Commit Graph

257 Commits

Author SHA1 Message Date
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
Dave Jones 905d77cd95 [CPUFREQ] more CodingStyle
void * p   ->  void *p
no space between function parameters
removed excess whitespace

Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
2008-04-28 15:05:42 -04:00
Dave Jones 4d34a67d02 [CPUFREQ] CodingStyle
return is not a function.

Signed-off-by: Dave Jones <davej@redhat.com>
2008-04-28 15:05:41 -04:00
Dave Jones c906049447 [CPUFREQ] Slightly shorten the error paths of cpufreq_suspend/cpufreq_resume
Signed-off-by: Dave Jones <davej@redhat.com>
2008-04-28 15:05:41 -04:00
Sam Ravnborg f6ebef30e2 [CPUFREQ] fix section mismatch warnings
Fix the following warnings:
WARNING: vmlinux.o(.text+0xfe6711): Section mismatch in reference from the function cpufreq_unregister_driver() to the variable .cpuinit.data:cpufreq_cpu_notifier
WARNING: vmlinux.o(.text+0xfe68af): Section mismatch in reference from the function cpufreq_register_driver() to the variable .cpuinit.data:cpufreq_cpu_notifier
WARNING: vmlinux.o(.exit.text+0xc4fa): Section mismatch in reference from the function cpufreq_stats_exit() to the variable .cpuinit.data:cpufreq_stat_cpu_notifier

The warnings were casued by references to unregister_hotcpu_notifier()
from normal functions or exit functions.
This is flagged by modpost as a potential error because
it does not know that for the non HOTPLUG_CPU
scenario the unregister_hotcpu_notifier() is a nop.
Silence the warning by replacing the __initdata
annotation with a __refdata annotation.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
2008-03-05 14:45:31 -05:00
Dave Jones a07530b445 [CPUFREQ] Fix missing cpufreq_cpu_put() call in ->store
refactor to use gotos instead of explicit exit paths

Signed-off-by: Dave Jones <davej@redhat.com>
2008-03-05 14:45:31 -05:00
Dave Jones 0db4a8a99f [CPUFREQ] Fix missing cpufreq_cpu_put() call in ->show
refactor to use gotos instead of explicit exit paths

Signed-off-by: Dave Jones <davej@redhat.com>
2008-03-05 14:45:31 -05:00
Balaji Rao 7ab4705045 cpufreq: fix kobject reference count handling
The cpufreq core should not take an extra kobject reference count for no
reason, and then refuse to release it.  This has been reported as
keeping machines from properly powering down all the way.


Signed-off-by: Balaji Rao <balajirrao@gmail.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Yi Yang <yi.y.yang@intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Frans Pop <elendil@planet.nl>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-21 15:27:06 -08:00
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