Commit Graph

209 Commits

Author SHA1 Message Date
Linus Torvalds ada19a31a9 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq: (35 commits)
  [CPUFREQ] Prevent p4-clockmod from auto-binding to the ondemand governor.
  [CPUFREQ] Make cpufreq-nforce2 less obnoxious
  [CPUFREQ] p4-clockmod reports wrong frequency.
  [CPUFREQ] powernow-k8: Use a common exit path.
  [CPUFREQ] Change link order of x86 cpufreq modules
  [CPUFREQ] conservative: remove 10x from def_sampling_rate
  [CPUFREQ] conservative: fixup governor to function more like ondemand logic
  [CPUFREQ] conservative: fix dbs_cpufreq_notifier so freq is not locked
  [CPUFREQ] conservative: amend author's email address
  [CPUFREQ] Use swap() in longhaul.c
  [CPUFREQ] checkpatch cleanups for acpi-cpufreq
  [CPUFREQ] powernow-k8: Only print error message once, not per core.
  [CPUFREQ] ondemand/conservative: sanitize sampling_rate restrictions
  [CPUFREQ] ondemand/conservative: deprecate sampling_rate{min,max}
  [CPUFREQ] powernow-k8: Always compile powernow-k8 driver with ACPI support
  [CPUFREQ] Introduce /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_transition_latency
  [CPUFREQ] checkpatch cleanups for powernow-k8
  [CPUFREQ] checkpatch cleanups for ondemand governor.
  [CPUFREQ] checkpatch cleanups for powernow-k7
  [CPUFREQ] checkpatch cleanups for speedstep related drivers.
  ...
2009-03-26 11:04:08 -07:00
Dave Jones 129f8ae9b1 Revert "[CPUFREQ] Disable sysfs ui for p4-clockmod."
This reverts commit e088e4c9cd.

Removing the sysfs interface for p4-clockmod was flagged as a
regression in bug 12826.

Course of action:
 - Find out the remaining causes of overheating, and fix them
   if possible. ACPI should be doing the right thing automatically.
   If it isn't, we need to fix that.
 - mark p4-clockmod ui as deprecated
 - try again with the removal in six months.

It's not really feasible to printk about the deprecation, because
it needs to happen at all the sysfs entry points, which means adding
a lot of strcmp("p4-clockmod".. calls to the core, which.. bleuch.

Signed-off-by: Dave Jones <davej@redhat.com>
2009-03-09 15:07:33 -04:00
Alexander Clouter a75603a084 [CPUFREQ] conservative: remove 10x from def_sampling_rate
AMD users get particular hit by this issue (bug 8081) as it caps at
typically 90 seconds as the minimum period for a frequency change.
Harsh eh?  Years ago I borked this buy puting the 10x in the wrong
place...I fix that by removing it altogether.

Signed-off-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:32 -05:00
Alexander Clouter 8e677ce83b [CPUFREQ] conservative: fixup governor to function more like ondemand logic
As conservative is based off ondemand the codebases occasionally need to be
resync'd.  This patch, although ugly, does this.

Signed-off-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:32 -05:00
Alexander Clouter f407a08bb7 [CPUFREQ] conservative: fix dbs_cpufreq_notifier so freq is not locked
When someone added the dbs_cpufreq_notifier section to the governor the
code ended up causing the frequency to only fall.  This is because
requested_freq is tinkered with and that should only modified if it has
an invlaid value due to changes in the available frequency ranges

This should fix #10055.

Signed-off-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:32 -05:00
Alexander Clouter 11a80a9c76 [CPUFREQ] conservative: amend author's email address
Amend author's email address.

Signed-off-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:31 -05:00
Thomas Renninger 112124ab0a [CPUFREQ] ondemand/conservative: sanitize sampling_rate restrictions
Limit sampling rate to transition_latency * 100 or kernel limits.
If sampling_rate is tried to be set too low, set the lowest allowed value.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:31 -05:00
Thomas Renninger 9411b4ef7f [CPUFREQ] ondemand/conservative: deprecate sampling_rate{min,max}
The same info can be obtained via the transition_latency sysfs file

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:31 -05:00
Thomas Renninger ed12978453 [CPUFREQ] Introduce /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_transition_latency
It's not only useful for the ondemand and conservative governors, but
also for userspace daemons to know about the HW transition latency of
the CPU.
It is especially useful for userspace to know about this value when
the ondemand or conservative governors are run. The sampling rate
control value depends on it and for userspace being able to set sane
tuning values there it has to know about the transition latency.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:31 -05:00
Dave Jones 2b03f891ad [CPUFREQ] checkpatch cleanups for ondemand governor.
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:30 -05:00
Dave Jones 97acec55de [CPUFREQ] checkpatch cleanups for freq_table
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:30 -05:00
Dave Jones 1bceb8d139 [CPUFREQ] checkpatch cleanups for userspace governor
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:30 -05:00
Dave Jones 0a829c5afd [CPUFREQ] checkpatch cleanups for cpufreq_stats
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:30 -05:00
Dave Jones 9acef48756 [CPUFREQ] checkpatch cleanups for conservative governor
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:29 -05:00
Dave Jones 29464f2813 [CPUFREQ] checkpatch cleanups for cpufreq core
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:29 -05:00
Venkatesh Pallipadi 1ca3abdb6a [CPUFREQ] Make ignore_nice_load setting of ondemand work as expected.
ondemand micro-accounting of idle time changes broke ignore_nice_load
sysfs setting due to a thinko in the code.

The bug entry:
http://bugzilla.kernel.org/show_bug.cgi?id=12310

Reported-by: Jim Bray <jimsantelmo@gmail.com>

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-05 12:25:26 -05:00
Linus Torvalds 4e9b1c184c Merge branch 'cpus4096-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'cpus4096-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  [IA64] fix typo in cpumask_of_pcibus()
  x86: fix x86_32 builds for summit and es7000 arch's
  cpumask: use work_on_cpu in acpi-cpufreq.c for read_measured_perf_ctrs
  cpumask: use work_on_cpu in acpi-cpufreq.c for drv_read and drv_write
  cpumask: use cpumask_var_t in acpi-cpufreq.c
  cpumask: use work_on_cpu in acpi/cstate.c
  cpumask: convert struct cpufreq_policy to cpumask_var_t
  cpumask: replace CPUMASK_ALLOC etc with cpumask_var_t
  x86: cleanup remaining cpumask_t ops in smpboot code
  cpumask: update pci_bus_show_cpuaffinity to use new cpumask API
  cpumask: update local_cpus_show to use new cpumask API
  ia64: cpumask fix for is_affinity_mask_valid()
2009-01-10 06:12:18 -08:00
Frederik Schwarzer 0211a9c850 trivial: fix an -> a typos in documentation and comments
It is always "an" if there is a vowel _spoken_ (not written).
So it is:
"an hour" (spoken vowel)
but
"a uniform" (spoken 'j')

Signed-off-by: Frederik Schwarzer <schwarzerf@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-01-06 11:28:07 +01:00
Rusty Russell 835481d9bc cpumask: convert struct cpufreq_policy to cpumask_var_t
Impact: use new cpumask API to reduce memory usage

This is part of an effort to reduce structure sizes for machines
configured with large NR_CPUS.  cpumask_t gets replaced by
cpumask_var_t, which is either struct cpumask[1] (small NR_CPUS) or
struct cpumask * (large NR_CPUS).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Dave Jones <davej@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-06 09:05:31 +01:00
Mike Chan 187d9f4ed4 [CPUFREQ] Fix on resume, now preserves user policy min/max.
Previously driver resume would always set the current policy min/max with
the cpuinfo min/max, defined by user_policy.min/max. Resulting in a reset
of policy settings when policy.min/max != cpuinfo.min/max when coming out
of suspend. Now user_policy is saved as the policy instead of cpuinfo to
preserve what the user actually set.

Signed-off-by: Mike Chan <mike@android.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-12-05 15:20:11 -05:00
Matthew Garrett e088e4c9cd [CPUFREQ] Disable sysfs ui for p4-clockmod.
p4-clockmod has a long history of abuse.   It pretends to be a CPU
frequency scaling driver, even though it doesn't actually change
the CPU frequency, but instead just modulates the frequency with
wait-states.
The biggest misconception is that when running at the lower 'frequency'
p4-clockmod is saving power.  This isn't the case, as workloads running
slower take longer to complete, preventing the CPU from entering deep C states.

However p4-clockmod does have a purpose.  It can prevent overheating.
Having it hooked up to the cpufreq interfaces is the wrong way to achieve
cooling however. It should instead be hooked up to ACPI.

This diff introduces a means for a cpufreq driver to register with the
cpufreq core, but not present a sysfs interface.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-12-05 15:20:10 -05:00
Andrea Righi 4f6e6b9f97 [CPUFREQ] Fix BUG: using smp_processor_id() in preemptible code
Use get_cpu()/put_cpu() in cpufreq_ondemand init routine, instead of
smp_processor_id() to avoid the following BUG:

[   35.313118] BUG: using smp_processor_id() in preemptible [00000000] code=: modprobe/4952
[   35.313132] caller is cpufreq_gov_dbs_init+0xa/0x8f [cpufreq_ondemand]
[   35.313140] Pid: 4952, comm: modprobe Not tainted 2.6.27-rc5-mm1 #23
[   35.313145] Call Trace:
[   35.313158]  [<ffffffff80361ff7>] debug_smp_processor_id+0xd7/0xe0
[   35.313167]  [<ffffffffa010800a>] cpufreq_gov_dbs_init+0xa/0x8f [cpufreq_ondemand]
[   35.313176]  [<ffffffff8020903b>] _stext+0x3b/0x160
[   35.313185]  [<ffffffff804768c5>] __mutex_unlock_slowpath+0xe5/0x190
[   35.313195]  [<ffffffff8026236a>] trace_hardirqs_on_caller+0xca/0x140
[   35.313205]  [<ffffffff8026ef4c>] sys_init_module+0xdc/0x210
[   35.313212]  [<ffffffff8020b7cb>] system_call_fastpath+0x16/0x1b

Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-10-09 13:52:44 -04:00
Sven Wegener c4d14bc0bb [CPUFREQ] Don't export governors for default governor
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 <sven.wegener@stealer.net>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-10-09 13:52:44 -04:00
venkatesh.pallipadi@intel.com 8080091310 [CPUFREQ][6/6] cpufreq: Add idle microaccounting in ondemand governor
Use get_cpu_idle_time_us() to get micro-accounted idle information.
This enables ondemand to get more accurate idle and busy timings
than the jiffy based calculation. As a result, we can decrease
the ondemand safety gaurd band from 80-10 to 95-3.

Results in more aggressive power savings.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-10-09 13:52:44 -04:00
venkatesh.pallipadi@intel.com e9d95bf7eb [CPUFREQ][4/6] cpufreq_ondemand: Parameterize down differential
Use a parameter for down differential, instead of hardcoded 10%. Follow-on
patch changes the down-differential dynamically, based on whether
we are using idle micro-accounting or not.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-10-09 13:52:44 -04:00
venkatesh.pallipadi@intel.com 3430502d35 [CPUFREQ][3/6] cpufreq: get_cpu_idle_time() changes in ondemand for idle-microaccounting
Preparatory changes for doing idle micro-accounting in ondemand governor.
get_cpu_idle_time() gets extra parameter and returns idle time and also the
wall time that corresponds to the idle time measurement.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-10-09 13:52:44 -04:00
venkatesh.pallipadi@intel.com c43aa3bd99 [CPUFREQ][2/6] cpufreq: Change load calculation in ondemand for software coordination
Change the load calculation algorithm in ondemand to work well with software
coordination of frequency across the dependent cpus.

Multiply individual CPU utilization with the average freq of that logical CPU
during the measurement interval (using getavg call). And find the max CPU
utilization number in terms of CPU freq. That number is then used to
get to the target freq for next sampling interval.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-10-09 13:52:43 -04:00
venkatesh.pallipadi@intel.com bf0b90e357 [CPUFREQ][1/6] cpufreq: Add cpu number parameter to __cpufreq_driver_getavg()
Add a cpu parameter to __cpufreq_driver_getavg(). This is needed for software
cpufreq coordination where policy->cpu may not be same as the CPU on which we
want to getavg frequency.

A follow-on patch will use this parameter to getavg freq from all cpus
in policy->cpus.

Change since last patch. Fix the offline/online and suspend/resume
oops reported by Youquan Song <youquan.song@intel.com>

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-10-09 13:52:43 -04:00
Ben Slusky 8217e4f4c9 [CPUFREQ] use deferrable delayed work init in conservative governor
Venki Pallipadi made a similar change to the ondemand governor a while
back (in commit 28287033e1). It seems to
work just as well in the conservative governor, leading to fewer wakeups
as reported by powertop.

Signed-off-by: Ben Slusky <sluskyb@paranoiacs.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-10-09 13:52:43 -04:00
Julia Lawall f1829e4a37 [CPUFREQ] drivers/cpufreq/cpufreq.c: Adjust error handling code involving cpufreq_cpu_put
After calling cpufreq_cpu_get, error handling code should call
cpufreq_cpu_put.

The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r@
expression x,E;
statement S;
position p1,p2,p3;
@@

(
if ((x = cpufreq_cpu_get@p1(...)) == NULL || ...) S
|
x = cpufreq_cpu_get@p1(...)
... when != x
if (x == NULL || ...) S
)
<...
if@p3 (...) { ... when != cpufreq_cpu_put(x)
                  when != if (x) { ... cpufreq_cpu_put(x); ...}
    return@p2 ...;
}
...>
(
return x;
|
return 0;
|
x = E
|
E = x
|
cpufreq_cpu_put(x)
)

@exists@
position r.p1,r.p2,r.p3;
expression x;
int ret != 0;
statement S;
@@

* x = cpufreq_cpu_get@p1(...)
  <...
* if@p3 (...)
  S
  ...>
* return@p2 \(NULL\|ret\);
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-10-09 13:52:43 -04:00
Akinobu Mita 888a794cac [CPUFREQ] add error handling for cpufreq_register_governor() error
Add error handling for cpufreq_register_governor() error

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: cpufreq@lists.linux.org.uk
Signed-off-by: Dave Jones <davej@redhat.com>
2008-10-09 13:52:43 -04:00
Dave Jones f068c04ba6 [CPUFREQ] Fix -Wshadow warning in conservative governor.
drivers/cpufreq/cpufreq_conservative.c:336:15: warning: symbol 'freq_step' shadows an earlier one

Just rename the local variable.

Signed-off-by: Dave Jones <davej@redhat.com>
2008-08-08 16:00:48 -04:00
Thomas Renninger a1531acd43 cpufreq acpi: only call _PPC after cpufreq ACPI init funcs got called already
Ingo Molnar provided a fix to not call _PPC at processor driver
initialization time in "[PATCH] ACPI: fix cpufreq regression" (git
commit e4233dec74)

But it can still happen that _PPC is called at processor driver
initialization time.

This patch should make sure that this is not possible anymore.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-30 09:41:43 -07:00
Linus Torvalds 26dcce0fab Merge branch 'cpus4096-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'cpus4096-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (31 commits)
  NR_CPUS: Replace NR_CPUS in speedstep-centrino.c
  cpumask: Provide a generic set of CPUMASK_ALLOC macros, FIXUP
  NR_CPUS: Replace NR_CPUS in cpufreq userspace routines
  NR_CPUS: Replace per_cpu(..., smp_processor_id()) with __get_cpu_var
  NR_CPUS: Replace NR_CPUS in arch/x86/kernel/genapic_flat_64.c
  NR_CPUS: Replace NR_CPUS in arch/x86/kernel/genx2apic_uv_x.c
  NR_CPUS: Replace NR_CPUS in arch/x86/kernel/cpu/proc.c
  NR_CPUS: Replace NR_CPUS in arch/x86/kernel/cpu/mcheck/mce_64.c
  cpumask: Optimize cpumask_of_cpu in lib/smp_processor_id.c, fix
  cpumask: Use optimized CPUMASK_ALLOC macros in the centrino_target
  cpumask: Provide a generic set of CPUMASK_ALLOC macros
  cpumask: Optimize cpumask_of_cpu in lib/smp_processor_id.c
  cpumask: Optimize cpumask_of_cpu in kernel/time/tick-common.c
  cpumask: Optimize cpumask_of_cpu in drivers/misc/sgi-xp/xpc_main.c
  cpumask: Optimize cpumask_of_cpu in arch/x86/kernel/ldt.c
  cpumask: Optimize cpumask_of_cpu in arch/x86/kernel/io_apic_64.c
  cpumask: Replace cpumask_of_cpu with cpumask_of_cpu_ptr
  Revert "cpumask: introduce new APIs"
  cpumask: make for_each_cpu_mask a bit smaller
  net: Pass reference to cpumask variable in net/sunrpc/svc.c
  ...

Fix up trivial conflicts in drivers/cpufreq/cpufreq.c manually
2008-07-23 18:37:44 -07:00
Linus Torvalds 6d52dcbe56 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] cpufreq: remove CVS keywords
  [CPUFREQ] change cpu freq arrays to per_cpu variables
2008-07-21 15:10:37 -07:00
Mike Travis b38868aabe NR_CPUS: Replace NR_CPUS in cpufreq userspace routines
* 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 <travis () sgi ! com>
    Date:       2008-02-08 23:37:39

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-20 10:21:11 +02:00
Ingo Molnar 68083e05d7 Merge commit 'v2.6.26-rc9' into cpus4096 2008-07-06 14:23:39 +02:00
Linus Torvalds cc55875e26 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] Fix format string bug.
2008-06-09 11:27:55 -07:00
Chris Wright 326f6a5c9c [CPUFREQ] Fix format string bug.
Format string bug.  Not exploitable, as this is only writable by root,
but worth fixing all the same.

Spotted-by: Ilja van Sprundel <ilja@netric.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-06-09 13:24:55 -04:00
CHIKAMA masaki 879000f944 cpufreq: fix null object access on Transmeta CPU
If cpu specific cpufreq driver(i.e.  longrun) has "setpolicy" function,
governor object isn't set into cpufreq_policy object at "__cpufreq_set_policy"
function in driver/cpufreq/cpufreq.c .

This causes a null object access at "store_scaling_setspeed" and
"show_scaling_setspeed" function in driver/cpufreq/cpufreq.c when reading or
writing through /sys interface (ex.  cat
/sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed)

Addresses:
	http://bugzilla.kernel.org/show_bug.cgi?id=10654
	https://bugzilla.redhat.com/show_bug.cgi?id=443354

Signed-off-by: CHIKAMA Masaki <masaki.chikama@gmail.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Chuck Ebbert <cebbert@redhat.com>
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-06-06 11:29:11 -07:00
Lothar Waßmann dca0261393 [CPUFREQ] fix double unlock of cpu_policy_rwsem in drivers/cpufreq/cpufreq.c
In drivers/cpufreq/cpufreq.c the function cpufreq_add_dev() takes the
error exit 'err_out_unregister' from different places once with the
'cpu_policy_rwsem' lock held, once with the lock released:
|		if (ret)
|			goto err_out_unregister;
|	}
|
|	policy->governor = NULL; /* to assure that the starting sequence is
|				  * run in cpufreq_set_policy */
|
|	/* set default policy */
|	ret = __cpufreq_set_policy(policy, &new_policy);
|	policy->user_policy.policy = policy->policy;
|	policy->user_policy.governor = policy->governor;
|
|	unlock_policy_rwsem_write(cpu);
|
|	if (ret) {
|		dprintk("setting policy failed\n");
|		goto err_out_unregister;
|	}

This leads to the following error message in case of a failing
__cpufreq_set_policy() call:
=====================================
[ BUG: bad unlock balance detected! ]
-------------------------------------
swapper/1 is trying to release lock (&per_cpu(cpu_policy_rwsem, cpu)) at:
[<c01b4564>] unlock_policy_rwsem_write+0x30/0x40
but there are no more locks to release!

other info that might help us debug this:
1 lock held by swapper/1:
 #0:  (sysdev_drivers_lock){--..}, at: [<c018fd18>] sysdev_driver_register+0x74/0x130

stack backtrace:
[<c002f588>] (dump_stack+0x0/0x14) from [<c00692fc>] (print_unlock_inbalance_bug+0xc8/0x104)
[<c0069234>] (print_unlock_inbalance_bug+0x0/0x104) from [<c006b7ac>] (lock_release_non_nested+0xc4/0x19c)
 r6:00000028 r5:c3c1ab80 r4:c01b4564
[<c006b6e8>] (lock_release_non_nested+0x0/0x19c) from [<c006b9e0>] (lock_release+0x15c/0x18c)
 r8:60000013 r7:00000001 r6:c01b4564 r5:c0541bb4 r4:c3c1ab80
[<c006b884>] (lock_release+0x0/0x18c) from [<c0061ba0>] (up_write+0x24/0x30)
 r8:c0541b80 r7:00000000 r6:ffffffea r5:c3c34828 r4:c0541b8c
[<c0061b7c>] (up_write+0x0/0x30) from [<c01b4564>] (unlock_policy_rwsem_write+0x30/0x40)
 r4:c3c34884
[<c01b4534>] (unlock_policy_rwsem_write+0x0/0x40) from [<c01b4c40>] (cpufreq_add_dev+0x324/0x398)
[<c01b491c>] (cpufreq_add_dev+0x0/0x398) from [<c018fd64>] (sysdev_driver_register+0xc0/0x130)
[<c018fca4>] (sysdev_driver_register+0x0/0x130) from [<c01b3574>] (cpufreq_register_driver+0xbc/0x174)

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-05-29 12:10:12 -04:00
Mike Travis 068b12772a cpufreq: use performance variant for_each_cpu_mask_nr
Change references from for_each_cpu_mask to for_each_cpu_mask_nr
where appropriate

Reviewed-by: Paul Jackson <pj@sgi.com>
Reviewed-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 18:35:12 +02:00
Dominik Brodowski 4f74369422 [CPUFREQ] clarify license of freq_table.c
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-05-22 16:38:03 -04:00
Mike Travis 7a6aedfac9 [CPUFREQ] change cpu freq arrays to per_cpu variables
Change cpufreq_policy and cpufreq_governor pointer tables
from arrays to per_cpu variables in the cpufreq subsystem.

Also some minor complaints from checkpatch.pl fixed.

Based on:
	git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
	git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86.git

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-05-19 18:17:49 -04:00
Shaohua Li 6501faf8c1 [CPUFREQ] state info wrong after resume
Sometimes old_index != stat->last_index, see cpufreq_update_policy, bios can
change cpu setting in resume.  In my test, after resume cpu is in lowest
speed, but the stat info shows cpu is in full speed.  This patch makes the
stat info correct after a resume.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-04-28 16:27:08 -04:00
Alessandro Guido 30d221db44 [CPUFREQ] allow use of the powersave governor as the default one
Allow use of the powersave cpufreq governor as the default one for EMBEDDED
configs.

Signed-off-by: Alessandro Guido <alessandro.guido@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-04-28 16:27:08 -04:00
Darrick J. Wong e8628dd06d [CPUFREQ] expose cpufreq coordination requirements regardless of coordination mechanism
Currently, affected_cpus shows which CPUs need to have their frequency
coordinated in software.  When hardware coordination is in use, the contents
of this file appear the same as when no coordination is required.  This can
lead to some confusion among user-space programs, for example, that do not
know that extra coordination is required to force a CPU core to a particular
speed to control power consumption.

To fix this, create a "related_cpus" attribute that always displays the
coordination map regardless of whatever coordination strategy the cpufreq
driver uses (sw or hw).  If the cpufreq driver does not provide a value, fall
back to policy->cpus.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-04-28 16:27:08 -04:00
Cesar Eduardo Barros 25aca347d4 [CPUFREQ] fix show_trans_table
Fix show_trans_table when it overflows PAGE_SIZE.

* Not all snprintf calls were protected against being passed a negative
length.
* When show_trans_table overflows, len might be > PAGE_SIZE. In that case,
returns PAGE_SIZE.

Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net>
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
2008-04-28 15:05:44 -04:00
Cesar Eduardo Barros 74212ca432 [CPUFREQ] Warn when cpufreq_register_notifier called before pure initcalls
If cpufreq_register_notifier is called before pure initcalls,
init_cpufreq_transition_notifier_list will overwrite whatever it did,
causing notifiers to be ignored.

Print some noise to the kernel log if that happens.

Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net>
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
2008-04-28 15:05:44 -04:00
Dave Jones 4570911811 [CPUFREQ] Refactor locking in cpufreq_add_dev
Simplify this by moving the unlocking out of the error
paths into the exit path.

Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
2008-04-28 15:05:42 -04:00