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152 commits

Author SHA1 Message Date
Stefano Brivio
232e8884cb [CPUFREQ] fix configuration help message
cpufreq support can't be built as a module. Fix the related configuration
help message.

Signed-off-by: Stefano Brivio <stefano.brivio@polimi.it>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-02-06 22:57:58 -05:00
Venki Pallipadi
9e76988e93 [CPUFREQ] Eliminate cpufreq_userspace scaling_setspeed deadlock
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 <unsupported> when governor is not userspace.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-02-06 22:57:58 -05:00
Fenghua Yu
e32d22f776 [CPUFREQ] fix incorrect comment on show_available_freqs() in freq_table.c
In freq_table.c, show_available_freqs()'s comment is oberviously wrong.
Change the comment to a new one to avoid confusion.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-02-06 22:57:58 -05:00
Joe Perches
a4a9df5825 [CPUFREQ] drivers/cpufreq: Add missing "space"
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-02-06 22:57:57 -05:00
Yi Yang
53391fa20c cpufreq: fix obvious condition statement error
The function __cpufreq_set_policy in file drivers/cpufreq/cpufreq.c
has a very obvious error:

        if (policy->min > data->min && policy->min > policy->max) {
                ret = -EINVAL;
                goto error_out;
        }

This condtion statement is wrong because it returns -EINVAL only if
policy->min is greater than policy->max (in this case,
"policy->min > data->min" is true for ever.). In fact, it should
return -EINVAL as well if policy->max is less than data->min.

The correct condition should be:

	if (policy->min > data->max || policy->max < data->min) {

The following test result testifies the above conclusion:

Before applying this patch:

[root@yangyi-dev /]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies
2394000 1596000
[root@yangyi-dev /]# echo 1596000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
[root@yangyi-dev /]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
1596000
[root@yangyi-dev /]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
1596000
[root@yangyi-dev /]# echo "2000000" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
-bash: echo: write error: Invalid argument
[root@yangyi-dev /]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
1596000
[root@yangyi-dev /]# echo "0" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
[root@yangyi-dev /]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
1596000
[root@yangyi-dev /]# echo "1595000" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
[root@yangyi-dev /]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
1596000
[root@yangyi-dev /]#

After applying this patch:

[root@yangyi-dev /]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies
2394000 1596000
[root@yangyi-dev /]# echo 1596000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
[root@yangyi-dev /]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
1596000
[root@yangyi-dev /]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
1596000
[root@localhost /]# echo "2000000" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
-bash: echo: write error: Invalid argument
[root@localhost /]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
1596000
[root@localhost /]# echo "0" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
-bash: echo: write error: Invalid argument
[root@localhost /]# echo "1595000" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
-bash: echo: write error: Invalid argument
[root@localhost /]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
1596000
[root@localhost /]# echo "1596000" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
[root@localhost /]# echo "2394000" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
[root@localhost /]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
2394000
[root@localhost /]

Signed-off-by: Yi Yang <yi.y.yang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:33:34 +01:00
Greg Kroah-Hartman
c10997f657 Kobject: convert drivers/* from kobject_unregister() to kobject_put()
There is no need for kobject_unregister() anymore, thanks to Kay's
kobject cleanup changes, so replace all instances of it with
kobject_put().


Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:40 -08:00
Greg Kroah-Hartman
038c5b3e41 Kobject: change drivers/cpufreq/cpufreq.c to use kobject_init_and_add
Stop using kobject_register, as this way we can control the sending of
the uevent properly, after everything is properly initialized.

Cc: Dominik Brodowski <linux@brodo.de>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Shin <jacob.shin@amd.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:28 -08:00
Johannes Weiner
6915719b36 cpufreq: Initialise default governor before use
When the cpufreq driver starts up at boot time, it calls into the default
governor which might not be initialised yet.  This hurts when the
governor's worker function relies on memory that is not yet set up by its
init function.

This migrates all governors from module_init() to fs_initcall() when being
the default, as was already done in cpufreq_performance when it was the
only possible choice.  The performance governor is always initialized early
because it might be used as fallback even when not being the default.

Fixes at least one actual oops where ondemand is the default governor and
cpufreq_governor_dbs() uses the uninitialised kondemand_wq work-queue
during boot-time.

Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-17 15:38:58 -08:00
Adrian Bunk
a33234735b drivers/cpufreq/cpufreq_stats.c section fix
cpufreq_stats_free_table() mustn't be __cpuexit since it's called by the
__cpuinit cpufreq_stat_cpu_callback().

This patch fixes the following section mismatch reported by
Chris Clayton:

WARNING: vmlinux.o(.init.text+0x143dd): Section mismatch: reference to .exit.text:cpufreq_stats_free_table (between 'cpufreq_stat_cpu_callback' and 'cpufreq_stats_init')

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Chris Clayton <chris2553@googlemail.com>
Acked-by: Dave Jones <davej@codemonkey.org.uk>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-17 19:28:16 -08:00
Dave Jones
bd6cba53c5 cpufreq: fix missing unlocks in cpufreq_add_dev error paths.
Ingo hit some BUG_ONs that were probably caused by these missing unlocks
causing an unbalance.  He couldn't reproduce the bug reliably, so it's
unknown that it's definitly fixing the problem he hit, but it's a fairly
good chance, and this fixes an obvious bug.

[ Dave: "Ingo followed up that he hit some lockdep related output with
         this applied, so it may not be right.  I'll look at it after
         xmas if no-one has it figured out before then."
  Akpm: "It looks pretty correct to me though." ]

Signed-off-by: Dave Jones <davej@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-17 19:28:16 -08:00
Dave Jones
18a7247d1b [CPUFREQ] Fix up whitespace in conservative governor.
Signed-off-by: Dave Jones <davej@redhat.com>
2007-10-22 16:49:09 -04:00
Elias Oltmanns
a8d7c3bc23 [CPUFREQ] Make cpufreq_conservative handle out-of-sync events properly
Make cpufreq_conservative handle out-of-sync events properly

Currently, the cpufreq_conservative governor doesn't get notified when the
actual frequency the cpu is running at differs from what cpufreq thought it
was. As a result the cpu may stay at the maximum frequency after a s2ram /
resume cycle even though the system is idle.

Signed-off-by: Elias Oltmanns <eo@nebensachen.de>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-10-22 16:34:39 -04:00
Linus Torvalds
efefc6eb38 Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: (75 commits)
  PM: merge device power-management source files
  sysfs: add copyrights
  kobject: update the copyrights
  kset: add some kerneldoc to help describe what these strange things are
  Driver core: rename ktype_edd and ktype_efivar
  Driver core: rename ktype_driver
  Driver core: rename ktype_device
  Driver core: rename ktype_class
  driver core: remove subsystem_init()
  sysfs: move sysfs file poll implementation to sysfs_open_dirent
  sysfs: implement sysfs_open_dirent
  sysfs: move sysfs_dirent->s_children into sysfs_dirent->s_dir
  sysfs: make sysfs_root a regular directory dirent
  sysfs: open code sysfs_attach_dentry()
  sysfs: make s_elem an anonymous union
  sysfs: make bin attr open get active reference of parent too
  sysfs: kill unnecessary NULL pointer check in sysfs_release()
  sysfs: kill unnecessary sysfs_get() in open paths
  sysfs: reposition sysfs_dirent->s_mode.
  sysfs: kill sysfs_update_file()
  ...
2007-10-12 15:49:37 -07:00
Greg Kroah-Hartman
19c38de88a kobjects: fix up improper use of the kobject name field
A number of different drivers incorrect access the kobject name field
directly.  This is not correct as the name might not be in the array.
Use the proper accessor function instead.
2007-10-12 14:51:02 -07:00
Andi Kleen
9eb59573d4 [CPUFREQ] Don't take semaphore in cpufreq_quick_get()
I don't see any reason to take an expensive lock in cpufreq_quick_get()
Reading policy->cur is a single atomic operation and after
the lock is dropped again the state could change any time anyways.

So don't take the lock in the first place.

This also makes this function interrupt safe which is useful
for some code of mine.

Signed-off-by: Andi Kleen <ak@suse.de>
Cc: "Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-10-09 21:44:06 -04:00
Satyam Sharma
55395ae72b [CPUFREQ] cpufreq_stats: misc cpuinit section annotations
* Stop referencing the callback directly from the __init and __exit
  functions of this driver, and instead explicitly call
  cpufreq_update_policy() et al. This enables the callback function
  to be marked as __cpuinit (and the notifier_block __cpuinitdata),
  thereby saving space when HOTPLUG_CPU=n. This also enables us to
  use other tricks to replace __cpuinit{data} in future.

* cpufreq_stats_free_table() is only called from __cpuinit or __exit
  marked functions, making it an ideal candidate for __cpuexit.

* Fix missing space in the module description

Signed-off-by: Satyam Sharma <satyam@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-10-04 18:40:57 -04:00
Satyam Sharma
dd184a01b8 [CPUFREQ] mark hotplug notifier callback as __cpuinit
The notifier_block is already __cpuinitdata, thereby allowing us to safely
mark the callback function as __cpuinit also, thereby saving space when
HOTPLUG_CPU=n.

Signed-off-by: Satyam Sharma <satyam@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-10-04 18:40:57 -04:00
Thomas Renninger
6afde10c3f [CPUFREQ] Only check for transition latency on problematic governors (kconfig fix)
Cc: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-10-04 18:40:57 -04:00
Thomas Renninger
1c2562459f [CPUFREQ] allow ondemand and conservative cpufreq governors to be used as default
Depending on the transition latency of the HW for cpufreq switches, the
ondemand or conservative governor cannot be used with certain cpufreq
drivers.  Still the ondemand should be the default governor on a wide range
of systems.  This patch allows this and lets the governor fallback to the
performance governor at cpufreq driver load time, if the driver does not
support fast enough frequency switching.

Main benefit is that on e.g.  installation or other systems without
userspace support a working dynamic cpufreq support can be achieved on most
systems by simply loading the cpufreq driver.  This is especially essential
for recent x86(_64) laptop hardware which may rely on working dynamic
cpufreq OS support.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Bryan Wu <bryan.wu@analog.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-10-04 18:40:57 -04:00
Thomas Renninger
8122c6cea0 [CPUFREQ] move policy's governor initialisation out of low-level drivers into cpufreq core
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Bryan Wu <bryan.wu@analog.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-10-04 18:40:57 -04:00
Thomas Renninger
084f349394 [CPUFREQ] Restore previously used governor on a hot-replugged CPU
Negative side effect: needs NR_CPUs pointer array of memory in
CONFIG_HOTPLUG_CPU case.

Still needs userspace track keeping and rewriting of governors if governors
change while a CPU is not active (always the governor at CPU remove time is
restored).

Move of policy->user_policy.governor assignment is just a minor cleanup.
http://bugzilla.kernel.org/show_bug.cgi?id=8671

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Mattia Dongili <malattia@linux.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-07-13 01:29:51 -04:00
Peter Oruba
91973de736 [CPUFREQ] bugfix cpufreq in combination with performance governor
There is a frequency scaling issue that I encountered with the performance
governor in combination with CPU hotplug.

In cpufreq.c CPU frequency is reduced to its minimum before the CPU gets
unregistered and set offline.  Does that have a particular reason?

Since the (k8-)governor does not monitor CPU frequency that setting also
applies then to the remaining CPU as well and lets the system run on the
lowest frequency although performance is chose as the policy.

Signed-off-by: Peter Oruba <peter.oruba@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-07-13 01:29:51 -04:00
Linus Torvalds
702ed6ef37 Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq
* 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.
2007-07-12 13:42:43 -07:00
Tejun Heo
7b595756ec sysfs: kill unnecessary attribute->owner
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 <htejun@gmail.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-11 16:09:06 -07:00
Tobias Klauser
58a7295bc8 [CPUFREQ] Fix sysfs_create_file return value handling
Commit 0a4b2ccc55 in cpufreq.git
eliminates the build warnings but does not pass on the error code of
sysfs_create_file to the function calling cpufreq_add_dev. Instead some
previous value of ret would be returned.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-06-21 12:57:54 -04:00
Venki Pallipadi
ea48761519 [CPUFREQ] ondemand: fix tickless accounting and software coordination bug
With tickless kernel and software coordination os P-states, ondemand
can look at wrong idle statistics. This can happen when ondemand sampling
is happening on CPU 0 and due to software coordination sampling also looks at
utilization of CPU 1. If CPU 1 is in tickless state at that moment, its idle
statistics will not be uptodate and CPU 0 thinks CPU 1 is idle for less
amount of time than it actually is.

This can be resolved by looking at all the busy times of CPUs, which is
accurate, even with tickless, and use that to determine idle time in a
round about way (total time - busy time).

Thanks to Arjan for originally reporting the ondemand bug on
Lenovo T61.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-06-21 12:57:53 -04:00
Venki Pallipadi
0af99b13c9 [CPUFREQ] ondemand: add a check to avoid negative load calculation
Due to rounding and inexact jiffy accounting, idle_ticks can sometimes
be higher than total_ticks. Make sure those cases are handled as
zero load case.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-06-21 12:57:53 -04:00
Venki Pallipadi
c7f652e048 [CPUFREQ] Keep userspace governor quiet when it is not being used
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 <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-06-21 12:57:53 -04:00
Thomas Renninger
0a4b2ccc55 [CPUFREQ] check return value of sysfs_create_file
Eliminate build warning (sysfs_create_file return value must be checked)

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-05-29 16:56:40 -04:00
Rafael J. Wysocki
8bb7844286 Add suspend-related notifications for CPU hotplug
Since nonboot CPUs are now disabled after tasks and devices have been
frozen and the CPU hotplug infrastructure is used for this purpose, we need
special CPU hotplug notifications that will help the CPU-hotplug-aware
subsystems distinguish normal CPU hotplug events from CPU hotplug events
related to a system-wide suspend or resume operation in progress.  This
patch introduces such notifications and causes them to be used during
suspend and resume transitions.  It also changes all of the
CPU-hotplug-aware subsystems to take these notifications into consideration
(for now they are handled in the same way as the corresponding "normal"
ones).

[oleg@tv-sign.ru: cleanups]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09 12:30:56 -07:00
Venki Pallipadi
28287033e1 Add a new deferrable delayed work init
Add a new deferrable delayed work init.  This can be used to schedule work
that are 'unimportant' when CPU is idle and can be called later, when CPU
eventually comes out of idle.

Use this init in cpufreq ondemand governor.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:05 -07:00
Mike Frysinger
9101be532a [CPUFREQ] cleanup kconfig options
Adds proper lines to help output of kconfig so people can find the module names.
Also fixed some broken leading spaces versus tabs.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-04-26 14:32:03 -04:00
Thomas Renninger
632786ce9f [CPUFREQ] Remove deprecated /proc/acpi/processor/performance write support
Remove deprecated /proc/acpi/processor/performance write support

Writing to /proc/acpi/processor/xy/performance interferes with sysfs
cpufreq interface. Also removes buggy cpufreq_set_policy exported symbol.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-04-26 14:32:02 -04:00
Thomas Renninger
22c970f346 [CPUFREQ] Fix limited cpufreq when booted on battery
References:
https://bugzilla.novell.com/show_bug.cgi?id=231107
https://bugzilla.novell.com/show_bug.cgi?id=264077

Fix limited cpufreq when booted on battery

If booted on battery:
cpufreq_set_policy (evil) is invoked which calls verify_within_limits.
max_freq gets lowered and therefore users_policy.max, which
is used to restore higher freqs via update_policy later is set to the
already limited frequency -> you can never go up again, even BIOS
allows higher freqs later.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-04-26 14:32:02 -04:00
Venki Pallipadi
ec28297a56 [PATCH] Fix maxcpus=1 trigerring BUG() in cpufreq
Ingo reported it on lkml in the thread
  "2.6.21-rc5: maxcpus=1 crash in cpufreq: kernel BUG at drivers/cpufreq/cpufreq.c:82!"

This check added to remove_dev  is symmetric to one in add_dev and handles
callbacks for offline cpus cleanly.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-27 08:55:56 -07:00
Linus Torvalds
221dee285e Revert "[CPUFREQ] constify cpufreq_driver where possible."
This reverts commit aeeddc1435, which was
half-baked and broken.  It just resulted in compile errors, since
cpufreq_register_driver() still changes the 'driver_data' by setting
bits in the flags field.  So claiming it is 'const' _really_ doesn't
work.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-26 14:55:48 -08:00
Linus Torvalds
6f8c480f99 Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq
* master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] constify some data tables.
  [CPUFREQ] constify cpufreq_driver where possible.
  {rd,wr}msr_on_cpu SMP=n optimization
  [CPUFREQ] cpufreq_ondemand.c: don't use _WORK_NAR
  rdmsr_on_cpu, wrmsr_on_cpu
  [CPUFREQ] Revert default on deprecated config X86_SPEEDSTEP_CENTRINO_ACPI
2007-02-26 14:17:50 -08:00
Dave Jones
aeeddc1435 [CPUFREQ] constify cpufreq_driver where possible.
Not all cases are possible due to ->flags being set at runtime
on some drivers.

Signed-off-by: Dave Jones <davej@redhat.com>
2007-02-22 19:08:27 -05:00
Oleg Nesterov
48ac3271e5 [CPUFREQ] cpufreq_ondemand.c: don't use _WORK_NAR
Looks like dbs_timer() is very careful wrt per_cpu(cpu_dbs_info),
and it doesn't need the help of WORK_STRUCT_NOAUTOREL.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-By: David Howells <dhowells@redhat.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-02-20 14:23:43 -05:00
Linus Torvalds
ef29498655 Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq
* master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] Longhaul - Redo Longhaul ver. 2
  [CPUFREQ] EPS - Correct 2nd brand test
  [CPUFREQ] Longhaul - Separate frequency and voltage transition
  [CPUFREQ] Longhaul - Models of Nehemiah
  [CPUFREQ] Whitespace fixup
  [CPUFREQ] Longhaul - Simplier minmult
  [CPUFREQ] CPU_FREQ_TABLE shouldn't be a def_tristate
  [CPUFREQ] ondemand governor use new cpufreq rwsem locking in work callback
  [CPUFREQ] ondemand governor restructure the work callback
  [CPUFREQ] Rewrite lock in cpufreq to eliminate cpufreq/hotplug related issues
  [CPUFREQ] Remove hotplug cpu crap
  [CPUFREQ] Enhanced PowerSaver driver
  [CPUFREQ] Longhaul - Add VT8235 support
  [CPUFREQ] Longhaul - Fix guess_fsb function
  [CPUFREQ] Longhaul - Remove duplicate tables
  [CPUFREQ] Longhaul - Introduce Nehemiah C
  [CPUFREQ] fix cpuinfo_cur_freq for CPU_HW_PSTATE
  [CPUFREQ] Longhaul - Remove "ignore_latency" option
2007-02-16 08:16:01 -08:00
Tim Schmielau
cd354f1ae7 [PATCH] remove many unneeded #includes of sched.h
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there.  Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.

To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.

Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm.  I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).

Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-14 08:09:54 -08:00
Dave Jones
c18a1483f4 [CPUFREQ] Whitespace fixup
Signed-off-by: Dave Jones <davej@redhat.com>
2007-02-10 20:03:51 -05:00
Adrian Bunk
f0ec313a89 [CPUFREQ] CPU_FREQ_TABLE shouldn't be a def_tristate
CPU_FREQ_TABLE enables helper code and gets select'ed when it's required.

Building it as a module when it's not required doesn't seem to make much sense.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-02-10 20:01:48 -05:00
Venkatesh Pallipadi
56463b78cd [CPUFREQ] ondemand governor use new cpufreq rwsem locking in work callback
Eliminate flush_workqueue in cpufreq_governor(STOP) callpath. Using flush
there has a deadlock potential as in

http://uwsg.iu.edu/hypermail/linux/kernel/0611.3/1223.html

Also, cleanup the locking issues with do_dbs_timer delayed_work callback.  As
it changes the CPU frequency using __cpufreq_target, it needs to have
policy_rwsem in write mode, which also protects it from hot plug.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-02-10 20:01:48 -05:00
Venkatesh Pallipadi
529af7a14f [CPUFREQ] ondemand governor restructure the work callback
Restructure the delayed_work callback in ondemand.

This eliminates the need for smp_processor_id in the callback function and
also helps in proper locking and avoiding flush_workqueue when stopping the
governor (done in subsequent patch).

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-02-10 20:01:47 -05:00
Venkatesh Pallipadi
5a01f2e8f3 [CPUFREQ] Rewrite lock in cpufreq to eliminate cpufreq/hotplug related issues
Yet another attempt to resolve cpufreq and hotplug locking issues.

Patchset has 3 patches:
* Rewrite the lock infrastructure of cpufreq using a per cpu rwsem.
* Minor restructuring of work callback in ondemand driver.
* Use the new cpufreq rwsem infrastructure in ondemand work.

This patch:

Convert policy->lock to rwsem and move it to per_cpu area.
This rwsem will protect against both changing/accessing policy
related parameters and CPU hot plug/unplug.

[malattia@linux.it: fix oops in kref_put()]
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Mattia Dongili <malattia@linux.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-02-10 20:01:47 -05:00
Dave Jones
c120069779 [CPUFREQ] Remove hotplug cpu crap
The hotplug CPU locking in cpufreq is horrendous.  No-one seems to care
enough to fix it, so just remove it so that the 99.9% of the real world
users of this code can use cpufreq without being bothered by warnings.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-02-10 20:01:47 -05:00
Ahmed S. Darwish
0142f9dce8 [CPUFREQ] check sysfs_create_link return value
Trivial patch to check sysfs_create_link return values.
Fail gracefully if needed.

Signed-off-by: Ahmed Darwish <darwish.07@gmail.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-01-29 00:06:27 -05:00
Venkatesh Pallipadi
8edc59d939 [CPUFREQ] Bug fix for acpi-cpufreq and cpufreq_stats oops on frequency change notification
Fixes the oops in cpufreq_stats with acpi_cpufreq driver.  The issue was
that the frequency was reported as 0 in acpi-cpufreq.c.  The bug is due to
different indicies for freq_table and ACPI perf table.

Also adds a check in cpufreq_stats to check for error return from
freq_table_get_index() and avoid using the error return value.

Patch fixes the issue reported at
http://www.ussg.iu.edu/hypermail/linux/kernel/0611.2/0629.html
and also other similar issue here
http://bugme.osdl.org/show_bug.cgi?id=7383 comment 53

Signed-off-by: Dhaval Giani <dhaval.giani@gmail.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2006-12-22 22:45:41 -05:00
Dhaval Giani
4ab70df451 [CPUFREQ] fixes typo in cpufreq.c
This patch fixes a typo in cpufreq.c

From: Dhaval Giani <dhaval.giani@gmail.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2006-12-13 10:11:25 -05:00