---

yaml
---
r: 328740
b: refs/heads/master
c: 057d51a
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 88d26136a256576e444db312179e17af6dd0ea87
+refs/heads/master: 057d51a1268fe4be039db8ff0791fcfcb63a4f1b

trunk/Documentation/ABI/testing/sysfs-bus-pci

@@ -210,3 +210,15 @@ Users:
 		firmware assigned instance number of the PCI
 		device that can help in understanding the firmware
 		intended order of the PCI device.
+
+What:		/sys/bus/pci/devices/.../d3cold_allowed
+Date:		July 2012
+Contact:	Huang Ying <ying.huang@intel.com>
+Description:
+		d3cold_allowed is bit to control whether the corresponding PCI
+		device can be put into D3Cold state.  If it is cleared, the
+		device will never be put into D3Cold state.  If it is set, the
+		device may be put into D3Cold state if other requirements are
+		satisfied too.  Reading this attribute will show the current
+		value of d3cold_allowed bit.  Writing this attribute will set
+		the value of d3cold_allowed bit.

trunk/Documentation/ABI/testing/sysfs-devices-system-cpu

@@ -176,3 +176,14 @@ Description:	Disable L3 cache indices
 		All AMD processors with L3 caches provide this functionality.
 		For details, see BKDGs at
 		http://developer.amd.com/documentation/guides/Pages/default.aspx
+
+
+What:		/sys/devices/system/cpu/cpufreq/boost
+Date:		August 2012
+Contact:	Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description:	Processor frequency boosting control
+
+		This switch controls the boost setting for the whole system.
+		Boosting allows the CPU and the firmware to run at a frequency
+		beyound it's nominal limit.
+		More details can be found in Documentation/cpu-freq/boost.txt

trunk/Documentation/ABI/testing/sysfs-platform-ideapad-laptop

@@ -5,4 +5,15 @@ Contact:	"Ike Panhc <ike.pan@canonical.com>"
 Description:
 		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
 

trunk/Documentation/DocBook/media/v4l/vidioc-g-tuner.xml

@@ -125,7 +125,7 @@ the structure refers to a radio tuner the
 <constant>V4L2_TUNER_CAP_NORM</constant> flags can't be used.</para>
 <para>If multiple frequency bands are supported, then
 <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>
 	  </row>
 	  <row>

trunk/Documentation/block/00-INDEX

@@ -3,15 +3,21 @@
 biodoc.txt
 	- Notes on the Generic Block Layer Rewrite in Linux 2.5
 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 IO scheduler tunables
 ioprio.txt
 	- Block io priorities (in CFQ scheduler)
+queue-sysfs.txt
+	- Queue's sysfs entries
 request.txt
 	- The members of struct request (in include/linux/blkdev.h)
 stat.txt
-	- Block layer statistics in /sys/block/<dev>/stat
+	- Block layer statistics in /sys/block/<device>/stat
 switching-sched.txt
 	- Switching I/O schedulers at runtime
 writeback_cache_control.txt

trunk/Documentation/block/cfq-iosched.txt

@@ -1,3 +1,14 @@
+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
 ========================
 
@@ -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
 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
 ===================================
 Basic CFQ design is to provide priority based time slices. Higher priority

trunk/Documentation/block/queue-sysfs.txt

@@ -9,20 +9,71 @@ These files are the ones found in the /sys/block/xxx/queue/ directory.
 Files denoted with a RO postfix are readonly and the RW postfix means
 read-write.
 
+add_random (RW)
+----------------
+This file allows to trun off the disk entropy contribution. Default
+value of this file is '1'(on).
+
+discard_granularity (RO)
+-----------------------
+This shows the size of internal allocation of the device in bytes, if
+reported by the device. A value of '0' means device does not support
+the discard functionality.
+
+discard_max_bytes (RO)
+----------------------
+Devices that support discard functionality may have internal limits on
+the number of bytes that can be trimmed or unmapped in a single operation.
+The discard_max_bytes parameter is set by the device driver to the maximum
+number of bytes that can be discarded in a single operation. Discard
+requests issued to the device must not exceed this limit. A discard_max_bytes
+value of 0 means that the device does not support discard functionality.
+
+discard_zeroes_data (RO)
+------------------------
+When read, this file will show if the discarded block are zeroed by the
+device or not. If its value is '1' the blocks are zeroed otherwise not.
+
 hw_sector_size (RO)
 -------------------
 This is the hardware sector size of the device, in bytes.
 
+iostats (RW)
+-------------
+This file is used to control (on/off) the iostats accounting of the
+disk.
+
+logical_block_size (RO)
+-----------------------
+This is the logcal block size of the device, in bytes.
+
 max_hw_sectors_kb (RO)
 ----------------------
 This is the maximum number of kilobytes supported in a single data transfer.
 
+max_integrity_segments (RO)
+---------------------------
+When read, this file shows the max limit of integrity segments as
+set by block layer which a hardware controller can handle.
+
 max_sectors_kb (RW)
 -------------------
 This is the maximum number of kilobytes that the block layer will allow
 for a filesystem request. Must be smaller than or equal to the maximum
 size allowed by the hardware.
 
+max_segments (RO)
+-----------------
+Maximum number of segments of the device.
+
+max_segment_size (RO)
+---------------------
+Maximum segment size of the device.
+
+minimum_io_size (RO)
+--------------------
+This is the smallest preferred io size reported by the device.
+
 nomerges (RW)
 -------------
 This enables the user to disable the lookup logic involved with IO
@@ -45,11 +96,24 @@ per-block-cgroup request pool.  IOW, if there are N block cgroups,
 each request queue may have upto N request pools, each independently
 regulated by nr_requests.
 
+optimal_io_size (RO)
+--------------------
+This is the optimal io size reported by the device.
+
+physical_block_size (RO)
+------------------------
+This is the physical block size of device, in bytes.
+
 read_ahead_kb (RW)
 ------------------
 Maximum number of kilobytes to read-ahead for filesystems on this block
 device.
 
+rotational (RW)
+---------------
+This file is used to stat if the device is of rotational type or
+non-rotational type.
+
 rq_affinity (RW)
 ----------------
 If this option is '1', the block layer will migrate request completions to the

trunk/Documentation/cpu-freq/boost.txt

@@ -0,0 +1,93 @@
+Processor boosting control
+
+	- information for users -
+
+Quick guide for the impatient:
+--------------------
+/sys/devices/system/cpu/cpufreq/boost
+controls the boost setting for the whole system. You can read and write
+that file with either "0" (boosting disabled) or "1" (boosting allowed).
+Reading or writing 1 does not mean that the system is boosting at this
+very moment, but only that the CPU _may_ raise the frequency at it's
+discretion.
+--------------------
+
+Introduction
+-------------
+Some CPUs support a functionality to raise the operating frequency of
+some cores in a multi-core package if certain conditions apply, mostly
+if the whole chip is not fully utilized and below it's intended thermal
+budget. This is done without operating system control by a combination
+of hardware and firmware.
+On Intel CPUs this is called "Turbo Boost", AMD calls it "Turbo-Core",
+in technical documentation "Core performance boost". In Linux we use
+the term "boost" for convenience.
+
+Rationale for disable switch
+----------------------------
+
+Though the idea is to just give better performance without any user
+intervention, sometimes the need arises to disable this functionality.
+Most systems offer a switch in the (BIOS) firmware to disable the
+functionality at all, but a more fine-grained and dynamic control would
+be desirable:
+1. While running benchmarks, reproducible results are important. Since
+   the boosting functionality depends on the load of the whole package,
+   single thread performance can vary. By explicitly disabling the boost
+   functionality at least for the benchmark's run-time the system will run
+   at a fixed frequency and results are reproducible again.
+2. To examine the impact of the boosting functionality it is helpful
+   to do tests with and without boosting.
+3. Boosting means overclocking the processor, though under controlled
+   conditions. By raising the frequency and the voltage the processor
+   will consume more power than without the boosting, which may be
+   undesirable for instance for mobile users. Disabling boosting may
+   save power here, though this depends on the workload.
+
+
+User controlled switch
+----------------------
+
+To allow the user to toggle the boosting functionality, the acpi-cpufreq
+driver exports a sysfs knob to disable it. There is a file:
+/sys/devices/system/cpu/cpufreq/boost
+which can either read "0" (boosting disabled) or "1" (boosting enabled).
+Reading the file is always supported, even if the processor does not
+support boosting. In this case the file will be read-only and always
+reads as "0". Explicitly changing the permissions and writing to that
+file anyway will return EINVAL.
+
+On supported CPUs one can write either a "0" or a "1" into this file.
+This will either disable the boost functionality on all cores in the
+whole system (0) or will allow the hardware to boost at will (1).
+
+Writing a "1" does not explicitly boost the system, but just allows the
+CPU (and the firmware) to boost at their discretion. Some implementations
+take external factors like the chip's temperature into account, so
+boosting once does not necessarily mean that it will occur every time
+even using the exact same software setup.
+
+
+AMD legacy cpb switch
+---------------------
+The AMD powernow-k8 driver used to support a very similar switch to
+disable or enable the "Core Performance Boost" feature of some AMD CPUs.
+This switch was instantiated in each CPU's cpufreq directory
+(/sys/devices/system/cpu[0-9]*/cpufreq) and was called "cpb".
+Though the per CPU existence hints at a more fine grained control, the
+actual implementation only supported a system-global switch semantics,
+which was simply reflected into each CPU's file. Writing a 0 or 1 into it
+would pull the other CPUs to the same state.
+For compatibility reasons this file and its behavior is still supported
+on AMD CPUs, though it is now protected by a config switch
+(X86_ACPI_CPUFREQ_CPB). On Intel CPUs this file will never be created,
+even with the config option set.
+This functionality is considered legacy and will be removed in some future
+kernel version.
+
+More fine grained boosting control
+----------------------------------
+
+Technically it is possible to switch the boosting functionality at least
+on a per package basis, for some CPUs even per core. Currently the driver
+does not support it, but this may be implemented in the future.

trunk/Documentation/cpuidle/sysfs.txt

@@ -76,9 +76,17 @@ total 0
 
 
 * desc : Small description about the idle state (string)
-* disable : Option to disable this idle state (bool)
+* disable : Option to disable this idle state (bool) -> see note below
 * latency : Latency to exit out of this idle state (in microseconds)
 * name : Name of the idle state (string)
 * power : Power consumed while in this idle state (in milliwatts)
 * time : Total time spent in this idle state (in microseconds)
 * usage : Number of times this state was entered (count)
+
+Note:
+The behavior and the effect of the disable variable depends on the
+implementation of a particular governor. In the ladder governor, for
+example, it is not coherent, i.e. if one is disabling a light state,
+then all deeper states are disabled as well, but the disable variable
+does not reflect it. Likewise, if one enables a deep state but a lighter
+state still is disabled, then this has no effect.