aboutsummaryrefslogtreecommitdiff
path: root/drivers/cpufreq
AgeCommit message (Collapse)Author
2005-11-09[PATCH] cpu hotplug: fix locking in cpufreq driversAshok Raj
When calling target drivers to set frequency, we take cpucontrol lock. When we modified the code to accomodate CPU hotplug, there was an attempt to take a double lock of cpucontrol leading to a deadlock. Since the current thread context is already holding the cpucontrol lock, we dont need to make another attempt to acquire it. Now we leave a trace in current->flags indicating current thread already is under cpucontrol lock held, so we dont attempt to do this another time. Thanks to Andrew Morton for the beating:-) From: Brice Goglin <Brice.Goglin@ens-lyon.org> Build fix (akpm: this patch is still unpleasant. Ashok continues to look for a cleaner solution, doesn't he? ;)) Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Brice Goglin <Brice.Goglin@ens-lyon.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreqLinus Torvalds
2005-11-01[CPUFREQ] Fix up compile of cpufreq_statsDave Jones
Whoops, I lost a hunk of the last patch somehow. Signed-off-by: Dave Jones <davej@redhat.com>
2005-10-30[PATCH] create and destroy cpufreq sysfs entries based on cpu notifiersAshok Raj
cpufreq entries in sysfs should only be populated when CPU is online state. When we either boot with maxcpus=x and then boot the other cpus by echoing to sysfs online file, these entries should be created and destroyed when CPU_DEAD is notified. Same treatement as cache entries under sysfs. We place the processor in the lowest frequency, so hw managed P-State transitions can still work on the other threads to save power. Primary goal was to just make these directories appear/disapper dynamically. There is one in this patch i had to do, which i really dont like myself but probably best if someone handling the cpufreq infrastructure could give this code right treatment if this is not acceptable. I guess its probably good for the first cut. - Converting lock_cpu_hotplug()/unlock_cpu_hotplug() to disable/enable preempt. The locking was smack in the middle of the notification path, when the hotplug is already holding the lock. I tried another solution to avoid this so avoid taking locks if we know we are from notification path. The solution was getting very ugly and i decided this was probably good for this iteration until someone who understands cpufreq could do a better job than me. (akpm: export cpucontrol to GPL modules: drivers/cpufreq/cpufreq_stats.c now does lock_cpu_hotplug()) Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Zwane Mwaikambo <zwane@holomorphy.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30[PATCH] Remove cpu_sys_devices in cpufreq subsystem.Ashok Raj
cpu_sys_devices is redundant with the new API get_cpu_sysdev(). So nuking this usage since its not needed. Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Zwane Mwaikambo <zwane@holomorphy.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-27[PATCH] cpufreq: SMP fix for conservative governorDave Jones
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>
2005-10-27[CPUFREQ] Check return value of cpufreq_cpu_get in cpufreq_statsDave Jones
This fixes an issue found in drivers/cpufreq/cpufreq_stats.c by Coverity. Error reported: CID: 2642 Checker: NULL_RETURNS (help) File: /export2/p4-coverity/mc2/linux26/drivers/cpufreq/cpufreq_stats.c Function: cpufreq_stats_create_table Description: Dereferencing NULL value "data" Patch description: The return of cpufreq_cpu_get can be NULL, check return code and return -EINVAL if it is NULL. Signed-off-by: Jayachandran C. <c.jayachandran at gmail.com> Signed-off-by: Dave Jones <davej@redhat.com>
2005-10-20[CPUFREQ] kzalloc conversions for cpufreq core.Dave Jones
Signed-off-by: Dave Jones <davej@redhat.com>
2005-09-20[CPUFREQ] Avoid the ondemand cpufreq governor to use a too high frequency ↵Dave Jones
for stats. The problem is in the ondemand governor, there is a periodic measurement of the CPU usage. This CPU usage is updated by the scheduler after every tick (basically, by adding 1 either to "idle" or to "user" or to "system"). So if the frequency of the governor is too high, the stat will be meaningless (as mostly no number have changed). So this patch checks that the measurements are separated by at least 10 ticks. It means that by default, stats will have about 5% error (20 ticks). Of course those numbers can be argued but, IMHO, they look sane. The patch also includes a small clean-up to check more explictly the result of the conversion from ns to µs being null. Let's note that (on x86) this has never been really needed before 2.6.13 because HZ was always 1000. Now that HZ can be 100, some CPU might be affected by this problem. For instance when HZ=100, the centrino ,which has a 10µs transition latency, would lead to the governor allowing to read stats every tick (10ms)! Signed-off-by: Eric Piel <eric.piel@tremplin-utc.net> Signed-off-by: Dave Jones <davej@redhat.com>
2005-08-31[CPUFREQ] Bugfix: Call driver exit in cpufreq_add_dev error pathVenkatesh Pallipadi
A minor fix for cpufreq_add_dev() error path. We need to call driver->exit() if driver_init() call has succeeded. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
2005-07-28Here are two possible cleanups in cpufreq.c:Dave Jones
* ret has no need to be unsigned in cpufreq_driver_target() * ret has no need to be initialized in __cpufreq_governor() Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Dave Jones <davej@redhat.com>
2005-07-07[PATCH] pm: fix u32 vs. pm_message_t confusion in cpufreqBernard Blackham
Fix u32 vs pm_message_t confusion in cpufreq. Signed-off-by: Bernard Blackham <bernard@blackham.com.au> Signed-off-by: Pavel Machek <pavel@suse.cz> Cc: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-20[PATCH] sysfs: (rest) if show/store is missing return -EIODmitry Torokhov
sysfs: fix the rest of the kernel so if an attribute doesn't implement show or store method read/write will return -EIO instead of 0 or -EINVAL or -EPERM. Signed-off-by: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-31[PATCH] cpufreq-stats driver updatesVenkatesh Pallipadi
Changes to the cpufreq stats driver: * Changes the way P-state transition table looks in /sysfs providing more clear output * Changes the time unit in the output from HZ to clock_t Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-31[CPUFREQ] ondemand governor default sampling downfactor as 1Dave Jones
[PATCH] [5/5] ondemand governor default sampling downfactor as 1 Make default sampling downfactor 1. This works better with earlier auto downscaling change in ondemand governor. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-31[CPUFREQ] ondemand governor automatic downscalingDave Jones
[PATCH] [4/5] ondemand governor automatic downscaling Here is a change of policy for the ondemand governor. The modification concerns the frequency downscaling. Instead of decreasing to a lower frequency when the CPU usage is under 20%, this new policy automatically scales to the optimal frequency. The optimal frequency being the lowest frequency which provides enough power to not trigger the upscaling policy. 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>
2005-05-31[CPUFREQ] ondemand,conservative governor idle_tick clean-upDave Jones
[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>
2005-05-31[CPUFREQ] ondemand,conservative governor store the idle ticks for all cpusDave Jones
[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>
2005-05-31[CPUFREQ] ondemand,conservative minor bug-fix and cleanupDave Jones
[PATCH] [1/5] ondemand,conservative minor bug-fix and cleanup Attached patch fixes some minor issues with Alexander's patch and related cleanup in both ondemand and conservative governor. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-31[CPUFREQ] Allow ondemand stepping to be changed by user.Dave Jones
Adds support so that the cpufreq change stepping is no longer fixed at 5% and can be changed dynamically by the user Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-31[CPUFREQ] Prevents un-necessary cpufreq changes if we are already at min/maxDave Jones
Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-31[CPUFREQ] Add support to cpufreq_ondemand to ignore 'nice' cpu timeDave Jones
Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-31[CPUFREQ] Conservative cpufreq governerDave Jones
A new cpufreq module, based on the ondemand one with my additional patches just posted. This one is more suitable for battery environments where its probably more appealing to have the cpu freq gracefully increase and decrease rather than flip between the min and max freq's. N.B. Bruno Ducrot pointed out that the amd64's "do have unacceptable latency between min and max freq transition, due to the step-by-step requirements (200MHz IIRC)"; so AMD64 users would probably benefit from this too. Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-31[CPUFREQ] make cpufreq_gov_dbs staticDave Jones
This patch makes a needlessly global and EXPORT_SYMBOL'ed struct static. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-31[CPUFREQ] Add warning comment about default governors.Dave Jones
This comes up time and time again. Until its fixed, place this comment in the Kconfig which should stem the flow of resubmissions. Signed-off-by: Rob Weryk <rjweryk@uwo.ca> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-31[CPUFREQ] ondemand: trivial clean-upsDave Jones
Trivial ondemand governor clean-ups: - change from sampling_rate_in_HZ() to the official function usecs_to_jiffies(). - use for_each_online_cpu() to instead of using "if (cpu_online(i))" Signed-off-by: Eric Piel <eric.piel@tremplin-utc.net> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-31[CPUFREQ] cpufreq-core: reduce warning messages.Dave Jones
cpufreq core is printing out messages at KERN_WARNING level that the core recovers from without intervention, and that the system administrator can do nothing about. Patch below reduces the severity of these messages to debug. Signed-off-by: Matt Domsch <Matt_Domsch@dell.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Dave Jones <davej@redhat.com>
2005-05-02[PATCH] cpufreq annoying warning fixBenjamin Herrenschmidt
The cpufreq core patch I sent earlier got only half-applied. I added a flag to let the low level driver disable an annoying warning on suspend/resume that is normal on ppc, but the "resume" part of it wasn't applied. This just adds back that missing bit. The original patch also reworked the resume() function to avoid nesting too many if () statements along the way I did the suspend() one, but I didn't include that in the patch below. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-29[PATCH] Add suspend method to cpufreq coreBenjamin Herrenschmidt
In order to properly fix some issues with cpufreq vs. sleep on PowerBooks, I had to add a suspend callback to the pmac_cpufreq driver. I must force a switch to full speed before sleep and I switch back to previous speed on resume. I also added a driver flag to disable the warnings in suspend/resume since it is expected in this case to have different speed (and I want it to fixup the jiffies properly). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!