This more or less is a renaming and moving of functions and should not
introduce any functional change.

cpupower was built from cpufrequtils (which had a C library providing easy
access to cpu frequency platform info). In the meantime it got enhanced
by quite some neat cpuidle userspace tools.

Now the cpu idle functions have been separated and added to the cpupower.so
library.
So beside an already existing public header file:
cpufreq.h
cpupower now also exports these cpu idle functions in:
cpuidle.h

Here again pasted for better review of the interfaces:

======================================
int cpuidle_is_state_disabled(unsigned int cpu,
                                       unsigned int idlestate);
int cpuidle_state_disable(unsigned int cpu, unsigned int idlestate,
                                   unsigned int disable);
unsigned long cpuidle_state_latency(unsigned int cpu,
                                                unsigned int idlestate);
unsigned long cpuidle_state_usage(unsigned int cpu,
                                        unsigned int idlestate);
unsigned long long cpuidle_state_time(unsigned int cpu,
                                                unsigned int idlestate);
char *cpuidle_state_name(unsigned int cpu,
                                unsigned int idlestate);
char *cpuidle_state_desc(unsigned int cpu,
                                unsigned int idlestate);
unsigned int cpuidle_state_count(unsigned int cpu);

char *cpuidle_get_governor(void);
char *cpuidle_get_driver(void);

======================================
Signed-off-by: NThomas Renninger <trenn@suse.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

sysfs_get_idlestate_count() returns an unsigned int.  Returning -ENODEV
is not the right thing to do here, and in any case is handled the same
way as if there are no states found.
Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
Acked-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Link: https://bugzilla.kernel.org/show_bug.cgi?id=80621Reported-by: NDavid Binderman <dcb314@hotmail.com>
Signed-off-by: NAndrey Utkin <andrey.krieger.utkin@gmail.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

idlestates in sysfs are counted from 0.

This fixes a wrong error message.
Current behavior on a machine with 4 sleep states is:

cpupower idle-set -e 4
Idlestate 4 enabled on CPU 0

-----Wrong---------------------
cpupower idle-set -e 5
Idlestate enabling not supported by kernel
-----Must and now will be -----
cpupower idle-set -e 5
Idlestate 6 not available on CPU 0
-------------------------------

cpupower idle-set -e 6
Idlestate 6 not available on CPU 0
Signed-off-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Latest kernel allows to disable C-states via:
/sys/devices/system/cpu/cpuX/cpuidle/stateY/disable

This patch provides lower level sysfs access functions to make use of
this interface.  A later patch will implement the higher level stuff.
Signed-off-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Use unsigned int as the data type for some variables related to CPU
idle states which allows the code to be simplified slightly.

[rjw: Changelog]
Signed-off-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Fix minor warnings reported with GCC 4.6:
* The sysfs_write_file function is unused - remove it.
* The pr_mon_len in the print_header function is unsed - remove it.
Signed-off-by: NPalmer Cox <p@lmercox.com>
Signed-off-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

It's been broken forever (i.e. it's not scheduling in a power
aware fashion), as reported by Suresh and others sending
patches, and nobody cares enough to fix it properly ...
so remove it to make space free for something better.

There's various problems with the code as it stands today, first
and foremost the user interface which is bound to topology
levels and has multiple values per level. This results in a
state explosion which the administrator or distro needs to
master and almost nobody does.

Furthermore large configuration state spaces aren't good, it
means the thing doesn't just work right because it's either
under so many impossibe to meet constraints, or even if
there's an achievable state workloads have to be aware of
it precisely and can never meet it for dynamic workloads.

So pushing this kind of decision to user-space was a bad idea
even with a single knob - it's exponentially worse with knobs
on every node of the topology.

There is a proposal to replace the user interface with a single
3 state knob:

 sched_balance_policy := { performance, power, auto }

where 'auto' would be the preferred default which looks at things
like Battery/AC mode and possible cpufreq state or whatever the hw
exposes to show us power use expectations - but there's been no
progress on it in the past many months.

Aside from that, the actual implementation of the various knobs
is known to be broken. There have been sporadic attempts at
fixing things but these always stop short of reaching a mergable
state.

Therefore this wholesale removal with the hopes of spurring
people who care to come forward once again and work on a
coherent replacement.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1326104915.2442.53.camel@twinsSigned-off-by: NIngo Molnar <mingo@kernel.org>

Before, checking for offlined CPUs was done dirty and
it was checked whether topology parsing returned -1 values.
But this is a valid case on a Xen (and possibly other) kernels.

Do proper online/offline checking, also take CONFIG_HOTPLUG_CPU
option into account (no /sys/devices/../cpuX/online file).
Signed-off-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

CPU power consumption vs performance tuning is no longer
limited to CPU frequency switching anymore: deep sleep states,
traditional dynamic frequency scaling and hidden turbo/boost
frequencies are tied close together and depend on each other.
The first two exist on different architectures like PPC, Itanium and
ARM, the latter (so far) only on X86. On X86 the APU (CPU+GPU) will
only run most efficiently if CPU and GPU has proper power management
in place.

Users and Developers want to have *one* tool to get an overview what
their system supports and to monitor and debug CPU power management
in detail. The tool should compile and work on as many architectures
as possible.

Once this tool stabilizes a bit, it is intended to replace the
Intel-specific tools in tools/power/x86
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>