user/sven/linux.git/drivers/cpufreq/cpufreq_userspace.c, branch v3.3.5

[CPUFREQ] cpufreq:userspace: fix cpu_cur_freq updation

2012-01-06T15:10:53Z

CPU frequency is guranteed to be changed on notifier callback with CPUFREQ_POSTCHANGE. Notifier callback with CPUFREQ_PRECHANGE does not gurantee a change in frequency; after it, if cpufreq driver is unable to change CPU to new frequency. This results in wrong information being fed to user (if setting CPU frequency fails) upon doing like, cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed Hence in userspace governer update cpu_cur_freq only if notifier has been called with POSTCHANGE. Signed-off-by: Afzal Mohammed Signed-off-by: Dave Jones

[CPUFREQ] use dynamic debug instead of custom infrastructure

2011-05-04T15:50:57Z

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 Signed-off-by: Dave Jones

[CPUFREQ] checkpatch cleanups for userspace governor

2009-02-25T03:47:30Z

Signed-off-by: Dave Jones

[CPUFREQ] Don't export governors for default governor

2008-10-09T17:52:44Z

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 Signed-off-by: Dave Jones

NR_CPUS: Replace NR_CPUS in cpufreq userspace routines

2008-07-20T08:21:11Z

* Replace arrays sized by NR_CPUS with percpu variables. Prior reference: http://marc.info/?l=linux-kernel&m=120251421825989&w=4 Subject: [PATCH 1/4] cpufreq: change cpu freq tables to per_cpu variables From: Mike Travis Date: 2008-02-08 23:37:39 Signed-off-by: Mike Travis Signed-off-by: Ingo Molnar

[CPUFREQ] Eliminate cpufreq_userspace scaling_setspeed deadlock

2008-02-07T03:57:58Z

Eliminate cpufreq_userspace scaling_setspeed deadlock. Luming Yu recently uncovered yet another cpufreq related deadlock. One thread that continuously switches the governors and the other thread that repeatedly cats the contents of cpufreq directory causes both these threads to go into a deadlock. Detailed examination of the deadlock showed the exact flow before the deadlock as: Thread 1 Thread 2 ________ ________ cats files under /sys/devices/.../cpufreq/ Set governor to userspace Adds a new sysfs entry for scaling_setspeed cats files under /sys/devices/.../cpufreq/ Set governor to performance Holds cpufreq_rw_sem in write mode Sends a STOP notify to userspace governor cat /sys/devices/.../cpufreq/scaling_setspeed Gets a handle on the above sysfs entry with sysfs_get_active Blocks while trying to get cpufreq_rw_sem in read mode Remove a sysfs entry for scaling_setspeed Blocks on sysfs_deactivate while waiting for earlier get_active (on other thread) to drain At this point both threads go into deadlock and any other thread that tries to do anything with sysfs cpufreq will also block. There seems to be no easy way to avoid this deadlock as long as cpufreq_userspace adds/removes the sysfs entry under same kobject as cpufreq. Below patch moves scaling_setspeed to cpufreq.c, keeping it always and calling back the governor on read/write. This is the cleanest fix I could think of, even though adding two callbacks in governor structure just for this seems unnecessary. Note that the change makes scaling_setspeed under /sys/.../cpufreq permanent and returns when governor is not userspace. Signed-off-by: Venkatesh Pallipadi Signed-off-by: Dave Jones

cpufreq: Initialise default governor before use

2008-01-17T23:38:58Z

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 Cc: Dave Jones Cc: "Rafael J. Wysocki" Cc: Venkatesh Pallipadi Acked-by: Ingo Molnar Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq

2007-07-12T20:42:43Z

* master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq: [CPUFREQ] Fix sysfs_create_file return value handling [CPUFREQ] ondemand: fix tickless accounting and software coordination bug [CPUFREQ] ondemand: add a check to avoid negative load calculation [CPUFREQ] Keep userspace governor quiet when it is not being used [CPUFREQ] Longhaul - Proper register access [CPUFREQ] Kconfig powernow-k8 driver should depend on ACPI P-States driver [CPUFREQ] Longhaul - Replace ACPI functions with direct I/O [CPUFREQ] Longhaul - Remove duplicate multipliers [CPUFREQ] Longhaul - Embedded "conservative" [CPUFREQ] acpi-cpufreq: Proper ReadModifyWrite of PERF_CTL MSR [CPUFREQ] check return value of sysfs_create_file [CPUFREQ] Longhaul - Check ACPI "BM DMA in progress" bit [CPUFREQ] Longhaul - Move old_ratio to correct place [CPUFREQ] Longhaul - VT8237 support [CPUFREQ] Longhaul - Use all kinds of support [CPUFREQ] powernow-k8: clarify number of cores.

sysfs: kill unnecessary attribute->owner

2007-07-11T23:09:06Z

sysfs is now completely out of driver/module lifetime game. After deletion, a sysfs node doesn't access anything outside sysfs proper, so there's no reason to hold onto the attribute owners. Note that often the wrong modules were accounted for as owners leading to accessing removed modules. This patch kills now unnecessary attribute->owner. Note that with this change, userland holding a sysfs node does not prevent the backing module from being unloaded. For more info regarding lifetime rule cleanup, please read the following message. http://article.gmane.org/gmane.linux.kernel/510293 (tweaked by Greg to not delete the field just yet, to make it easier to merge things properly.) Signed-off-by: Tejun Heo Cc: Cornelia Huck Cc: Andrew Morton Signed-off-by: Greg Kroah-Hartman

[CPUFREQ] Keep userspace governor quiet when it is not being used

2007-06-21T16:57:53Z

Userspace governor registers a frequency change notifier at init time, even when no CPU is set to userspace governor. Make it register only when atleast one CPU is using userspace. Signed-off-by: Venkatesh Pallipadi Signed-off-by: Dave Jones