History log of /linux-master/tools/power/cpupower/utils/helpers/sysfs.c
Revision Date Author Comments
# 4f19048f 27-May-2019 Thomas Gleixner <tglx@linutronix.de>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166

Based on 1 normalized pattern(s):

licensed under the terms of the gnu gpl license version 2

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 62 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.929121379@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# a59e5109 14-Dec-2014 Prarit Bhargava <prarit@redhat.com>

tools / cpupower: Fix no idle state information return value

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: Prarit Bhargava <prarit@redhat.com>
Acked-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>


# 788606cb 19-Jul-2014 Andrey Utkin <andrey.krieger.utkin@gmail.com>

PM / tools: cpupower: drop negativity check on unsigned value

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


# f4a5d17e 16-Nov-2013 Thomas Renninger <trenn@suse.de>

tools: cpupower: fix wrong err msg not supported vs not available

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: Thomas Renninger <trenn@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>


# 0924c369 28-Jun-2013 Thomas Renninger <trenn@suse.de>

cpupower: Implement disabling of cstate interface

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: Thomas Renninger <trenn@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>


# f605181a 28-Jun-2013 Thomas Renninger <trenn@suse.de>

cpupower: Make idlestate usage unsigned

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: Thomas Renninger <trenn@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>


# fb8eaeb7 27-Nov-2012 Palmer Cox <p@lmercox.com>

cpupower tools: Fix minor warnings

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: Palmer Cox <p@lmercox.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>


# 8e7fbcbc 09-Jan-2012 Peter Zijlstra <peterz@infradead.org>

sched: Remove stale power aware scheduling remnants and dysfunctional knobs

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: Peter 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@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>


# 7c74d2bc 11-Aug-2011 Thomas Renninger <trenn@suse.de>

cpupower: Better detect offlined CPUs

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: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>


# 2cd005ca 19-Apr-2011 Dominik Brodowski <linux@dominikbrodowski.net>

cpupowerutils: helpers - ConfigStyle bugfixes

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


# 7fe2f639 30-Mar-2011 Dominik Brodowski <linux@dominikbrodowski.net>

cpupowerutils - cpufrequtils extended with quite some features

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: Dominik Brodowski <linux@dominikbrodowski.net>