Merge commit 'linus/master' into sched-fixes-for-linus

# cscope files

cscope.*

ncscope.*

*.orig

*.rej

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\#*#

	non-block filesystems which provide their own BDI, such as NFS

	and FUSE.

MAJOR:MINOR-fuseblk

	Value of st_dev on fuseblk filesystems.

default

	The default backing dev, used for non-block device backed

</sect1>

</chapter>

<chapter id="trylock-functions">

 <title>The trylock Functions</title>

  <para>

   There are functions that try to acquire a lock only once and immediately

   return a value telling about success or failure to acquire the lock.

   They can be used if you need no access to the data protected with the lock

   when some other thread is holding the lock. You should acquire the lock

   later if you then need access to the data protected with the lock.

  </para>

  <para>

    <function>spin_trylock()</function> does not spin but returns non-zero if

    it acquires the spinlock on the first try or 0 if not. This function can

    be used in all contexts like <function>spin_lock</function>: you must have

    disabled the contexts that might interrupt you and acquire the spin lock.

  </para>

  <para>

    <function>mutex_trylock()</function> does not suspend your task

    but returns non-zero if it could lock the mutex on the first try

    or 0 if not. This function cannot be safely used in hardware or software

    interrupt contexts despite not sleeping.

  </para>

</chapter>

  <chapter id="Examples">

   <title>Common Examples</title>

    <para>

intervals the CPU needs to be on average more than 80% in use to then

decide that the CPU frequency needs to be increased.  

sampling_down_factor: this parameter controls the rate that the CPU

makes a decision on when to decrease the frequency.  When set to its

default value of '5' it means that at 1/5 the sampling_rate the kernel

makes a decision to lower the frequency.  Five "lower rate" decisions

have to be made in a row before the CPU frequency is actually lower.

If set to '1' then the frequency decreases as quickly as it increases,

if set to '2' it decreases at half the rate of the increase.

ignore_nice_load: this parameter takes a value of '0' or '1'. When

set to '0' (its default), all processes are counted towards the

'cpu utilisation' value.  When set to '1', the processes that are

Kernel driver ibmaem

======================

Supported systems:

  * Any recent IBM System X server with Active Energy Manager support.

    This includes the x3350, x3550, x3650, x3655, x3755, x3850 M2,

    x3950 M2, and certain HS2x/LS2x/QS2x blades.  The IPMI host interface

    driver ("ipmi-si") needs to be loaded for this driver to do anything.

    Prefix: 'ibmaem'

    Datasheet: Not available

Author: Darrick J. Wong

Description

-----------

This driver implements sensor reading support for the energy and power

meters available on various IBM System X hardware through the BMC.  All

sensor banks will be exported as platform devices; this driver can talk

to both v1 and v2 interfaces.  This driver is completely separate from the

older ibmpex driver.

The v1 AEM interface has a simple set of features to monitor energy use.

There is a register that displays an estimate of raw energy consumption

since the last BMC reset, and a power sensor that returns average power

use over a configurable interval.

The v2 AEM interface is a bit more sophisticated, being able to present

a wider range of energy and power use registers, the power cap as

set by the AEM software, and temperature sensors.

Special Features

----------------

The "power_cap" value displays the current system power cap, as set by

the Active Energy Manager software.  Setting the power cap from the host

is not currently supported.