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Commit d192f93c authored by Olof Johansson's avatar Olof Johansson
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Merge tag 'tegra-for-3.7-maintainers' of...

Merge tag 'tegra-for-3.7-maintainers' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra into next/maintainers

* tag 'tegra-for-3.7-maintainers' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra:
  MAINTAINERS: tegra: remove Olof/Colin, add device tree files
  MAINTAINERS: add defconfig file to TEGRA section
  + sync with 3.6-rc4
parents adcb079f d5703bd3
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+11 −0
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@@ -5,4 +5,15 @@ Contact: "Ike Panhc <ike.pan@canonical.com>"
Description:
Description:
		Control the power of camera module. 1 means on, 0 means off.
		Control the power of camera module. 1 means on, 0 means off.


What:		/sys/devices/platform/ideapad/fan_mode
Date:		June 2012
KernelVersion:	3.6
Contact:	"Maxim Mikityanskiy <maxtram95@gmail.com>"
Description:
		Change fan mode
		There are four available modes:
			* 0 -> Super Silent Mode
			* 1 -> Standard Mode
			* 2 -> Dust Cleaning
			* 4 -> Efficient Thermal Dissipation Mode
+2 −2
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@@ -224,8 +224,8 @@ all your transactions.
</para>
</para>


<para>
<para>
Then at umount time , in your put_super() (2.4) or write_super() (2.5)
Then at umount time , in your put_super() you can then call journal_destroy()
you can then call journal_destroy() to clean up your in-core journal object.
to clean up your in-core journal object.
</para>
</para>


<para>
<para>
+1 −1
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@@ -125,7 +125,7 @@ the structure refers to a radio tuner the
<constant>V4L2_TUNER_CAP_NORM</constant> flags can't be used.</para>
<constant>V4L2_TUNER_CAP_NORM</constant> flags can't be used.</para>
<para>If multiple frequency bands are supported, then
<para>If multiple frequency bands are supported, then
<structfield>capability</structfield> is the union of all
<structfield>capability</structfield> is the union of all
<structfield>capability></structfield> fields of each &v4l2-frequency-band;.
<structfield>capability</structfield> fields of each &v4l2-frequency-band;.
</para></entry>
</para></entry>
	  </row>
	  </row>
	  <row>
	  <row>
+8 −2
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@@ -3,15 +3,21 @@
biodoc.txt
biodoc.txt
	- Notes on the Generic Block Layer Rewrite in Linux 2.5
	- Notes on the Generic Block Layer Rewrite in Linux 2.5
capability.txt
capability.txt
	- Generic Block Device Capability (/sys/block/<disk>/capability)
	- Generic Block Device Capability (/sys/block/<device>/capability)
cfq-iosched.txt
	- CFQ IO scheduler tunables
data-integrity.txt
	- Block data integrity
deadline-iosched.txt
deadline-iosched.txt
	- Deadline IO scheduler tunables
	- Deadline IO scheduler tunables
ioprio.txt
ioprio.txt
	- Block io priorities (in CFQ scheduler)
	- Block io priorities (in CFQ scheduler)
queue-sysfs.txt
	- Queue's sysfs entries
request.txt
request.txt
	- The members of struct request (in include/linux/blkdev.h)
	- The members of struct request (in include/linux/blkdev.h)
stat.txt
stat.txt
	- Block layer statistics in /sys/block/<dev>/stat
	- Block layer statistics in /sys/block/<device>/stat
switching-sched.txt
switching-sched.txt
	- Switching I/O schedulers at runtime
	- Switching I/O schedulers at runtime
writeback_cache_control.txt
writeback_cache_control.txt
+77 −0
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CFQ (Complete Fairness Queueing)
===============================

The main aim of CFQ scheduler is to provide a fair allocation of the disk
I/O bandwidth for all the processes which requests an I/O operation.

CFQ maintains the per process queue for the processes which request I/O
operation(syncronous requests). In case of asynchronous requests, all the
requests from all the processes are batched together according to their
process's I/O priority.

CFQ ioscheduler tunables
CFQ ioscheduler tunables
========================
========================


@@ -25,6 +36,72 @@ there are multiple spindles behind single LUN (Host based hardware RAID
controller or for storage arrays), setting slice_idle=0 might end up in better
controller or for storage arrays), setting slice_idle=0 might end up in better
throughput and acceptable latencies.
throughput and acceptable latencies.


back_seek_max
-------------
This specifies, given in Kbytes, the maximum "distance" for backward seeking.
The distance is the amount of space from the current head location to the
sectors that are backward in terms of distance.

This parameter allows the scheduler to anticipate requests in the "backward"
direction and consider them as being the "next" if they are within this
distance from the current head location.

back_seek_penalty
-----------------
This parameter is used to compute the cost of backward seeking. If the
backward distance of request is just 1/back_seek_penalty from a "front"
request, then the seeking cost of two requests is considered equivalent.

So scheduler will not bias toward one or the other request (otherwise scheduler
will bias toward front request). Default value of back_seek_penalty is 2.

fifo_expire_async
-----------------
This parameter is used to set the timeout of asynchronous requests. Default
value of this is 248ms.

fifo_expire_sync
----------------
This parameter is used to set the timeout of synchronous requests. Default
value of this is 124ms. In case to favor synchronous requests over asynchronous
one, this value should be decreased relative to fifo_expire_async.

slice_async
-----------
This parameter is same as of slice_sync but for asynchronous queue. The
default value is 40ms.

slice_async_rq
--------------
This parameter is used to limit the dispatching of asynchronous request to
device request queue in queue's slice time. The maximum number of request that
are allowed to be dispatched also depends upon the io priority. Default value
for this is 2.

slice_sync
----------
When a queue is selected for execution, the queues IO requests are only
executed for a certain amount of time(time_slice) before switching to another
queue. This parameter is used to calculate the time slice of synchronous
queue.

time_slice is computed using the below equation:-
time_slice = slice_sync + (slice_sync/5 * (4 - prio)). To increase the
time_slice of synchronous queue, increase the value of slice_sync. Default
value is 100ms.

quantum
-------
This specifies the number of request dispatched to the device queue. In a
queue's time slice, a request will not be dispatched if the number of request
in the device exceeds this parameter. This parameter is used for synchronous
request.

In case of storage with several disk, this setting can limit the parallel
processing of request. Therefore, increasing the value can imporve the
performace although this can cause the latency of some I/O to increase due
to more number of requests.

CFQ IOPS Mode for group scheduling
CFQ IOPS Mode for group scheduling
===================================
===================================
Basic CFQ design is to provide priority based time slices. Higher priority
Basic CFQ design is to provide priority based time slices. Higher priority
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