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2014-08-26cpufreq: Clean up header files included in the coreViresh Kumar
This patch addresses the following issues in the header files in the cpufreq core: - Include headers in ascending order, so that we don't add same many times by mistake. - <asm/> must be included after <linux/>, so that they override whatever they need to. - Remove unnecessary includes. - Don't include files already included by cpufreq.h or cpufreq_governor.h. Bug 1359622 [rjw: Changelog] Change-Id: I3d69d7243b982cd2e32abfdfb9dd750843a07629 Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> (cherry picked from commit 5ff0a268037d344f86df690ccb994d8bc015d2d9) Reviewed-on: http://git-master/r/482370 Tested-by: Rajkumar Kasirajan <rkasirajan@nvidia.com> GVS: Gerrit_Virtual_Submit Reviewed-by: Bibek Basu <bbasu@nvidia.com> Reviewed-by: Winnie Hsu <whsu@nvidia.com>
2014-06-05Merge branch 'linux-3.10.40' into rel-21Ishan Mittal
Bug 200004122 Conflicts: drivers/cpufreq/cpufreq.c drivers/regulator/core.c sound/soc/codecs/max98090.c Change-Id: I9418a05ad5c56b2e902249218bac2fa594d99f56 Signed-off-by: Ishan Mittal <imittal@nvidia.com>
2014-04-14cpufreq: Fix governor start/stop race conditionXiaoguang Chen
commit 95731ebb114c5f0c028459388560fc2a72fe5049 upstream. Cpufreq governors' stop and start operations should be carried out in sequence. Otherwise, there will be unexpected behavior, like in the example below. Suppose there are 4 CPUs and policy->cpu=CPU0, CPU1/2/3 are linked to CPU0. The normal sequence is: 1) Current governor is userspace. An application tries to set the governor to ondemand. It will call __cpufreq_set_policy() in which it will stop the userspace governor and then start the ondemand governor. 2) Current governor is userspace. The online of CPU3 runs on CPU0. It will call cpufreq_add_policy_cpu() in which it will first stop the userspace governor, and then start it again. If the sequence of the above two cases interleaves, it becomes: 1) Application stops userspace governor 2) Hotplug stops userspace governor which is a problem, because the governor shouldn't be stopped twice in a row. What happens next is: 3) Application starts ondemand governor 4) Hotplug starts a governor In step 4, the hotplug is supposed to start the userspace governor, but now the governor has been changed by the application to ondemand, so the ondemand governor is started once again, which is incorrect. The solution is to prevent policy governors from being stopped multiple times in a row. A governor should only be stopped once for one policy. After it has been stopped, no more governor stop operations should be executed. Also add a mutex to serialize governor operations. [rjw: Changelog. And you owe me a beverage of my choice.] Signed-off-by: Xiaoguang Chen <chenxg@marvell.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-14cpufreq: remove CONFIG_CPU_FREQ_TABLEViresh Kumar
CONFIG_CPU_FREQ_TABLE will be always enabled when cpufreq framework is used, as cpufreq core depends on it. So, we don't need this CONFIG option anymore as it is not configurable. Remove CONFIG_CPU_FREQ_TABLE and update its users. Change-Id: I40db00061a924631f0eb2fc090b9e543d9069605 Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Paul Walmsley <pwalmsley@nvidia.com> # for the NVIDIA downstream kernel Reviewed-on: http://git-master/r/356889 Reviewed-by: Aleksandr Frid <afrid@nvidia.com> Reviewed-by: Diwakar Tundlam <dtundlam@nvidia.com>
2013-10-31cpufreq: don't allow governor limits to be changed when it is disabledViresh Kumar
__cpufreq_governor() returns with -EBUSY when governor is already stopped and we try to stop it again, but when it is stopped we must not allow calls to CPUFREQ_GOV_LIMITS event as well. This patch adds this check in __cpufreq_governor(). Bug 1371564 Reported-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> (cherry picked from commit f73d39338444d9915c746403bd98b145ff9d2ba4) Signed-off-by: Puneet Saxena <puneets@nvidia.com> Change-Id: Iba25d40c8bc12d7030e60d35b0fa1a6042ebeacf Reviewed-on: http://git-master/r/309652 Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com> Tested-by: Bharat Nihalani <bnihalani@nvidia.com>
2013-10-14cpufreq: Fix tracing for CPU scalingAntti P Miettinen
Make sure that CPU frequency change requests get always traced. Change-Id: I69c70150f44bb3baf934ca08a7cbe1c86fe3e135 Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com> Reviewed-on: http://git-master/r/298730 Reviewed-by: Automatic_Commit_Validation_User Reviewed-by: Juha Tukkinen <jtukkinen@nvidia.com>
2013-09-25cpufreq: Move get_cpu_idle_time() to cpufreq.cViresh Kumar
Governors other than ondemand and conservative can also use get_cpu_idle_time() and they aren't required to compile cpufreq_governor.c. So, move these independent routines to cpufreq.c instead. Bug 1367411 Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> (cherry picked from commit a5d035da3acfefcebc2608cdc40c5f1e89784ede) Signed-off-by: Shridhar Rasal <srasal@nvidia.com> Change-Id: I6e0c371ec345d060ea748da182524428dd6231de Reviewed-on: http://git-master/r/276655 Reviewed-by: Automatic_Commit_Validation_User Reviewed-by: Shridhar Rasal <srasal@nvidia.com> Tested-by: Shridhar Rasal <srasal@nvidia.com> Reviewed-by: Ajay Nandakumar M <anandakumarm@nvidia.com> Reviewed-by: Puneet Saxena <puneets@nvidia.com> Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
2013-09-25cpufreq: governors: Move get_governor_parent_kobj() to cpufreq.cViresh Kumar
get_governor_parent_kobj() can be used by any governor, generic cpufreq governors or platform specific ones and so must be present in cpufreq.c instead of cpufreq_governor.c. This patch moves it to cpufreq.c. This also adds EXPORT_SYMBOL_GPL(get_governor_parent_kobj) so that modules can use this function too. Bug 1367411 Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> (cherry picked from commit 69bbfa930a4b93beae124e10566d37d1ab3d07af) Signed-off-by: Shridhar Rasal <srasal@nvidia.com> Change-Id: I5d5efb998321c939667189920698685d749da59d Reviewed-on: http://git-master/r/276654 Reviewed-by: Automatic_Commit_Validation_User Reviewed-by: Shridhar Rasal <srasal@nvidia.com> Tested-by: Shridhar Rasal <srasal@nvidia.com> Reviewed-by: Puneet Saxena <puneets@nvidia.com> Tested-by: Puneet Saxena <puneets@nvidia.com> Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
2013-09-25cpufreq: Add EXPORT_SYMBOL_GPL for have_governor_per_policyViresh Kumar
This patch adds: EXPORT_SYMBOL_GPL(have_governor_per_policy), so that this routine can be used by modules too. Bug 1367411 Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> (cherry picked from commit 7997332019e336d9b05b846aa0d04910dcd2e860) Signed-off-by: Shridhar Rasal <srasal@nvidia.com> Change-Id: I2b15ce2efffaf7adc735f8d7c09cc594d58cfa27 Reviewed-on: http://git-master/r/276652 Reviewed-by: Automatic_Commit_Validation_User Reviewed-by: Dan Willemsen <dwillemsen@nvidia.com> Reviewed-by: Puneet Saxena <puneets@nvidia.com>
2013-09-14cpufreq: Fix governor start/stop race conditionXiaoguang Chen
Cpufreq governors' stop and start operations should be carried out in sequence. Otherwise, there will be unexpected behavior, like in the example below. Suppose there are 4 CPUs and policy->cpu=CPU0, CPU1/2/3 are linked to CPU0. The normal sequence is: 1) Current governor is userspace. An application tries to set the governor to ondemand. It will call __cpufreq_set_policy() in which it will stop the userspace governor and then start the ondemand governor. 2) Current governor is userspace. The online of CPU3 runs on CPU0. It will call cpufreq_add_policy_cpu() in which it will first stop the userspace governor, and then start it again. If the sequence of the above two cases interleaves, it becomes: 1) Application stops userspace governor 2) Hotplug stops userspace governor which is a problem, because the governor shouldn't be stopped twice in a row. What happens next is: 3) Application starts ondemand governor 4) Hotplug starts a governor In step 4, the hotplug is supposed to start the userspace governor, but now the governor has been changed by the application to ondemand, so the ondemand governor is started once again, which is incorrect. The solution is to prevent policy governors from being stopped multiple times in a row. A governor should only be stopped once for one policy. After it has been stopped, no more governor stop operations should be executed. Also add a mutex to serialize governor operations. [rjw: Changelog. And you owe me a beverage of my choice.] Bug 1362600 Signed-off-by: Xiaoguang Chen <chenxg@marvell.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> (cherry picked from commit 95731ebb114c5f0c028459388560fc2a72fe5049) Change-Id: Id25906af79fc9da02fa358695605b7355527b59f Signed-off-by: Ajay Nandakumar <anandakumarm@nvidia.com> Reviewed-on: http://git-master/r/274280 Reviewed-by: Shridhar Rasal <srasal@nvidia.com> Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com> Tested-by: Bharat Nihalani <bnihalani@nvidia.com>
2013-09-14cpufreq: Fix tracingAntti P Miettinen
Trace scaling end also for the case when frequency does not change. Change-Id: Ifd3cd974d5a2f498174f3b716769cf0173bd32da Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com> Reviewed-on: http://git-master/r/242367 Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
2013-09-14cpufreq: 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> Rebase-Id: R24af1f7d5e3c847ff57b1cbc2b2917591df2b0d5
2013-09-14cpufreq: 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> Rebase-Id: R86b13b0253d70595c37d835ffdc809d9f7172e8f
2013-09-14cpufreq: 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> Rebase-Id: Rb3099a95700c83e412808b91da1c076f0873722c
2013-09-14tracing: 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> Rebase-Id: R4163876146ae25dc948985fd27143ac91644448b
2013-09-14cpufreq: 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> Rebase-Id: Rf996a487f263e4bee451da38d3317a6ae53214dd
2013-09-14cpufreq: 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> Rebase-Id: Rcdb51f6b884ccd3d6324de5569dc0ecf4994c3f0
2013-09-14cpufreq: 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 Rebase-Id: Ra33b58958c1251c5931e84c2a81726fe9b5b1e92
2013-09-14cpufreq: 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 Rebase-Id: Red1299253123d231af705a130f07e7aa77698fd8
2013-09-14cpufreq: 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 Rebase-Id: Rf145967a22a5d871d01bb1334a2e7d366a6612fd
2013-09-13Revert "cpufreq: Notify all policy->cpus in cpufreq_notify_transition()"Dan Willemsen
This reverts commit b43a7ffbf33be7e4d3b10b7714ee663ea2c52fe2. Signed-off-by: Dan Willemsen <dwillemsen@nvidia.com>
2013-08-11cpufreq: Fix cpufreq driver module refcount balance after suspend/resumeRafael J. Wysocki
commit 2a99859932281ed6c2ecdd988855f8f6838f6743 upstream. Since cpufreq_cpu_put() called by __cpufreq_remove_dev() drops the driver module refcount, __cpufreq_remove_dev() causes that refcount to become negative for the cpufreq driver after a suspend/resume cycle. This is not the only bad thing that happens there, however, because kobject_put() should only be called for the policy kobject at this point if the CPU is not the last one for that policy. Namely, if the given CPU is the last one for that policy, the policy kobject's refcount should be 1 at this point, as set by cpufreq_add_dev_interface(), and only needs to be dropped once for the kobject to go away. This actually happens under the cpu == 1 check, so it need not be done before by cpufreq_cpu_put(). On the other hand, if the given CPU is not the last one for that policy, this means that cpufreq_add_policy_cpu() has been called at least once for that policy and cpufreq_cpu_get() has been called for it too. To balance that cpufreq_cpu_get(), we need to call cpufreq_cpu_put() in that case. Thus, to fix the described problem and keep the reference counters balanced in both cases, move the cpufreq_cpu_get() call in __cpufreq_remove_dev() to the code path executed only for CPUs that share the policy with other CPUs. Reported-and-tested-by: Toralf Förster <toralf.foerster@gmx.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-25cpufreq: Revert commit a66b2e to fix suspend/resume regressionSrivatsa S. Bhat
commit aae760ed21cd690fe8a6db9f3a177ad55d7e12ab upstream. commit a66b2e (cpufreq: Preserve sysfs files across suspend/resume) has unfortunately caused several things in the cpufreq subsystem to break subtly after a suspend/resume cycle. The intention of that patch was to retain the file permissions of the cpufreq related sysfs files across suspend/resume. To achieve that, the commit completely removed the calls to cpufreq_add_dev() and __cpufreq_remove_dev() during suspend/resume transitions. But the problem is that those functions do 2 kinds of things: 1. Low-level initialization/tear-down that are critical to the correct functioning of cpufreq-core. 2. Kobject and sysfs related initialization/teardown. Ideally we should have reorganized the code to cleanly separate these two responsibilities, and skipped only the sysfs related parts during suspend/resume. Since we skipped the entire callbacks instead (which also included some CPU and cpufreq-specific critical components), cpufreq subsystem started behaving erratically after suspend/resume. So revert the commit to fix the regression. We'll revisit and address the original goal of that commit separately, since it involves quite a bit of careful code reorganization and appears to be non-trivial. (While reverting the commit, note that another commit f51e1eb (cpufreq: Fix cpufreq regression after suspend/resume) already reverted part of the original set of changes. So revert only the remaining ones). Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-22cpufreq: Drop rwsem lock around CPUFREQ_GOV_POLICY_EXITViresh Kumar
With the rwsem lock around __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT), we get circular dependency when we call sysfs_remove_group(). ====================================================== [ INFO: possible circular locking dependency detected ] 3.9.0-rc7+ #15 Not tainted ------------------------------------------------------- cat/2387 is trying to acquire lock: (&per_cpu(cpu_policy_rwsem, cpu)){+++++.}, at: [<c02f6179>] lock_policy_rwsem_read+0x25/0x34 but task is already holding lock: (s_active#41){++++.+}, at: [<c00f9bf7>] sysfs_read_file+0x4f/0xcc which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (s_active#41){++++.+}: [<c0055a79>] lock_acquire+0x61/0xbc [<c00fabf1>] sysfs_addrm_finish+0xc1/0x128 [<c00f9819>] sysfs_hash_and_remove+0x35/0x64 [<c00fbe6f>] remove_files.isra.0+0x1b/0x24 [<c00fbea5>] sysfs_remove_group+0x2d/0xa8 [<c02f9a0b>] cpufreq_governor_interactive+0x13b/0x35c [<c02f61df>] __cpufreq_governor+0x2b/0x8c [<c02f6579>] __cpufreq_set_policy+0xa9/0xf8 [<c02f6b75>] store_scaling_governor+0x61/0x100 [<c02f6f4d>] store+0x39/0x60 [<c00f9b81>] sysfs_write_file+0xed/0x114 [<c00b3fd1>] vfs_write+0x65/0xd8 [<c00b424b>] sys_write+0x2f/0x50 [<c000cdc1>] ret_fast_syscall+0x1/0x52 -> #0 (&per_cpu(cpu_policy_rwsem, cpu)){+++++.}: [<c0055253>] __lock_acquire+0xef3/0x13dc [<c0055a79>] lock_acquire+0x61/0xbc [<c03ee1f5>] down_read+0x25/0x30 [<c02f6179>] lock_policy_rwsem_read+0x25/0x34 [<c02f6edd>] show+0x21/0x58 [<c00f9c0f>] sysfs_read_file+0x67/0xcc [<c00b40a7>] vfs_read+0x63/0xd8 [<c00b41fb>] sys_read+0x2f/0x50 [<c000cdc1>] ret_fast_syscall+0x1/0x52 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(s_active#41); lock(&per_cpu(cpu_policy_rwsem, cpu)); lock(s_active#41); lock(&per_cpu(cpu_policy_rwsem, cpu)); *** DEADLOCK *** 2 locks held by cat/2387: #0: (&buffer->mutex){+.+.+.}, at: [<c00f9bcd>] sysfs_read_file+0x25/0xcc #1: (s_active#41){++++.+}, at: [<c00f9bf7>] sysfs_read_file+0x4f/0xcc stack backtrace: [<c0011d55>] (unwind_backtrace+0x1/0x9c) from [<c03e9a09>] (print_circular_bug+0x19d/0x1e8) [<c03e9a09>] (print_circular_bug+0x19d/0x1e8) from [<c0055253>] (__lock_acquire+0xef3/0x13dc) [<c0055253>] (__lock_acquire+0xef3/0x13dc) from [<c0055a79>] (lock_acquire+0x61/0xbc) [<c0055a79>] (lock_acquire+0x61/0xbc) from [<c03ee1f5>] (down_read+0x25/0x30) [<c03ee1f5>] (down_read+0x25/0x30) from [<c02f6179>] (lock_policy_rwsem_read+0x25/0x34) [<c02f6179>] (lock_policy_rwsem_read+0x25/0x34) from [<c02f6edd>] (show+0x21/0x58) [<c02f6edd>] (show+0x21/0x58) from [<c00f9c0f>] (sysfs_read_file+0x67/0xcc) [<c00f9c0f>] (sysfs_read_file+0x67/0xcc) from [<c00b40a7>] (vfs_read+0x63/0xd8) [<c00b40a7>] (vfs_read+0x63/0xd8) from [<c00b41fb>] (sys_read+0x2f/0x50) [<c00b41fb>] (sys_read+0x2f/0x50) from [<c000cdc1>] (ret_fast_syscall+0x1/0x52) This lock isn't required while calling __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT). Remove it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-15cpufreq: Preserve sysfs files across suspend/resumeSrivatsa S. Bhat
The file permissions of cpufreq per-cpu sysfs files are not preserved across suspend/resume because we internally go through the CPU Hotplug path which reinitializes the file permissions on CPU online. But the user is not supposed to know that we are using CPU hotplug internally within suspend/resume (IOW, the kernel should not silently wreck the user-set file permissions across a suspend cycle). Therefore, we need to preserve the file permissions as they are across suspend/resume. The simplest way to achieve that is to just not touch the sysfs files at all - ie., just ignore the CPU hotplug notifications in the suspend/resume path (_FROZEN) in the cpufreq hotplug callback. Reported-by: Robert Jarzmik <robert.jarzmik@intel.com> Reported-by: Durgadoss R <durgadoss.r@intel.com> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-12cpufreq: Issue CPUFREQ_GOV_POLICY_EXIT notifier before dropping policy refcountViresh Kumar
We must call __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT) before calling cpufreq_cpu_put(data), so that policy kobject have valid fields. Otherwise, removing last online cpu of policy->cpus causes this crash for ondemand/conservative governor. [<c00fb076>] (sysfs_find_dirent+0xe/0xa8) from [<c00fb1bd>] (sysfs_get_dirent+0x21/0x58) [<c00fb1bd>] (sysfs_get_dirent+0x21/0x58) from [<c00fc259>] (sysfs_remove_group+0x85/0xbc) [<c00fc259>] (sysfs_remove_group+0x85/0xbc) from [<c02faad9>] (cpufreq_governor_dbs+0x369/0x4a0) [<c02faad9>] (cpufreq_governor_dbs+0x369/0x4a0) from [<c02f66d7>] (__cpufreq_governor+0x2b/0x8c) [<c02f66d7>] (__cpufreq_governor+0x2b/0x8c) from [<c02f6893>] (__cpufreq_remove_dev.isra.12+0x15b/0x250) [<c02f6893>] (__cpufreq_remove_dev.isra.12+0x15b/0x250) from [<c03e91c7>] (cpufreq_cpu_callback+0x2f/0x3c) [<c03e91c7>] (cpufreq_cpu_callback+0x2f/0x3c) from [<c0036fe1>] (notifier_call_chain+0x45/0x54) [<c0036fe1>] (notifier_call_chain+0x45/0x54) from [<c001e611>] (__cpu_notify+0x1d/0x34) [<c001e611>] (__cpu_notify+0x1d/0x34) from [<c03e5833>] (_cpu_down+0x63/0x1ac) [<c03e5833>] (_cpu_down+0x63/0x1ac) from [<c03e5997>] (cpu_down+0x1b/0x30) [<c03e5997>] (cpu_down+0x1b/0x30) from [<c03e60eb>] (store_online+0x27/0x54) [<c03e60eb>] (store_online+0x27/0x54) from [<c0295629>] (dev_attr_store+0x11/0x18) [<c0295629>] (dev_attr_store+0x11/0x18) from [<c00f9edd>] (sysfs_write_file+0xed/0x114) [<c00f9edd>] (sysfs_write_file+0xed/0x114) from [<c00b42a9>] (vfs_write+0x65/0xd8) [<c00b42a9>] (vfs_write+0x65/0xd8) from [<c00b4523>] (sys_write+0x2f/0x50) [<c00b4523>] (sys_write+0x2f/0x50) from [<c000cdc1>] (ret_fast_syscall+0x1/0x52) Of course this only impacted drivers which have have_governor_per_policy set to true. i.e. big LITTLE cpufreq driver. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-29cpufreq: Revert incorrect commit 5800043Rafael J. Wysocki
Commit 5800043 (cpufreq: convert cpufreq_driver to using RCU) causes the following call trace to be spit on boot: BUG: sleeping function called from invalid context at /scratch/rafael/work/linux-pm/mm/slab.c:3179 in_atomic(): 0, irqs_disabled(): 0, pid: 292, name: systemd-udevd 2 locks held by systemd-udevd/292: #0: (subsys mutex){+.+.+.}, at: [<ffffffff8146851a>] subsys_interface_register+0x4a/0xe0 #1: (rcu_read_lock){.+.+.+}, at: [<ffffffff81538210>] cpufreq_add_dev_interface+0x60/0x5e0 Pid: 292, comm: systemd-udevd Not tainted 3.9.0-rc8+ #323 Call Trace: [<ffffffff81072c90>] __might_sleep+0x140/0x1f0 [<ffffffff811581c2>] kmem_cache_alloc+0x42/0x2b0 [<ffffffff811e7179>] sysfs_new_dirent+0x59/0x130 [<ffffffff811e63cb>] sysfs_add_file_mode+0x6b/0x110 [<ffffffff81538210>] ? cpufreq_add_dev_interface+0x60/0x5e0 [<ffffffff810a3254>] ? __lock_is_held+0x54/0x80 [<ffffffff811e647d>] sysfs_add_file+0xd/0x10 [<ffffffff811e6541>] sysfs_create_file+0x21/0x30 [<ffffffff81538280>] cpufreq_add_dev_interface+0xd0/0x5e0 [<ffffffff81538210>] ? cpufreq_add_dev_interface+0x60/0x5e0 [<ffffffffa000337f>] ? acpi_processor_get_platform_limit+0x32/0xbb [processor] [<ffffffffa022f540>] ? do_drv_write+0x70/0x70 [acpi_cpufreq] [<ffffffff810a3254>] ? __lock_is_held+0x54/0x80 [<ffffffff8106c97e>] ? up_read+0x1e/0x40 [<ffffffff8106e632>] ? __blocking_notifier_call_chain+0x72/0xc0 [<ffffffff81538dbd>] cpufreq_add_dev+0x62d/0xae0 [<ffffffff815389b8>] ? cpufreq_add_dev+0x228/0xae0 [<ffffffff81468569>] subsys_interface_register+0x99/0xe0 [<ffffffffa014d000>] ? 0xffffffffa014cfff [<ffffffff81535d5d>] cpufreq_register_driver+0x9d/0x200 [<ffffffffa014d000>] ? 0xffffffffa014cfff [<ffffffffa014d0e9>] acpi_cpufreq_init+0xe9/0x1000 [acpi_cpufreq] [<ffffffff810002fa>] do_one_initcall+0x11a/0x170 [<ffffffff810b4b87>] load_module+0x1cf7/0x2920 [<ffffffff81322580>] ? ddebug_proc_open+0xb0/0xb0 [<ffffffff816baee0>] ? retint_restore_args+0xe/0xe [<ffffffff810b5887>] sys_init_module+0xd7/0x120 [<ffffffff816bb6d2>] system_call_fastpath+0x16/0x1b which is quite obvious, because that commit put (multiple instances of) sysfs_create_file() under rcu_read_lock()/rcu_read_unlock(), although sysfs_create_file() may cause memory to be allocated with GFP_KERNEL and that may sleep, which is not permitted in RCU read critical section. Revert the buggy commit altogether along with some changes on top of it. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-22cpufreq: Don't call __cpufreq_governor() for drivers without target()Viresh Kumar
Some cpufreq drivers implement their own governor and so don't need us to call generic governors interface via __cpufreq_governor(). Few recent commits haven't obeyed this law well and we saw some regressions. This patch is an attempt to fix the above issue. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reported-and-tested-by: Sedat Dilek <sedat.dilek@gmail.com> Tested-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-11cpufreq: Call __cpufreq_governor() with correct policy->cpus maskViresh Kumar
__cpufreq_governor() must be called with a correct policy->cpus mask. In __cpufreq_remove_dev() we initially clear policy->cpus with cpumask_clear_cpu() and then call __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT). If the governor is doing some per-cpu stuff in EXIT callback, this can create uncertain behavior. Generic governors in drivers/cpufreq/ doesn't do any per-cpu stuff in EXIT callback and so we don't face any issues currently. But its better to keep the code clean, so we don't face any issues in future. Now, we call cpumask_clear_cpu() only when multiple cpus are managed by policy. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-10cpufreq: convert cpufreq_driver to using RCUNathan Zimmer
We eventually would like to remove the rwlock cpufreq_driver_lock or convert it back to a spinlock and protect the read sections with RCU. The first step in that direction is to make cpufreq_driver use RCU. I don't see an easy wasy to protect the cpufreq_cpu_data structure with RCU, so I am leaving it with the rwlock for now since under certain configs __cpufreq_cpu_get is a hot spot with 256+ cores. [rjw: Subject, changelog, white space] Signed-off-by: Nathan Zimmer <nzimmer@sgi.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-02cpufreq: Notify all policy->cpus in cpufreq_notify_transition()Viresh Kumar
policy->cpus contains all online cpus that have single shared clock line. And their frequencies are always updated together. Many SMP system's cpufreq drivers take care of this in individual drivers but the best place for this code is in cpufreq core. This patch modifies cpufreq_notify_transition() to notify frequency change for all cpus in policy->cpus and hence updates all users of this API. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Stephen Warren <swarren@nvidia.com> Tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-01cpufreq: governor: Implement per policy instances of governorsViresh Kumar
Currently, there can't be multiple instances of single governor_type. If we have a multi-package system, where we have multiple instances of struct policy (per package), we can't have multiple instances of same governor. i.e. We can't have multiple instances of ondemand governor for multiple packages. Governors directory in sysfs is created at /sys/devices/system/cpu/cpufreq/ governor-name/. Which again reflects that there can be only one instance of a governor_type in the system. This is a bottleneck for multicluster system, where we want different packages to use same governor type, but with different tunables. This patch uses the infrastructure provided by earlier patch and implements init/exit routines for ondemand and conservative governors. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-01cpufreq: Add per policy governor-init/exit infrastructureViresh Kumar
Currently, there can't be multiple instances of single governor_type. If we have a multi-package system, where we have multiple instances of struct policy (per package), we can't have multiple instances of same governor. i.e. We can't have multiple instances of ondemand governor for multiple packages. Governors directory in sysfs is created at /sys/devices/system/cpu/cpufreq/ governor-name/. Which again reflects that there can be only one instance of a governor_type in the system. This is a bottleneck for multicluster system, where we want different packages to use same governor type, but with different tunables. This patch is inclined towards providing this infrastructure. Because we are required to allocate governor's resources dynamically now, we must do it at policy creation and end. And so got CPUFREQ_GOV_POLICY_INIT/EXIT. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-01cpufreq: Convert the cpufreq_driver_lock to a rwlockNathan Zimmer
This eliminates the contention I am seeing in __cpufreq_cpu_get. It also nicely stages the lock to be replaced by the rcu. Signed-off-by: Nathan Zimmer <nzimmer@sgi.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-15Merge branch 'pm-cpufreq'Rafael J. Wysocki
* pm-cpufreq: (55 commits) cpufreq / intel_pstate: Fix 32 bit build cpufreq: conservative: Fix typos in comments cpufreq: ondemand: Fix typos in comments cpufreq: exynos: simplify .init() for setting policy->cpus cpufreq: kirkwood: Add a cpufreq driver for Marvell Kirkwood SoCs cpufreq/x86: Add P-state driver for sandy bridge. cpufreq_stats: do not remove sysfs files if frequency table is not present cpufreq: Do not track governor name for scaling drivers with internal governors. cpufreq: Only call cpufreq_out_of_sync() for driver that implement cpufreq_driver.target() cpufreq: Retrieve current frequency from scaling drivers with internal governors cpufreq: Fix locking issues cpufreq: Create a macro for unlock_policy_rwsem{read,write} cpufreq: Remove unused HOTPLUG_CPU code cpufreq: governors: Fix WARN_ON() for multi-policy platforms cpufreq: ondemand: Replace down_differential tuner with adj_up_threshold cpufreq / stats: Get rid of CPUFREQ_STATDEVICE_ATTR cpufreq: Don't check cpu_online(policy->cpu) cpufreq: add imx6q-cpufreq driver cpufreq: Don't remove sysfs link for policy->cpu cpufreq: Remove unnecessary use of policy->shared_type ...
2013-02-09cpufreq: Do not track governor name for scaling drivers with internal governors.Dirk Brandewie
Scaling drivers that implement internal governors do not have governor structures assocaited with them. Only track the name of the governor associated with the CPU if the driver does not implement cpufreq_driver.setpolicy() Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-09cpufreq: Only call cpufreq_out_of_sync() for driver that implement ↵Dirk Brandewie
cpufreq_driver.target() Scaling drivers that implement cpufreq_driver.setpolicy() have internal governors that do not signal changes via cpufreq_notify_transition() so the frequncy in the policy will almost certainly be different than the current frequncy. Only call cpufreq_out_of_sync() when the underlying driver implements cpufreq_driver.target() Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-09cpufreq: Retrieve current frequency from scaling drivers with internal governorsDirk Brandewie
Scaling drivers that implement the cpufreq_driver.setpolicy() versus the cpufreq_driver.target() interface do not set policy->cur. Normally policy->cur is set during the call to cpufreq_driver.target() when the frequnecy request is made by the governor. If the scaling driver implements cpufreq_driver.setpolicy() and cpufreq_driver.get() interfaces use cpufreq_driver.get() to retrieve the current frequency. Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-09cpufreq: Fix locking issuesViresh Kumar
cpufreq core uses two locks: - cpufreq_driver_lock: General lock for driver and cpufreq_cpu_data array. - cpu_policy_rwsemfix locking: per CPU reader-writer semaphore designed to cure all cpufreq/hotplug/workqueue/etc related lock issues. These locks were not used properly and are placed against their principle (present before their definition) at various places. This patch is an attempt to fix their use. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-09cpufreq: Create a macro for unlock_policy_rwsem{read,write}Viresh Kumar
On the lines of macro: lock_policy_rwsem, we can create another macro for unlock_policy_rwsem. Lets do it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-09cpufreq: Remove unused HOTPLUG_CPU codeViresh Kumar
Because the sibling cpu of any online cpu is identified very early in cpufreq_add_dev(), below code is never executed. And so can be removed. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-09cpufreq: governors: Fix WARN_ON() for multi-policy platformsViresh Kumar
On multi-policy systems there is a single instance of governor for both the policies (if same governor is chosen for both policies). With the code update from following patches: 8eeed09 cpufreq: governors: Get rid of dbs_data->enable field b394058 cpufreq: governors: Reset tunables only for cpufreq_unregister_governor() We are creating/removing sysfs directory of governor for for every call to GOV_START and STOP. This would fail for multi-policy system as there is a per-policy call to START/STOP. This patch reuses the governor->initialized variable to detect total users of governor. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-09cpufreq: Don't check cpu_online(policy->cpu)Viresh Kumar
policy->cpu or cpus in policy->cpus can't be offline anymore. And so we don't need to check if they are online or not. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-05cpufreq: Don't remove sysfs link for policy->cpuViresh Kumar
"cpufreq" directory in policy->cpu is never created using sysfs_create_link(), but using kobject_init_and_add(). And so we shouldn't call sysfs_remove_link() for policy->cpu(). sysfs stuff for policy->cpu is automatically removed when we call kobject_put() for dying policy. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-02cpufreq: governors: Reset tunables only for cpufreq_unregister_governor()Viresh Kumar
Currently, whenever governor->governor() is called for CPUFRREQ_GOV_START event we reset few tunables of governor. Which isn't correct, as this routine is called for every cpu hot-[un]plugging event. We should actually be resetting these only when the governor module is removed and re-installed. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-02cpufreq: Simplify cpufreq_add_dev()Viresh Kumar
Currently cpufreq_add_dev() firsts allocates policy, calls driver->init() and then checks if this CPU is already managed or not. And if it is already managed, its policy is freed. We can save all this if we somehow know that CPU is managed or not in advance. policy->related_cpus contains the list of all valid sibling CPUs of policy->cpu. We can check this to see if the current CPU is already managed. From now on, platforms don't really need to set related_cpus from their init() routines, as the same work is done by core too. If a platform driver needs to set the related_cpus mask with some additional CPUs, other than CPUs present in policy->cpus, they are free to do it, though, as we don't override anything. [rjw: Changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-02cpufreq: Revert "cpufreq: Don't use cpu removed during ↵Viresh Kumar
cpufreq_driver_unregister" This reverts commit 956f339 "cpufreq: Don't use cpu removed during cpufreq_driver_unregister". With the addition of the following commit, this change/variable is not required any more: commit b9ba2725343ae57add3f324dfa5074167f48de96 Author: Viresh Kumar <viresh.kumar@linaro.org> Date: Mon Jan 14 13:23:03 2013 +0000 cpufreq: Simplify __cpufreq_remove_dev() [rjw: Subject and changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-02cpufreq: Add a get_current_driver helperBorislav Petkov
Add a helper function to return cpufreq_driver->name. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-02cpufreq: handle cpufreq being disabled for all exported function.Dirk Brandewie
When disable_cpufreq() is called some exported functions are still being used that do not have a check for cpufreq being disabled. Add a disabled check into cpufreq_cpu_get() to return NULL if cpufreq is disabled this covers most of the exported functions. For the exported functions that do not call cpufreq_cpu_get() add an explicit check. Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-02cpufreq: Simplify __cpufreq_remove_dev()Viresh Kumar
__cpufreq_remove_dev() is called on multiple occasions: cpufreq_driver unregister and cpu removals. Current implementation of this routine is overly complex without much need. If the cpu to be removed is the policy->cpu, we remove the policy first and add all other cpus again from policy->cpus and then finally call __cpufreq_remove_dev() again to remove the cpu to be deleted. Haahhhh.. There exist a simple solution to removal of a cpu: - Simply use the old policy structure - update its fields like: policy->cpu, etc. - notify any users of cpufreq, which depend on changing policy->cpu Hence this patch, which tries to implement the above theory. It is tested well by myself on ARM big.LITTLE TC2 SoC, which has 5 cores (2 A15 and 3 A7). Both A15's share same struct policy and all A7's share same policy structure. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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