use of non-existent percpu variable in put_cpu_var() this_cpu: Use this_cpu_xx in trace_functions_graph.c this_cpu: Use this_cpu_xx for ftrace this_cpu: Use this_cpu_xx in nmi handling this_cpu: Use this_cpu operations in RCU this_cpu: Use this_cpu ops for VM statistics ... Fix up trivial (famous last words) global per-cpu naming conflicts in arch/x86/kvm/svm.c mm/slab.c
2009-11-24[ACPI/CPUFREQ] Introduce bios_limit per cpu cpufreq sysfs interfaceThomas Renninger
This interface is mainly intended (and implemented) for ACPI _PPC BIOS frequency limitations, but other cpufreq drivers can also use it for similar use-cases. Why is this needed: Currently it's not obvious why cpufreq got limited. People see cpufreq/scaling_max_freq reduced, but this could have happened by: - any userspace prog writing to scaling_max_freq - thermal limitations - hardware (_PPC in ACPI case) limitiations Therefore export bios_limit (in kHz) to: - Point the user that it's the BIOS (broken or intended) which limits frequency - Export it as a sysfs interface for userspace progs. While this was a rarely used feature on laptops, there will appear more and more server implemenations providing "Green IT" features like allowing the service processor to limit the frequency. People want to know about HW/BIOS frequency limitations. All ACPI P-state driven cpufreq drivers are covered with this patch: - powernow-k8 - powernow-k7 - acpi-cpufreq Tested with a patched DSDT which limits the first two cores (_PPC returns 1) via _PPC, exposed by bios_limit: # echo 2200000 >cpu2/cpufreq/scaling_max_freq # cat cpu*/cpufreq/scaling_max_freq 2600000 2600000 2200000 2200000 # #scaling_max_freq shows general user/thermal/BIOS limitations # cat cpu*/cpufreq/bios_limit 2600000 2600000 2800000 2800000 # #bios_limit only shows the HW/BIOS limitation CC: Pallipadi Venkatesh <venkatesh.pallipadi@intel.com> CC: Len Brown <lenb@kernel.org> CC: davej@codemonkey.org.uk CC: linux@dominikbrodowski.net Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
2009-11-24[CPUFREQ] make internal cpufreq_add_dev_* staticAlex Chiang
No need to export these symbols; make them static. cpufreq_add_dev_policy cpufreq_add_dev_symlink cpufreq_add_dev_interface Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Dave Jones <davej@redhat.com>
2009-11-17[CPUFREQ] Fix stale cpufreq_cpu_governor pointerPrarit Bhargava
Dave, Attached is an update of my patch against the cpufreq fixes branch. Before applying the patch I compiled and booted the tree to see if the panic was still there -- to my surprise it was not. This is because of the conversion of cpufreq_cpu_governor to a char[]. While the panic is kaput, the problem of stale data continues and my patch is still valid. It is possible to end up with the wrong governor after hotplug events because CPUFREQ_DEFAULT_GOVERNOR is statically linked to a default, while the cpu siblings may have had a different governor assigned by a user. ie) the patch is still needed in order to keep the governors assigned properly when hotplugging devices Signed-off-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Dave Jones <davej@redhat.com>
2009-11-17[CPUFREQ] Fix use after free on governor restoreDmitry Monakhov
Currently on governer backup/restore path we storing governor's pointer. This is wrong because one may unload governor's module after cpu goes offline. As result use-after-free will take place on restored cpu. It is not easy to exploit this bug, but still we have to close this issue ASAP. Issue was introduced by following commit 084f34939424161669467c19280dbcf637730314 ##TESTCASE## #!/bin/sh -x modprobe acpi_cpufreq # Any non default governor, in may case it is "ondemand" modprobe cpufreq_ondemand echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor rmmod acpi_cpufreq rmmod cpufreq_ondemand modprobe acpi_cpufreq # << use-after-free here. Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Dave Jones <davej@redhat.com>
2009-10-29percpu: make percpu symbols in cpufreq uniqueTejun Heo
This patch updates percpu related symbols in cpufreq such that percpu symbols are unique and don't clash with local symbols. This serves two purposes of decreasing the possibility of global percpu symbol collision and allowing dropping per_cpu__ prefix from percpu symbols. * drivers/cpufreq/cpufreq.c: s/policy_cpu/cpufreq_policy_cpu/ * drivers/cpufreq/freq_table.c: s/show_table/cpufreq_show_table/ * arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c: s/drv_data/acfreq_data/ s/old_perf/acfreq_old_perf/ Partly based on Rusty Russell's "alloc_percpu: rename percpu vars which cause name clashes" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au>
2009-09-01[CPUFREQ] remove rwsem lock from CPUFREQ_GOV_STOP call (second call site)Mathieu Desnoyers
remove rwsem lock from CPUFREQ_GOV_STOP call (second call site) commit 42a06f2166f2f6f7bf04f32b4e823eacdceafdc9 Missed a call site for CPUFREQ_GOV_STOP to remove the rwlock taken around the teardown. To make a long story short, the rwlock write-lock causes a circular dependency with cancel_delayed_work_sync(), because the timer handler takes the read lock. Note that all callers to __cpufreq_set_policy are taking the rwsem. All sysfs callers (writers) hold the write rwsem at the earliest sysfs calling stage. However, the rwlock write-lock is not needed upon governor stop. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> CC: rjw@sisk.pl CC: mingo@elte.hu CC: Shaohua Li <shaohua.li@intel.com> CC: Pekka Enberg <penberg@cs.helsinki.fi> CC: Dave Young <hidave.darkstar@gmail.com> CC: "Rafael J. Wysocki" <rjw@sisk.pl> CC: Rusty Russell <rusty@rustcorp.com.au> CC: trenn@suse.de CC: sven.wegener@stealer.net CC: cpufreq@vger.kernel.org Signed-off-by: Dave Jones <davej@redhat.com>
2009-09-01[CPUFREQ] Introduce global, not per core: /sys/devices/system/cpu/cpufreqThomas Renninger
Currently everything in the cpufreq layer is per core based. This does not reflect reality, for example ondemand on conservative governors have global sysfs variables. Introduce a global cpufreq directory and add the kobject to the governor struct, so that governors can easily access it. The directory is initialized in the cpufreq_core_init initcall and thus will always be created if cpufreq is compiled in, even if no cpufreq driver is active later. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
2009-09-01[CPUFREQ] Bail out of cpufreq_add_dev if the link for a managed CPU got createdThomas Renninger
Doing: echo 0 >cpu1/online echo 1 >cpu1/online on a managed CPU will result in: Jul 22 15:15:37 linux kernel: [ 80.013864] WARNING: at fs/sysfs/dir.c:487 sysfs_add_one+0xcf/0xe6() Jul 22 15:15:37 linux kernel: [ 80.013866] Hardware name: To Be Filled By O.E.M. Jul 22 15:15:37 linux kernel: [ 80.013868] sysfs: cannot create duplicate filename '/devices/system/cpu/cpu1/cpufreq' Jul 22 15:15:37 linux kernel: [ 80.013870] Modules linked in: powernow_k8 Jul 22 15:15:37 linux kernel: [ 80.013874] Pid: 5750, comm: bash Not tainted 2.6.31-rc2 #40 Jul 22 15:15:37 linux kernel: [ 80.013876] Call Trace: Jul 22 15:15:37 linux kernel: [ 80.013879] [<ffffffff8112ebda>] ? sysfs_add_one+0xcf/0xe6 Jul 22 15:15:37 linux kernel: [ 80.013884] [<ffffffff81041926>] warn_slowpath_common+0x77/0xa4 Jul 22 15:15:37 linux kernel: [ 80.013888] [<ffffffff810419a0>] warn_slowpath_fmt+0x3c/0x3e Jul 22 15:15:37 linux kernel: [ 80.013891] [<ffffffff8112ebda>] sysfs_add_one+0xcf/0xe6 Jul 22 15:15:37 linux kernel: [ 80.013894] [<ffffffff8112f213>] create_dir+0x58/0x87 Jul 22 15:15:37 linux kernel: [ 80.013898] [<ffffffff8112f27a>] sysfs_create_dir+0x38/0x4f Jul 22 15:15:37 linux kernel: [ 80.013902] [<ffffffff811ffb8a>] kobject_add_internal+0x11f/0x1de Jul 22 15:15:37 linux kernel: [ 80.013905] [<ffffffff811ffd21>] kobject_add_varg+0x41/0x4e Jul 22 15:15:37 linux kernel: [ 80.013908] [<ffffffff811ffd7a>] kobject_init_and_add+0x4c/0x57 Jul 22 15:15:37 linux kernel: [ 80.013913] [<ffffffff810667bc>] ? mark_lock+0x22/0x228 Jul 22 15:15:37 linux kernel: [ 80.013918] [<ffffffff813e8a3b>] cpufreq_add_dev_interface+0x40/0x1e4 ... This bug slipped in by git commit: 150b06f7f223cfd0f808737a5243cceca8ea47fa When splitting up cpufreq_add_dev, the whole cpufreq_add_dev function is not left anymore, only cpufreq_add_dev_policy. This patch should reconstruct the identical functionality again as it was before the split. CC: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
2009-09-01[CPUFREQ] Factor out policy setting from cpufreq_add_devDave Jones
Signed-off-by: Dave Jones <davej@redhat.com>
2009-09-01[CPUFREQ] Factor out interface creation from cpufreq_add_devDave Jones
Signed-off-by: Dave Jones <davej@redhat.com>
2009-09-01[CPUFREQ] Factor out symlink creation from cpufreq_add_devDave Jones
Signed-off-by: Dave Jones <davej@redhat.com>
2009-09-01[CPUFREQ] cleanup up -ENOMEM handling in cpufreq_add_devDave Jones
Signed-off-by: Dave Jones <davej@redhat.com>
2009-09-01[CPUFREQ] Reduce scope of cpu_sys_dev in cpufreq_add_devDave Jones
Signed-off-by: Dave Jones <davej@redhat.com>
2009-09-01[CPUFREQ] Re-enable cpufreq suspend and resume codeDominik Brodowski
Commit 4bc5d3413503 is broken and causes regressions: (1) cpufreq_driver->resume() and ->suspend() were only called on __powerpc__, but you could set them on all architectures. In fact, ->resume() was defined and used before the PPC-related commit 42d4dc3f4e1e complained about in 4bc5d3413503. (2) Therfore, the resume functions in acpi_cpufreq and speedstep-smi would never be called. (3) This means speedstep-smi would be unusuable after suspend or resume. The _real_ problem was calling cpufreq_driver->get() with interrupts off, but it re-enabling interrupts on some platforms. Why is ->get() necessary? Some systems like to change the CPU frequency behind our back, especially during BIOS-intensive operations like suspend or resume. If such systems also use a CPU frequency-dependant timing loop, delays might be off by large factors. Therefore, we need to ascertain as soon as possible that the CPU frequency is indeed at the speed we think it is. You can do this two ways: either setting it anew, or trying to get it. The latter is what was done, the former also has the same IRQ issue. So, let's try something different: defer the checking to after interrupts are re-enabled, by calling cpufreq_update_policy() (via schedule_work()). Timings may be off until this later stage, so let's watch out for resume regressions caused by the deferred handling of frequency changes behind the kernel's back. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Dave Jones <davej@redhat.com>
2009-08-04[CPUFREQ] Make cpufreq suspend code conditional on powerpc.Dave Jones
The suspend code runs with interrupts disabled, and the powerpc workaround we do in the cpufreq suspend hook calls the drivers ->get method. powernow-k8's ->get does an smp_call_function_single which needs interrupts enabled cpufreq's suspend/resume code was added in 42d4dc3f4e1e to work around a hardware problem on ppc powerbooks. If we make all this code conditional on powerpc, we avoid the issue above. Signed-off-by: Dave Jones <davej@redhat.com>
2009-08-04[CPUFREQ] Fix a kobject reference bug related to managed CPUsThomas Renninger
The first offline/online cycle is successful, the second not. Doing: echo 0 >cpu1/online echo 1 >cpu1/online echo 0 >cpu1/online The last command will trigger: Jul 22 14:39:50 linux kernel: [ 593.210125] ------------[ cut here ]------------ Jul 22 14:39:50 linux kernel: [ 593.210139] WARNING: at lib/kref.c:43 kref_get+0x23/0x2b() Jul 22 14:39:50 linux kernel: [ 593.210144] Hardware name: To Be Filled By O.E.M. Jul 22 14:39:50 linux kernel: [ 593.210148] Modules linked in: powernow_k8 Jul 22 14:39:50 linux kernel: [ 593.210158] Pid: 378, comm: kondemand/2 Tainted: G W 2.6.31-rc2 #38 Jul 22 14:39:50 linux kernel: [ 593.210163] Call Trace: Jul 22 14:39:50 linux kernel: [ 593.210171] [<ffffffff812008e8>] ? kref_get+0x23/0x2b Jul 22 14:39:50 linux kernel: [ 593.210181] [<ffffffff81041926>] warn_slowpath_common+0x77/0xa4 Jul 22 14:39:50 linux kernel: [ 593.210190] [<ffffffff81041962>] warn_slowpath_null+0xf/0x11 Jul 22 14:39:50 linux kernel: [ 593.210198] [<ffffffff812008e8>] kref_get+0x23/0x2b Jul 22 14:39:50 linux kernel: [ 593.210206] [<ffffffff811ffa19>] kobject_get+0x1a/0x22 Jul 22 14:39:50 linux kernel: [ 593.210214] [<ffffffff813e815d>] cpufreq_cpu_get+0x8a/0xcb Jul 22 14:39:50 linux kernel: [ 593.210222] [<ffffffff813e87d1>] __cpufreq_driver_getavg+0x1d/0x67 Jul 22 14:39:50 linux kernel: [ 593.210231] [<ffffffff813ea18f>] do_dbs_timer+0x158/0x27f Jul 22 14:39:50 linux kernel: [ 593.210240] [<ffffffff810529ea>] worker_thread+0x200/0x313 ... The output continues on every do_dbs_timer ondemand freq checking poll. This regression was introduced by git commit: 3f4a782b5ce2698b1870b5a7b573cd721d4fce33 The policy is released when the cpufreq device is removed in: __cpufreq_remove_dev(): /* if this isn't the CPU which is the parent of the kobj, we * only need to unlink, put and exit */ Not creating the symlink is not sever at all. As long as: sysfs_remove_link(&sys_dev->kobj, "cpufreq"); handles it gracefully that the symlink did not exist. Possibly no error should be returned at all, because ondemand governor would still provide the same functionality. Userspace in userspace gov case might be confused if the link is missing. Resolves http://bugzilla.kernel.org/show_bug.cgi?id=13903 CC: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> CC: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
2009-08-04[CPUFREQ] Do not set policy for offline cpusPrarit Bhargava
Suspend/Resume fails on multi socket, multi core systems because the cpufreq code erroneously sets the per_cpu policy_cpu value when a logical cpu is offline. This most notably results in missing sysfs files that are used to set the cpu frequencies of the various cpus. Signed-off-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Dave Jones <davej@redhat.com>
2009-07-08[CPUFREQ] Fix compile failure in cpufreq.cDave Jones
managed_policy is out of scope for the non-smp case. Declare it locally where used (twice) Signed-off-by: Dave Jones <davej@redhat.com>
2009-07-06[CPUFREQ] fix (utter) cpufreq_add_dev messMathieu Desnoyers
OK, I've tried to clean it up the best I could, but please test this with concurrent cpu hotplug and cpufreq add/remove in loops. I'm sure we will make other interesting findings. This is step one of fixing the overall locking dependency mess in cpufreq. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> CC: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> CC: rjw@sisk.pl CC: mingo@elte.hu CC: Shaohua Li <shaohua.li@intel.com> CC: Pekka Enberg <penberg@cs.helsinki.fi> CC: Dave Young <hidave.darkstar@gmail.com> CC: "Rafael J. Wysocki" <rjw@sisk.pl> CC: Rusty Russell <rusty@rustcorp.com.au> CC: sven.wegener@stealer.net CC: cpufreq@vger.kernel.org CC: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
2009-07-06[CPUFREQ] Eliminate the recent lockdep warnings in cpufreqvenkatesh.pallipadi@intel.com
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>
2009-06-09cpumask: alloc zeroed cpumask for static cpumask_var_tsYinghai Lu
These are defined as static cpumask_var_t so if MAXSMP is not used, they are cleared already. Avoid surprises when MAXSMP is enabled. Signed-off-by: Yinghai Lu <yinghai.lu@kernel.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
generated by cgit v1.2.3 (git 2.0.4) at 2024-05-26 14:51:45 +0000