Hi all,
These are new releases of dm-ioband and blkio-cgroup. The major change
of these releases is that a hierarchical configuration is supported,
a parent cgroup's bandwidth is distributed to its children. The
hierarchical configuration is available when using dm-ioband and
blkio-cgroup together. Please refer to the documentation included in
this series of patches on how to use it.
The summary of the changes are below:
dm-ioband v1.13.0
- Introduce a hierarchical grouping mechanism for blkio-cgroup.
- Change the dmsetup status outputs to be similar to
/proc/diskstats and /sys/block/dev/stat files.
blkio-cgroup v12
- dm-ioband can be configured in a hierarchical manner through the
cgroup interface.
- blkio.stat file is added which shows IO statistics per cgroup.
TODO
- Borrowing and lending bandwidth between a parent and children if
spare bandwidth is available in them.
These patches can be applied to kernel 2.6.31
The list of the patches:
[PATCH 1/9] I/O bandwidth controller and BIO tracking
[PATCH 2/9] dm-ioband-1.13.0: All-in-one patch
[PATCH 3/9] blkio-cgroup-v12: The new page_cgroup framework
[PATCH 4/9] blkio-cgroup-v12: Refactoring io-context initialization
[PATCH 5/9] blkio-cgroup-v12: The body of blkio-cgroup
[PATCH 6/9] blkio-cgroup-v12: Page tracking hooks
[PATCH 7/9] blkio-cgroup-v12: The document of blkio-cgroup
[PATCH 8/9] blkio-cgroup-v12: Add a cgroup support to dm-ioband
[PATCH 9/9] blkio-cgroup-v12: The document of a cgroup support for dm-ioband
About dm-ioband
dm-ioband is an I/O bandwidth controller implemented as a
device-mapper driver and can control bandwidth on per partition, per
user, per process, per virtual machine (such as KVM or Xen) basis.
About blkio-cgruop
blkio-cgroup is a block I/O tracking mechanism implemented on the
cgroup memory subsystem. Using this feature the owners of any type
of I/O can be determined. This allows dm-ioband to control block I/O
bandwidth even when it is accepting delayed write requests.
dm-ioband can find the cgroup of each request. It is also for
possible that others working on I/O bandwidth throttling to use this
functionality to control asynchronous I/O with a little enhancement.
Please visit our website, the patches and more information are available.
Linux Block I/O Bandwidth Control Project
http://sourceforge.net/apps/trac/ioband/
I'd like to get some feedbacks from the list. Any comments are
appreciated.
Thanks,
Ryo Tsuruta
The body of dm-ioband. This patch is an all-in-one patch of dm-ioband
so that it replaces dm-add-ioband.patch in the device-mapper development tree.
Signed-off-by: Ryo Tsuruta <[email protected]>
Signed-off-by: Hirokazu Takahashi <[email protected]>
---
Documentation/device-mapper/ioband.txt | 1113 +++++++++++++++++++++++++
Documentation/device-mapper/range-bw.txt | 99 ++
drivers/md/Kconfig | 13
drivers/md/Makefile | 3
drivers/md/dm-ioband-ctl.c | 1357 +++++++++++++++++++++++++++++++
drivers/md/dm-ioband-policy.c | 543 ++++++++++++
drivers/md/dm-ioband-rangebw.c | 669 +++++++++++++++
drivers/md/dm-ioband-type.c | 76 +
drivers/md/dm-ioband.h | 231 +++++
include/trace/events/dm-ioband.h | 242 +++++
10 files changed, 4346 insertions(+)
Index: linux-2.6.31/Documentation/device-mapper/ioband.txt
===================================================================
--- /dev/null
+++ linux-2.6.31/Documentation/device-mapper/ioband.txt
@@ -0,0 +1,1113 @@
+ Block I/O bandwidth control: dm-ioband
+
+ -------------------------------------------------------
+
+ Table of Contents
+
+ [1]What's dm-ioband all about?
+
+ [2]Differences from the CFQ I/O scheduler
+
+ [3]How dm-ioband works.
+
+ [4]Setup and Installation
+
+ [5]Getting started
+
+ [6]Command Reference
+
+ [7]Examples
+
+What's dm-ioband all about?
+
+ dm-ioband is an I/O bandwidth controller implemented as a device-mapper
+ driver. Several jobs using the same block device have to share the
+ bandwidth of the device. dm-ioband gives bandwidth to each job according
+ to bandwidth control policies.
+
+ A job is a group of processes with the same pid or pgrp or uid or a
+ virtual machine such as KVM or Xen. A job can also be a cgroup by applying
+ the blkio-cgroup patch, which can be found at
+ http://sourceforge.net/apps/trac/ioband/.
+
+ +-------+ +-------+ +-------+ +-------+ +-------+ +-------+
+ |cgroup | |cgroup | | the | | pid | | pid | | the | jobs
+ | A | | B | |others | | X | | Y | |others |
+ +---|---+ +---|---+ +---|---+ +---|---+ +---|---+ +---|---+
+ | | | | | |
+ +-----|---------|---------|----+----|---------|---------|-----+
+ | | /dev/mapper/disk1 | | | /dev/mapper/disk2 | |
+ |-----|---------|---------|----+----|---------|---------|-----|
+ | +---V---+ +---V---+ +---V---+ +---V---+ +---V---+ +---V---+ |
+ | | ioband| | ioband| |default| | ioband| | ioband| |default| |
+ | | group | | group | | group | | group | | group | | group | | dm-ioband
+ | |-------+-+-------+-+-------+-+-------+-+-------+-+-------| |
+ | | bandwidth control | |
+ | +-------------|-----------------------------|-------------+ |
+ ---------------|-----------------------------|---------------
+ | |
+ +---------------V--------------+--------------V---------------+
+ | /dev/sdb1 | /dev/sdb2 | partitions
+ +------------------------------+------------------------------+
+
+
+ --------------------------------------------------------------------------
+
+Differences from the CFQ I/O scheduler
+
+ Dm-ioband is flexible to configure the bandwidth settings.
+
+ Dm-ioband can work with any type of I/O scheduler such as the NOOP
+ scheduler, which is often chosen for high-end storages, since it is
+ implemented outside the I/O scheduling layer. It allows both of partition
+ based bandwidth control and job --- a group of processes --- based
+ control. In addition, it can set different configuration on each block
+ device to control its bandwidth.
+
+ Meanwhile the current implementation of the CFQ scheduler has 8 IO
+ priority levels and all jobs whose processes have the same IO priority
+ share the bandwidth assigned to this level between them. And IO priority
+ is an attribute of a process, so that it equally effects to all block
+ devices.
+
+ --------------------------------------------------------------------------
+
+How dm-ioband works.
+
+ The bandwidth of each job is determined by a bandwidth control policy.
+ dm-ioband provides three kinds of policies "weight", "weight-iosize" and
+ "range-bw", and a user can select one of them at the time of setup.
+
+ --------------------------------------------------------------------------
+
+ weight and weight-iosize policy
+
+ Every ioband device has one ioband group, which by default is called the
+ default group, and can also have extra ioband groups in the ioband device.
+ Each ioband group has its own weight and tokens. The amount of tokens are
+ determined proportional to the weight of each ioband group.
+
+ The ioband group can pass on I/O requests that its job issues to the
+ underlying layer so long as it has tokens left, while requests are blocked
+ if there aren't any tokens left in the ioband group. The tokens are
+ refilled once all of the ioband groups that have requests on a given
+ underlying block device use up their tokens.
+
+ The weight policy lets dm-ioband consume one token per one I/O request.
+ The weight-iosize policy lets dm-ioband consume one token per one I/O
+ sector, for example, one I/O request which consists of 4Kbytes (512bytes *
+ 8 sectors) read consumes 8 tokens.
+
+ With this approach, a job running on the ioband group with large weight
+ is guaranteed a wide I/O bandwidth.
+
+ --------------------------------------------------------------------------
+
+ range-bw policy
+
+ range-bw means the predicable I/O bandwidth with minimum and maximum
+ value defined by administrator. And it is also possible to set up only
+ maximum value for only I/O limitation. So, you can define the specific and
+ fixed bandwidth to satisfy I/O requirement regardless of whole I/O
+ bandwidth.
+
+ Minimum I/O bandwidth is to guarantee the stable performance or
+ reliability of specific process group and maximum bandwidth is to throttle
+ the unnecessary I/O usage or to reserve the I/O bandwidth for another use.
+ So range-bw supports adequate and predicable I/O bandwidth between minimum
+ and maximum value.
+
+ The setting unit is based on Kbytes/sec. If you want to allocate
+ 3M~5Mbytes/sec I/O bandwidth to X group, you should set 3000 to min-bw,
+ 5000 to max-bw.
+
+ Attention
+
+ Although range-bw supports the predicable I/O bandwidth, it should be
+ configured in the scope of total I/O bandwidth of the I/O system to
+ guarantee the minimum I/O requirement. For example, if total I/O bandwidth
+ is 40Mbytes/sec, the summary of I/O bandwidth configured in each process
+ group should be equal or smaller than 40Mbytes/sec. So, we need to check
+ total I/O bandwidth before set it up.
+
+ --------------------------------------------------------------------------
+
+Setup and Installation
+
+ Build a kernel with these options enabled:
+
+ CONFIG_MD
+ CONFIG_BLK_DEV_DM
+ CONFIG_DM_IOBAND
+
+
+ If compiled as module, use modprobe to load dm-ioband.
+
+ # make modules
+ # make modules_install
+ # depmod -a
+ # modprobe dm-ioband
+
+
+ "dmsetup targets" command shows all available device-mapper targets.
+ "ioband" and the version number are displayed when dm-ioband has been
+ loaded.
+
+ # dmsetup targets | grep ioband
+ ioband v1.0.0
+
+
+ --------------------------------------------------------------------------
+
+Getting started
+
+ The following is a brief description how to control the I/O bandwidth of
+ disks. In this description, we'll take one disk with two partitions as an
+ example target.
+
+ --------------------------------------------------------------------------
+
+ Create and map ioband devices
+
+ Create two ioband devices "ioband1" and "ioband2". "ioband1" is mapped
+ to "/dev/sda1" and has a weight of 40. "ioband2" is mapped to "/dev/sda2"
+ and has a weight of 10. "ioband1" can use 80% --- 40/(40+10)*100 --- of
+ the bandwidth of "/dev/sda" while "ioband2" can use 20%.
+
+ # echo "0 $(blockdev --getsize /dev/sda1) ioband /dev/sda1 1 0 0 none" \
+ "weight 0 :40" | dmsetup create ioband1
+ # echo "0 $(blockdev --getsize /dev/sda2) ioband /dev/sda2 1 0 0 none" \
+ "weight 0 :10" | dmsetup create ioband2
+
+
+ If the commands are successful then the device files
+ "/dev/mapper/ioband1" and "/dev/mapper/ioband2" will have been created.
+
+ --------------------------------------------------------------------------
+
+ Additional bandwidth control
+
+ In this example two extra ioband groups are created on "ioband1."
+
+ First, set the ioband group type as user. Next, create two ioband groups
+ that have id 1000 and 2000. Then, give weights of 30 and 20 to the ioband
+ groups respectively.
+
+ # dmsetup message ioband1 0 type user
+ # dmsetup message ioband1 0 attach 1000
+ # dmsetup message ioband1 0 attach 2000
+ # dmsetup message ioband1 0 weight 1000:30
+ # dmsetup message ioband1 0 weight 2000:20
+
+
+ Now the processes owned by uid 1000 can use 30% --- 30/(30+20+40+10)*100
+ --- of the bandwidth of "/dev/sda" when the processes issue I/O requests
+ through "ioband1." The processes owned by uid 2000 can use 20% of the
+ bandwidth likewise.
+
+ Table 1. Weight assignments
+
+ +----------------------------------------------------------------+
+ | ioband device | ioband group | ioband weight |
+ |---------------+--------------------------------+---------------|
+ | ioband1 | user id 1000 | 30 |
+ |---------------+--------------------------------+---------------|
+ | ioband1 | user id 2000 | 20 |
+ |---------------+--------------------------------+---------------|
+ | ioband1 | default group(the other users) | 40 |
+ |---------------+--------------------------------+---------------|
+ | ioband2 | default group | 10 |
+ +----------------------------------------------------------------+
+
+ --------------------------------------------------------------------------
+
+ Remove the ioband devices
+
+ Remove the ioband devices when no longer used.
+
+ # dmsetup remove ioband1
+ # dmsetup remove ioband2
+
+
+ --------------------------------------------------------------------------
+
+Command Reference
+
+ Create an ioband device
+
+ SYNOPSIS
+
+ dmsetup create IOBAND_DEVICE
+
+ DESCRIPTION
+
+ Create an ioband device with the given name IOBAND_DEVICE.
+ Generally, dmsetup reads a table from standard input. Each line of
+ the table specifies a single target and is of the form:
+
+ start_sector num_sectors "ioband" device_file ioband_device_id \
+ io_throttle io_limit ioband_group_type policy policy_args...
+
+
+ start_sector, num_sectors
+
+ The sector range of the underlying device where
+ dm-ioband maps.
+
+ ioband
+
+ Specify the string "ioband" as a target type.
+
+ device_file
+
+ Underlying device name.
+
+ ioband_device_id
+
+ The ID for an ioband device can be symbolic,
+ numeric, or mixed. The same ID must be set among the
+ ioband devices that share the same bandwidth. This is
+ useful for grouping disk drives partitioned from one
+ disk drive such as RAID drive or LVM logical striped
+ volume.
+
+ io_throttle
+
+ When a device has a lot of tokens, and the number
+ of in-flight I/Os in dm-ioband exceeds io_throttle,
+ dm-ioband gives priority to the device and issues
+ I/Os to the device until no tokens of the device are
+ left. If 0 is specified, the default value is used.
+ This setting applies all ioband devices which has the
+ same ioband device ID as you specified by
+ "ioband_device_id."
+
+ io_limit
+
+ Dm-ioband blocks all I/O requests for IOBAND_DEVICE
+ when the number of BIOs in progress exceeds this
+ value. If 0 is specified, the default value is used.
+ This setting applies all ioband devices which has the
+ same ioband device ID as you specified by
+ "ioband_device_id."
+
+ ioband_group_type
+
+ Specify how to evaluate the ioband group ID. The
+ selectable group types are "none", "user", "gid",
+ "pid" or "pgrp." The type "cgroup" is enabled by
+ applying the blkio-cgroup patch. Specify "none" if
+ you don't need any ioband groups other than the
+ default ioband group.
+
+ policy and policy_args
+
+ Specify a bandwidth control policy. The selectable
+ policies are "weight", "weight-iosize" or "range-bw."
+ This setting applies all ioband devices which has the
+ same ioband device ID as you specified by
+ "ioband_device_id."
+
+ policy_args are specific for each policy. See below
+ for information on each policy.
+
+ WEIGHT AND WEIGHT-IOSIZE POLICIES
+
+ The "weight" and "weight-iosize" policies distribute bandwidth
+ proportional to the weight of each ioband group. Each ioband group
+ is charged on an I/O count basis when the "weight" policy is used
+ and an I/O size basis when the "weight-iosize" policy is used. The
+ arguments are of the form:
+
+ token_base :weight [ioband_group_id:weight...]
+
+
+ token_base
+
+ The number of tokens which specified by token_base
+ will be distributed to all ioband groups proportional
+ to the weight of each ioband group. If 0 is
+ specified, the default value is used. This setting
+ applies all ioband devices which has the same ioband
+ device ID as you specified by "ioband_device_id."
+
+ :weight
+
+ Set the weight of the default ioband group.
+
+ ioband_group_id:weight
+
+ Create an extra ioband group with an
+ ioband_group_id and set its weight. The
+ ioband_group_id is an identification number and
+ corresponds to pid, pgrp , uid and so on which depend
+ on ioband group type settings.
+
+ RANGE-BW POLICY
+
+ The "range-bw" policy distributes the predicable bandwidth to
+ each group according to the values of minimum and maximum
+ bandwidth value. And range-bw is not based on I/O token which is
+ usually grant for I/O authority.
+
+ So, "0" value is used for token_base parameter in range-bw
+ policy. And both parameters, min-bw and max-bw, are generally used
+ together, but, max-bw can be used alone for only limitation. The
+ arguments are of the form:
+
+ token_base :min-bw:max-bw [ioband_group_id:min-bw:max-bw...]
+
+
+ token_base
+
+ "0" is used, because it is not meaningful in this
+ policy
+
+ min-bw
+
+ Set the minimum bandwidth of the default ioband
+ group. This parameter can't be used alone.
+
+ max-bw
+
+ Set the maximum bandwidth of the default ioband
+ group.
+
+ ioband_group_id:min-bw:max-bw
+
+ Create an extra ioband group with an
+ ioband_group_id and set its min and max bandwidth.
+ The ioband_group_id is an identification number and
+ corresponds to pid, pgrp , uid and so on which depend
+ on ioband group type settings.
+
+ EXAMPLE
+
+ Create an ioband device with the following parameters:
+
+ * Starting sector = "0"
+
+ * The number of sectors = "$(blockdev --getsize /dev/sda1)"
+
+ * Target type = "ioband"
+
+ * Underlying device name = "/dev/sda1"
+
+ * Ioband device ID = "share1"
+
+ * I/O throttle = "10"
+
+ * I/O limit = "400"
+
+ * Ioband group type = "user"
+
+ * Bandwidth control policy = "weight"
+
+ * Token base = "2048"
+
+ * Weight for the default ioband group = "100"
+
+ * Weight for the ioband group 1000 = "80"
+
+ * Weight for the ioband group 2000 = "20"
+
+ * Ioband device name = "ioband1"
+
+ # echo "0 $(blockdev --getsize /dev/sda1) ioband /dev/sda1" \
+ "share1 10 400 user weight 2048 :100 1000:80 2000:20" \
+ | dmsetup create ioband1
+
+
+ Create two device groups (ID=1,2). The bandwidths of these
+ device groups will be individually controlled.
+
+ # echo "0 $(blockdev --getsize /dev/sda1) ioband /dev/sda1 1" \
+ "0 0 none weight 0 :80" | dmsetup create ioband1
+ # echo "0 $(blockdev --getsize /dev/sda2) ioband /dev/sda2 1" \
+ "0 0 none weight 0 :20" | dmsetup create ioband2
+ # echo "0 $(blockdev --getsize /dev/sdb3) ioband /dev/sdb3 2" \
+ "0 0 none weight 0 :60" | dmsetup create ioband3
+ # echo "0 $(blockdev --getsize /dev/sdb4) ioband /dev/sdb4 2" \
+ "0 0 none weight 0 :40" | dmsetup create ioband4
+
+
+ --------------------------------------------------------------------------
+
+ Remove the ioband device
+
+ SYNOPSIS
+
+ dmsetup remove IOBAND_DEVICE
+
+ DESCRIPTION
+
+ Remove the specified ioband device IOBAND_DEVICE. All the band
+ groups attached to the ioband device are also removed
+ automatically.
+
+ EXAMPLE
+
+ Remove ioband device "ioband1."
+
+ # dmsetup remove ioband1
+
+
+ --------------------------------------------------------------------------
+
+ Set an ioband group type
+
+ SYNOPSIS
+
+ dmsetup message IOBAND_DEVICE 0 type TYPE
+
+ DESCRIPTION
+
+ Set an ioband group type of IOBAND_DEVICE. TYPE must be one of
+ "none", "user", "gid", "pid" or "pgrp." The type "cgroup" is
+ enabled by applying the blkio-cgroup patch. Once the type is set,
+ new ioband groups can be created on IOBAND_DEVICE.
+
+ EXAMPLE
+
+ Set the ioband group type of ioband device "ioband1" to "user."
+
+ # dmsetup message ioband1 0 type user
+
+
+ --------------------------------------------------------------------------
+
+ Create an ioband group
+
+ SYNOPSIS
+
+ dmsetup message IOBAND_DEVICE 0 attach ID
+
+ DESCRIPTION
+
+ Create an ioband group and attach it to IOBAND_DEVICE. ID
+ specifies user-id, group-id, process-id or process-group-id
+ depending the ioband group type of IOBAND_DEVICE.
+
+ EXAMPLE
+
+ Create an ioband group which consists of all processes with
+ user-id 1000 and attach it to ioband device "ioband1."
+
+ # dmsetup message ioband1 0 type user
+ # dmsetup message ioband1 0 attach 1000
+
+
+ --------------------------------------------------------------------------
+
+ Detach the ioband group
+
+ SYNOPSIS
+
+ dmsetup message IOBAND_DEVICE 0 detach ID
+
+ DESCRIPTION
+
+ Detach the ioband group specified by ID from ioband device
+ IOBAND_DEVICE.
+
+ EXAMPLE
+
+ Detach the ioband group with ID "2000" from ioband device
+ "ioband2."
+
+ # dmsetup message ioband2 0 detach 1000
+
+
+ --------------------------------------------------------------------------
+
+ Set bandwidth control policy
+
+ SYNOPSIS
+
+ dmsetup message IOBAND_DEVICE 0 policy POLICY
+
+ DESCRIPTION
+
+ Set POLICY to a bandwidth control policy. The selectable
+ policies are "weight", "weight-iosize" and "range-bw." This
+ setting applies all ioband devices which has the same ioband
+ device ID as IOBAND_DEVICE.
+
+ weight
+
+ This policy distributes bandwidth proportional to
+ the weight of each ioband group. Each ioband group is
+ charged on an I/O count basis.
+
+ weight-iosize
+
+ This policy distributes bandwidth proportional to
+ the weight of each ioband group. Each ioband group is
+ charged on an I/O size basis.
+
+ range-bw
+
+ This policy guarantees minimum bandwidth and limits
+ maximum bandwidth for each ioband group.
+
+ EXAMPLE
+
+ Set bandwidth control policy of ioband devices which have the
+ same ioband device ID as "ioband1" to "weight-iosize."
+
+ # dmsetup message ioband1 0 policy weight-iosize
+
+
+ --------------------------------------------------------------------------
+
+ Set the weight of an ioband group
+
+ SYNOPSIS
+
+ dmsetup message IOBAND_DEVICE 0 weight VAL
+
+ dmsetup message IOBAND_DEVICE 0 weight ID:VAL
+
+ DESCRIPTION
+
+ Set the weight of the ioband group which belongs to
+ IOBAND_DEVICE. The group is determined by ID. If ID: is omitted,
+ the default ioband group is chosen.
+
+ The following example means that "ioband1" can use 80% ---
+ 40/(40+10)*100 --- of the bandwidth of the underlying block device
+ while "ioband2" can use 20%.
+
+ # dmsetup message ioband1 0 weight 40
+ # dmsetup message ioband2 0 weight 10
+
+
+ The following lines have the same effect as the above:
+
+ # dmsetup message ioband1 0 weight 4
+ # dmsetup message ioband2 0 weight 1
+
+
+ VAL must be an integer larger than 0. The default value, which
+ is assigned to newly created ioband groups, is 100.
+
+ EXAMPLE
+
+ Set the weight of the default ioband group of "ioband1" to 40.
+
+ # dmsetup message ioband1 0 weight 40
+
+
+ Set the weight of the ioband group of "ioband1" with ID "1000"
+ to 10.
+
+ # dmsetup message ioband1 0 weight 1000:10
+
+
+ --------------------------------------------------------------------------
+
+ Set the range-bw of an ioband group
+
+ SYNOPSIS
+
+ dmsetup -- message IOBAND_DEVICE 0 range-bw -1:MIN:MAX
+
+ dmsetup message IOBAND_DEVICE 0 range-bw ID:MIN-BW:MAX-BW
+
+ DESCRIPTION
+
+ Set the range-bw of the ioband group which belongs to
+ IOBAND_DEVICE. The group is determined by ID. If -1 is specified
+ as ID, the default ioband group is chosen.
+
+ The following example means that "ioband1" can use
+ 5M~6Mbytes/sec bandwidth of the underlying block device while
+ "ioband2" can use 900K~1Mbytes/sec bandwidth.
+
+ # dmsetup message -- ioband1 0 range-bw -1:5000:6000
+
+ # dmsetup message -- ioband2 0 range-bw -1:900:1000
+
+
+ MIN-BW and MAX-BW and must be an integer larger than 0 and its
+ unit is Kbyte/sec.
+
+ EXAMPLE
+
+ Set the range-bw of the default ioband group of "ioband1" to
+ 200K~300K I/O bandwidth.
+
+ # dmsetup -- message ioband1 0 range-bw -1:200:300
+
+
+ Set the weight of the ioband group of "ioband1" with ID "1000"
+ to 10M~12M I/O bandwidth.
+
+ # dmsetup message ioband1 0 range-bw 1000:10000:12000
+
+
+ --------------------------------------------------------------------------
+
+ Set the number of tokens
+
+ SYNOPSIS
+
+ dmsetup message IOBAND_DEVICE 0 token VAL
+
+ DESCRIPTION
+
+ The number of tokens will be distributed to all ioband groups
+ proportional to the weight of each ioband group. If 0 is
+ specified, the default value is used. This setting applies all
+ ioband devices which has the same ioband device ID as
+ IOBAND_DEVICE
+
+ EXAMPLE
+
+ Set the number of tokens to 256.
+
+ # dmsetup message ioband1 0 token 256
+
+
+ --------------------------------------------------------------------------
+
+ Set a limit of how many tokens are carried over
+
+ SYNOPSIS
+
+ dmsetup message IOBAND_DEVICE 0 carryover VAL
+
+ DESCRIPTION
+
+ When dm-ioband tries to refill an ioband group with tokens after
+ another ioband group is already refilled several times, dm-ioband
+ determines the number of tokens to refill by multiplying the
+ number of tokens refilled once by the smaller of how many times
+ the other group is already refilled or this limit. If 0 is
+ specified, the default value is used. This setting applies all
+ ioband devices which has the same ioband device ID as
+ IOBAND_DEVICE.
+
+ EXAMPLE
+
+ Set a limit for "ioband1" to 2.
+
+ # dmsetup message ioband1 0 carryover 2
+
+
+ --------------------------------------------------------------------------
+
+ Set I/O throttling
+
+ SYNOPSIS
+
+ dmsetup message IOBAND_DEVICE 0 io_throttle VAL
+
+ DESCRIPTION
+
+ When a device has a lot of tokens, and the number of in-flight
+ I/Os in dm-ioband exceeds io_throttle, dm-ioband gives priority to
+ the device and issues I/Os to the device until no tokens of the
+ device are left. If 0 is specified, the default value is used.
+ This setting applies all ioband devices which has the same ioband
+ device ID as you specified by "ioband_device_id."
+
+ EXAMPLE
+
+ Set the I/O throttling value of "ioband1" to 16.
+
+ # dmsetup message ioband1 0 io_throttle 16
+
+
+ --------------------------------------------------------------------------
+
+ Set I/O limiting
+
+ SYNOPSIS
+
+ dmsetup message IOBAND_DEVICE 0 io_limit VAL
+
+ DESCRIPTION
+
+ Dm-ioband blocks all I/O requests for IOBAND_DEVICE when the
+ number of BIOs in progress exceeds this value. If 0 is specified,
+ the default value is used. This setting applies all ioband devices
+ which has the same ioband device ID as IOBAND_DEVICE.
+
+ EXAMPLE
+
+ Set the I/O limiting value of "ioband1" to 128.
+
+ # dmsetup message ioband1 0 io_limit 128
+
+
+ --------------------------------------------------------------------------
+
+ Display settings
+
+ SYNOPSIS
+
+ dmsetup table --target ioband
+
+ DESCRIPTION
+
+ Display the current table for the ioband device in a format. See
+ "dmsetup create" command for information on the table format.
+
+ EXAMPLE
+
+ The following output shows the current table of "ioband1."
+
+ # dmsetup table --target ioband
+ ioband: 0 32129937 ioband1 8:29 128 10 400 user weight \
+ 2048 :100 1000:80 2000:20
+
+
+ --------------------------------------------------------------------------
+
+ Display Statistics
+
+ SYNOPSIS
+
+ dmsetup status --target ioband
+
+ DESCRIPTION
+
+ Display the statistics of all the ioband devices whose target
+ type is "ioband."
+
+ The output format is as below. the first five columns shows:
+
+ * ioband device name
+
+ * logical start sector of the device (must be 0)
+
+ * device size in sectors
+
+ * target type (must be "ioband")
+
+ * device group ID
+
+ The remaining columns show the statistics of each ioband group
+ on the band device. Each group uses seven columns for its
+ statistics.
+
+ * ioband group ID (-1 means default)
+
+ * total read requests
+
+ * delayed read requests
+
+ * total read sectors
+
+ * total write requests
+
+ * delayed write requests
+
+ * total write sectors
+
+ EXAMPLE
+
+ The following output shows the statistics of two ioband devices.
+ Ioband2 only has the default ioband group and ioband1 has three
+ (default, 1001, 1002) ioband groups.
+
+ # dmsetup status
+ ioband2: 0 44371467 ioband 128 -1 143 90 424 122 78 352
+ ioband1: 0 44371467 ioband 128 -1 223 172 408 211 136 600 1001 \
+ 166 107 472 139 95 352 1002 211 146 520 210 147 504
+
+
+ --------------------------------------------------------------------------
+
+ Reset status counter
+
+ SYNOPSIS
+
+ dmsetup message IOBAND_DEVICE 0 reset
+
+ DESCRIPTION
+
+ Reset the statistics of ioband device IOBAND_DEVICE.
+
+ EXAMPLE
+
+ Reset the statistics of "ioband1."
+
+ # dmsetup message ioband1 0 reset
+
+
+ --------------------------------------------------------------------------
+
+Examples
+
+ Example #1: Bandwidth control on Partitions
+
+ This example describes how to control the bandwidth with disk
+ partitions. The following diagram illustrates the configuration of this
+ example. You may want to run a database on /dev/mapper/ioband1 and web
+ applications on /dev/mapper/ioband2.
+
+ /mnt1 /mnt2 mount points
+ | |
+ +-------------V------------+ +-------------V------------+
+ | /dev/mapper/ioband1 | | /dev/mapper/ioband2 | ioband devices
+ +--------------------------+ +--------------------------+
+ | default group | | default group | ioband groups
+ | (80) | | (40) | (weight)
+ +-------------|------------+ +-------------|------------+
+ | |
+ +-------------V-------------+--------------V------------+
+ | /dev/sda1 | /dev/sda2 | partitions
+ +---------------------------+---------------------------+
+
+
+ To setup the above configuration, follow these steps:
+
+ 1. Create ioband devices with the same device group ID and assign
+ weights of 80 and 40 to the default ioband groups respectively.
+
+ # echo "0 $(blockdev --getsize /dev/sda1) ioband /dev/sda1 1 0 0" \
+ "none weight 0 :80" | dmsetup create ioband1
+ # echo "0 $(blockdev --getsize /dev/sda2) ioband /dev/sda2 1 0 0" \
+ "none weight 0 :40" | dmsetup create ioband2
+
+
+ 2. Create filesystems on the ioband devices and mount them.
+
+ # mkfs.ext3 /dev/mapper/ioband1
+ # mount /dev/mapper/ioband1 /mnt1
+
+ # mkfs.ext3 /dev/mapper/ioband2
+ # mount /dev/mapper/ioband2 /mnt2
+
+
+ --------------------------------------------------------------------------
+
+ Example #2: Bandwidth control on Logical Volumes
+
+ This example is similar to the example #1 but it uses LVM logical
+ volumes instead of disk partitions. This example shows how to configure
+ ioband devices on two striped logical volumes.
+
+ /mnt1 /mnt2 mount points
+ | |
+ +-------------V------------+ +-------------V------------+
+ | /dev/mapper/ioband1 | | /dev/mapper/ioband2 | ioband devices
+ +--------------------------+ +--------------------------+
+ | default group | | default group | ioband groups
+ | (80) | | (40) | (weight)
+ +-------------|------------+ +-------------|------------+
+ | |
+ +-------------V------------+ +-------------V------------+
+ | /dev/mapper/lv0 | | /dev/mapper/lv1 | striped logical
+ | | | | volumes
+ +-------------------------------------------------------+
+ | vg0 | volume group
+ +-------------|----------------------------|------------+
+ | |
+ +-------------V------------+ +-------------V------------+
+ | /dev/sdb | | /dev/sdc | physical disks
+ +--------------------------+ +--------------------------+
+
+
+ To setup the above configuration, follow these steps:
+
+ 1. Initialize the partitions for use by LVM.
+
+ # pvcreate /dev/sdb
+ # pvcreate /dev/sdc
+
+
+ 2. Create a new volume group named "vg0" with /dev/sdb and /dev/sdc.
+
+ # vgcreate vg0 /dev/sdb /dev/sdc
+
+
+ 3. Create two logical volumes in "vg0." The volumes have to be striped.
+
+ # lvcreate -n lv0 -i 2 -I 64 vg0 -L 1024M
+ # lvcreate -n lv1 -i 2 -I 64 vg0 -L 1024M
+
+
+ The rest is the same as the example #1.
+
+ 4. Create ioband devices corresponding to each logical volume and
+ assign weights of 80 and 40 to the default ioband groups respectively.
+
+ # echo "0 $(blockdev --getsize /dev/mapper/vg0-lv0)" \
+ "ioband /dev/mapper/vg0-lv0 1 0 0 none weight 0 :80" | \
+ dmsetup create ioband1
+ # echo "0 $(blockdev --getsize /dev/mapper/vg0-lv1)" \
+ "ioband /dev/mapper/vg0-lv1 1 0 0 none weight 0 :40" | \
+ dmsetup create ioband2
+
+
+ 5. Create filesystems on the ioband devices and mount them.
+
+ # mkfs.ext3 /dev/mapper/ioband1
+ # mount /dev/mapper/ioband1 /mnt1
+
+ # mkfs.ext3 /dev/mapper/ioband2
+ # mount /dev/mapper/ioband2 /mnt2
+
+
+ --------------------------------------------------------------------------
+
+ Example #4: Bandwidth control on processes
+
+ This example describes how to control the bandwidth with groups of
+ processes. You may also want to run an additional application on the same
+ machine described in the example #1. This example shows how to add a new
+ ioband group for this application.
+
+ /mnt1 /mnt2 mount points
+ | |
+ +-------------V------------+ +-------------V------------+
+ | /dev/mapper/ioband1 | | /dev/mapper/ioband2 | ioband devices
+ +-------------+------------+ +-------------+------------+
+ | default | | user=1000 | default | ioband groups
+ | (80) | | (20) | (40) | (weight)
+ +-------------+------------+ +-------------+------------+
+ | |
+ +-------------V-------------+--------------V------------+
+ | /dev/sda1 | /dev/sda2 | partitions
+ +---------------------------+---------------------------+
+
+
+ The following shows to set up a new ioband group on the machine that is
+ already configured as the example #1. The application will have a weight
+ of 20 and run with user-id 1000 on /dev/mapper/ioband2.
+
+ 1. Set the type of ioband2 to "user."
+
+ # dmsetup message ioband2 0 type user.
+
+
+ 2. Create a new ioband group on ioband2.
+
+ # dmsetup message ioband2 0 attach 1000
+
+
+ 3. Assign weight of 10 to this newly created ioband group.
+
+ # dmsetup message ioband2 0 weight 1000:20
+
+
+ --------------------------------------------------------------------------
+
+ Example #3: Bandwidth control for Xen virtual block devices
+
+ This example describes how to control the bandwidth for Xen virtual
+ block devices. The following diagram illustrates the configuration of this
+ example.
+
+ Virtual Machine 1 Virtual Machine 2 virtual machines
+ | |
+ +-------------V------------+ +-------------V------------+
+ | /dev/xvda1 | | /dev/xvda1 | virtual block
+ +-------------|------------+ +-------------|------------+ devices
+ | |
+ +-------------V------------+ +-------------V------------+
+ | /dev/mapper/ioband1 | | /dev/mapper/ioband2 | ioband devices
+ +--------------------------+ +--------------------------+
+ | default group | | default group | ioband groups
+ | (80) | | (40) | (weight)
+ +-------------|------------+ +-------------|------------+
+ | |
+ +-------------V-------------+--------------V------------+
+ | /dev/sda1 | /dev/sda2 | partitions
+ +---------------------------+---------------------------+
+
+
+ The followings shows how to map ioband device "ioband1" and "ioband2" to
+ virtual block device "/dev/xvda1 on Virtual Machine 1" and "/dev/xvda1 on
+ Virtual Machine 2" respectively on the machine configured as the example
+ #1. Add the following lines to the configuration files that are referenced
+ when creating "Virtual Machine 1" and "Virtual Machine 2."
+
+ For "Virtual Machine 1"
+ disk = [ 'phy:/dev/mapper/ioband1,xvda,w' ]
+
+ For "Virtual Machine 2"
+ disk = [ 'phy:/dev/mapper/ioband2,xvda,w' ]
+
+
+ --------------------------------------------------------------------------
+
+ Example #4: Bandwidth control for Xen blktap devices
+
+ This example describes how to control the bandwidth for Xen virtual
+ block devices when Xen blktap devices are used. The following diagram
+ illustrates the configuration of this example.
+
+ Virtual Machine 1 Virtual Machine 2 virtual machines
+ | |
+ +-------------V------------+ +-------------V------------+
+ | /dev/xvda1 | | /dev/xvda1 | virtual block
+ +-------------|------------+ +-------------|------------+ devices
+ | |
+ +----------V----------+ +-----------V---------+
+ | tapdisk | | tapdisk | tapdisk daemons
+ | (15011) | | (15276) | (daemon's pid)
+ +----------|----------+ +-----------|---------+
+ | |
+ +-------------|----------------------------|------------+
+ | | /dev/mapper/ioband1 | | ioband device
+ | | mount on /vmdisk | |
+ +-------------V-------------+--------------V------------+
+ | group for PID=15011 | group for PID=15276 | ioband groups
+ | (80) | (40) | (weight)
+ +-------------|----------------------------|------------+
+ | |
+ +-------------|----------------------------|------------+
+ | +----------V----------+ +-----------V---------+ |
+ | | vm1.img | | vm2.img | | disk image files
+ | +---------------------+ +---------------------+ |
+ | /dev/sda1 | partition
+ +-------------------------------------------------------+
+
+
+ To setup the above configuration, follow these steps:
+
+ 1. Create an ioband device.
+
+ # echo "0 $(blockdev --getsize /dev/sda1) ioband /dev/sda1" \
+ "1 0 0 none weight 0 :100" | dmsetup create ioband1
+
+
+ 2. Add the following lines to the configuration files that are
+ referenced when creating "Virtual Machine 1" and "Virtual Machine 2."
+ Disk image files "/vmdisk/vm1.img" and "/vmdisk/vm2.img" will be used.
+
+ For "Virtual Machine 1"
+ disk = [ 'tap:aio:/vmdisk/vm1.img,xvda,w', ]
+
+ For "Virtual Machine 1"
+ disk = [ 'tap:aio:/vmdisk/vm2.img,xvda,w', ]
+
+
+ 3. Run the virtual machines.
+
+ # xm create vm1
+ # xm create vm2
+
+
+ 4. Find out the process IDs of the daemons which control the blktap
+ devices.
+
+ # lsof /vmdisk/disk[12].img
+ COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
+ tapdisk 15011 root 11u REG 253,0 2147483648 48961 /vmdisk/vm1.img
+ tapdisk 15276 root 13u REG 253,0 2147483648 48962 /vmdisk/vm2.img
+
+
+ 5. Create new ioband groups of pid 15011 and pid 15276, which are
+ process IDs of the tapdisks, and assign weight of 80 and 40 to the
+ groups respectively.
+
+ # dmsetup message ioband1 0 type pid
+ # dmsetup message ioband1 0 attach 15011
+ # dmsetup message ioband1 0 weight 15011:80
+ # dmsetup message ioband1 0 attach 15276
+ # dmsetup message ioband1 0 weight 15276:40
Index: linux-2.6.31/drivers/md/Kconfig
===================================================================
--- linux-2.6.31.orig/drivers/md/Kconfig
+++ linux-2.6.31/drivers/md/Kconfig
@@ -294,4 +294,17 @@ config DM_UEVENT
---help---
Generate udev events for DM events.
+config DM_IOBAND
+ tristate "I/O bandwidth control (EXPERIMENTAL)"
+ depends on BLK_DEV_DM && EXPERIMENTAL
+ ---help---
+ This device-mapper target allows to define how the
+ available bandwidth of a storage device should be
+ shared between processes, cgroups, the partitions or the LUNs.
+
+ Information on how to use dm-ioband is available in:
+ <file:Documentation/device-mapper/ioband.txt>.
+
+ If unsure, say N.
+
endif # MD
Index: linux-2.6.31/drivers/md/Makefile
===================================================================
--- linux-2.6.31.orig/drivers/md/Makefile
+++ linux-2.6.31/drivers/md/Makefile
@@ -8,6 +8,8 @@ dm-multipath-y += dm-path-selector.o dm-
dm-snapshot-y += dm-snap.o dm-exception-store.o dm-snap-transient.o \
dm-snap-persistent.o
dm-mirror-y += dm-raid1.o
+dm-ioband-y += dm-ioband-ctl.o dm-ioband-policy.o dm-ioband-rangebw.o \
+ dm-ioband-type.o
dm-log-userspace-y \
+= dm-log-userspace-base.o dm-log-userspace-transfer.o
md-mod-y += md.o bitmap.o
@@ -37,6 +39,7 @@ obj-$(CONFIG_BLK_DEV_MD) += md-mod.o
obj-$(CONFIG_BLK_DEV_DM) += dm-mod.o
obj-$(CONFIG_DM_CRYPT) += dm-crypt.o
obj-$(CONFIG_DM_DELAY) += dm-delay.o
+obj-$(CONFIG_DM_IOBAND) += dm-ioband.o
obj-$(CONFIG_DM_MULTIPATH) += dm-multipath.o dm-round-robin.o
obj-$(CONFIG_DM_MULTIPATH_QL) += dm-queue-length.o
obj-$(CONFIG_DM_MULTIPATH_ST) += dm-service-time.o
Index: linux-2.6.31/drivers/md/dm-ioband-ctl.c
===================================================================
--- /dev/null
+++ linux-2.6.31/drivers/md/dm-ioband-ctl.c
@@ -0,0 +1,1357 @@
+/*
+ * Copyright (C) 2008-2009 VA Linux Systems Japan K.K.
+ * Authors: Hirokazu Takahashi <[email protected]>
+ * Ryo Tsuruta <[email protected]>
+ *
+ * I/O bandwidth control
+ *
+ * Some blktrace messages were added by Alan D. Brunelle <[email protected]>
+ *
+ * This file is released under the GPL.
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/bio.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/rbtree.h>
+#include "dm.h"
+#include "md.h"
+#include "dm-ioband.h"
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/dm-ioband.h>
+
+static LIST_HEAD(ioband_device_list);
+/* lock up during configuration */
+static DEFINE_MUTEX(ioband_lock);
+
+static void suspend_ioband_device(struct ioband_device *, unsigned long, int);
+static void resume_ioband_device(struct ioband_device *);
+static void ioband_conduct(struct work_struct *);
+static void ioband_hold_bio(struct ioband_group *, struct bio *);
+static struct bio *ioband_pop_bio(struct ioband_group *);
+static int ioband_set_param(struct ioband_group *, const char *, const char *);
+static int ioband_group_attach(struct ioband_group *, int, int, const char *);
+static int ioband_group_type_select(struct ioband_group *, const char *);
+
+static void do_nothing(void) {}
+
+static int policy_init(struct ioband_device *dp, const char *name,
+ int argc, char **argv)
+{
+ const struct ioband_policy_type *p;
+ struct ioband_group *gp;
+ unsigned long flags;
+ int r;
+
+ for (p = dm_ioband_policy_type; p->p_name; p++) {
+ if (!strcmp(name, p->p_name))
+ break;
+ }
+ if (!p->p_name)
+ return -EINVAL;
+ /* do nothing if the same policy is already set */
+ if (dp->g_policy == p)
+ return 0;
+
+ spin_lock_irqsave(&dp->g_lock, flags);
+ suspend_ioband_device(dp, flags, 1);
+ list_for_each_entry(gp, &dp->g_groups, c_list)
+ dp->g_group_dtr(gp);
+
+ /* switch to the new policy */
+ dp->g_policy = p;
+ r = p->p_policy_init(dp, argc, argv);
+ if (!r) {
+ if (!dp->g_hold_bio)
+ dp->g_hold_bio = ioband_hold_bio;
+ if (!dp->g_pop_bio)
+ dp->g_pop_bio = ioband_pop_bio;
+
+ list_for_each_entry(gp, &dp->g_groups, c_list)
+ dp->g_group_ctr(gp, NULL);
+ }
+ resume_ioband_device(dp);
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return r;
+}
+
+static struct ioband_device *alloc_ioband_device(const char *name,
+ int io_throttle, int io_limit)
+{
+ struct ioband_device *dp, *new_dp;
+
+ new_dp = kzalloc(sizeof(struct ioband_device), GFP_KERNEL);
+ if (!new_dp)
+ return NULL;
+
+ /*
+ * Prepare its own workqueue as generic_make_request() may
+ * potentially block the workqueue when submitting BIOs.
+ */
+ new_dp->g_ioband_wq = create_workqueue("kioband");
+ if (!new_dp->g_ioband_wq) {
+ kfree(new_dp);
+ return NULL;
+ }
+
+ list_for_each_entry(dp, &ioband_device_list, g_list) {
+ if (!strcmp(dp->g_name, name)) {
+ dp->g_ref++;
+ destroy_workqueue(new_dp->g_ioband_wq);
+ kfree(new_dp);
+ return dp;
+ }
+ }
+
+ INIT_DELAYED_WORK(&new_dp->g_conductor, ioband_conduct);
+ INIT_LIST_HEAD(&new_dp->g_groups);
+ INIT_LIST_HEAD(&new_dp->g_list);
+ INIT_LIST_HEAD(&new_dp->g_root_groups);
+ spin_lock_init(&new_dp->g_lock);
+ bio_list_init(&new_dp->g_urgent_bios);
+ new_dp->g_io_throttle = io_throttle;
+ new_dp->g_io_limit = io_limit;
+ new_dp->g_issued[BLK_RW_SYNC] = 0;
+ new_dp->g_issued[BLK_RW_ASYNC] = 0;
+ new_dp->g_blocked = 0;
+ new_dp->g_ref = 1;
+ new_dp->g_flags = 0;
+ strlcpy(new_dp->g_name, name, sizeof(new_dp->g_name));
+ new_dp->g_policy = NULL;
+ new_dp->g_hold_bio = NULL;
+ new_dp->g_pop_bio = NULL;
+ init_waitqueue_head(&new_dp->g_waitq);
+ init_waitqueue_head(&new_dp->g_waitq_suspend);
+ init_waitqueue_head(&new_dp->g_waitq_flush);
+ list_add_tail(&new_dp->g_list, &ioband_device_list);
+ return new_dp;
+}
+
+static void release_ioband_device(struct ioband_device *dp)
+{
+ dp->g_ref--;
+ if (dp->g_ref > 0)
+ return;
+ list_del(&dp->g_list);
+ destroy_workqueue(dp->g_ioband_wq);
+ kfree(dp);
+}
+
+static int is_ioband_device_flushed(struct ioband_device *dp,
+ int wait_completion)
+{
+ struct ioband_group *gp;
+
+ if (wait_completion && nr_issued(dp) > 0)
+ return 0;
+ if (dp->g_blocked || waitqueue_active(&dp->g_waitq))
+ return 0;
+ list_for_each_entry(gp, &dp->g_groups, c_list)
+ if (waitqueue_active(&gp->c_waitq))
+ return 0;
+ return 1;
+}
+
+static void suspend_ioband_device(struct ioband_device *dp,
+ unsigned long flags, int wait_completion)
+{
+ struct ioband_group *gp;
+
+ /* block incoming bios */
+ set_device_suspended(dp);
+
+ /* wake up all blocked processes and go down all ioband groups */
+ wake_up_all(&dp->g_waitq);
+ list_for_each_entry(gp, &dp->g_groups, c_list) {
+ if (!is_group_down(gp)) {
+ set_group_down(gp);
+ set_group_need_up(gp);
+ }
+ wake_up_all(&gp->c_waitq);
+ }
+
+ /* flush the already mapped bios */
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ queue_delayed_work(dp->g_ioband_wq, &dp->g_conductor, 0);
+ flush_workqueue(dp->g_ioband_wq);
+
+ /* wait for all processes to wake up and bios to release */
+ spin_lock_irqsave(&dp->g_lock, flags);
+ wait_event_lock_irq(dp->g_waitq_flush,
+ is_ioband_device_flushed(dp, wait_completion),
+ dp->g_lock, do_nothing());
+}
+
+static void resume_ioband_device(struct ioband_device *dp)
+{
+ struct ioband_group *gp;
+
+ /* go up ioband groups */
+ list_for_each_entry(gp, &dp->g_groups, c_list) {
+ if (group_need_up(gp)) {
+ clear_group_need_up(gp);
+ clear_group_down(gp);
+ }
+ }
+
+ /* accept incoming bios */
+ wake_up_all(&dp->g_waitq_suspend);
+ clear_device_suspended(dp);
+}
+
+static struct ioband_group *ioband_group_find(struct ioband_group *head, int id)
+{
+ struct rb_node *node = head->c_group_root.rb_node;
+
+ while (node) {
+ struct ioband_group *p =
+ rb_entry(node, struct ioband_group, c_group_node);
+
+ if (p->c_id == id || id == IOBAND_ID_ANY)
+ return p;
+ node = (id < p->c_id) ? node->rb_left : node->rb_right;
+ }
+ return NULL;
+}
+
+static void ioband_group_add_node(struct rb_root *root, struct ioband_group *gp)
+{
+ struct rb_node **node = &root->rb_node, *parent = NULL;
+ struct ioband_group *p;
+
+ while (*node) {
+ p = rb_entry(*node, struct ioband_group, c_group_node);
+ parent = *node;
+ node = (gp->c_id < p->c_id) ?
+ &(*node)->rb_left : &(*node)->rb_right;
+ }
+
+ rb_link_node(&gp->c_group_node, parent, node);
+ rb_insert_color(&gp->c_group_node, root);
+}
+
+static int ioband_group_init(struct ioband_device *dp,
+ struct ioband_group *head,
+ struct ioband_group *parent,
+ struct ioband_group *gp,
+ int id, const char *param)
+{
+ unsigned long flags;
+ int r;
+
+ INIT_LIST_HEAD(&gp->c_list);
+ INIT_LIST_HEAD(&gp->c_sibling);
+ INIT_LIST_HEAD(&gp->c_children);
+ gp->c_parent = parent;
+ bio_list_init(&gp->c_blocked_bios);
+ bio_list_init(&gp->c_prio_bios);
+ gp->c_id = id; /* should be verified */
+ gp->c_blocked = 0;
+ gp->c_prio_blocked = 0;
+ memset(&gp->c_stats, 0, sizeof(gp->c_stats));
+ init_waitqueue_head(&gp->c_waitq);
+ gp->c_flags = 0;
+ gp->c_group_root = RB_ROOT;
+ gp->c_banddev = dp;
+
+ spin_lock_irqsave(&dp->g_lock, flags);
+ if (head && ioband_group_find(head, id)) {
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ DMWARN("%s: id=%d already exists.", __func__, id);
+ return -EEXIST;
+ }
+
+ list_add_tail(&gp->c_list, &dp->g_groups);
+
+ if (!parent)
+ list_add_tail(&gp->c_sibling, &dp->g_root_groups);
+ else
+ list_add_tail(&gp->c_sibling, &parent->c_children);
+
+ r = dp->g_group_ctr(gp, param);
+ if (r) {
+ list_del(&gp->c_list);
+ list_del(&gp->c_sibling);
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return r;
+ }
+
+ if (head) {
+ ioband_group_add_node(&head->c_group_root, gp);
+ gp->c_dev = head->c_dev;
+ gp->c_target = head->c_target;
+ }
+
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return 0;
+}
+
+static void ioband_group_release(struct ioband_group *head,
+ struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+
+ list_del(&gp->c_list);
+ list_del(&gp->c_sibling);
+ if (head)
+ rb_erase(&gp->c_group_node, &head->c_group_root);
+ dp->g_group_dtr(gp);
+ kfree(gp);
+}
+
+static void ioband_group_destroy_all(struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ struct ioband_group *p;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dp->g_lock, flags);
+ while ((p = ioband_group_find(gp, IOBAND_ID_ANY)))
+ ioband_group_release(gp, p);
+ ioband_group_release(NULL, gp);
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+}
+
+static void ioband_group_stop_all(struct ioband_group *head, int suspend)
+{
+ struct ioband_device *dp = head->c_banddev;
+ struct ioband_group *p;
+ struct rb_node *node;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dp->g_lock, flags);
+ for (node = rb_first(&head->c_group_root); node; node = rb_next(node)) {
+ p = rb_entry(node, struct ioband_group, c_group_node);
+ set_group_down(p);
+ if (suspend)
+ set_group_suspended(p);
+ }
+ set_group_down(head);
+ if (suspend)
+ set_group_suspended(head);
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ queue_delayed_work(dp->g_ioband_wq, &dp->g_conductor, 0);
+ flush_workqueue(dp->g_ioband_wq);
+}
+
+static void ioband_group_resume_all(struct ioband_group *head)
+{
+ struct ioband_device *dp = head->c_banddev;
+ struct ioband_group *p;
+ struct rb_node *node;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dp->g_lock, flags);
+ for (node = rb_first(&head->c_group_root); node; node = rb_next(node)) {
+ p = rb_entry(node, struct ioband_group, c_group_node);
+ clear_group_down(p);
+ clear_group_suspended(p);
+ }
+ clear_group_down(head);
+ clear_group_suspended(head);
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+}
+
+static int parse_group_param(const char *param, long *id, char const **value)
+{
+ char *s, *endp;
+ long n;
+
+ s = strpbrk(param, POLICY_PARAM_DELIM);
+ if (!s) {
+ *id = IOBAND_ID_ANY;
+ *value = param;
+ return 0;
+ }
+
+ n = simple_strtol(param, &endp, 0);
+ if (endp != s)
+ return -EINVAL;
+
+ *id = (endp == param) ? IOBAND_ID_ANY : n;
+ *value = endp + 1;
+ return 0;
+}
+
+/*
+ * Create a new band device:
+ * parameters: <device> <device-group-id> <io_throttle> <io_limit>
+ * <type> <policy> <policy-param...> <group-id:group-param...>
+ */
+static int ioband_ctr(struct dm_target *ti, unsigned argc, char **argv)
+{
+ struct ioband_group *gp;
+ struct ioband_device *dp;
+ struct dm_dev *dev;
+ int io_throttle;
+ int io_limit;
+ int i, r, start;
+ long val, id;
+ const char *param;
+ char *s;
+
+ if (argc < POLICY_PARAM_START) {
+ ti->error = "Requires " __stringify(POLICY_PARAM_START)
+ " or more arguments";
+ return -EINVAL;
+ }
+
+ if (strlen(argv[1]) > IOBAND_NAME_MAX) {
+ ti->error = "Ioband device name is too long";
+ return -EINVAL;
+ }
+
+ r = strict_strtol(argv[2], 0, &val);
+ if (r || val < 0 || val > SHORT_MAX) {
+ ti->error = "Invalid io_throttle";
+ return -EINVAL;
+ }
+ io_throttle = (val == 0) ? DEFAULT_IO_THROTTLE : val;
+
+ r = strict_strtol(argv[3], 0, &val);
+ if (r || val < 0 || val > SHORT_MAX) {
+ ti->error = "Invalid io_limit";
+ return -EINVAL;
+ }
+ io_limit = val;
+
+ r = dm_get_device(ti, argv[0], 0, ti->len,
+ dm_table_get_mode(ti->table), &dev);
+ if (r) {
+ ti->error = "Device lookup failed";
+ return r;
+ }
+
+ if (io_limit == 0) {
+ struct request_queue *q;
+
+ q = bdev_get_queue(dev->bdev);
+ if (!q) {
+ ti->error = "Can't get queue size";
+ r = -ENXIO;
+ goto release_dm_device;
+ }
+ /*
+ * The block layer accepts I/O requests up to 50% over
+ * nr_requests when the requests are issued from a
+ * "batcher" process.
+ */
+ io_limit = (3 * q->nr_requests / 2);
+ }
+
+ if (io_limit < io_throttle)
+ io_limit = io_throttle;
+
+ mutex_lock(&ioband_lock);
+ dp = alloc_ioband_device(argv[1], io_throttle, io_limit);
+ if (!dp) {
+ ti->error = "Cannot create ioband device";
+ r = -EINVAL;
+ mutex_unlock(&ioband_lock);
+ goto release_dm_device;
+ }
+
+ r = policy_init(dp, argv[POLICY_PARAM_START - 1],
+ argc - POLICY_PARAM_START, &argv[POLICY_PARAM_START]);
+ if (r) {
+ ti->error = "Invalid policy parameter";
+ goto release_ioband_device;
+ }
+
+ gp = kzalloc(sizeof(struct ioband_group), GFP_KERNEL);
+ if (!gp) {
+ ti->error = "Cannot allocate memory for ioband group";
+ r = -ENOMEM;
+ goto release_ioband_device;
+ }
+
+ ti->num_flush_requests = 1;
+ ti->private = gp;
+ gp->c_target = ti;
+ gp->c_dev = dev;
+
+ /* Find a default group parameter */
+ for (start = POLICY_PARAM_START; start < argc; start++) {
+ s = strpbrk(argv[start], POLICY_PARAM_DELIM);
+ if (s == argv[start])
+ break;
+ }
+ param = (start < argc) ? &argv[start][1] : NULL;
+
+ /* Create a default ioband group */
+ r = ioband_group_init(dp, NULL, NULL, gp, IOBAND_ID_ANY, param);
+ if (r) {
+ kfree(gp);
+ ti->error = "Cannot create default ioband group";
+ goto release_ioband_device;
+ }
+
+ r = ioband_group_type_select(gp, argv[4]);
+ if (r) {
+ ti->error = "Cannot set ioband group type";
+ goto release_ioband_group;
+ }
+
+ /* Create sub ioband groups */
+ for (i = start + 1; i < argc; i++) {
+ r = parse_group_param(argv[i], &id, ¶m);
+ if (r) {
+ ti->error = "Invalid ioband group parameter";
+ goto release_ioband_group;
+ }
+ r = ioband_group_attach(gp, 0, id, param);
+ if (r) {
+ ti->error = "Cannot create ioband group";
+ goto release_ioband_group;
+ }
+ }
+ mutex_unlock(&ioband_lock);
+ return 0;
+
+release_ioband_group:
+ ioband_group_destroy_all(gp);
+release_ioband_device:
+ release_ioband_device(dp);
+ mutex_unlock(&ioband_lock);
+release_dm_device:
+ dm_put_device(ti, dev);
+ return r;
+}
+
+static void ioband_dtr(struct dm_target *ti)
+{
+ struct ioband_group *gp = ti->private;
+ struct ioband_device *dp = gp->c_banddev;
+ struct dm_dev *dev = gp->c_dev;
+
+ mutex_lock(&ioband_lock);
+
+ ioband_group_stop_all(gp, 0);
+ cancel_delayed_work_sync(&dp->g_conductor);
+ ioband_group_destroy_all(gp);
+
+ release_ioband_device(dp);
+ mutex_unlock(&ioband_lock);
+
+ dm_put_device(ti, dev);
+}
+
+static void ioband_hold_bio(struct ioband_group *gp, struct bio *bio)
+{
+ /* Todo: The list should be split into a sync list and an async list */
+ bio_list_add(&gp->c_blocked_bios, bio);
+}
+
+static struct bio *ioband_pop_bio(struct ioband_group *gp)
+{
+ return bio_list_pop(&gp->c_blocked_bios);
+}
+
+static int is_urgent_bio(struct bio *bio)
+{
+ struct page *page = bio_iovec_idx(bio, 0)->bv_page;
+ /*
+ * ToDo: A new flag should be added to struct bio, which indicates
+ * it contains urgent I/O requests.
+ */
+ if (!PageReclaim(page))
+ return 0;
+ if (PageSwapCache(page))
+ return 2;
+ return 1;
+}
+
+static inline int device_should_block(struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+
+ if (is_group_down(gp))
+ return 0;
+ if (is_device_blocked(dp))
+ return 1;
+ if (dp->g_blocked >= dp->g_io_limit * 2) {
+ set_device_blocked(dp);
+ return 1;
+ }
+ return 0;
+}
+
+static inline int group_should_block(struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+
+ if (is_group_down(gp))
+ return 0;
+ if (is_group_blocked(gp))
+ return 1;
+ if (dp->g_should_block(gp)) {
+ set_group_blocked(gp);
+ return 1;
+ }
+ return 0;
+}
+
+static void prevent_burst_bios(struct ioband_group *gp, struct bio *bio)
+{
+ struct ioband_device *dp = gp->c_banddev;
+
+ if (current->flags & PF_KTHREAD || is_urgent_bio(bio)) {
+ /*
+ * Kernel threads shouldn't be blocked easily since each of
+ * them may handle BIOs for several groups on several
+ * partitions.
+ */
+ wait_event_lock_irq(dp->g_waitq, !device_should_block(gp),
+ dp->g_lock, do_nothing());
+ } else {
+ wait_event_lock_irq(gp->c_waitq, !group_should_block(gp),
+ dp->g_lock, do_nothing());
+ }
+}
+
+static inline int should_pushback_bio(struct ioband_group *gp)
+{
+ return is_group_suspended(gp) && dm_noflush_suspending(gp->c_target);
+}
+
+static inline bool bio_is_sync(struct bio *bio)
+{
+ /* Must be the same condition as rw_is_sync() in blkdev.h */
+ return !bio_data_dir(bio) || bio_sync(bio);
+}
+
+static inline int prepare_to_issue(struct ioband_group *gp, struct bio *bio)
+{
+ struct ioband_device *dp = gp->c_banddev;
+
+ dp->g_issued[bio_is_sync(bio)]++;
+ return dp->g_prepare_bio(gp, bio, 0);
+}
+
+static inline int room_for_bio(struct ioband_device *dp)
+{
+ return dp->g_issued[BLK_RW_SYNC] < dp->g_io_limit
+ || dp->g_issued[BLK_RW_ASYNC] < dp->g_io_limit;
+}
+
+static void hold_bio(struct ioband_group *gp, struct bio *bio)
+{
+ struct ioband_device *dp = gp->c_banddev;
+
+ dp->g_blocked++;
+ if (is_urgent_bio(bio)) {
+ dp->g_prepare_bio(gp, bio, IOBAND_URGENT);
+ bio_list_add(&dp->g_urgent_bios, bio);
+ trace_ioband_hold_urgent_bio(gp, bio);
+ } else {
+ gp->c_blocked++;
+ dp->g_hold_bio(gp, bio);
+ trace_ioband_hold_bio(gp, bio);
+ }
+}
+
+static inline int room_for_bio_sync(struct ioband_device *dp, int sync)
+{
+ return dp->g_issued[sync] < dp->g_io_limit;
+}
+
+static void push_prio_bio(struct ioband_group *gp, struct bio *bio, int sync)
+{
+ if (bio_list_empty(&gp->c_prio_bios))
+ set_prio_queue(gp, sync);
+ bio_list_add(&gp->c_prio_bios, bio);
+ gp->c_prio_blocked++;
+}
+
+static struct bio *pop_prio_bio(struct ioband_group *gp)
+{
+ struct bio *bio = bio_list_pop(&gp->c_prio_bios);
+
+ if (bio_list_empty(&gp->c_prio_bios))
+ clear_prio_queue(gp);
+
+ if (bio)
+ gp->c_prio_blocked--;
+ return bio;
+}
+
+static int make_issue_list(struct ioband_group *gp, struct bio *bio,
+ struct bio_list *issue_list,
+ struct bio_list *pushback_list)
+{
+ struct ioband_device *dp = gp->c_banddev;
+
+ dp->g_blocked--;
+ gp->c_blocked--;
+ if (!gp->c_blocked && is_group_blocked(gp)) {
+ clear_group_blocked(gp);
+ wake_up_all(&gp->c_waitq);
+ }
+ if (should_pushback_bio(gp)) {
+ bio_list_add(pushback_list, bio);
+ trace_ioband_make_pback_list(gp, bio);
+ } else {
+ int rw = bio_data_dir(bio);
+
+ gp->c_stats.sectors[rw] += bio_sectors(bio);
+ gp->c_stats.ios[rw]++;
+ bio_list_add(issue_list, bio);
+ trace_ioband_make_issue_list(gp, bio);
+ }
+ return prepare_to_issue(gp, bio);
+}
+
+static void release_urgent_bios(struct ioband_device *dp,
+ struct bio_list *issue_list,
+ struct bio_list *pushback_list)
+{
+ struct bio *bio;
+
+ if (bio_list_empty(&dp->g_urgent_bios))
+ return;
+ while (room_for_bio_sync(dp, BLK_RW_ASYNC)) {
+ bio = bio_list_pop(&dp->g_urgent_bios);
+ if (!bio)
+ return;
+ dp->g_blocked--;
+ dp->g_issued[bio_is_sync(bio)]++;
+ bio_list_add(issue_list, bio);
+ trace_ioband_release_urgent_bios(dp, bio);
+ }
+}
+
+static int release_prio_bios(struct ioband_group *gp,
+ struct bio_list *issue_list,
+ struct bio_list *pushback_list)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ struct bio *bio;
+ int sync;
+ int ret;
+
+ if (bio_list_empty(&gp->c_prio_bios))
+ return R_OK;
+ sync = prio_queue_sync(gp);
+ while (gp->c_prio_blocked) {
+ if (!dp->g_can_submit(gp))
+ return R_BLOCK;
+ if (!room_for_bio_sync(dp, sync))
+ return R_OK;
+ bio = pop_prio_bio(gp);
+ if (!bio)
+ return R_OK;
+ ret = make_issue_list(gp, bio, issue_list, pushback_list);
+ if (ret)
+ return ret;
+ }
+ return R_OK;
+}
+
+static int release_norm_bios(struct ioband_group *gp,
+ struct bio_list *issue_list,
+ struct bio_list *pushback_list)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ struct bio *bio;
+ int sync, ret;
+
+ while (gp->c_blocked - gp->c_prio_blocked) {
+ if (!dp->g_can_submit(gp))
+ return R_BLOCK;
+ if (!room_for_bio(dp))
+ return R_OK;
+ bio = dp->g_pop_bio(gp);
+ if (!bio)
+ return R_OK;
+
+ sync = bio_is_sync(bio);
+ if (!room_for_bio_sync(dp, sync)) {
+ push_prio_bio(gp, bio, sync);
+ continue;
+ }
+ ret = make_issue_list(gp, bio, issue_list, pushback_list);
+ if (ret)
+ return ret;
+ }
+ return R_OK;
+}
+
+static inline int release_bios(struct ioband_group *gp,
+ struct bio_list *issue_list,
+ struct bio_list *pushback_list)
+{
+ int ret = release_prio_bios(gp, issue_list, pushback_list);
+ if (ret)
+ return ret;
+ return release_norm_bios(gp, issue_list, pushback_list);
+}
+
+static struct ioband_group *ioband_group_get(struct ioband_group *head,
+ struct bio *bio)
+{
+ struct ioband_group *gp;
+
+ if (!head->c_type->t_getid)
+ return head;
+
+ gp = ioband_group_find(head, head->c_type->t_getid(bio));
+
+ if (!gp)
+ gp = head;
+ return gp;
+}
+
+/*
+ * Start to control the bandwidth once the number of uncompleted BIOs
+ * exceeds the value of "io_throttle".
+ */
+static int ioband_map(struct dm_target *ti, struct bio *bio,
+ union map_info *map_context)
+{
+ struct ioband_group *gp = ti->private;
+ struct ioband_device *dp = gp->c_banddev;
+ unsigned long flags;
+ int rw;
+
+ spin_lock_irqsave(&dp->g_lock, flags);
+
+ /*
+ * The device is suspended while some of the ioband device
+ * configurations are being changed.
+ */
+ if (is_device_suspended(dp))
+ wait_event_lock_irq(dp->g_waitq_suspend,
+ !is_device_suspended(dp), dp->g_lock,
+ do_nothing());
+
+ gp = ioband_group_get(gp, bio);
+ prevent_burst_bios(gp, bio);
+ if (should_pushback_bio(gp)) {
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return DM_MAPIO_REQUEUE;
+ }
+
+ bio->bi_bdev = gp->c_dev->bdev;
+ if (bio_sectors(bio))
+ bio->bi_sector -= ti->begin;
+
+ if (!gp->c_blocked && room_for_bio_sync(dp, bio_is_sync(bio))) {
+ if (dp->g_can_submit(gp)) {
+ prepare_to_issue(gp, bio);
+ rw = bio_data_dir(bio);
+ gp->c_stats.sectors[rw] += bio_sectors(bio);
+ gp->c_stats.ios[rw]++;
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return DM_MAPIO_REMAPPED;
+ } else if (!dp->g_blocked && nr_issued(dp) == 0) {
+ DMDEBUG("%s: token expired gp:%p", __func__, gp);
+ queue_delayed_work(dp->g_ioband_wq,
+ &dp->g_conductor, 1);
+ }
+ }
+ hold_bio(gp, bio);
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+
+ return DM_MAPIO_SUBMITTED;
+}
+
+/*
+ * Select the best group to resubmit its BIOs.
+ */
+static struct ioband_group *choose_best_group(struct ioband_device *dp)
+{
+ struct ioband_group *gp;
+ struct ioband_group *best = NULL;
+ int highest = 0;
+ int pri;
+
+ /* Todo: The algorithm should be optimized.
+ * It would be better to use rbtree.
+ */
+ list_for_each_entry(gp, &dp->g_groups, c_list) {
+ if (!gp->c_blocked || !room_for_bio(dp))
+ continue;
+ if (gp->c_blocked == gp->c_prio_blocked &&
+ !room_for_bio_sync(dp, prio_queue_sync(gp))) {
+ continue;
+ }
+ pri = dp->g_can_submit(gp);
+ if (pri > highest) {
+ highest = pri;
+ best = gp;
+ }
+ }
+
+ return best;
+}
+
+/*
+ * This function is called right after it becomes able to resubmit BIOs.
+ * It selects the best BIOs and passes them to the underlying layer.
+ */
+static void ioband_conduct(struct work_struct *work)
+{
+ struct ioband_device *dp =
+ container_of(work, struct ioband_device, g_conductor.work);
+ struct ioband_group *gp = NULL;
+ struct bio *bio;
+ unsigned long flags;
+ struct bio_list issue_list, pushback_list;
+
+ bio_list_init(&issue_list);
+ bio_list_init(&pushback_list);
+
+ spin_lock_irqsave(&dp->g_lock, flags);
+ release_urgent_bios(dp, &issue_list, &pushback_list);
+ if (dp->g_blocked) {
+ gp = choose_best_group(dp);
+ if (gp &&
+ release_bios(gp, &issue_list, &pushback_list) == R_YIELD)
+ queue_delayed_work(dp->g_ioband_wq,
+ &dp->g_conductor, 0);
+ }
+
+ if (is_device_blocked(dp) && dp->g_blocked < dp->g_io_limit * 2) {
+ clear_device_blocked(dp);
+ wake_up_all(&dp->g_waitq);
+ }
+
+ if (dp->g_blocked &&
+ room_for_bio_sync(dp, BLK_RW_SYNC) &&
+ room_for_bio_sync(dp, BLK_RW_ASYNC) &&
+ bio_list_empty(&issue_list) && bio_list_empty(&pushback_list) &&
+ dp->g_restart_bios(dp)) {
+ DMDEBUG("%s: token expired dp:%p issued(%d,%d) g_blocked(%d)",
+ __func__, dp,
+ dp->g_issued[BLK_RW_SYNC], dp->g_issued[BLK_RW_ASYNC],
+ dp->g_blocked);
+ queue_delayed_work(dp->g_ioband_wq, &dp->g_conductor, 0);
+ }
+
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+
+ while ((bio = bio_list_pop(&issue_list))) {
+ trace_ioband_make_request(dp, bio);
+ generic_make_request(bio);
+ }
+
+ while ((bio = bio_list_pop(&pushback_list))) {
+ trace_ioband_pushback_bio(dp, bio);
+ bio_endio(bio, -EIO);
+ }
+}
+
+static int ioband_end_io(struct dm_target *ti, struct bio *bio,
+ int error, union map_info *map_context)
+{
+ struct ioband_group *gp = ti->private;
+ struct ioband_device *dp = gp->c_banddev;
+ unsigned long flags;
+ int r = error;
+
+ /*
+ * XXX: A new error code for device mapper devices should be used
+ * rather than EIO.
+ */
+ if (error == -EIO && should_pushback_bio(gp)) {
+ /* This ioband device is suspending */
+ r = DM_ENDIO_REQUEUE;
+ }
+ /*
+ * Todo: The algorithm should be optimized to eliminate the spinlock.
+ */
+ spin_lock_irqsave(&dp->g_lock, flags);
+ dp->g_issued[bio_is_sync(bio)]--;
+
+ /*
+ * Todo: It would be better to introduce high/low water marks here
+ * not to kick the workqueues so often.
+ */
+ if (dp->g_blocked)
+ queue_delayed_work(dp->g_ioband_wq, &dp->g_conductor, 0);
+ else if (is_device_suspended(dp) && nr_issued(dp) == 0)
+ wake_up_all(&dp->g_waitq_flush);
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return r;
+}
+
+static void ioband_presuspend(struct dm_target *ti)
+{
+ struct ioband_group *gp = ti->private;
+
+ ioband_group_stop_all(gp, 1);
+}
+
+static void ioband_resume(struct dm_target *ti)
+{
+ struct ioband_group *gp = ti->private;
+
+ ioband_group_resume_all(gp);
+}
+
+static void ioband_group_status(struct ioband_group *gp, int *szp,
+ char *result, unsigned maxlen)
+{
+ int sz = *szp; /* used in DMEMIT() */
+ struct disk_stats *st = &gp->c_stats;
+
+ DMEMIT(" %d %lu %lu %lu %lu %lu %lu %lu %lu %d %lu %lu",
+ gp->c_id,
+ st->ios[0], st->merges[0], st->sectors[0], st->ticks[0],
+ st->ios[1], st->merges[1], st->sectors[1], st->ticks[1],
+ gp->c_blocked, st->io_ticks, st->time_in_queue);
+ *szp = sz;
+}
+
+static int ioband_status(struct dm_target *ti, status_type_t type,
+ char *result, unsigned maxlen)
+{
+ struct ioband_group *gp = ti->private, *p;
+ struct ioband_device *dp = gp->c_banddev;
+ struct rb_node *node;
+ int sz = 0; /* used in DMEMIT() */
+ unsigned long flags;
+
+ spin_lock_irqsave(&dp->g_lock, flags);
+
+ switch (type) {
+ case STATUSTYPE_INFO:
+ DMEMIT("%s", dp->g_name);
+ ioband_group_status(gp, &sz, result, maxlen);
+ for (node = rb_first(&gp->c_group_root); node;
+ node = rb_next(node)) {
+ p = rb_entry(node, struct ioband_group, c_group_node);
+ ioband_group_status(p, &sz, result, maxlen);
+ }
+ break;
+
+ case STATUSTYPE_TABLE:
+ DMEMIT("%s %s %d %d %s %s",
+ gp->c_dev->name, dp->g_name,
+ dp->g_io_throttle, dp->g_io_limit,
+ gp->c_type->t_name, dp->g_policy->p_name);
+ dp->g_show(gp, &sz, result, maxlen);
+ break;
+ }
+
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return 0;
+}
+
+static int ioband_group_type_select(struct ioband_group *gp, const char *name)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ const struct ioband_group_type *t;
+ unsigned long flags;
+
+ for (t = dm_ioband_group_type; (t->t_name); t++) {
+ if (!strcmp(name, t->t_name))
+ break;
+ }
+ if (!t->t_name) {
+ DMWARN("%s: %s isn't supported.", __func__, name);
+ return -EINVAL;
+ }
+ spin_lock_irqsave(&dp->g_lock, flags);
+ if (!RB_EMPTY_ROOT(&gp->c_group_root)) {
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return -EBUSY;
+ }
+ gp->c_type = t;
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+
+ return 0;
+}
+
+static int ioband_set_param(struct ioband_group *gp,
+ const char *cmd, const char *value)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ const char *val_str;
+ long id;
+ unsigned long flags;
+ int r;
+
+ r = parse_group_param(value, &id, &val_str);
+ if (r)
+ return r;
+
+ spin_lock_irqsave(&dp->g_lock, flags);
+ if (id != IOBAND_ID_ANY) {
+ gp = ioband_group_find(gp, id);
+ if (!gp) {
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ DMWARN("%s: id=%ld not found.", __func__, id);
+ return -EINVAL;
+ }
+ }
+ r = dp->g_set_param(gp, cmd, val_str);
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return r;
+}
+
+static int ioband_group_attach(struct ioband_group *head, int parent_id,
+ int id, const char *param)
+{
+ struct ioband_device *dp = head->c_banddev;
+ struct ioband_group *parent, *gp;
+ int r;
+
+ if (id < 0) {
+ DMWARN("%s: invalid id:%d", __func__, id);
+ return -EINVAL;
+ }
+ if (!head->c_type->t_getid) {
+ DMWARN("%s: no ioband group type is specified", __func__);
+ return -EINVAL;
+ }
+
+ /* Determines a parent ioband group */
+ switch (parent_id) {
+ case 0:
+ /* Non-hierarchical configuration */
+ parent = NULL;
+ break;
+ case 1:
+ /* The root of a tree, the parent is a default ioband group */
+ parent = head;
+ break;
+ default:
+ /* The node in a tree. */
+ parent = ioband_group_find(head, parent_id);
+ if (!parent) {
+ DMWARN("%s: parent group is not configured", __func__);
+ return -EINVAL;
+ }
+ break;
+ }
+
+ gp = kzalloc(sizeof(struct ioband_group), GFP_KERNEL);
+ if (!gp)
+ return -ENOMEM;
+
+ r = ioband_group_init(dp, head, parent, gp, id, param);
+ if (r < 0) {
+ kfree(gp);
+ return r;
+ }
+ return 0;
+}
+
+static int ioband_group_detach(struct ioband_group *head, int id)
+{
+ struct ioband_device *dp = head->c_banddev;
+ struct ioband_group *gp;
+ unsigned long flags;
+ int r = 0;
+
+ if (id < 0) {
+ DMWARN("%s: invalid id:%d", __func__, id);
+ return -EINVAL;
+ }
+ spin_lock_irqsave(&dp->g_lock, flags);
+ gp = ioband_group_find(head, id);
+ if (!gp) {
+ DMWARN("%s: invalid id:%d", __func__, id);
+ r = -EINVAL;
+ goto out;
+ }
+
+ if (!list_empty(&gp->c_children)) {
+ DMWARN("%s: group has children", __func__);
+ r = -EBUSY;
+ goto out;
+ }
+
+ /*
+ * Todo: Calling suspend_ioband_device() before releasing the
+ * ioband group has a large overhead. Need improvement.
+ */
+ suspend_ioband_device(dp, flags, 0);
+ ioband_group_release(head, gp);
+ resume_ioband_device(dp);
+out:
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return r;
+}
+
+/*
+ * Message parameters:
+ * "policy" <name>
+ * ex)
+ * "policy" "weight"
+ * "type" "none"|"pid"|"pgrp"|"node"|"cpuset"|"cgroup"|"user"|"gid"
+ * "io_throttle" <value>
+ * "io_limit" <value>
+ * "attach" <group id>
+ * "detach" <group id>
+ * "any-command" <group id>:<value>
+ * ex)
+ * "weight" 0:<value>
+ * "token" 24:<value>
+ */
+static int __ioband_message(struct dm_target *ti, unsigned argc, char **argv)
+{
+ struct ioband_group *gp = ti->private, *p;
+ struct ioband_device *dp = gp->c_banddev;
+ struct rb_node *node;
+ long val;
+ int r = 0;
+ unsigned long flags;
+
+ if (argc == 1 && !strcmp(argv[0], "reset")) {
+ spin_lock_irqsave(&dp->g_lock, flags);
+ memset(&gp->c_stats, 0, sizeof(gp->c_stats));
+ for (node = rb_first(&gp->c_group_root); node;
+ node = rb_next(node)) {
+ p = rb_entry(node, struct ioband_group, c_group_node);
+ memset(&p->c_stats, 0, sizeof(p->c_stats));
+ }
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return 0;
+ }
+
+ if (argc != 2) {
+ DMWARN("Unrecognised band message received.");
+ return -EINVAL;
+ }
+ if (!strcmp(argv[0], "io_throttle")) {
+ r = strict_strtol(argv[1], 0, &val);
+ if (r || val < 0 || val > SHORT_MAX)
+ return -EINVAL;
+ if (val == 0)
+ val = DEFAULT_IO_THROTTLE;
+ spin_lock_irqsave(&dp->g_lock, flags);
+ if (val > dp->g_io_limit) {
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return -EINVAL;
+ }
+ dp->g_io_throttle = val;
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ ioband_set_param(gp, argv[0], argv[1]);
+ return 0;
+ } else if (!strcmp(argv[0], "io_limit")) {
+ r = strict_strtol(argv[1], 0, &val);
+ if (r || val < 0 || val > SHORT_MAX)
+ return -EINVAL;
+ spin_lock_irqsave(&dp->g_lock, flags);
+ if (val == 0) {
+ struct request_queue *q;
+
+ q = bdev_get_queue(gp->c_dev->bdev);
+ if (!q) {
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return -ENXIO;
+ }
+ /*
+ * The block layer accepts I/O requests up to
+ * 50% over nr_requests when the requests are
+ * issued from a "batcher" process.
+ */
+ val = (3 * q->nr_requests / 2);
+ }
+ if (val < dp->g_io_throttle) {
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ return -EINVAL;
+ }
+ dp->g_io_limit = val;
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ ioband_set_param(gp, argv[0], argv[1]);
+ return 0;
+ } else if (!strcmp(argv[0], "type")) {
+ return ioband_group_type_select(gp, argv[1]);
+ } else if (!strcmp(argv[0], "attach")) {
+ r = strict_strtol(argv[1], 0, &val);
+ if (r)
+ return r;
+ return ioband_group_attach(gp, 0, val, NULL);
+ } else if (!strcmp(argv[0], "detach")) {
+ r = strict_strtol(argv[1], 0, &val);
+ if (r)
+ return r;
+ return ioband_group_detach(gp, val);
+ } else if (!strcmp(argv[0], "policy")) {
+ r = policy_init(dp, argv[1], 0, &argv[2]);
+ return r;
+ } else {
+ /* message anycommand <group-id>:<value> */
+ r = ioband_set_param(gp, argv[0], argv[1]);
+ if (r < 0)
+ DMWARN("Unrecognised band message received.");
+ return r;
+ }
+ return 0;
+}
+
+static int ioband_message(struct dm_target *ti, unsigned argc, char **argv)
+{
+ int r;
+
+ mutex_lock(&ioband_lock);
+ r = __ioband_message(ti, argc, argv);
+ mutex_unlock(&ioband_lock);
+ return r;
+}
+
+static int ioband_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
+ struct bio_vec *biovec, int max_size)
+{
+ struct ioband_group *gp = ti->private;
+ struct request_queue *q = bdev_get_queue(gp->c_dev->bdev);
+
+ if (!q->merge_bvec_fn)
+ return max_size;
+
+ bvm->bi_bdev = gp->c_dev->bdev;
+ bvm->bi_sector -= ti->begin;
+
+ return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
+}
+
+static int ioband_iterate_devices(struct dm_target *ti,
+ iterate_devices_callout_fn fn, void *data)
+{
+ struct ioband_group *gp = ti->private;
+
+ return fn(ti, gp->c_dev, 0, ti->len, data);
+}
+
+static struct target_type ioband_target = {
+ .name = "ioband",
+ .module = THIS_MODULE,
+ .version = {1, 13, 0},
+ .ctr = ioband_ctr,
+ .dtr = ioband_dtr,
+ .map = ioband_map,
+ .end_io = ioband_end_io,
+ .presuspend = ioband_presuspend,
+ .resume = ioband_resume,
+ .status = ioband_status,
+ .message = ioband_message,
+ .merge = ioband_merge,
+ .iterate_devices = ioband_iterate_devices,
+};
+
+static int __init dm_ioband_init(void)
+{
+ int r;
+
+ r = dm_register_target(&ioband_target);
+ if (r < 0)
+ DMERR("register failed %d", r);
+ return r;
+}
+
+static void __exit dm_ioband_exit(void)
+{
+ dm_unregister_target(&ioband_target);
+}
+
+module_init(dm_ioband_init);
+module_exit(dm_ioband_exit);
+
+MODULE_DESCRIPTION(DM_NAME " I/O bandwidth control");
+MODULE_AUTHOR("Hirokazu Takahashi, Ryo Tsuruta, Dong-Jae Kang");
+MODULE_LICENSE("GPL");
Index: linux-2.6.31/drivers/md/dm-ioband-policy.c
===================================================================
--- /dev/null
+++ linux-2.6.31/drivers/md/dm-ioband-policy.c
@@ -0,0 +1,543 @@
+/*
+ * Copyright (C) 2008-2009 VA Linux Systems Japan K.K.
+ *
+ * I/O bandwidth control
+ *
+ * This file is released under the GPL.
+ */
+#include <linux/bio.h>
+#include <linux/workqueue.h>
+#include <linux/rbtree.h>
+#include "dm.h"
+#include "dm-ioband.h"
+
+/*
+ * The following functions determine when and which BIOs should
+ * be submitted to control the I/O flow.
+ * It is possible to add a new BIO scheduling policy with it.
+ */
+
+/*
+ * Functions for weight balancing policy based on the number of I/Os.
+ */
+#define DEFAULT_WEIGHT 100
+#define DEFAULT_TOKENPOOL 2048
+#define DEFAULT_BUCKET 2
+#define IOBAND_IOPRIO_BASE 100
+#define TOKEN_BATCH_UNIT 20
+#define PROCEED_THRESHOLD 8
+#define LOCAL_ACTIVE_RATIO 8
+#define GLOBAL_ACTIVE_RATIO 16
+#define OVERCOMMIT_RATE 4
+#define WEIGHT_MAX 100
+
+/*
+ * Calculate the effective number of tokens this group has.
+ */
+static int get_token(struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ int token = gp->c_token;
+ int allowance = dp->g_epoch - gp->c_my_epoch;
+
+ if (allowance) {
+ if (allowance > dp->g_carryover)
+ allowance = dp->g_carryover;
+ token += gp->c_token_initial * allowance;
+ }
+ if (is_group_down(gp))
+ token += gp->c_token_initial * dp->g_carryover * 2;
+
+ return token;
+}
+
+/*
+ * Calculate the priority of a given group.
+ */
+static int iopriority(struct ioband_group *gp)
+{
+ return get_token(gp) * IOBAND_IOPRIO_BASE / gp->c_token_initial + 1;
+}
+
+/*
+ * This function is called when all the active group on the same ioband
+ * device has used up their tokens. It makes a new global epoch so that
+ * all groups on this device will get freshly assigned tokens.
+ */
+static int make_global_epoch(struct ioband_device *dp)
+{
+ struct ioband_group *gp = dp->g_dominant;
+
+ /*
+ * Don't make a new epoch if the dominant group still has a lot of
+ * tokens, except when the I/O load is low.
+ */
+ if (gp) {
+ int iopri = iopriority(gp);
+ if (iopri * PROCEED_THRESHOLD > IOBAND_IOPRIO_BASE &&
+ nr_issued(dp) >= dp->g_io_throttle)
+ return 0;
+ }
+
+ dp->g_epoch++;
+ DMDEBUG("make_epoch %d", dp->g_epoch);
+
+ /* The leftover tokens will be used in the next epoch. */
+ dp->g_token_extra = dp->g_token_left;
+ if (dp->g_token_extra < 0)
+ dp->g_token_extra = 0;
+ dp->g_token_left = dp->g_token_bucket;
+
+ dp->g_expired = NULL;
+ dp->g_dominant = NULL;
+
+ return 1;
+}
+
+/*
+ * This function is called when this group has used up its own tokens.
+ * It will check whether it's possible to make a new epoch of this group.
+ */
+static inline int make_epoch(struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ int allowance = dp->g_epoch - gp->c_my_epoch;
+
+ if (!allowance)
+ return 0;
+ if (allowance > dp->g_carryover)
+ allowance = dp->g_carryover;
+ gp->c_my_epoch = dp->g_epoch;
+ return allowance;
+}
+
+/*
+ * Check whether this group has tokens to issue an I/O. Return 0 if it
+ * doesn't have any, otherwise return the priority of this group.
+ */
+static int is_token_left(struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ int allowance;
+ int delta;
+ int extra;
+
+ if (gp->c_token > 0)
+ return iopriority(gp);
+
+ if (is_group_down(gp)) {
+ gp->c_token = gp->c_token_initial;
+ return iopriority(gp);
+ }
+ allowance = make_epoch(gp);
+ if (!allowance)
+ return 0;
+ /*
+ * If this group has the right to get tokens for several epochs,
+ * give all of them to the group here.
+ */
+ delta = gp->c_token_initial * allowance;
+ dp->g_token_left -= delta;
+ /*
+ * Give some extra tokens to this group when there have left unused
+ * tokens on this ioband device from the previous epoch.
+ */
+ extra = dp->g_token_extra * gp->c_token_initial /
+ (dp->g_token_bucket - dp->g_token_extra / 2);
+ delta += extra;
+ gp->c_token += delta;
+ gp->c_consumed = 0;
+
+ if (gp == dp->g_current)
+ dp->g_yield_mark += delta;
+ DMDEBUG("refill token: gp:%p token:%d->%d extra(%d) allowance(%d)",
+ gp, gp->c_token - delta, gp->c_token, extra, allowance);
+ if (gp->c_token > 0)
+ return iopriority(gp);
+ DMDEBUG("refill token: yet empty gp:%p token:%d", gp, gp->c_token);
+ return 0;
+}
+
+/*
+ * Use tokens to issue an I/O. After the operation, the number of tokens left
+ * on this group may become negative value, which will be treated as debt.
+ */
+static int consume_token(struct ioband_group *gp, int count, int flag)
+{
+ struct ioband_device *dp = gp->c_banddev;
+
+ if (gp->c_consumed * LOCAL_ACTIVE_RATIO < gp->c_token_initial &&
+ gp->c_consumed * GLOBAL_ACTIVE_RATIO < dp->g_token_bucket) {
+ ; /* Do nothing unless this group is really active. */
+ } else if (!dp->g_dominant ||
+ get_token(gp) > get_token(dp->g_dominant)) {
+ /*
+ * Regard this group as the dominant group on this
+ * ioband device when it has larger number of tokens
+ * than those of the previous one.
+ */
+ dp->g_dominant = gp;
+ }
+ if (dp->g_epoch == gp->c_my_epoch &&
+ gp->c_token > 0 && gp->c_token - count <= 0) {
+ /* Remember the last group which used up its own tokens. */
+ dp->g_expired = gp;
+ if (dp->g_dominant == gp)
+ dp->g_dominant = NULL;
+ }
+
+ if (gp != dp->g_current) {
+ /* This group is the current already. */
+ dp->g_current = gp;
+ dp->g_yield_mark =
+ gp->c_token - (TOKEN_BATCH_UNIT << dp->g_token_unit);
+ }
+ gp->c_token -= count;
+ gp->c_consumed += count;
+ if (gp->c_token <= dp->g_yield_mark && !(flag & IOBAND_URGENT)) {
+ /*
+ * Return-value 1 means that this policy requests dm-ioband
+ * to give a chance to another group to be selected since
+ * this group has already issued enough amount of I/Os.
+ */
+ dp->g_current = NULL;
+ return R_YIELD;
+ }
+ /*
+ * Return-value 0 means that this policy allows dm-ioband to select
+ * this group to issue I/Os without a break.
+ */
+ return R_OK;
+}
+
+/*
+ * Consume one token on each I/O.
+ */
+static int prepare_token(struct ioband_group *gp, struct bio *bio, int flag)
+{
+ return consume_token(gp, 1, flag);
+}
+
+/*
+ * Check if this group is able to receive a new bio.
+ */
+static int is_queue_full(struct ioband_group *gp)
+{
+ return gp->c_blocked >= gp->c_limit;
+}
+
+static void __set_weight(struct ioband_group *gp, int weight_total,
+ int token_bucket, int limit_bucket)
+{
+ int token, limit;
+
+ if (weight_total > 0) {
+ token = token_bucket * gp->c_weight / weight_total;
+ if (token < 1)
+ token = 1;
+ limit = limit_bucket * gp->c_weight / weight_total;
+ if (limit < 1)
+ limit = 1;
+
+ /*
+ * In the hierarchical configuration,
+ * child's tokens are distributed from the parent.
+ */
+ if (gp->c_parent) {
+ gp->c_parent->c_token_initial -= token;
+ if (gp->c_parent->c_token_initial < 1)
+ gp->c_parent->c_token_initial = 1;
+
+ gp->c_parent->c_limit -= limit / OVERCOMMIT_RATE;
+ if (gp->c_parent->c_limit < 1)
+ gp->c_parent->c_limit = 1;
+ }
+ } else
+ token = limit = 1;
+
+ gp->c_token = gp->c_token_initial = gp->c_token_bucket = token;
+ gp->c_limit_bucket = limit;
+ gp->c_limit = limit / OVERCOMMIT_RATE;
+ if (gp->c_limit < 1)
+ gp->c_limit = 1;
+}
+
+static int set_weight(struct ioband_group *group, int new)
+{
+ struct ioband_device *dp = group->c_banddev;
+ struct ioband_group *parent = group->c_parent, *gp;
+ struct list_head *siblings;
+ int weight_total = 0, token_bucket, limit;
+
+ group->c_weight = new;
+
+ if (!parent) {
+ siblings = &dp->g_root_groups;
+ token_bucket = dp->g_token_bucket;
+ limit = dp->g_io_limit * 2;
+ } else {
+ siblings = &parent->c_children;
+ token_bucket = parent->c_token_bucket;
+ limit = parent->c_limit_bucket;
+ }
+
+ list_for_each_entry(gp, siblings, c_sibling)
+ weight_total += gp->c_weight;
+
+ if (parent) {
+ /*
+ * In the hierarchical configuration, each child's
+ * weight is evaluated as a percentage of its parent's
+ * bandwidth.
+ */
+ if (weight_total > WEIGHT_MAX)
+ return -EINVAL;
+ weight_total = WEIGHT_MAX;
+ }
+
+ list_for_each_entry(parent, siblings, c_sibling) {
+ struct ioband_group *this_parent = parent;
+ struct list_head *next;
+
+ __set_weight(parent, weight_total, token_bucket, limit);
+
+ repeat:
+ next = this_parent->c_children.next;
+ resume:
+ while (next != &this_parent->c_children) {
+ /* Descend the hierarchy */
+ struct list_head *tmp = next;
+
+ gp = list_entry(tmp, struct ioband_group, c_sibling);
+ next = tmp->next;
+
+ __set_weight(gp, WEIGHT_MAX,
+ this_parent->c_token_bucket,
+ this_parent->c_limit_bucket);
+
+ if (!list_empty(&gp->c_children)) {
+ this_parent = gp;
+ goto repeat;
+ }
+ }
+
+ if (this_parent != parent) {
+ /* Ascend and resume the search */
+ next = this_parent->c_sibling.next;
+ this_parent = this_parent->c_parent;
+ goto resume;
+ }
+ }
+
+ return 0;
+}
+
+static void init_token_bucket(struct ioband_device *dp,
+ int token_bucket, int carryover)
+{
+ if (!token_bucket)
+ dp->g_token_bucket = (dp->g_io_limit * 2 * DEFAULT_BUCKET) <<
+ dp->g_token_unit;
+ else
+ dp->g_token_bucket = token_bucket;
+ if (!carryover)
+ dp->g_carryover = (DEFAULT_TOKENPOOL << dp->g_token_unit) /
+ dp->g_token_bucket;
+ else
+ dp->g_carryover = carryover;
+ if (dp->g_carryover < 1)
+ dp->g_carryover = 1;
+ dp->g_token_left = 0;
+}
+
+static int policy_weight_param(struct ioband_group *gp,
+ const char *cmd, const char *value)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ long val = 0;
+ int r = 0, err = 0;
+
+ if (value)
+ err = strict_strtol(value, 0, &val);
+
+ if (!strcmp(cmd, "weight")) {
+ if (!value)
+ r = set_weight(gp, DEFAULT_WEIGHT);
+ else if (!err && 0 < val && val <= SHORT_MAX)
+ r = set_weight(gp, val);
+ else
+ r = -EINVAL;
+ } else if (!strcmp(cmd, "token")) {
+ if (!err && 0 <= val && val <= INT_MAX) {
+ init_token_bucket(dp, val, 0);
+ set_weight(gp, gp->c_weight);
+ dp->g_token_extra = 0;
+ } else
+ r = -EINVAL;
+ } else if (!strcmp(cmd, "carryover")) {
+ if (!err && 0 <= val && val <= INT_MAX) {
+ init_token_bucket(dp, dp->g_token_bucket, val);
+ set_weight(gp, gp->c_weight);
+ dp->g_token_extra = 0;
+ } else
+ r = -EINVAL;
+ } else if (!strcmp(cmd, "io_limit")) {
+ init_token_bucket(dp, 0, 0);
+ set_weight(gp, gp->c_weight);
+ } else {
+ r = -EINVAL;
+ }
+ return r;
+}
+
+static int policy_weight_ctr(struct ioband_group *gp, const char *arg)
+{
+ struct ioband_device *dp = gp->c_banddev;
+
+ gp->c_my_epoch = dp->g_epoch;
+ gp->c_weight = 0;
+ gp->c_consumed = 0;
+ return policy_weight_param(gp, "weight", arg);
+}
+
+static void policy_weight_dtr(struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ set_weight(gp, 0);
+ dp->g_dominant = NULL;
+ dp->g_expired = NULL;
+}
+
+static void policy_weight_show(struct ioband_group *gp, int *szp,
+ char *result, unsigned maxlen)
+{
+ struct ioband_group *p;
+ struct ioband_device *dp = gp->c_banddev;
+ struct rb_node *node;
+ int sz = *szp; /* used in DMEMIT() */
+
+ DMEMIT(" %d :%d", dp->g_token_bucket, gp->c_weight);
+
+ for (node = rb_first(&gp->c_group_root); node; node = rb_next(node)) {
+ p = rb_entry(node, struct ioband_group, c_group_node);
+ DMEMIT(" %d:%d", p->c_id, p->c_weight);
+ }
+ *szp = sz;
+}
+
+/*
+ * <Method> <description>
+ * g_can_submit : To determine whether a given group has the right to
+ * submit BIOs. The larger the return value the higher the
+ * priority to submit. Zero means it has no right.
+ * g_prepare_bio : Called right before submitting each BIO.
+ * g_restart_bios : Called if this ioband device has some BIOs blocked but none
+ * of them can be submitted now. This method has to
+ * reinitialize the data to restart to submit BIOs and return
+ * 0 or 1.
+ * The return value 0 means that it has become able to submit
+ * them now so that this ioband device will continue its work.
+ * The return value 1 means that it is still unable to submit
+ * them so that this device will stop its work. And this
+ * policy module has to reactivate the device when it gets
+ * to be able to submit BIOs.
+ * g_hold_bio : To hold a given BIO until it is submitted.
+ * The default function is used when this method is undefined.
+ * g_pop_bio : To select and get the best BIO to submit.
+ * g_group_ctr : To initalize the policy own members of struct ioband_group.
+ * g_group_dtr : Called when struct ioband_group is removed.
+ * g_set_param : To update the policy own date.
+ * The parameters can be passed through "dmsetup message"
+ * command.
+ * g_should_block : Called every time this ioband device receive a BIO.
+ * Return 1 if a given group can't receive any more BIOs,
+ * otherwise return 0.
+ * g_show : Show the configuration.
+ */
+static int policy_weight_init(struct ioband_device *dp, int argc, char **argv)
+{
+ long val;
+ int r = 0;
+
+ if (argc < 1)
+ val = 0;
+ else {
+ r = strict_strtol(argv[0], 0, &val);
+ if (r || val < 0 || val > INT_MAX)
+ return -EINVAL;
+ }
+
+ dp->g_can_submit = is_token_left;
+ dp->g_prepare_bio = prepare_token;
+ dp->g_restart_bios = make_global_epoch;
+ dp->g_group_ctr = policy_weight_ctr;
+ dp->g_group_dtr = policy_weight_dtr;
+ dp->g_set_param = policy_weight_param;
+ dp->g_should_block = is_queue_full;
+ dp->g_show = policy_weight_show;
+
+ dp->g_epoch = 0;
+ dp->g_weight_total = 0;
+ dp->g_current = NULL;
+ dp->g_dominant = NULL;
+ dp->g_expired = NULL;
+ dp->g_token_extra = 0;
+ dp->g_token_unit = 0;
+ init_token_bucket(dp, val, 0);
+ dp->g_token_left = dp->g_token_bucket;
+
+ return 0;
+}
+
+/* weight balancing policy based on the number of I/Os. --- End --- */
+
+/*
+ * Functions for weight balancing policy based on I/O size.
+ * It just borrows a lot of functions from the regular weight balancing policy.
+ */
+static int iosize_prepare_token(struct ioband_group *gp,
+ struct bio *bio, int flag)
+{
+ /* Consume tokens depending on the size of a given bio. */
+ return consume_token(gp, bio_sectors(bio), flag);
+}
+
+static int policy_weight_iosize_init(struct ioband_device *dp,
+ int argc, char **argv)
+{
+ long val;
+ int r = 0;
+
+ if (argc < 1)
+ val = 0;
+ else {
+ r = strict_strtol(argv[0], 0, &val);
+ if (r || val < 0 || val > INT_MAX)
+ return -EINVAL;
+ }
+
+ r = policy_weight_init(dp, argc, argv);
+ if (r < 0)
+ return r;
+
+ dp->g_prepare_bio = iosize_prepare_token;
+ dp->g_token_unit = PAGE_SHIFT - 9;
+ init_token_bucket(dp, val, 0);
+ dp->g_token_left = dp->g_token_bucket;
+ return 0;
+}
+
+/* weight balancing policy based on I/O size. --- End --- */
+
+static int policy_default_init(struct ioband_device *dp, int argc, char **argv)
+{
+ return policy_weight_init(dp, argc, argv);
+}
+
+const struct ioband_policy_type dm_ioband_policy_type[] = {
+ { "default", policy_default_init },
+ { "weight", policy_weight_init },
+ { "weight-iosize", policy_weight_iosize_init },
+ { "range-bw", policy_range_bw_init },
+ { NULL, policy_default_init }
+};
Index: linux-2.6.31/drivers/md/dm-ioband-type.c
===================================================================
--- /dev/null
+++ linux-2.6.31/drivers/md/dm-ioband-type.c
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2008-2009 VA Linux Systems Japan K.K.
+ *
+ * I/O bandwidth control
+ *
+ * This file is released under the GPL.
+ */
+#include <linux/bio.h>
+#include "dm.h"
+#include "dm-ioband.h"
+
+/*
+ * Any I/O bandwidth can be divided into several bandwidth groups, each of which
+ * has its own unique ID. The following functions are called to determine
+ * which group a given BIO belongs to and return the ID of the group.
+ */
+
+/* ToDo: unsigned long value would be better for group ID */
+
+static int ioband_process_id(struct bio *bio)
+{
+ /*
+ * This function will work for KVM and Xen.
+ */
+ return (int)current->tgid;
+}
+
+static int ioband_process_group(struct bio *bio)
+{
+ return (int)task_pgrp_nr(current);
+}
+
+static int ioband_uid(struct bio *bio)
+{
+ return (int)current_uid();
+}
+
+static int ioband_gid(struct bio *bio)
+{
+ return (int)current_gid();
+}
+
+static int ioband_cpuset(struct bio *bio)
+{
+ return 0; /* not implemented yet */
+}
+
+static int ioband_node(struct bio *bio)
+{
+ return 0; /* not implemented yet */
+}
+
+static int ioband_cgroup(struct bio *bio)
+{
+ /*
+ * This function should return the ID of the cgroup which
+ * issued "bio". The ID of the cgroup which the current
+ * process belongs to won't be suitable ID for this purpose,
+ * since some BIOs will be handled by kernel threads like aio
+ * or pdflush on behalf of the process requesting the BIOs.
+ */
+ return 0; /* not implemented yet */
+}
+
+const struct ioband_group_type dm_ioband_group_type[] = {
+ { "none", NULL },
+ { "pgrp", ioband_process_group },
+ { "pid", ioband_process_id },
+ { "node", ioband_node },
+ { "cpuset", ioband_cpuset },
+ { "cgroup", ioband_cgroup },
+ { "user", ioband_uid },
+ { "uid", ioband_uid },
+ { "gid", ioband_gid },
+ { NULL, NULL}
+};
Index: linux-2.6.31/drivers/md/dm-ioband.h
===================================================================
--- /dev/null
+++ linux-2.6.31/drivers/md/dm-ioband.h
@@ -0,0 +1,231 @@
+/*
+ * Copyright (C) 2008-2009 VA Linux Systems Japan K.K.
+ *
+ * I/O bandwidth control
+ *
+ * This file is released under the GPL.
+ */
+
+#ifndef DM_IOBAND_H
+#define DM_IOBAND_H
+
+#include <linux/version.h>
+#include <linux/wait.h>
+
+#define DM_MSG_PREFIX "ioband"
+
+#define DEFAULT_IO_THROTTLE 4
+#define IOBAND_NAME_MAX 31
+#define IOBAND_ID_ANY (-1)
+#define POLICY_PARAM_START 6
+#define POLICY_PARAM_DELIM "=:,"
+
+#define MAX_BW_OVER 1
+#define MAX_BW_UNDER 0
+#define NO_IO_MODE 4
+
+#define TIME_COMPENSATOR 10
+
+struct ioband_group;
+
+struct ioband_device {
+ struct list_head g_groups;
+ struct delayed_work g_conductor;
+ struct workqueue_struct *g_ioband_wq;
+ struct bio_list g_urgent_bios;
+ int g_io_throttle;
+ int g_io_limit;
+ int g_issued[2];
+ int g_blocked;
+ spinlock_t g_lock;
+ wait_queue_head_t g_waitq;
+ wait_queue_head_t g_waitq_suspend;
+ wait_queue_head_t g_waitq_flush;
+
+ int g_ref;
+ struct list_head g_list;
+ struct list_head g_root_groups;
+ int g_flags;
+ char g_name[IOBAND_NAME_MAX + 1];
+ const struct ioband_policy_type *g_policy;
+
+ /* policy dependent */
+ int (*g_can_submit) (struct ioband_group *);
+ int (*g_prepare_bio) (struct ioband_group *, struct bio *, int);
+ int (*g_restart_bios) (struct ioband_device *);
+ void (*g_hold_bio) (struct ioband_group *, struct bio *);
+ struct bio *(*g_pop_bio) (struct ioband_group *);
+ int (*g_group_ctr) (struct ioband_group *, const char *);
+ void (*g_group_dtr) (struct ioband_group *);
+ int (*g_set_param) (struct ioband_group *, const char *, const char *);
+ int (*g_should_block) (struct ioband_group *);
+ void (*g_show) (struct ioband_group *, int *, char *, unsigned);
+
+ /* members for weight balancing policy */
+ int g_epoch;
+ int g_weight_total;
+ /* the number of tokens which can be used in every epoch */
+ int g_token_bucket;
+ /* how many epochs tokens can be carried over */
+ int g_carryover;
+ /* how many tokens should be used for one page-sized I/O */
+ int g_token_unit;
+ /* the last group which used a token */
+ struct ioband_group *g_current;
+ /* give another group a chance to be scheduled when the rest
+ of tokens of the current group reaches this mark */
+ int g_yield_mark;
+ /* the latest group which used up its tokens */
+ struct ioband_group *g_expired;
+ /* the group which has the largest number of tokens in the
+ active groups */
+ struct ioband_group *g_dominant;
+ /* the number of unused tokens in this epoch */
+ int g_token_left;
+ /* left-over tokens from the previous epoch */
+ int g_token_extra;
+
+ /* members for range-bw policy */
+ int g_min_bw_total;
+ int g_max_bw_total;
+ unsigned long g_next_time_period;
+ int g_time_period_expired;
+ struct ioband_group *g_running_gp;
+ int g_total_min_bw_token;
+ int g_consumed_min_bw_token;
+ int g_io_mode;
+
+};
+
+struct ioband_group {
+ struct list_head c_list;
+ struct list_head c_sibling;
+ struct list_head c_children;
+ struct ioband_group *c_parent;
+ struct ioband_device *c_banddev;
+ struct dm_dev *c_dev;
+ struct dm_target *c_target;
+ struct bio_list c_blocked_bios;
+ struct bio_list c_prio_bios;
+ struct rb_root c_group_root;
+ struct rb_node c_group_node;
+ int c_id; /* should be unsigned long or unsigned long long */
+ char c_name[IOBAND_NAME_MAX + 1]; /* rfu */
+ int c_blocked;
+ int c_prio_blocked;
+ wait_queue_head_t c_waitq;
+ int c_flags;
+ struct disk_stats c_stats; /* hold rd/wr status */
+ const struct ioband_group_type *c_type;
+
+ /* members for weight balancing policy */
+ int c_weight;
+ int c_my_epoch;
+ int c_token;
+ int c_token_initial;
+ int c_token_bucket;
+ int c_limit;
+ int c_limit_bucket;
+ int c_consumed;
+
+ /* rfu */
+ /* struct bio_list c_ordered_tag_bios; */
+
+ /* members for range-bw policy */
+ wait_queue_head_t c_max_bw_over_waitq;
+ struct timer_list *c_timer;
+ int timer_set;
+ int c_min_bw;
+ int c_max_bw;
+ int c_time_slice_expired;
+ int c_min_bw_token;
+ int c_max_bw_token;
+ int c_consumed_min_bw_token;
+ int c_is_over_max_bw;
+ int c_io_mode;
+ unsigned long c_time_slice;
+ unsigned long c_time_slice_start;
+ unsigned long c_time_slice_end;
+ int c_wait_p_count;
+
+};
+
+#define IOBAND_URGENT 1
+
+#define DEV_BIO_BLOCKED 1
+#define DEV_SUSPENDED 2
+
+#define set_device_blocked(dp) ((dp)->g_flags |= DEV_BIO_BLOCKED)
+#define clear_device_blocked(dp) ((dp)->g_flags &= ~DEV_BIO_BLOCKED)
+#define is_device_blocked(dp) ((dp)->g_flags & DEV_BIO_BLOCKED)
+
+#define set_device_suspended(dp) ((dp)->g_flags |= DEV_SUSPENDED)
+#define clear_device_suspended(dp) ((dp)->g_flags &= ~DEV_SUSPENDED)
+#define is_device_suspended(dp) ((dp)->g_flags & DEV_SUSPENDED)
+
+#define IOG_PRIO_BIO_SYNC 1
+#define IOG_PRIO_QUEUE 2
+#define IOG_BIO_BLOCKED 4
+#define IOG_GOING_DOWN 8
+#define IOG_SUSPENDED 16
+#define IOG_NEED_UP 32
+
+#define R_OK 0
+#define R_BLOCK 1
+#define R_YIELD 2
+
+#define set_group_blocked(gp) ((gp)->c_flags |= IOG_BIO_BLOCKED)
+#define clear_group_blocked(gp) ((gp)->c_flags &= ~IOG_BIO_BLOCKED)
+#define is_group_blocked(gp) ((gp)->c_flags & IOG_BIO_BLOCKED)
+
+#define set_group_down(gp) ((gp)->c_flags |= IOG_GOING_DOWN)
+#define clear_group_down(gp) ((gp)->c_flags &= ~IOG_GOING_DOWN)
+#define is_group_down(gp) ((gp)->c_flags & IOG_GOING_DOWN)
+
+#define set_group_suspended(gp) ((gp)->c_flags |= IOG_SUSPENDED)
+#define clear_group_suspended(gp) ((gp)->c_flags &= ~IOG_SUSPENDED)
+#define is_group_suspended(gp) ((gp)->c_flags & IOG_SUSPENDED)
+
+#define set_group_need_up(gp) ((gp)->c_flags |= IOG_NEED_UP)
+#define clear_group_need_up(gp) ((gp)->c_flags &= ~IOG_NEED_UP)
+#define group_need_up(gp) ((gp)->c_flags & IOG_NEED_UP)
+
+#define set_prio_async(gp) ((gp)->c_flags |= IOG_PRIO_QUEUE)
+#define clear_prio_async(gp) ((gp)->c_flags &= ~IOG_PRIO_QUEUE)
+#define is_prio_async(gp) \
+ ((gp)->c_flags & (IOG_PRIO_QUEUE|IOG_PRIO_BIO_SYNC) == IOG_PRIO_QUEUE)
+
+#define set_prio_sync(gp) \
+ ((gp)->c_flags |= (IOG_PRIO_QUEUE|IOG_PRIO_BIO_SYNC))
+#define clear_prio_sync(gp) \
+ ((gp)->c_flags &= ~(IOG_PRIO_QUEUE|IOG_PRIO_BIO_SYNC))
+#define is_prio_sync(gp) \
+ ((gp)->c_flags & (IOG_PRIO_QUEUE|IOG_PRIO_BIO_SYNC) == \
+ (IOG_PRIO_QUEUE|IOG_PRIO_BIO_SYNC))
+
+#define set_prio_queue(gp, sync) \
+ ((gp)->c_flags |= (IOG_PRIO_QUEUE|sync))
+#define clear_prio_queue(gp) clear_prio_sync(gp)
+#define is_prio_queue(gp) ((gp)->c_flags & IOG_PRIO_QUEUE)
+#define prio_queue_sync(gp) ((gp)->c_flags & IOG_PRIO_BIO_SYNC)
+
+#define nr_issued(dp) \
+ ((dp)->g_issued[BLK_RW_SYNC] + (dp)->g_issued[BLK_RW_ASYNC])
+
+struct ioband_policy_type {
+ const char *p_name;
+ int (*p_policy_init) (struct ioband_device *, int, char **);
+};
+
+extern const struct ioband_policy_type dm_ioband_policy_type[];
+
+struct ioband_group_type {
+ const char *t_name;
+ int (*t_getid) (struct bio *);
+};
+
+extern const struct ioband_group_type dm_ioband_group_type[];
+
+extern int policy_range_bw_init(struct ioband_device *, int, char **);
+
+#endif /* DM_IOBAND_H */
Index: linux-2.6.31/drivers/md/dm-ioband-rangebw.c
===================================================================
--- /dev/null
+++ linux-2.6.31/drivers/md/dm-ioband-rangebw.c
@@ -0,0 +1,669 @@
+/*
+ * dm-ioband-rangebw.c
+ *
+ * This is a I/O control policy to support the Range Bandwidth in Disk I/O.
+ * And this policy is for dm-ioband controller by Ryo Tsuruta,
+ * Hirokazu Takahashi
+ *
+ * Copyright (C) 2008 - 2011
+ * Electronics and Telecommunications Research Institute(ETRI)
+ *
+ * This program is free software. you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License(GPL) as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Contact Information:
+ * Dong-Jae, Kang <[email protected]>, Chei-Yol,Kim <[email protected]>,
+ * Sung-In,Jung <[email protected]>
+ */
+
+#include <linux/bio.h>
+#include <linux/workqueue.h>
+#include <linux/rbtree.h>
+#include <linux/jiffies.h>
+#include <linux/random.h>
+#include <linux/time.h>
+#include <linux/timer.h>
+#include "dm.h"
+#include "md.h"
+#include "dm-ioband.h"
+
+static void range_bw_timeover(unsigned long);
+static void range_bw_timer_register(struct timer_list *,
+ unsigned long, unsigned long);
+
+/*
+ * Functions for Range Bandwidth(range-bw) policy based on
+ * the time slice and token.
+ */
+#define DEFAULT_BUCKET 2
+#define DEFAULT_TOKENPOOL 2048
+
+#define TIME_SLICE_EXPIRED 1
+#define TIME_SLICE_NOT_EXPIRED 0
+
+#define MINBW_IO_MODE 0
+#define LEFTOVER_IO_MODE 1
+#define RANGE_IO_MODE 2
+#define DEFAULT_IO_MODE 3
+#define NO_IO_MODE 4
+
+#define MINBW_PRIO_BASE 10
+#define OVER_IO_RATE 4
+
+#define DEFAULT_RANGE_BW "0:0"
+#define DEFAULT_MIN_BW 0
+#define DEFAULT_MAX_BW 0
+
+static const int time_slice_base = HZ / 10;
+static const int range_time_slice_base = HZ / 50;
+static void do_nothing(void) {}
+/*
+ * g_restart_bios function for range-bw policy
+ */
+static int range_bw_restart_bios(struct ioband_device *dp)
+{
+ return 1;
+}
+
+/*
+ * Allocate the time slice when IO mode is MINBW_IO_MODE,
+ * RANGE_IO_MODE or LEFTOVER_IO_MODE
+ */
+static int set_time_slice(struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ int dp_io_mode, gp_io_mode;
+ unsigned long now = jiffies;
+
+ dp_io_mode = dp->g_io_mode;
+ gp_io_mode = gp->c_io_mode;
+
+ gp->c_time_slice_start = now;
+
+ if (dp_io_mode == LEFTOVER_IO_MODE) {
+ gp->c_time_slice_end = now + gp->c_time_slice;
+ return 0;
+ }
+
+ if (gp_io_mode == MINBW_IO_MODE)
+ gp->c_time_slice_end = now + gp->c_time_slice;
+ else if (gp_io_mode == RANGE_IO_MODE)
+ gp->c_time_slice_end = now + range_time_slice_base;
+ else if (gp_io_mode == DEFAULT_IO_MODE)
+ gp->c_time_slice_end = now + time_slice_base;
+ else if (gp_io_mode == NO_IO_MODE) {
+ gp->c_time_slice_end = 0;
+ gp->c_time_slice_expired = TIME_SLICE_EXPIRED;
+ return 0;
+ }
+
+ gp->c_time_slice_expired = TIME_SLICE_NOT_EXPIRED;
+
+ return 0;
+}
+
+/*
+ * Calculate the priority of given ioband_group
+ */
+static int range_bw_priority(struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ int prio = 0;
+
+ if (dp->g_io_mode == LEFTOVER_IO_MODE) {
+ prio = random32() % MINBW_PRIO_BASE;
+ if (prio == 0)
+ prio = 1;
+ } else if (gp->c_io_mode == MINBW_IO_MODE) {
+ prio = (gp->c_min_bw_token - gp->c_consumed_min_bw_token) *
+ MINBW_PRIO_BASE;
+ } else if (gp->c_io_mode == DEFAULT_IO_MODE) {
+ prio = MINBW_PRIO_BASE;
+ } else if (gp->c_io_mode == RANGE_IO_MODE) {
+ prio = MINBW_PRIO_BASE / 2;
+ } else {
+ prio = 0;
+ }
+
+ return prio;
+}
+
+/*
+ * Check whether this group has right to issue an I/O in range-bw policy mode.
+ * Return 0 if it doesn't have right, otherwise return the non-zero value.
+ */
+static int has_right_to_issue(struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ int prio;
+
+ if (gp->c_prio_blocked > 0 || gp->c_blocked - gp->c_prio_blocked > 0) {
+ prio = range_bw_priority(gp);
+ if (prio <= 0)
+ return 1;
+ return prio;
+ }
+
+ if (gp == dp->g_running_gp) {
+
+ if (gp->c_time_slice_expired == TIME_SLICE_EXPIRED) {
+
+ gp->c_time_slice_expired = TIME_SLICE_NOT_EXPIRED;
+ gp->c_time_slice_end = 0;
+
+ return 0;
+ }
+
+ if (gp->c_time_slice_end == 0)
+ set_time_slice(gp);
+
+ return range_bw_priority(gp);
+
+ }
+
+ dp->g_running_gp = gp;
+ set_time_slice(gp);
+
+ return range_bw_priority(gp);
+}
+
+/*
+ * Reset all variables related with range-bw token and time slice
+ */
+static int reset_range_bw_token(struct ioband_group *gp, unsigned long now)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ struct ioband_group *p;
+
+ list_for_each_entry(p, &dp->g_groups, c_list) {
+ p->c_consumed_min_bw_token = 0;
+ p->c_is_over_max_bw = MAX_BW_UNDER;
+ if (p->c_io_mode != DEFAULT_IO_MODE)
+ p->c_io_mode = MINBW_IO_MODE;
+ }
+
+ dp->g_consumed_min_bw_token = 0;
+
+ dp->g_next_time_period = now + HZ;
+ dp->g_time_period_expired = TIME_SLICE_NOT_EXPIRED;
+ dp->g_io_mode = MINBW_IO_MODE;
+
+ list_for_each_entry(p, &dp->g_groups, c_list) {
+ if (waitqueue_active(&p->c_max_bw_over_waitq))
+ wake_up_all(&p->c_max_bw_over_waitq);
+ }
+ return 0;
+}
+
+/*
+ * Use tokens(Increase the number of consumed token) to issue an I/O
+ * for guranteeing the range-bw. and check the expiration of local and
+ * global time slice, and overflow of max bw
+ */
+static int range_bw_consume_token(struct ioband_group *gp, int count, int flag)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ struct ioband_group *p;
+ unsigned long now = jiffies;
+
+ dp->g_current = gp;
+
+ if (dp->g_next_time_period == 0) {
+ dp->g_next_time_period = now + HZ;
+ dp->g_time_period_expired = TIME_SLICE_NOT_EXPIRED;
+ }
+
+ if (time_after(now, dp->g_next_time_period)) {
+ reset_range_bw_token(gp, now);
+ } else {
+ gp->c_consumed_min_bw_token += count;
+ dp->g_consumed_min_bw_token += count;
+
+ if (gp->c_max_bw > 0 && gp->c_consumed_min_bw_token >=
+ gp->c_max_bw_token) {
+ gp->c_is_over_max_bw = MAX_BW_OVER;
+ gp->c_io_mode = NO_IO_MODE;
+ return R_YIELD;
+ }
+
+ if (gp->c_io_mode != RANGE_IO_MODE && gp->c_min_bw_token <=
+ gp->c_consumed_min_bw_token) {
+ gp->c_io_mode = RANGE_IO_MODE;
+
+ if (dp->g_total_min_bw_token <=
+ dp->g_consumed_min_bw_token) {
+ list_for_each_entry(p, &dp->g_groups, c_list) {
+ if (p->c_io_mode != RANGE_IO_MODE &&
+ p->c_io_mode != DEFAULT_IO_MODE)
+ goto out;
+ }
+
+ if (dp->g_io_mode == MINBW_IO_MODE)
+ dp->g_io_mode = LEFTOVER_IO_MODE;
+ out:;
+ }
+ }
+ }
+
+ if (gp->c_time_slice_end != 0 &&
+ time_after(now, gp->c_time_slice_end)) {
+ gp->c_time_slice_expired = TIME_SLICE_EXPIRED;
+ return R_YIELD;
+ }
+
+ return R_OK;
+}
+
+static int is_no_io_mode(struct ioband_group *gp)
+{
+ if (gp->c_io_mode == NO_IO_MODE)
+ return 1;
+
+ return 0;
+}
+
+/*
+ * Check if this group is able to receive a new bio.
+ * in range bw policy, we only check that ioband device should be blocked
+ */
+static int range_bw_queue_full(struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ unsigned long now, time_step;
+
+ if (is_no_io_mode(gp)) {
+ now = jiffies;
+ if (time_after(dp->g_next_time_period, now)) {
+ time_step = dp->g_next_time_period - now;
+ range_bw_timer_register(gp->c_timer,
+ (time_step + TIME_COMPENSATOR),
+ (unsigned long)gp);
+ wait_event_lock_irq(gp->c_max_bw_over_waitq,
+ !is_no_io_mode(gp),
+ dp->g_lock, do_nothing());
+ }
+ }
+
+ return (gp->c_blocked >= gp->c_limit);
+}
+
+/*
+ * Convert the bw valuse to the number of bw token
+ * bw : Kbyte unit bandwidth
+ * token_base : the number of tokens used for one 1Kbyte-size IO
+ * -- Attention : Currently, We support the 512byte or 1Kbyte per 1 token
+ */
+static int convert_bw_to_token(int bw, int token_unit)
+{
+ int token;
+ int token_base;
+
+ token_base = (1 << token_unit) / 4;
+ token = bw * token_base;
+
+ return token;
+}
+
+
+/*
+ * Allocate the time slice for MINBW_IO_MODE to each group
+ */
+static void range_bw_time_slice_init(struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ struct ioband_group *p;
+
+ list_for_each_entry(p, &dp->g_groups, c_list) {
+
+ if (dp->g_min_bw_total == 0)
+ p->c_time_slice = time_slice_base;
+ else
+ p->c_time_slice = time_slice_base +
+ ((time_slice_base *
+ ((p->c_min_bw + p->c_max_bw) / 2)) /
+ dp->g_min_bw_total);
+ }
+}
+
+/*
+ * Allocate the range_bw and range_bw_token to the given group
+ */
+static void set_range_bw(struct ioband_group *gp, int new_min, int new_max)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ struct ioband_group *p;
+ int token_unit;
+
+ dp->g_min_bw_total += (new_min - gp->c_min_bw);
+ gp->c_min_bw = new_min;
+
+ dp->g_max_bw_total += (new_max - gp->c_max_bw);
+ gp->c_max_bw = new_max;
+
+ if (new_min)
+ gp->c_io_mode = MINBW_IO_MODE;
+ else
+ gp->c_io_mode = DEFAULT_IO_MODE;
+
+ range_bw_time_slice_init(gp);
+
+ token_unit = dp->g_token_unit;
+ gp->c_min_bw_token = convert_bw_to_token(new_min, token_unit);
+ dp->g_total_min_bw_token =
+ convert_bw_to_token(dp->g_min_bw_total, token_unit);
+
+ gp->c_max_bw_token = convert_bw_to_token(new_max, token_unit);
+
+ if (dp->g_min_bw_total == 0) {
+ list_for_each_entry(p, &dp->g_groups, c_list)
+ p->c_limit = 1;
+ } else {
+ list_for_each_entry(p, &dp->g_groups, c_list) {
+ p->c_limit = dp->g_io_limit * 2 * p->c_min_bw /
+ dp->g_min_bw_total / OVER_IO_RATE + 1;
+ }
+ }
+
+ return;
+}
+
+/*
+ * Allocate the min_bw and min_bw_token to the given group
+ */
+static void set_min_bw(struct ioband_group *gp, int new)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ struct ioband_group *p;
+ int token_unit;
+
+ dp->g_min_bw_total += (new - gp->c_min_bw);
+ gp->c_min_bw = new;
+
+ if (new)
+ gp->c_io_mode = MINBW_IO_MODE;
+ else
+ gp->c_io_mode = DEFAULT_IO_MODE;
+
+ range_bw_time_slice_init(gp);
+
+ token_unit = dp->g_token_unit;
+ gp->c_min_bw_token = convert_bw_to_token(gp->c_min_bw, token_unit);
+ dp->g_total_min_bw_token =
+ convert_bw_to_token(dp->g_min_bw_total, token_unit);
+
+ if (dp->g_min_bw_total == 0) {
+ list_for_each_entry(p, &dp->g_groups, c_list)
+ p->c_limit = 1;
+ } else {
+ list_for_each_entry(p, &dp->g_groups, c_list) {
+ p->c_limit = dp->g_io_limit * 2 * p->c_min_bw /
+ dp->g_min_bw_total / OVER_IO_RATE + 1;
+ }
+ }
+
+ return;
+}
+
+/*
+ * Allocate the max_bw and max_bw_token to the pointed group
+ */
+static void set_max_bw(struct ioband_group *gp, int new)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ int token_unit;
+
+ token_unit = dp->g_token_unit;
+
+ dp->g_max_bw_total += (new - gp->c_max_bw);
+ gp->c_max_bw = new;
+ gp->c_max_bw_token = convert_bw_to_token(new, token_unit);
+
+ range_bw_time_slice_init(gp);
+
+ return;
+
+}
+
+static void init_range_bw_token_bucket(struct ioband_device *dp, int val)
+{
+ dp->g_token_bucket = (dp->g_io_limit * 2 * DEFAULT_BUCKET) <<
+ dp->g_token_unit;
+ if (!val)
+ val = DEFAULT_TOKENPOOL << dp->g_token_unit;
+ if (val < dp->g_token_bucket)
+ val = dp->g_token_bucket;
+ dp->g_carryover = val/dp->g_token_bucket;
+ dp->g_token_left = 0;
+}
+
+static int policy_range_bw_param(struct ioband_group *gp,
+ const char *cmd, const char *value)
+{
+ long val = 0, min_val = DEFAULT_MIN_BW, max_val = DEFAULT_MAX_BW;
+ int r = 0, err = 0;
+ char *endp;
+
+ if (value) {
+ min_val = simple_strtol(value, &endp, 0);
+ if (strchr(POLICY_PARAM_DELIM, *endp)) {
+ max_val = simple_strtol(endp + 1, &endp, 0);
+ if (*endp != '\0')
+ err++;
+ } else
+ err++;
+ }
+
+ if (!strcmp(cmd, "range-bw")) {
+ if (!err && 0 <= min_val &&
+ min_val <= (INT_MAX / 2) && 0 <= max_val &&
+ max_val <= (INT_MAX / 2) && min_val <= max_val)
+ set_range_bw(gp, min_val, max_val);
+ else
+ r = -EINVAL;
+ } else if (!strcmp(cmd, "min-bw")) {
+ if (!err && 0 <= val && val <= (INT_MAX / 2))
+ set_min_bw(gp, val);
+ else
+ r = -EINVAL;
+ } else if (!strcmp(cmd, "max-bw")) {
+ if ((!err && 0 <= val && val <= (INT_MAX / 2) &&
+ gp->c_min_bw <= val) || val == 0)
+ set_max_bw(gp, val);
+ else
+ r = -EINVAL;
+ } else {
+ r = -EINVAL;
+ }
+ return r;
+}
+
+static int policy_range_bw_ctr(struct ioband_group *gp, const char *arg)
+{
+ int ret;
+
+ init_waitqueue_head(&gp->c_max_bw_over_waitq);
+
+ gp->c_min_bw = 0;
+ gp->c_max_bw = 0;
+ gp->c_io_mode = DEFAULT_IO_MODE;
+ gp->c_time_slice_expired = TIME_SLICE_NOT_EXPIRED;
+ gp->c_min_bw_token = 0;
+ gp->c_max_bw_token = 0;
+ gp->c_consumed_min_bw_token = 0;
+ gp->c_is_over_max_bw = MAX_BW_UNDER;
+ gp->c_time_slice_start = 0;
+ gp->c_time_slice_end = 0;
+ gp->c_wait_p_count = 0;
+
+ gp->c_time_slice = time_slice_base;
+
+ gp->c_timer = kmalloc(sizeof(struct timer_list), GFP_KERNEL);
+ if (gp->c_timer == NULL)
+ return -EINVAL;
+ memset(gp->c_timer, 0, sizeof(struct timer_list));
+ gp->timer_set = 0;
+
+ ret = policy_range_bw_param(gp, "range-bw", arg);
+
+ return ret;
+}
+
+static void policy_range_bw_dtr(struct ioband_group *gp)
+{
+ struct ioband_device *dp = gp->c_banddev;
+
+ gp->c_time_slice = 0;
+ set_range_bw(gp, 0, 0);
+
+ dp->g_running_gp = NULL;
+
+ if (gp->c_timer != NULL) {
+ del_timer(gp->c_timer);
+ kfree(gp->c_timer);
+ }
+}
+
+static void policy_range_bw_show(struct ioband_group *gp, int *szp,
+ char *result, unsigned int maxlen)
+{
+ struct ioband_group *p;
+ struct ioband_device *dp = gp->c_banddev;
+ struct rb_node *node;
+ int sz = *szp; /* used in DMEMIT() */
+
+ DMEMIT(" %d :%d:%d", dp->g_token_bucket * dp->g_carryover,
+ gp->c_min_bw, gp->c_max_bw);
+
+ for (node = rb_first(&gp->c_group_root); node; node = rb_next(node)) {
+ p = rb_entry(node, struct ioband_group, c_group_node);
+ DMEMIT(" %d:%d:%d", p->c_id, p->c_min_bw, p->c_max_bw);
+ }
+ *szp = sz;
+}
+
+static int range_bw_prepare_token(struct ioband_group *gp,
+ struct bio *bio, int flag)
+{
+ struct ioband_device *dp = gp->c_banddev;
+ int unit;
+ int bio_count;
+ int token_count = 0;
+
+ unit = (1 << dp->g_token_unit);
+ bio_count = bio_sectors(bio);
+
+ if (unit == 8)
+ token_count = bio_count;
+ else if (unit == 4)
+ token_count = bio_count / 2;
+ else if (unit == 2)
+ token_count = bio_count / 4;
+ else if (unit == 1)
+ token_count = bio_count / 8;
+
+ return range_bw_consume_token(gp, token_count, flag);
+}
+
+static void range_bw_timer_register(struct timer_list *ptimer,
+ unsigned long timeover, unsigned long gp)
+{
+ struct ioband_group *group = (struct ioband_group *)gp;
+
+ if (group->timer_set == 0) {
+ init_timer(ptimer);
+ ptimer->expires = get_jiffies_64() + timeover;
+ ptimer->data = gp;
+ ptimer->function = range_bw_timeover;
+ add_timer(ptimer);
+ group->timer_set = 1;
+ }
+}
+
+/*
+ * Timer Handler function to protect the all processes's hanging in
+ * lower min-bw configuration
+ */
+static void range_bw_timeover(unsigned long gp)
+{
+ struct ioband_group *group = (struct ioband_group *)gp;
+
+ if (group->c_is_over_max_bw == MAX_BW_OVER)
+ group->c_is_over_max_bw = MAX_BW_UNDER;
+
+ if (group->c_io_mode == NO_IO_MODE)
+ group->c_io_mode = MINBW_IO_MODE;
+
+ if (waitqueue_active(&group->c_max_bw_over_waitq))
+ wake_up_all(&group->c_max_bw_over_waitq);
+
+ group->timer_set = 0;
+}
+
+/*
+ * <Method> <description>
+ * g_can_submit : To determine whether a given group has the right to
+ * submit BIOs. The larger the return value the higher the
+ * priority to submit. Zero means it has no right.
+ * g_prepare_bio : Called right before submitting each BIO.
+ * g_restart_bios : Called if this ioband device has some BIOs blocked but none
+ * of them can be submitted now. This method has to
+ * reinitialize the data to restart to submit BIOs and return
+ * 0 or 1.
+ * The return value 0 means that it has become able to submit
+ * them now so that this ioband device will continue its work.
+ * The return value 1 means that it is still unable to submit
+ * them so that this device will stop its work. And this
+ * policy module has to reactivate the device when it gets
+ * to be able to submit BIOs.
+ * g_hold_bio : To hold a given BIO until it is submitted.
+ * The default function is used when this method is undefined.
+ * g_pop_bio : To select and get the best BIO to submit.
+ * g_group_ctr : To initalize the policy own members of struct ioband_group.
+ * g_group_dtr : Called when struct ioband_group is removed.
+ * g_set_param : To update the policy own date.
+ * The parameters can be passed through "dmsetup message"
+ * command.
+ * g_should_block : Called every time this ioband device receive a BIO.
+ * Return 1 if a given group can't receive any more BIOs,
+ * otherwise return 0.
+ * g_show : Show the configuration.
+ */
+
+int policy_range_bw_init(struct ioband_device *dp, int argc, char **argv)
+{
+ long val;
+ int r = 0;
+
+ if (argc < 1)
+ val = 0;
+ else {
+ r = strict_strtol(argv[0], 0, &val);
+ if (r || val < 0)
+ return -EINVAL;
+ }
+
+ dp->g_can_submit = has_right_to_issue;
+ dp->g_prepare_bio = range_bw_prepare_token;
+ dp->g_restart_bios = range_bw_restart_bios;
+ dp->g_group_ctr = policy_range_bw_ctr;
+ dp->g_group_dtr = policy_range_bw_dtr;
+ dp->g_set_param = policy_range_bw_param;
+ dp->g_should_block = range_bw_queue_full;
+ dp->g_show = policy_range_bw_show;
+
+ dp->g_min_bw_total = 0;
+ dp->g_running_gp = NULL;
+ dp->g_total_min_bw_token = 0;
+ dp->g_io_mode = MINBW_IO_MODE;
+ dp->g_consumed_min_bw_token = 0;
+ dp->g_current = NULL;
+ dp->g_next_time_period = 0;
+ dp->g_time_period_expired = TIME_SLICE_NOT_EXPIRED;
+
+ dp->g_token_unit = PAGE_SHIFT - 9;
+ init_range_bw_token_bucket(dp, val);
+
+ return 0;
+}
Index: linux-2.6.31/Documentation/device-mapper/range-bw.txt
===================================================================
--- /dev/null
+++ linux-2.6.31/Documentation/device-mapper/range-bw.txt
@@ -0,0 +1,99 @@
+Range-BW I/O controller by Dong-Jae Kang <[email protected]>
+
+
+1. Introduction
+===============
+
+The design of Range-BW is related with three another parts, Cgroup,
+bio-cgroup (or blkio-cgroup) and dm-ioband and it was implemented as
+an additional controller for dm-ioband.
+Cgroup framework is used to support process grouping mechanism and
+bio-cgroup is used to control delayed I/O or non-direct I/O. Finally,
+dm-ioband is a kind of I/O controller allowing the proportional I/O
+bandwidth to process groups based on its priority.
+The supposed controller supports the process group-based range
+bandwidth according to the priority or importance of the group. Range
+bandwidth means the predicable I/O bandwidth with minimum and maximum
+value defined by administrator.
+
+Minimum I/O bandwidth should be guaranteed for stable performance or
+reliability of specific service and I/O bandwidth over maximum should
+be throttled to protect the limited I/O resource from
+over-provisioning in unnecessary usage or to reserve the I/O bandwidth
+for another use.
+So, Range-BW was implemented to include the two concepts, guaranteeing
+of minimum I/O requirement and limitation of unnecessary bandwidth
+depending on its priority.
+And it was implemented as device mapper driver such like dm-ioband.
+So, it is independent of the underlying specific I/O scheduler, for
+example, CFQ, AS, NOOP, deadline and so on.
+
+* Attention
+Range-BW supports the predicable I/O bandwidth, but it should be
+configured in the scope of total I/O bandwidth of the I/O system to
+guarantee the minimum I/O requirement. For example, if total I/O
+bandwidth is 40Mbytes/sec,
+
+the summary of I/O bandwidth configured in each process group should
+be equal or smaller than 40Mbytes/sec.
+So, we need to check total I/O bandwidth before set it up.
+
+2. Setup and Installation
+=========================
+
+This part is same with dm-ioband,
+../../Documentation/device-mapper/ioband.txt or
+http://sourceforge.net/apps/trac/ioband/wiki/dm-ioband/man/setup
+except the allocation of range-bw values.
+
+3. Usage
+========
+
+It is very useful to refer the documentation for dm-ioband in
+../../Documentation/device-mapper/ioband.txt or
+
+http://sourceforge.net/apps/trac/ioband/wiki/dm-ioband, because
+Range-BW follows the basic semantics of dm-ioband.
+This example is for range-bw configuration.
+
+# mount the cgroup
+mount -t cgroup -o blkio none /root/cgroup/blkio
+
+# create the process groups (3 groups)
+mkdir /root/cgroup/blkio/bgroup1
+mkdir /root/cgroup/blkio/bgroup2
+mkdir /root/cgroup/blkio/bgroup3
+
+# create the ioband device ( name : ioband1 )
+echo "0 $(blockdev --getsize /dev/sdb2) ioband /dev/sdb2 1 0 0 none
+range-bw 0 :0:0" | dmsetup create ioband1
+: Attention - device name (/dev/sdb2) should be modified depending on
+your system
+
+# init ioband device ( type and policy )
+dmsetup message ioband1 0 type cgroup
+dmsetup message ioband1 0 policy range-bw
+
+# attach the groups to the ioband device
+dmsetup message ioband1 0 attach 2
+dmsetup message ioband1 0 attach 3
+dmsetup message ioband1 0 attach 4
+: group number can be referred in /root/cgroup/blkio/bgroup1/blkio.id
+
+# allocate the values ( range-bw ) : XXX Kbytes
+: the sum of minimum I/O bandwidth in each group should be equal or
+smaller than total bandwidth to be supported by your system
+
+# range : about 100~500 Kbytes
+dmsetup message ioband1 0 range-bw 2:100:500
+
+# range : about 700~1000 Kbytes
+dmsetup message ioband1 0 range-bw 3:700:1000
+
+# range : about 30~35Mbytes
+dmsetup message ioband1 0 range-bw 4:30000:35000
+
+You can confirm the configuration of range-bw by using this command :
+[root@localhost range-bw]# dmsetup table --target ioband
+ioband1: 0 305235000 ioband 8:18 1 4 128 cgroup \
+ range-bw 16384 :0:0 2:100:500 3:700:1000 4:30000:35000
Index: linux-2.6.31/include/trace/events/dm-ioband.h
===================================================================
--- /dev/null
+++ linux-2.6.31/include/trace/events/dm-ioband.h
@@ -0,0 +1,242 @@
+#if !defined(_TRACE_DM_IOBAND_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_DM_IOBAND_H
+
+#include <linux/tracepoint.h>
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM dm-ioband
+
+TRACE_EVENT(ioband_hold_urgent_bio,
+
+ TP_PROTO(struct ioband_group *gp, struct bio *bio),
+
+ TP_ARGS(gp, bio),
+
+ TP_STRUCT__entry(
+ __string( g_name, gp->c_banddev->g_name )
+ __field( int, c_id )
+ __field( int, g_blocked )
+ __field( int, c_blocked )
+ __field( dev_t, dev )
+ __field( sector_t, sector )
+ __field( unsigned int, nr_sector )
+ __field( char, rw )
+ ),
+
+ TP_fast_assign(
+ __assign_str(g_name, gp->c_banddev->g_name);
+ __entry->c_id = gp->c_id;
+ __entry->g_blocked = gp->c_banddev->g_blocked;
+ __entry->c_blocked = gp->c_blocked;
+ __entry->dev = bio->bi_bdev->bd_dev;
+ __entry->sector = bio->bi_sector;
+ __entry->nr_sector = bio->bi_size >> 9;
+ __entry->rw = (bio_data_dir(bio) == READ) ? 'R' : 'W';
+ ),
+
+ TP_printk("%s,%d: %d,%d %c %llu + %u %d %d",
+ __get_str(g_name), __entry->c_id,
+ MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rw,
+ (unsigned long long)__entry->sector,
+ __entry->nr_sector, __entry->g_blocked, __entry->c_blocked)
+);
+
+TRACE_EVENT(ioband_hold_bio,
+
+ TP_PROTO(struct ioband_group *gp, struct bio *bio),
+
+ TP_ARGS(gp, bio),
+
+ TP_STRUCT__entry(
+ __string( g_name, gp->c_banddev->g_name )
+ __field( int, c_id )
+ __field( int, g_blocked )
+ __field( int, c_blocked )
+ __field( dev_t, dev )
+ __field( sector_t, sector )
+ __field( unsigned int, nr_sector )
+ __field( char, rw )
+ ),
+
+ TP_fast_assign(
+ __assign_str(g_name, gp->c_banddev->g_name);
+ __entry->c_id = gp->c_id;
+ __entry->g_blocked = gp->c_banddev->g_blocked;
+ __entry->c_blocked = gp->c_blocked;
+ __entry->dev = bio->bi_bdev->bd_dev;
+ __entry->sector = bio->bi_sector;
+ __entry->nr_sector = bio->bi_size >> 9;
+ __entry->rw = (bio_data_dir(bio) == READ) ? 'R' : 'W';
+ ),
+
+ TP_printk("%s,%d: %d,%d %c %llu + %u %d %d",
+ __get_str(g_name), __entry->c_id,
+ MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rw,
+ (unsigned long long)__entry->sector,
+ __entry->nr_sector, __entry->g_blocked, __entry->c_blocked)
+);
+
+TRACE_EVENT(ioband_make_pback_list,
+
+ TP_PROTO(struct ioband_group *gp, struct bio *bio),
+
+ TP_ARGS(gp, bio),
+
+ TP_STRUCT__entry(
+ __string( g_name, gp->c_banddev->g_name )
+ __field( int, c_id )
+ __field( int, g_blocked )
+ __field( int, c_blocked )
+ __field( dev_t, dev )
+ __field( sector_t, sector )
+ __field( unsigned int, nr_sector )
+ __field( char, rw )
+ ),
+
+ TP_fast_assign(
+ __assign_str(g_name, gp->c_banddev->g_name);
+ __entry->c_id = gp->c_id;
+ __entry->g_blocked = gp->c_banddev->g_blocked;
+ __entry->c_blocked = gp->c_blocked;
+ __entry->dev = bio->bi_bdev->bd_dev;
+ __entry->sector = bio->bi_sector;
+ __entry->nr_sector = bio->bi_size >> 9;
+ __entry->rw = (bio_data_dir(bio) == READ) ? 'R' : 'W';
+ ),
+
+ TP_printk("%s,%d: %d,%d %c %llu + %u %d %d",
+ __get_str(g_name), __entry->c_id,
+ MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rw,
+ (unsigned long long)__entry->sector,
+ __entry->nr_sector, __entry->g_blocked, __entry->c_blocked)
+);
+
+TRACE_EVENT(ioband_make_issue_list,
+
+ TP_PROTO(struct ioband_group *gp, struct bio *bio),
+
+ TP_ARGS(gp, bio),
+
+ TP_STRUCT__entry(
+ __string( g_name, gp->c_banddev->g_name )
+ __field( int, c_id )
+ __field( int, g_blocked )
+ __field( int, c_blocked )
+ __field( dev_t, dev )
+ __field( sector_t, sector )
+ __field( unsigned int, nr_sector )
+ __field( char, rw )
+ ),
+
+ TP_fast_assign(
+ __assign_str(g_name, gp->c_banddev->g_name);
+ __entry->c_id = gp->c_id;
+ __entry->g_blocked = gp->c_banddev->g_blocked;
+ __entry->c_blocked = gp->c_blocked;
+ __entry->dev = bio->bi_bdev->bd_dev;
+ __entry->sector = bio->bi_sector;
+ __entry->nr_sector = bio->bi_size >> 9;
+ __entry->rw = (bio_data_dir(bio) == READ) ? 'R' : 'W';
+ ),
+
+ TP_printk("%s,%d: %d,%d %c %llu + %u %d %d",
+ __get_str(g_name), __entry->c_id,
+ MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rw,
+ (unsigned long long)__entry->sector,
+ __entry->nr_sector, __entry->g_blocked, __entry->c_blocked)
+);
+
+TRACE_EVENT(ioband_release_urgent_bios,
+
+ TP_PROTO(struct ioband_device *dp, struct bio *bio),
+
+ TP_ARGS(dp, bio),
+
+ TP_STRUCT__entry(
+ __string( g_name, dp->g_name )
+ __field( int, g_blocked )
+ __field( dev_t, dev )
+ __field( sector_t, sector )
+ __field( unsigned int, nr_sector )
+ __field( char, rw )
+ ),
+
+ TP_fast_assign(
+ __assign_str(g_name, dp->g_name);
+ __entry->g_blocked = dp->g_blocked;
+ __entry->dev = bio->bi_bdev->bd_dev;
+ __entry->sector = bio->bi_sector;
+ __entry->nr_sector = bio->bi_size >> 9;
+ __entry->rw = (bio_data_dir(bio) == READ) ? 'R' : 'W';
+ ),
+
+ TP_printk("%s: %d,%d %c %llu + %u %d",
+ __get_str(g_name),
+ MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rw,
+ (unsigned long long)__entry->sector,
+ __entry->nr_sector, __entry->g_blocked)
+);
+
+TRACE_EVENT(ioband_make_request,
+
+ TP_PROTO(struct ioband_device *dp, struct bio *bio),
+
+ TP_ARGS(dp, bio),
+
+ TP_STRUCT__entry(
+ __string( g_name, dp->g_name )
+ __field( int, c_id )
+ __field( dev_t, dev )
+ __field( sector_t, sector )
+ __field( unsigned int, nr_sector )
+ __field( char, rw )
+ ),
+
+ TP_fast_assign(
+ __assign_str(g_name, dp->g_name);
+ __entry->dev = bio->bi_bdev->bd_dev;
+ __entry->sector = bio->bi_sector;
+ __entry->nr_sector = bio->bi_size >> 9;
+ __entry->rw = (bio_data_dir(bio) == READ) ? 'R' : 'W';
+ ),
+
+ TP_printk("%s: %d,%d %c %llu + %u",
+ __get_str(g_name),
+ MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rw,
+ (unsigned long long)__entry->sector,
+ __entry->nr_sector)
+);
+
+TRACE_EVENT(ioband_pushback_bio,
+
+ TP_PROTO(struct ioband_device *dp, struct bio *bio),
+
+ TP_ARGS(dp, bio),
+
+ TP_STRUCT__entry(
+ __string( g_name, dp->g_name )
+ __field( dev_t, dev )
+ __field( sector_t, sector )
+ __field( unsigned int, nr_sector )
+ __field( char, rw )
+ ),
+
+ TP_fast_assign(
+ __assign_str(g_name, dp->g_name);
+ __entry->dev = bio->bi_bdev->bd_dev;
+ __entry->sector = bio->bi_sector;
+ __entry->nr_sector = bio->bi_size >> 9;
+ __entry->rw = (bio_data_dir(bio) == READ) ? 'R' : 'W';
+ ),
+
+ TP_printk("%s: %d,%d %c %llu + %u",
+ __get_str(g_name),
+ MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rw,
+ (unsigned long long)__entry->sector,
+ __entry->nr_sector)
+);
+
+#endif /* _TRACE_DM_IOBAND_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
This patch makes the page_cgroup framework be able to be used even if
the compile option of the cgroup memory controller is off.
So blkio-cgroup can use this framework without the memory controller.
Signed-off-by: Hirokazu Takahashi <[email protected]>
Signed-off-by: Ryo Tsuruta <[email protected]>
---
include/linux/memcontrol.h | 6 ++++++
include/linux/mmzone.h | 4 ++--
include/linux/page_cgroup.h | 5 +++--
init/Kconfig | 4 ++++
mm/Makefile | 3 ++-
mm/memcontrol.c | 6 ++++++
mm/page_cgroup.c | 3 +--
7 files changed, 24 insertions(+), 7 deletions(-)
Index: linux-2.6.31/include/linux/memcontrol.h
===================================================================
--- linux-2.6.31.orig/include/linux/memcontrol.h
+++ linux-2.6.31/include/linux/memcontrol.h
@@ -37,6 +37,8 @@ struct mm_struct;
* (Of course, if memcg does memory allocation in future, GFP_KERNEL is sane.)
*/
+extern void __init_mem_page_cgroup(struct page_cgroup *pc);
+
extern int mem_cgroup_newpage_charge(struct page *page, struct mm_struct *mm,
gfp_t gfp_mask);
/* for swap handling */
@@ -121,6 +123,10 @@ void mem_cgroup_update_mapped_file_stat(
#else /* CONFIG_CGROUP_MEM_RES_CTLR */
struct mem_cgroup;
+static inline void __init_mem_page_cgroup(struct page_cgroup *pc)
+{
+}
+
static inline int mem_cgroup_newpage_charge(struct page *page,
struct mm_struct *mm, gfp_t gfp_mask)
{
Index: linux-2.6.31/include/linux/mmzone.h
===================================================================
--- linux-2.6.31.orig/include/linux/mmzone.h
+++ linux-2.6.31/include/linux/mmzone.h
@@ -605,7 +605,7 @@ typedef struct pglist_data {
int nr_zones;
#ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */
struct page *node_mem_map;
-#ifdef CONFIG_CGROUP_MEM_RES_CTLR
+#ifdef CONFIG_CGROUP_PAGE
struct page_cgroup *node_page_cgroup;
#endif
#endif
@@ -956,7 +956,7 @@ struct mem_section {
/* See declaration of similar field in struct zone */
unsigned long *pageblock_flags;
-#ifdef CONFIG_CGROUP_MEM_RES_CTLR
+#ifdef CONFIG_CGROUP_PAGE
/*
* If !SPARSEMEM, pgdat doesn't have page_cgroup pointer. We use
* section. (see memcontrol.h/page_cgroup.h about this.)
Index: linux-2.6.31/include/linux/page_cgroup.h
===================================================================
--- linux-2.6.31.orig/include/linux/page_cgroup.h
+++ linux-2.6.31/include/linux/page_cgroup.h
@@ -1,7 +1,7 @@
#ifndef __LINUX_PAGE_CGROUP_H
#define __LINUX_PAGE_CGROUP_H
-#ifdef CONFIG_CGROUP_MEM_RES_CTLR
+#ifdef CONFIG_CGROUP_PAGE
#include <linux/bit_spinlock.h>
/*
* Page Cgroup can be considered as an extended mem_map.
@@ -14,6 +14,7 @@ struct page_cgroup {
unsigned long flags;
struct mem_cgroup *mem_cgroup;
struct page *page;
+ unsigned long blkio_cgroup_id;
struct list_head lru; /* per cgroup LRU list */
};
@@ -83,7 +84,7 @@ static inline void unlock_page_cgroup(st
bit_spin_unlock(PCG_LOCK, &pc->flags);
}
-#else /* CONFIG_CGROUP_MEM_RES_CTLR */
+#else /* CONFIG_CGROUP_PAGE */
struct page_cgroup;
static inline void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)
Index: linux-2.6.31/init/Kconfig
===================================================================
--- linux-2.6.31.orig/init/Kconfig
+++ linux-2.6.31/init/Kconfig
@@ -614,6 +614,10 @@ config CGROUP_MEM_RES_CTLR_SWAP
endif # CGROUPS
+config CGROUP_PAGE
+ def_bool y
+ depends on CGROUP_MEM_RES_CTLR
+
config MM_OWNER
bool
Index: linux-2.6.31/mm/Makefile
===================================================================
--- linux-2.6.31.orig/mm/Makefile
+++ linux-2.6.31/mm/Makefile
@@ -39,6 +39,7 @@ else
obj-$(CONFIG_SMP) += allocpercpu.o
endif
obj-$(CONFIG_QUICKLIST) += quicklist.o
-obj-$(CONFIG_CGROUP_MEM_RES_CTLR) += memcontrol.o page_cgroup.o
+obj-$(CONFIG_CGROUP_MEM_RES_CTLR) += memcontrol.o
+obj-$(CONFIG_CGROUP_PAGE) += page_cgroup.o
obj-$(CONFIG_DEBUG_KMEMLEAK) += kmemleak.o
obj-$(CONFIG_DEBUG_KMEMLEAK_TEST) += kmemleak-test.o
Index: linux-2.6.31/mm/memcontrol.c
===================================================================
--- linux-2.6.31.orig/mm/memcontrol.c
+++ linux-2.6.31/mm/memcontrol.c
@@ -129,6 +129,12 @@ struct mem_cgroup_lru_info {
struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES];
};
+void __meminit __init_mem_page_cgroup(struct page_cgroup *pc)
+{
+ pc->mem_cgroup = NULL;
+ INIT_LIST_HEAD(&pc->lru);
+}
+
/*
* The memory controller data structure. The memory controller controls both
* page cache and RSS per cgroup. We would eventually like to provide
Index: linux-2.6.31/mm/page_cgroup.c
===================================================================
--- linux-2.6.31.orig/mm/page_cgroup.c
+++ linux-2.6.31/mm/page_cgroup.c
@@ -14,9 +14,8 @@ static void __meminit
__init_page_cgroup(struct page_cgroup *pc, unsigned long pfn)
{
pc->flags = 0;
- pc->mem_cgroup = NULL;
pc->page = pfn_to_page(pfn);
- INIT_LIST_HEAD(&pc->lru);
+ __init_mem_page_cgroup(pc);
}
static unsigned long total_usage;
This patch refactors io_context initialization.
Signed-off-by: Hirokazu Takahashi <[email protected]>
Signed-off-by: Ryo Tsuruta <[email protected]>
---
block/blk-ioc.c | 30 +++++++++++++++++-------------
include/linux/iocontext.h | 1 +
2 files changed, 18 insertions(+), 13 deletions(-)
Index: linux-2.6.31/block/blk-ioc.c
===================================================================
--- linux-2.6.31.orig/block/blk-ioc.c
+++ linux-2.6.31/block/blk-ioc.c
@@ -84,24 +84,28 @@ void exit_io_context(void)
}
}
+void init_io_context(struct io_context *ioc)
+{
+ atomic_long_set(&ioc->refcount, 1);
+ atomic_set(&ioc->nr_tasks, 1);
+ spin_lock_init(&ioc->lock);
+ ioc->ioprio_changed = 0;
+ ioc->ioprio = 0;
+ ioc->last_waited = jiffies; /* doesn't matter... */
+ ioc->nr_batch_requests = 0; /* because this is 0 */
+ ioc->aic = NULL;
+ INIT_RADIX_TREE(&ioc->radix_root, GFP_ATOMIC | __GFP_HIGH);
+ INIT_HLIST_HEAD(&ioc->cic_list);
+ ioc->ioc_data = NULL;
+}
+
struct io_context *alloc_io_context(gfp_t gfp_flags, int node)
{
struct io_context *ret;
ret = kmem_cache_alloc_node(iocontext_cachep, gfp_flags, node);
- if (ret) {
- atomic_long_set(&ret->refcount, 1);
- atomic_set(&ret->nr_tasks, 1);
- spin_lock_init(&ret->lock);
- ret->ioprio_changed = 0;
- ret->ioprio = 0;
- ret->last_waited = jiffies; /* doesn't matter... */
- ret->nr_batch_requests = 0; /* because this is 0 */
- ret->aic = NULL;
- INIT_RADIX_TREE(&ret->radix_root, GFP_ATOMIC | __GFP_HIGH);
- INIT_HLIST_HEAD(&ret->cic_list);
- ret->ioc_data = NULL;
- }
+ if (ret)
+ init_io_context(ret);
return ret;
}
Index: linux-2.6.31/include/linux/iocontext.h
===================================================================
--- linux-2.6.31.orig/include/linux/iocontext.h
+++ linux-2.6.31/include/linux/iocontext.h
@@ -104,6 +104,7 @@ int put_io_context(struct io_context *io
void exit_io_context(void);
struct io_context *get_io_context(gfp_t gfp_flags, int node);
struct io_context *alloc_io_context(gfp_t gfp_flags, int node);
+void init_io_context(struct io_context *ioc);
void copy_io_context(struct io_context **pdst, struct io_context **psrc);
#else
static inline void exit_io_context(void)
The body of blkio-cgroup.
Signed-off-by: Hirokazu Takahashi <[email protected]>
Signed-off-by: Ryo Tsuruta <[email protected]>
---
include/linux/biotrack.h | 100 ++++++++++++++
include/linux/cgroup_subsys.h | 6
init/Kconfig | 13 +
mm/Makefile | 1
mm/biotrack.c | 293 ++++++++++++++++++++++++++++++++++++++++++
mm/page_cgroup.c | 20 +-
6 files changed, 424 insertions(+), 9 deletions(-)
Index: linux-2.6.31/include/linux/biotrack.h
===================================================================
--- /dev/null
+++ linux-2.6.31/include/linux/biotrack.h
@@ -0,0 +1,100 @@
+#include <linux/cgroup.h>
+#include <linux/mm.h>
+#include <linux/page_cgroup.h>
+
+#ifndef _LINUX_BIOTRACK_H
+#define _LINUX_BIOTRACK_H
+
+#ifdef CONFIG_CGROUP_BLKIO
+
+struct io_context;
+struct block_device;
+
+struct blkio_cgroup {
+ struct cgroup_subsys_state css;
+ struct io_context *io_context; /* default io_context */
+/* struct radix_tree_root io_context_root; per device io_context */
+};
+
+/**
+ * __init_blkio_page_cgroup() - initialize a blkio_page_cgroup
+ * @pc: page_cgroup of the page
+ *
+ * Reset the owner ID of a page.
+ */
+static inline void __init_blkio_page_cgroup(struct page_cgroup *pc)
+{
+ pc->blkio_cgroup_id = 0;
+}
+
+/**
+ * blkio_cgroup_disabled() - check whether blkio_cgroup is disabled
+ *
+ * Returns true if disabled, false if not.
+ */
+static inline bool blkio_cgroup_disabled(void)
+{
+ if (blkio_cgroup_subsys.disabled)
+ return true;
+ return false;
+}
+
+extern void blkio_cgroup_set_owner(struct page *page, struct mm_struct *mm);
+extern void blkio_cgroup_reset_owner(struct page *page, struct mm_struct *mm);
+extern void blkio_cgroup_reset_owner_pagedirty(struct page *page,
+ struct mm_struct *mm);
+extern void blkio_cgroup_copy_owner(struct page *page, struct page *opage);
+
+extern struct io_context *get_blkio_cgroup_iocontext(struct bio *bio);
+extern unsigned long get_blkio_cgroup_id(struct bio *bio);
+extern struct cgroup *get_cgroup_from_page(struct page *page);
+
+#else /* !CONFIG_CGROUP_BLKIO */
+
+struct blkio_cgroup;
+
+static inline void __init_blkio_page_cgroup(struct page_cgroup *pc)
+{
+}
+
+static inline bool blkio_cgroup_disabled(void)
+{
+ return true;
+}
+
+static inline void blkio_cgroup_set_owner(struct page *page, struct mm_struct *mm)
+{
+}
+
+static inline void blkio_cgroup_reset_owner(struct page *page,
+ struct mm_struct *mm)
+{
+}
+
+static inline void blkio_cgroup_reset_owner_pagedirty(struct page *page,
+ struct mm_struct *mm)
+{
+}
+
+static inline void blkio_cgroup_copy_owner(struct page *page, struct page *opage)
+{
+}
+
+static inline struct io_context *get_blkio_cgroup_iocontext(struct bio *bio)
+{
+ return NULL;
+}
+
+static inline unsigned long get_blkio_cgroup_id(struct bio *bio)
+{
+ return 0;
+}
+
+static inline struct cgroup *get_cgroup_from_page(struct page *page)
+{
+ return NULL;
+}
+
+#endif /* CONFIG_CGROUP_BLKIO */
+
+#endif /* _LINUX_BIOTRACK_H */
Index: linux-2.6.31/include/linux/cgroup_subsys.h
===================================================================
--- linux-2.6.31.orig/include/linux/cgroup_subsys.h
+++ linux-2.6.31/include/linux/cgroup_subsys.h
@@ -43,6 +43,12 @@ SUBSYS(mem_cgroup)
/* */
+#ifdef CONFIG_CGROUP_BLKIO
+SUBSYS(blkio_cgroup)
+#endif
+
+/* */
+
#ifdef CONFIG_CGROUP_DEVICE
SUBSYS(devices)
#endif
Index: linux-2.6.31/init/Kconfig
===================================================================
--- linux-2.6.31.orig/init/Kconfig
+++ linux-2.6.31/init/Kconfig
@@ -614,9 +614,20 @@ config CGROUP_MEM_RES_CTLR_SWAP
endif # CGROUPS
+config CGROUP_BLKIO
+ bool "Block I/O cgroup subsystem"
+ depends on CGROUPS && BLOCK
+ select MM_OWNER
+ help
+ Provides a Resource Controller which enables to track the onwner
+ of every Block I/O requests.
+ The information this subsystem provides can be used from any
+ kind of module such as dm-ioband device mapper modules or
+ the cfq-scheduler.
+
config CGROUP_PAGE
def_bool y
- depends on CGROUP_MEM_RES_CTLR
+ depends on CGROUP_MEM_RES_CTLR || CGROUP_BLKIO
config MM_OWNER
bool
Index: linux-2.6.31/mm/biotrack.c
===================================================================
--- /dev/null
+++ linux-2.6.31/mm/biotrack.c
@@ -0,0 +1,293 @@
+/* biotrack.c - Block I/O Tracking
+ *
+ * Copyright (C) VA Linux Systems Japan, 2008-2009
+ * Developed by Hirokazu Takahashi <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/smp.h>
+#include <linux/bit_spinlock.h>
+#include <linux/blkdev.h>
+#include <linux/biotrack.h>
+#include <linux/mm_inline.h>
+
+/*
+ * The block I/O tracking mechanism is implemented on the cgroup memory
+ * controller framework. It helps to find the the owner of an I/O request
+ * because every I/O request has a target page and the owner of the page
+ * can be easily determined on the framework.
+ */
+
+/* Return the blkio_cgroup that associates with a cgroup. */
+static inline struct blkio_cgroup *cgroup_blkio(struct cgroup *cgrp)
+{
+ return container_of(cgroup_subsys_state(cgrp, blkio_cgroup_subsys_id),
+ struct blkio_cgroup, css);
+}
+
+/* Return the blkio_cgroup that associates with a process. */
+static inline struct blkio_cgroup *blkio_cgroup_from_task(struct task_struct *p)
+{
+ return container_of(task_subsys_state(p, blkio_cgroup_subsys_id),
+ struct blkio_cgroup, css);
+}
+
+static struct io_context default_blkio_io_context;
+static struct blkio_cgroup default_blkio_cgroup = {
+ .io_context = &default_blkio_io_context,
+};
+
+/**
+ * blkio_cgroup_set_owner() - set the owner ID of a page.
+ * @page: the page we want to tag
+ * @mm: the mm_struct of a page owner
+ *
+ * Make a given page have the blkio-cgroup ID of the owner of this page.
+ */
+void blkio_cgroup_set_owner(struct page *page, struct mm_struct *mm)
+{
+ struct blkio_cgroup *biog;
+ struct page_cgroup *pc;
+
+ if (blkio_cgroup_disabled())
+ return;
+ pc = lookup_page_cgroup(page);
+ if (unlikely(!pc))
+ return;
+
+ pc->blkio_cgroup_id = 0; /* 0: default blkio_cgroup id */
+ if (!mm)
+ return;
+ /*
+ * Locking "pc" isn't necessary here since the current process is
+ * the only one that can access the members related to blkio_cgroup.
+ */
+ rcu_read_lock();
+ biog = blkio_cgroup_from_task(rcu_dereference(mm->owner));
+ if (unlikely(!biog))
+ goto out;
+ /*
+ * css_get(&bio->css) isn't called to increment the reference
+ * count of this blkio_cgroup "biog" so pc->blkio_cgroup_id
+ * might turn invalid even if this page is still active.
+ * This approach is chosen to minimize the overhead.
+ */
+ pc->blkio_cgroup_id = css_id(&biog->css);
+out:
+ rcu_read_unlock();
+}
+
+/**
+ * blkio_cgroup_reset_owner() - reset the owner ID of a page
+ * @page: the page we want to tag
+ * @mm: the mm_struct of a page owner
+ *
+ * Change the owner of a given page if necessary.
+ */
+void blkio_cgroup_reset_owner(struct page *page, struct mm_struct *mm)
+{
+ /*
+ * A little trick:
+ * Just call blkio_cgroup_set_owner() for pages which are already
+ * active since the blkio_cgroup_id member of page_cgroup can be
+ * updated without any locks. This is because an integer type of
+ * variable can be set a new value at once on modern cpus.
+ */
+ blkio_cgroup_set_owner(page, mm);
+}
+
+/**
+ * blkio_cgroup_reset_owner_pagedirty() - reset the owner ID of a pagecache page
+ * @page: the page we want to tag
+ * @mm: the mm_struct of a page owner
+ *
+ * Change the owner of a given page if the page is in the pagecache.
+ */
+void blkio_cgroup_reset_owner_pagedirty(struct page *page, struct mm_struct *mm)
+{
+ if (!page_is_file_cache(page))
+ return;
+ if (current->flags & PF_MEMALLOC)
+ return;
+
+ blkio_cgroup_reset_owner(page, mm);
+}
+
+/**
+ * blkio_cgroup_copy_owner() - copy the owner ID of a page into another page
+ * @npage: the page where we want to copy the owner
+ * @opage: the page from which we want to copy the ID
+ *
+ * Copy the owner ID of @opage into @npage.
+ */
+void blkio_cgroup_copy_owner(struct page *npage, struct page *opage)
+{
+ struct page_cgroup *npc, *opc;
+
+ if (blkio_cgroup_disabled())
+ return;
+ npc = lookup_page_cgroup(npage);
+ if (unlikely(!npc))
+ return;
+ opc = lookup_page_cgroup(opage);
+ if (unlikely(!opc))
+ return;
+
+ /*
+ * Do this without any locks. The reason is the same as
+ * blkio_cgroup_reset_owner().
+ */
+ npc->blkio_cgroup_id = opc->blkio_cgroup_id;
+}
+
+/* Create a new blkio-cgroup. */
+static struct cgroup_subsys_state *
+blkio_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cgrp)
+{
+ struct blkio_cgroup *biog;
+ struct io_context *ioc;
+
+ if (!cgrp->parent) {
+ biog = &default_blkio_cgroup;
+ init_io_context(biog->io_context);
+ /* Increment the referrence count not to be released ever. */
+ atomic_long_inc(&biog->io_context->refcount);
+ return &biog->css;
+ }
+
+ biog = kzalloc(sizeof(*biog), GFP_KERNEL);
+ if (!biog)
+ return ERR_PTR(-ENOMEM);
+ ioc = alloc_io_context(GFP_KERNEL, -1);
+ if (!ioc) {
+ kfree(biog);
+ return ERR_PTR(-ENOMEM);
+ }
+ biog->io_context = ioc;
+ return &biog->css;
+}
+
+/* Delete the blkio-cgroup. */
+static void blkio_cgroup_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp)
+{
+ struct blkio_cgroup *biog = cgroup_blkio(cgrp);
+
+ put_io_context(biog->io_context);
+ free_css_id(&blkio_cgroup_subsys, &biog->css);
+ kfree(biog);
+}
+
+/**
+ * get_blkio_cgroup_id() - determine the blkio-cgroup ID
+ * @bio: the &struct bio which describes the I/O
+ *
+ * Returns the blkio-cgroup ID of a given bio. A return value zero
+ * means that the page associated with the bio belongs to default_blkio_cgroup.
+ */
+unsigned long get_blkio_cgroup_id(struct bio *bio)
+{
+ struct page_cgroup *pc;
+ struct page *page = bio_iovec_idx(bio, 0)->bv_page;
+ unsigned long id = 0;
+
+ pc = lookup_page_cgroup(page);
+ if (pc)
+ id = pc->blkio_cgroup_id;
+ return id;
+}
+
+/**
+ * get_blkio_cgroup_iocontext() - determine the blkio-cgroup iocontext
+ * @bio: the &struct bio which describe the I/O
+ *
+ * Returns the iocontext of blkio-cgroup that issued a given bio.
+ */
+struct io_context *get_blkio_cgroup_iocontext(struct bio *bio)
+{
+ struct cgroup_subsys_state *css;
+ struct blkio_cgroup *biog;
+ struct io_context *ioc;
+ unsigned long id;
+
+ id = get_blkio_cgroup_id(bio);
+ rcu_read_lock();
+ css = css_lookup(&blkio_cgroup_subsys, id);
+ if (css)
+ biog = container_of(css, struct blkio_cgroup, css);
+ else
+ biog = &default_blkio_cgroup;
+ ioc = biog->io_context; /* default io_context for this cgroup */
+ atomic_long_inc(&ioc->refcount);
+ rcu_read_unlock();
+ return ioc;
+}
+
+/**
+ * get_cgroup_from_page() - determine the cgroup from a page.
+ * @page: the page to be tracked
+ *
+ * Returns the cgroup of a given page. A return value zero means that
+ * the page associated with the page belongs to default_blkio_cgroup.
+ *
+ * Note:
+ * This function must be called under rcu_read_lock().
+ */
+struct cgroup *get_cgroup_from_page(struct page *page)
+{
+ struct page_cgroup *pc;
+ struct cgroup_subsys_state *css;
+
+ pc = lookup_page_cgroup(page);
+ if (!pc || !pc->blkio_cgroup_id)
+ return NULL;
+
+ css = css_lookup(&blkio_cgroup_subsys, pc->blkio_cgroup_id);
+ if (!css)
+ return NULL;
+
+ return css->cgroup;
+}
+
+EXPORT_SYMBOL(get_blkio_cgroup_id);
+EXPORT_SYMBOL(get_blkio_cgroup_iocontext);
+EXPORT_SYMBOL(get_cgroup_from_page);
+
+/* Read the ID of the specified blkio cgroup. */
+static u64 blkio_id_read(struct cgroup *cgrp, struct cftype *cft)
+{
+ struct blkio_cgroup *biog = cgroup_blkio(cgrp);
+
+ return (u64)css_id(&biog->css);
+}
+
+static struct cftype blkio_files[] = {
+ {
+ .name = "id",
+ .read_u64 = blkio_id_read,
+ },
+};
+
+static int blkio_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cgrp)
+{
+ return cgroup_add_files(cgrp, ss, blkio_files,
+ ARRAY_SIZE(blkio_files));
+}
+
+struct cgroup_subsys blkio_cgroup_subsys = {
+ .name = "blkio",
+ .create = blkio_cgroup_create,
+ .destroy = blkio_cgroup_destroy,
+ .populate = blkio_cgroup_populate,
+ .subsys_id = blkio_cgroup_subsys_id,
+ .use_id = 1,
+};
Index: linux-2.6.31/mm/page_cgroup.c
===================================================================
--- linux-2.6.31.orig/mm/page_cgroup.c
+++ linux-2.6.31/mm/page_cgroup.c
@@ -9,6 +9,7 @@
#include <linux/vmalloc.h>
#include <linux/cgroup.h>
#include <linux/swapops.h>
+#include <linux/biotrack.h>
static void __meminit
__init_page_cgroup(struct page_cgroup *pc, unsigned long pfn)
@@ -16,6 +17,7 @@ __init_page_cgroup(struct page_cgroup *p
pc->flags = 0;
pc->page = pfn_to_page(pfn);
__init_mem_page_cgroup(pc);
+ __init_blkio_page_cgroup(pc);
}
static unsigned long total_usage;
@@ -73,7 +75,7 @@ void __init page_cgroup_init_flatmem(voi
int nid, fail;
- if (mem_cgroup_disabled())
+ if (mem_cgroup_disabled() && blkio_cgroup_disabled())
return;
for_each_online_node(nid) {
@@ -82,12 +84,13 @@ void __init page_cgroup_init_flatmem(voi
goto fail;
}
printk(KERN_INFO "allocated %ld bytes of page_cgroup\n", total_usage);
- printk(KERN_INFO "please try 'cgroup_disable=memory' option if you"
- " don't want memory cgroups\n");
+ printk(KERN_INFO "please try 'cgroup_disable=memory,blkio' option"
+ " if you don't want memory and blkio cgroups\n");
return;
fail:
printk(KERN_CRIT "allocation of page_cgroup failed.\n");
- printk(KERN_CRIT "please try 'cgroup_disable=memory' boot option\n");
+ printk(KERN_CRIT
+ "please try 'cgroup_disable=memory,blkio' boot option\n");
panic("Out of memory");
}
@@ -244,7 +247,7 @@ void __init page_cgroup_init(void)
unsigned long pfn;
int fail = 0;
- if (mem_cgroup_disabled())
+ if (mem_cgroup_disabled() && blkio_cgroup_disabled())
return;
for (pfn = 0; !fail && pfn < max_pfn; pfn += PAGES_PER_SECTION) {
@@ -253,14 +256,15 @@ void __init page_cgroup_init(void)
fail = init_section_page_cgroup(pfn);
}
if (fail) {
- printk(KERN_CRIT "try 'cgroup_disable=memory' boot option\n");
+ printk(KERN_CRIT
+ "try 'cgroup_disable=memory,blkio' boot option\n");
panic("Out of memory");
} else {
hotplug_memory_notifier(page_cgroup_callback, 0);
}
printk(KERN_INFO "allocated %ld bytes of page_cgroup\n", total_usage);
- printk(KERN_INFO "please try 'cgroup_disable=memory' option if you don't"
- " want memory cgroups\n");
+ printk(KERN_INFO "please try 'cgroup_disable=memory,blkio' option"
+ " if you don't want memory and blkio cgroups\n");
}
void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)
Index: linux-2.6.31/mm/Makefile
===================================================================
--- linux-2.6.31.orig/mm/Makefile
+++ linux-2.6.31/mm/Makefile
@@ -41,5 +41,6 @@ endif
obj-$(CONFIG_QUICKLIST) += quicklist.o
obj-$(CONFIG_CGROUP_MEM_RES_CTLR) += memcontrol.o
obj-$(CONFIG_CGROUP_PAGE) += page_cgroup.o
+obj-$(CONFIG_CGROUP_BLKIO) += biotrack.o
obj-$(CONFIG_DEBUG_KMEMLEAK) += kmemleak.o
obj-$(CONFIG_DEBUG_KMEMLEAK_TEST) += kmemleak-test.o
This patch contains several hooks that let the blkio-cgroup framework to know
which blkio-cgroup is the owner of a page before starting I/O against the page.
Signed-off-by: Hirokazu Takahashi <[email protected]>
Signed-off-by: Ryo Tsuruta <[email protected]>
---
fs/buffer.c | 2 ++
fs/direct-io.c | 2 ++
mm/bounce.c | 2 ++
mm/filemap.c | 2 ++
mm/memory.c | 5 +++++
mm/page-writeback.c | 2 ++
mm/swap_state.c | 2 ++
7 files changed, 17 insertions(+)
Index: linux-2.6.31/fs/buffer.c
===================================================================
--- linux-2.6.31.orig/fs/buffer.c
+++ linux-2.6.31/fs/buffer.c
@@ -36,6 +36,7 @@
#include <linux/buffer_head.h>
#include <linux/task_io_accounting_ops.h>
#include <linux/bio.h>
+#include <linux/biotrack.h>
#include <linux/notifier.h>
#include <linux/cpu.h>
#include <linux/bitops.h>
@@ -668,6 +669,7 @@ static void __set_page_dirty(struct page
if (page->mapping) { /* Race with truncate? */
WARN_ON_ONCE(warn && !PageUptodate(page));
account_page_dirtied(page, mapping);
+ blkio_cgroup_reset_owner_pagedirty(page, current->mm);
radix_tree_tag_set(&mapping->page_tree,
page_index(page), PAGECACHE_TAG_DIRTY);
}
Index: linux-2.6.31/fs/direct-io.c
===================================================================
--- linux-2.6.31.orig/fs/direct-io.c
+++ linux-2.6.31/fs/direct-io.c
@@ -33,6 +33,7 @@
#include <linux/err.h>
#include <linux/blkdev.h>
#include <linux/buffer_head.h>
+#include <linux/biotrack.h>
#include <linux/rwsem.h>
#include <linux/uio.h>
#include <asm/atomic.h>
@@ -797,6 +798,7 @@ static int do_direct_IO(struct dio *dio)
ret = PTR_ERR(page);
goto out;
}
+ blkio_cgroup_reset_owner(page, current->mm);
while (block_in_page < blocks_per_page) {
unsigned offset_in_page = block_in_page << blkbits;
Index: linux-2.6.31/mm/bounce.c
===================================================================
--- linux-2.6.31.orig/mm/bounce.c
+++ linux-2.6.31/mm/bounce.c
@@ -13,6 +13,7 @@
#include <linux/init.h>
#include <linux/hash.h>
#include <linux/highmem.h>
+#include <linux/biotrack.h>
#include <asm/tlbflush.h>
#include <trace/events/block.h>
@@ -210,6 +211,7 @@ static void __blk_queue_bounce(struct re
to->bv_len = from->bv_len;
to->bv_offset = from->bv_offset;
inc_zone_page_state(to->bv_page, NR_BOUNCE);
+ blkio_cgroup_copy_owner(to->bv_page, page);
if (rw == WRITE) {
char *vto, *vfrom;
Index: linux-2.6.31/mm/filemap.c
===================================================================
--- linux-2.6.31.orig/mm/filemap.c
+++ linux-2.6.31/mm/filemap.c
@@ -33,6 +33,7 @@
#include <linux/cpuset.h>
#include <linux/hardirq.h> /* for BUG_ON(!in_atomic()) only */
#include <linux/memcontrol.h>
+#include <linux/biotrack.h>
#include <linux/mm_inline.h> /* for page_is_file_cache() */
#include "internal.h"
@@ -464,6 +465,7 @@ int add_to_page_cache_locked(struct page
gfp_mask & GFP_RECLAIM_MASK);
if (error)
goto out;
+ blkio_cgroup_set_owner(page, current->mm);
error = radix_tree_preload(gfp_mask & ~__GFP_HIGHMEM);
if (error == 0) {
Index: linux-2.6.31/mm/memory.c
===================================================================
--- linux-2.6.31.orig/mm/memory.c
+++ linux-2.6.31/mm/memory.c
@@ -51,6 +51,7 @@
#include <linux/init.h>
#include <linux/writeback.h>
#include <linux/memcontrol.h>
+#include <linux/biotrack.h>
#include <linux/mmu_notifier.h>
#include <linux/kallsyms.h>
#include <linux/swapops.h>
@@ -2116,6 +2117,7 @@ gotten:
*/
ptep_clear_flush_notify(vma, address, page_table);
page_add_new_anon_rmap(new_page, vma, address);
+ blkio_cgroup_set_owner(new_page, mm);
set_pte_at(mm, address, page_table, entry);
update_mmu_cache(vma, address, entry);
if (old_page) {
@@ -2581,6 +2583,7 @@ static int do_swap_page(struct mm_struct
flush_icache_page(vma, page);
set_pte_at(mm, address, page_table, pte);
page_add_anon_rmap(page, vma, address);
+ blkio_cgroup_reset_owner(page, mm);
/* It's better to call commit-charge after rmap is established */
mem_cgroup_commit_charge_swapin(page, ptr);
@@ -2645,6 +2648,7 @@ static int do_anonymous_page(struct mm_s
goto release;
inc_mm_counter(mm, anon_rss);
page_add_new_anon_rmap(page, vma, address);
+ blkio_cgroup_set_owner(page, mm);
set_pte_at(mm, address, page_table, entry);
/* No need to invalidate - it was non-present before */
@@ -2792,6 +2796,7 @@ static int __do_fault(struct mm_struct *
if (anon) {
inc_mm_counter(mm, anon_rss);
page_add_new_anon_rmap(page, vma, address);
+ blkio_cgroup_set_owner(page, mm);
} else {
inc_mm_counter(mm, file_rss);
page_add_file_rmap(page);
Index: linux-2.6.31/mm/page-writeback.c
===================================================================
--- linux-2.6.31.orig/mm/page-writeback.c
+++ linux-2.6.31/mm/page-writeback.c
@@ -23,6 +23,7 @@
#include <linux/init.h>
#include <linux/backing-dev.h>
#include <linux/task_io_accounting_ops.h>
+#include <linux/biotrack.h>
#include <linux/blkdev.h>
#include <linux/mpage.h>
#include <linux/rmap.h>
@@ -1247,6 +1248,7 @@ int __set_page_dirty_nobuffers(struct pa
BUG_ON(mapping2 != mapping);
WARN_ON_ONCE(!PagePrivate(page) && !PageUptodate(page));
account_page_dirtied(page, mapping);
+ blkio_cgroup_reset_owner_pagedirty(page, current->mm);
radix_tree_tag_set(&mapping->page_tree,
page_index(page), PAGECACHE_TAG_DIRTY);
}
Index: linux-2.6.31/mm/swap_state.c
===================================================================
--- linux-2.6.31.orig/mm/swap_state.c
+++ linux-2.6.31/mm/swap_state.c
@@ -18,6 +18,7 @@
#include <linux/pagevec.h>
#include <linux/migrate.h>
#include <linux/page_cgroup.h>
+#include <linux/biotrack.h>
#include <asm/pgtable.h>
@@ -307,6 +308,7 @@ struct page *read_swap_cache_async(swp_e
*/
__set_page_locked(new_page);
SetPageSwapBacked(new_page);
+ blkio_cgroup_set_owner(new_page, current->mm);
err = add_to_swap_cache(new_page, entry, gfp_mask & GFP_KERNEL);
if (likely(!err)) {
/*
The document of blkio-cgroup.
Signed-off-by: Hirokazu Takahashi <[email protected]>
Signed-off-by: Ryo Tsuruta <[email protected]>
---
Documentation/cgroups/00-INDEX | 2 +
Documentation/cgroups/blkio.txt | 49 ++++++++++++++++++++++++++++++++++++++++
2 files changed, 51 insertions(+)
Index: linux-2.6.31/Documentation/cgroups/00-INDEX
===================================================================
--- linux-2.6.31.orig/Documentation/cgroups/00-INDEX
+++ linux-2.6.31/Documentation/cgroups/00-INDEX
@@ -16,3 +16,5 @@ memory.txt
- Memory Resource Controller; design, accounting, interface, testing.
resource_counter.txt
- Resource Counter API.
+blkio.txt
+ - Block I/O Tracking; description, interface and examples.
Index: linux-2.6.31/Documentation/cgroups/blkio.txt
===================================================================
--- /dev/null
+++ linux-2.6.31/Documentation/cgroups/blkio.txt
@@ -0,0 +1,49 @@
+Block I/O Cgroup
+
+1. Overview
+
+Using this feature the owners of any type of I/O can be determined.
+This allows dm-ioband to control block I/O bandwidth even when it is
+accepting delayed write requests. dm-ioband can find the cgroup of
+each request. It is also for possible that others working on I/O
+bandwidth throttling to use this functionality to control asynchronous
+I/O with a little enhancement.
+
+2. Setting up blkio-cgroup
+
+The following kernel config options are required.
+
+CONFIG_CGROUPS=y
+CONFIG_CGROUP_BLKIO=y
+
+Selecting the options for the cgroup memory subsystem is also recommended
+as it makes it possible to give some I/O bandwidth and memory to a selected
+cgroup to control delayed write requests. The amount of dirty pages is
+limited within the cgroup even if the allocated bandwidth is narrow.
+
+CONFIG_RESOURCE_COUNTERS=y
+CONFIG_CGROUP_MEM_RES_CTLR=y
+
+3. User interface
+
+3.1 Mounting the cgroup filesystem
+
+First, mount the cgroup filesystem in order to enable observation and
+modification of the blkio-cgroup settings.
+
+# mount -t cgroup -o blkio none /cgroup
+
+3.2 The blkio.id file
+
+After mounting the cgroup filesystem the blkio.id file will be visible
+in the cgroup directory. This file contains a unique ID number for
+each cgroup. When an I/O operation starts, blkio-cgroup sets the
+page's ID number on the page cgroup. The cgroup of I/O can be
+determined by retrieving the ID number from the page cgroup, because
+the page cgroup is associated with the page which is involved in the
+I/O.
+
+4. Contact
+
+Linux Block I/O Bandwidth Control Project
+http://sourceforge.net/projects/ioband/
With this patch, dm-ioband can work with the blkio-cgroup.
Signed-off-by: Hirokazu Takahashi <[email protected]>
Signed-off-by: Ryo Tsuruta <[email protected]>
---
drivers/md/dm-ioband-ctl.c | 244 ++++++++++++++++++++++++++++++++++++++++-
drivers/md/dm-ioband-policy.c | 20 +++
drivers/md/dm-ioband-rangebw.c | 13 ++
drivers/md/dm-ioband-type.c | 10 -
drivers/md/dm-ioband.h | 18 +++
drivers/md/dm-ioctl.c | 1
include/linux/biotrack.h | 7 +
mm/biotrack.c | 151 +++++++++++++++++++++++++
8 files changed, 453 insertions(+), 11 deletions(-)
Index: linux-2.6.31/include/linux/biotrack.h
===================================================================
--- linux-2.6.31.orig/include/linux/biotrack.h
+++ linux-2.6.31/include/linux/biotrack.h
@@ -9,6 +9,7 @@
struct io_context;
struct block_device;
+struct ioband_cgroup_ops;
struct blkio_cgroup {
struct cgroup_subsys_state css;
@@ -48,6 +49,12 @@ extern void blkio_cgroup_copy_owner(stru
extern struct io_context *get_blkio_cgroup_iocontext(struct bio *bio);
extern unsigned long get_blkio_cgroup_id(struct bio *bio);
extern struct cgroup *get_cgroup_from_page(struct page *page);
+extern int blkio_cgroup_register_ioband(const struct ioband_cgroup_ops *ops);
+
+static inline int blkio_cgroup_unregister_ioband(void)
+{
+ return blkio_cgroup_register_ioband(NULL);
+}
#else /* !CONFIG_CGROUP_BLKIO */
Index: linux-2.6.31/mm/biotrack.c
===================================================================
--- linux-2.6.31.orig/mm/biotrack.c
+++ linux-2.6.31/mm/biotrack.c
@@ -20,6 +20,9 @@
#include <linux/blkdev.h>
#include <linux/biotrack.h>
#include <linux/mm_inline.h>
+#include <linux/seq_file.h>
+#include <linux/dm-ioctl.h>
+#include <../drivers/md/dm-ioband.h>
/*
* The block I/O tracking mechanism is implemented on the cgroup memory
@@ -46,6 +49,8 @@ static struct io_context default_blkio_i
static struct blkio_cgroup default_blkio_cgroup = {
.io_context = &default_blkio_io_context,
};
+static DEFINE_MUTEX(ioband_ops_lock);
+static const struct ioband_cgroup_ops *ioband_ops = NULL;
/**
* blkio_cgroup_set_owner() - set the owner ID of a page.
@@ -181,6 +186,14 @@ blkio_cgroup_create(struct cgroup_subsys
static void blkio_cgroup_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp)
{
struct blkio_cgroup *biog = cgroup_blkio(cgrp);
+ int id;
+
+ mutex_lock(&ioband_ops_lock);
+ if (ioband_ops) {
+ id = css_id(&biog->css);
+ ioband_ops->remove_group(id);
+ }
+ mutex_unlock(&ioband_ops_lock);
put_io_context(biog->io_context);
free_css_id(&blkio_cgroup_subsys, &biog->css);
@@ -258,9 +271,27 @@ struct cgroup *get_cgroup_from_page(stru
return css->cgroup;
}
+/**
+ * blkio_cgroup_register_ioband() - register ioband
+ * @p: a pointer to struct ioband_cgroup_ops
+ *
+ * Calling with NULL means unregistration.
+ * Returns 0 on success.
+ */
+int blkio_cgroup_register_ioband(const struct ioband_cgroup_ops *p)
+{
+ if (blkio_cgroup_disabled())
+ return -1;
+
+ mutex_lock(&ioband_ops_lock);
+ ioband_ops = p;
+ mutex_unlock(&ioband_ops_lock);
+ return 0;
+}
EXPORT_SYMBOL(get_blkio_cgroup_id);
EXPORT_SYMBOL(get_blkio_cgroup_iocontext);
EXPORT_SYMBOL(get_cgroup_from_page);
+EXPORT_SYMBOL(blkio_cgroup_register_ioband);
/* Read the ID of the specified blkio cgroup. */
static u64 blkio_id_read(struct cgroup *cgrp, struct cftype *cft)
@@ -270,11 +301,131 @@ static u64 blkio_id_read(struct cgroup *
return (u64)css_id(&biog->css);
}
+/* Show all ioband devices and their settings. */
+static int blkio_devs_read(struct cgroup *cgrp, struct cftype *cft,
+ struct seq_file *m)
+{
+ mutex_lock(&ioband_ops_lock);
+ if (ioband_ops)
+ ioband_ops->show_device(m);
+ mutex_unlock(&ioband_ops_lock);
+ return 0;
+}
+
+/* Configure ioband devices specified by an ioband device ID */
+static int blkio_devs_write(struct cgroup *cgrp, struct cftype *cft,
+ const char *buffer)
+{
+ char **argv;
+ int argc, r = 0;
+
+ if (cgrp != cgrp->top_cgroup)
+ return -EACCES;
+
+ argv = argv_split(GFP_KERNEL, buffer, &argc);
+ if (!argv)
+ return -ENOMEM;
+
+ mutex_lock(&ioband_ops_lock);
+ if (ioband_ops)
+ r = ioband_ops->config_device(argc, argv);
+ mutex_unlock(&ioband_ops_lock);
+
+ argv_free(argv);
+ return r;
+}
+
+/* Show the information of the specified blkio cgroup. */
+static int blkio_group_read(struct cgroup *cgrp, struct cftype *cft,
+ struct seq_file *m)
+{
+ struct blkio_cgroup *biog;
+ int id;
+
+ mutex_lock(&ioband_ops_lock);
+ if (ioband_ops) {
+ biog = cgroup_blkio(cgrp);
+ id = css_id(&biog->css);
+ ioband_ops->show_group(m, cft->private, id);
+ }
+ mutex_unlock(&ioband_ops_lock);
+ return 0;
+}
+
+/* Configure the specified blkio cgroup. */
+static int blkio_group_config_write(struct cgroup *cgrp, struct cftype *cft,
+ const char *buffer)
+{
+ struct blkio_cgroup *biog;
+ char **argv;
+ int argc, parent, id, r = 0;
+
+ argv = argv_split(GFP_KERNEL, buffer, &argc);
+ if (!argv)
+ return -ENOMEM;
+
+ mutex_lock(&ioband_ops_lock);
+ if (ioband_ops) {
+ if (cgrp == cgrp->top_cgroup)
+ parent = 0;
+ else {
+ biog = cgroup_blkio(cgrp->parent);
+ parent = css_id(&biog->css);
+ }
+ biog = cgroup_blkio(cgrp);
+ id = css_id(&biog->css);
+ r = ioband_ops->config_group(argc, argv, parent, id);
+ }
+ mutex_unlock(&ioband_ops_lock);
+ argv_free(argv);
+ return r;
+}
+
+/* Reset the statictics counter of the specified blkio cgroup. */
+static int blkio_group_stats_write(struct cgroup *cgrp, struct cftype *cft,
+ const char *buffer)
+{
+ struct blkio_cgroup *biog;
+ char **argv;
+ int argc, id, r = 0;
+
+ argv = argv_split(GFP_KERNEL, buffer, &argc);
+ if (!argv)
+ return -ENOMEM;
+
+ mutex_lock(&ioband_ops_lock);
+ if (ioband_ops) {
+ biog = cgroup_blkio(cgrp);
+ id = css_id(&biog->css);
+ r = ioband_ops->reset_group_stats(argc, argv, id);
+ }
+ mutex_unlock(&ioband_ops_lock);
+ argv_free(argv);
+ return r;
+}
+
static struct cftype blkio_files[] = {
{
.name = "id",
.read_u64 = blkio_id_read,
},
+ {
+ .name = "devices",
+ .read_seq_string = blkio_devs_read,
+ .write_string = blkio_devs_write,
+ },
+ {
+ .name = "settings",
+ .read_seq_string = blkio_group_read,
+ .write_string = blkio_group_config_write,
+ .private = IOG_INFO_CONFIG,
+ },
+ {
+ .name = "stats",
+ .read_seq_string = blkio_group_read,
+ .write_string = blkio_group_stats_write,
+ .private = IOG_INFO_STATS,
+ },
};
static int blkio_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cgrp)
Index: linux-2.6.31/drivers/md/dm-ioctl.c
===================================================================
--- linux-2.6.31.orig/drivers/md/dm-ioctl.c
+++ linux-2.6.31/drivers/md/dm-ioctl.c
@@ -1601,3 +1601,4 @@ out:
return r;
}
+EXPORT_SYMBOL(dm_copy_name_and_uuid);
Index: linux-2.6.31/drivers/md/dm-ioband-policy.c
===================================================================
--- linux-2.6.31.orig/drivers/md/dm-ioband-policy.c
+++ linux-2.6.31/drivers/md/dm-ioband-policy.c
@@ -8,6 +8,7 @@
#include <linux/bio.h>
#include <linux/workqueue.h>
#include <linux/rbtree.h>
+#include <linux/seq_file.h>
#include "dm.h"
#include "dm-ioband.h"
@@ -360,7 +361,7 @@ static int policy_weight_param(struct io
if (value)
err = strict_strtol(value, 0, &val);
- if (!strcmp(cmd, "weight")) {
+ if (!cmd || !strcmp(cmd, "weight")) {
if (!value)
r = set_weight(gp, DEFAULT_WEIGHT);
else if (!err && 0 < val && val <= SHORT_MAX)
@@ -425,6 +426,19 @@ static void policy_weight_show(struct io
*szp = sz;
}
+static void policy_weight_show_device(struct seq_file *m,
+ struct ioband_device *dp)
+{
+ seq_printf(m, " token=%d carryover=%d",
+ dp->g_token_bucket, dp->g_carryover);
+}
+
+static void policy_weight_show_group(struct seq_file *m,
+ struct ioband_group *gp)
+{
+ seq_printf(m, " weight=%d%%", gp->c_weight);
+}
+
/*
* <Method> <description>
* g_can_submit : To determine whether a given group has the right to
@@ -453,6 +467,8 @@ static void policy_weight_show(struct io
* Return 1 if a given group can't receive any more BIOs,
* otherwise return 0.
* g_show : Show the configuration.
+ * g_show_device : Show the configuration of the specified ioband device.
+ * g_show_group : Show the configuration of the spacified ioband group.
*/
static int policy_weight_init(struct ioband_device *dp, int argc, char **argv)
{
@@ -475,6 +491,8 @@ static int policy_weight_init(struct iob
dp->g_set_param = policy_weight_param;
dp->g_should_block = is_queue_full;
dp->g_show = policy_weight_show;
+ dp->g_show_device = policy_weight_show_device;
+ dp->g_show_group = policy_weight_show_group;
dp->g_epoch = 0;
dp->g_weight_total = 0;
Index: linux-2.6.31/drivers/md/dm-ioband-rangebw.c
===================================================================
--- linux-2.6.31.orig/drivers/md/dm-ioband-rangebw.c
+++ linux-2.6.31/drivers/md/dm-ioband-rangebw.c
@@ -25,6 +25,7 @@
#include <linux/random.h>
#include <linux/time.h>
#include <linux/timer.h>
+#include <linux/seq_file.h>
#include "dm.h"
#include "md.h"
#include "dm-ioband.h"
@@ -455,7 +456,7 @@ static int policy_range_bw_param(struct
err++;
}
- if (!strcmp(cmd, "range-bw")) {
+ if (!cmd || !strcmp(cmd, "range-bw")) {
if (!err && 0 <= min_val &&
min_val <= (INT_MAX / 2) && 0 <= max_val &&
max_val <= (INT_MAX / 2) && min_val <= max_val)
@@ -543,6 +544,12 @@ static void policy_range_bw_show(struct
*szp = sz;
}
+static void policy_range_bw_show_group(struct seq_file *m,
+ struct ioband_group *gp)
+{
+ seq_printf(m, " range-bw=%d:%d", gp->c_min_bw, gp->c_max_bw);
+}
+
static int range_bw_prepare_token(struct ioband_group *gp,
struct bio *bio, int flag)
{
@@ -629,6 +636,8 @@ static void range_bw_timeover(unsigned l
* Return 1 if a given group can't receive any more BIOs,
* otherwise return 0.
* g_show : Show the configuration.
+ * g_show_device : Show the configuration of the specified ioband device.
+ * g_show_group : Show the configuration of the spacified ioband group.
*/
int policy_range_bw_init(struct ioband_device *dp, int argc, char **argv)
@@ -652,6 +661,8 @@ int policy_range_bw_init(struct ioband_d
dp->g_set_param = policy_range_bw_param;
dp->g_should_block = range_bw_queue_full;
dp->g_show = policy_range_bw_show;
+ dp->g_show_device = NULL;
+ dp->g_show_group = policy_range_bw_show_group;
dp->g_min_bw_total = 0;
dp->g_running_gp = NULL;
Index: linux-2.6.31/drivers/md/dm-ioband-ctl.c
===================================================================
--- linux-2.6.31.orig/drivers/md/dm-ioband-ctl.c
+++ linux-2.6.31/drivers/md/dm-ioband-ctl.c
@@ -15,6 +15,8 @@
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/rbtree.h>
+#include <linux/biotrack.h>
+#include <linux/dm-ioctl.h>
#include "dm.h"
#include "md.h"
#include "dm-ioband.h"
@@ -108,6 +110,7 @@ static struct ioband_device *alloc_ioban
INIT_DELAYED_WORK(&new_dp->g_conductor, ioband_conduct);
INIT_LIST_HEAD(&new_dp->g_groups);
INIT_LIST_HEAD(&new_dp->g_list);
+ INIT_LIST_HEAD(&new_dp->g_heads);
INIT_LIST_HEAD(&new_dp->g_root_groups);
spin_lock_init(&new_dp->g_lock);
bio_list_init(&new_dp->g_urgent_bios);
@@ -242,6 +245,7 @@ static int ioband_group_init(struct ioba
int r;
INIT_LIST_HEAD(&gp->c_list);
+ INIT_LIST_HEAD(&gp->c_heads);
INIT_LIST_HEAD(&gp->c_sibling);
INIT_LIST_HEAD(&gp->c_children);
gp->c_parent = parent;
@@ -282,7 +286,8 @@ static int ioband_group_init(struct ioba
ioband_group_add_node(&head->c_group_root, gp);
gp->c_dev = head->c_dev;
gp->c_target = head->c_target;
- }
+ } else
+ list_add_tail(&gp->c_heads, &dp->g_heads);
spin_unlock_irqrestore(&dp->g_lock, flags);
return 0;
@@ -297,6 +302,8 @@ static void ioband_group_release(struct
list_del(&gp->c_sibling);
if (head)
rb_erase(&gp->c_group_node, &head->c_group_root);
+ else
+ list_del(&gp->c_heads);
dp->g_group_dtr(gp);
kfree(gp);
}
@@ -1334,6 +1341,234 @@ static struct target_type ioband_target
.iterate_devices = ioband_iterate_devices,
};
+#ifdef CONFIG_CGROUP_BLKIO
+/* Copy mapped device name into supplied buffers */
+static void ioband_copy_name(struct ioband_group *gp, char *name)
+{
+ struct mapped_device *md;
+
+ md = dm_table_get_md(gp->c_target->table);
+ dm_copy_name_and_uuid(md, name, NULL);
+ dm_put(md);
+}
+
+/* Show all ioband devices and their settings */
+static void ioband_cgroup_show_device(struct seq_file *m)
+{
+ struct ioband_device *dp;
+ struct ioband_group *head;
+ char name[DM_NAME_LEN];
+
+ mutex_lock(&ioband_lock);
+ list_for_each_entry(dp, &ioband_device_list, g_list) {
+ seq_printf(m, "%s policy=%s io_throttle=%d io_limit=%d",
+ dp->g_name, dp->g_policy->p_name,
+ dp->g_io_throttle, dp->g_io_limit);
+ if (dp->g_show_device)
+ dp->g_show_device(m, dp);
+ seq_putc(m, '\n');
+
+ list_for_each_entry(head, &dp->g_heads, c_heads) {
+ if (strcmp(head->c_type->t_name, "cgroup"))
+ continue;
+ ioband_copy_name(head, name);
+ seq_printf(m, " %s\n", name);
+ }
+ }
+ mutex_unlock(&ioband_lock);
+}
+
+/* Configure the ioband device specified by share name or device name */
+static int ioband_cgroup_config_device(int argc, char **argv)
+{
+ struct ioband_device *dp;
+ struct ioband_group *head;
+ char name[DM_NAME_LEN];
+ int r;
+
+ if (argc < 1)
+ return -EINVAL;
+
+ mutex_lock(&ioband_lock);
+ list_for_each_entry(dp, &ioband_device_list, g_list) {
+ /* lookup by share name */
+ if (!strcmp(dp->g_name, argv[0])) {
+ head = list_first_entry(&dp->g_heads,
+ struct ioband_group, c_heads);
+ goto found;
+ }
+
+ /* lookup by device name */
+ list_for_each_entry(head, &dp->g_heads, c_heads) {
+ ioband_copy_name(head, name);
+ if (!strcmp(name, argv[0]))
+ goto found;
+ }
+ }
+ mutex_unlock(&ioband_lock);
+ return -ENODEV;
+
+found:
+ if (!strcmp(head->c_type->t_name, "cgroup"))
+ r = __ioband_message(head->c_target, --argc, &argv[1]);
+ else
+ r = -ENODEV;
+
+ mutex_unlock(&ioband_lock);
+ return r;
+}
+
+/* Show the settings of the blkio cgroup specified by ID */
+static void ioband_cgroup_show_group(struct seq_file *m, int type, int id)
+{
+ struct ioband_device *dp;
+ struct ioband_group *head, *gp;
+ struct disk_stats *st;
+ char name[DM_NAME_LEN];
+ unsigned long flags;
+
+ mutex_lock(&ioband_lock);
+ list_for_each_entry(dp, &ioband_device_list, g_list) {
+ list_for_each_entry(head, &dp->g_heads, c_heads) {
+ if (strcmp(head->c_type->t_name, "cgroup"))
+ continue;
+
+ gp = (id == 1) ? head : ioband_group_find(head, id);
+ if (!gp)
+ continue;
+
+ ioband_copy_name(head, name);
+ seq_puts(m, name);
+
+ switch (type) {
+ case IOG_INFO_CONFIG:
+ if (dp->g_show_group)
+ dp->g_show_group(m, gp);
+ break;
+ case IOG_INFO_STATS:
+ st = &gp->c_stats;
+ spin_lock_irqsave(&dp->g_lock, flags);
+ seq_printf(m, " %lu %lu %lu %lu"
+ " %lu %lu %lu %lu %d %lu %lu",
+ st->ios[0], st->merges[0],
+ st->sectors[0], st->ticks[0],
+ st->ios[1], st->merges[1],
+ st->sectors[1], st->ticks[1],
+ gp->c_blocked,
+ st->io_ticks, st->time_in_queue);
+ spin_unlock_irqrestore(&dp->g_lock, flags);
+ break;
+ }
+ seq_putc(m, '\n');
+ }
+ }
+ mutex_unlock(&ioband_lock);
+}
+
+/* Configure the blkio cgroup specified by device name and group ID */
+static int ioband_cgroup_config_group(int argc, char **argv,int parent, int id)
+{
+ struct ioband_device *dp;
+ struct ioband_group *head, *gp;
+ char name[DM_NAME_LEN];
+ int r;
+
+ if (argc != 1 && argc != 2)
+ return -EINVAL;
+
+ mutex_lock(&ioband_lock);
+ list_for_each_entry(dp, &ioband_device_list, g_list) {
+ list_for_each_entry(head, &dp->g_heads, c_heads) {
+ if (strcmp(head->c_type->t_name, "cgroup"))
+ continue;
+ ioband_copy_name(head, name);
+ if (!strcmp(name, argv[0]))
+ goto found;
+ }
+ }
+ mutex_unlock(&ioband_lock);
+ return -ENODEV;
+
+found:
+ if (argc == 1) {
+ /* remove the group unless it is not a root cgroup */
+ r = (id == 1) ? -EINVAL : ioband_group_detach(head, id);
+ } else {
+ /* create a group or modify the group settings */
+ gp = (id == 1) ? head : ioband_group_find(head, id);
+
+ if (!gp)
+ r = ioband_group_attach(head, parent, id, argv[1]);
+ else
+ r = gp->c_banddev->g_set_param(gp, NULL, argv[1]);
+ }
+
+ mutex_unlock(&ioband_lock);
+ return r;
+}
+
+/*
+ * Reset the statistics counter of the blkio cgroup specified by
+ * device name and group ID.
+ */
+static int ioband_cgroup_reset_group_stats(int argc, char **argv, int id)
+{
+ struct ioband_device *dp;
+ struct ioband_group *head, *gp;
+ char name[DM_NAME_LEN];
+
+ if (argc != 1)
+ return -EINVAL;
+
+ mutex_lock(&ioband_lock);
+ list_for_each_entry(dp, &ioband_device_list, g_list) {
+ list_for_each_entry(head, &dp->g_heads, c_heads) {
+ if (strcmp(head->c_type->t_name, "cgroup"))
+ continue;
+ ioband_copy_name(head, name);
+ if (strcmp(name, argv[0]))
+ continue;
+
+ gp = (id == 1) ? head : ioband_group_find(head, id);
+ if (gp)
+ memset(&gp->c_stats, 0, sizeof(gp->c_stats));
+
+ mutex_unlock(&ioband_lock);
+ return 0;
+ }
+ }
+ mutex_unlock(&ioband_lock);
+ return -ENODEV;
+}
+
+/* Remove the blkio cgroup specified by ID */
+static void ioband_cgroup_remove_group(int id)
+{
+ struct ioband_device *dp;
+ struct ioband_group *head;
+
+ mutex_lock(&ioband_lock);
+ list_for_each_entry(dp, &ioband_device_list, g_list) {
+ list_for_each_entry(head, &dp->g_heads, c_heads) {
+ if (strcmp(head->c_type->t_name, "cgroup"))
+ continue;
+ if (ioband_group_find(head, id))
+ ioband_group_detach(head, id);
+ }
+ }
+ mutex_unlock(&ioband_lock);
+}
+
+static const struct ioband_cgroup_ops ioband_ops = {
+ .show_device = ioband_cgroup_show_device,
+ .config_device = ioband_cgroup_config_device,
+ .show_group = ioband_cgroup_show_group,
+ .config_group = ioband_cgroup_config_group,
+ .reset_group_stats = ioband_cgroup_reset_group_stats,
+ .remove_group = ioband_cgroup_remove_group,
+};
+#endif
+
static int __init dm_ioband_init(void)
{
int r;
@@ -1341,11 +1576,18 @@ static int __init dm_ioband_init(void)
r = dm_register_target(&ioband_target);
if (r < 0)
DMERR("register failed %d", r);
+#ifdef CONFIG_CGROUP_BLKIO
+ else
+ r = blkio_cgroup_register_ioband(&ioband_ops);
+#endif
return r;
}
static void __exit dm_ioband_exit(void)
{
+#ifdef CONFIG_CGROUP_BLKIO
+ blkio_cgroup_unregister_ioband();
+#endif
dm_unregister_target(&ioband_target);
}
Index: linux-2.6.31/drivers/md/dm-ioband.h
===================================================================
--- linux-2.6.31.orig/drivers/md/dm-ioband.h
+++ linux-2.6.31/drivers/md/dm-ioband.h
@@ -44,6 +44,7 @@ struct ioband_device {
int g_ref;
struct list_head g_list;
+ struct list_head g_heads;
struct list_head g_root_groups;
int g_flags;
char g_name[IOBAND_NAME_MAX + 1];
@@ -60,6 +61,8 @@ struct ioband_device {
int (*g_set_param) (struct ioband_group *, const char *, const char *);
int (*g_should_block) (struct ioband_group *);
void (*g_show) (struct ioband_group *, int *, char *, unsigned);
+ void (*g_show_device) (struct seq_file *, struct ioband_device *);
+ void (*g_show_group) (struct seq_file *, struct ioband_group *);
/* members for weight balancing policy */
int g_epoch;
@@ -99,6 +102,7 @@ struct ioband_device {
struct ioband_group {
struct list_head c_list;
+ struct list_head c_heads;
struct list_head c_sibling;
struct list_head c_children;
struct ioband_group *c_parent;
@@ -150,6 +154,20 @@ struct ioband_group {
};
+struct blkio_cgroup;
+
+struct ioband_cgroup_ops {
+ void (*show_device)(struct seq_file *);
+ int (*config_device)(int, char **);
+ void (*show_group)(struct seq_file *, int, int);
+ int (*config_group)(int, char **, int, int);
+ int (*reset_group_stats)(int, char **, int);
+ void (*remove_group)(int);
+};
+
+#define IOG_INFO_CONFIG 0
+#define IOG_INFO_STATS 1
+
#define IOBAND_URGENT 1
#define DEV_BIO_BLOCKED 1
Index: linux-2.6.31/drivers/md/dm-ioband-type.c
===================================================================
--- linux-2.6.31.orig/drivers/md/dm-ioband-type.c
+++ linux-2.6.31/drivers/md/dm-ioband-type.c
@@ -6,6 +6,7 @@
* This file is released under the GPL.
*/
#include <linux/bio.h>
+#include <linux/biotrack.h>
#include "dm.h"
#include "dm-ioband.h"
@@ -52,14 +53,7 @@ static int ioband_node(struct bio *bio)
static int ioband_cgroup(struct bio *bio)
{
- /*
- * This function should return the ID of the cgroup which
- * issued "bio". The ID of the cgroup which the current
- * process belongs to won't be suitable ID for this purpose,
- * since some BIOs will be handled by kernel threads like aio
- * or pdflush on behalf of the process requesting the BIOs.
- */
- return 0; /* not implemented yet */
+ return get_blkio_cgroup_id(bio);
}
const struct ioband_group_type dm_ioband_group_type[] = {
The document of a cgroup support for dm-ioband.
Signed-off-by: Hirokazu Takahashi <[email protected]>
Signed-off-by: Ryo Tsuruta <[email protected]>
---
Documentation/cgroups/blkio.txt | 314 +++++++++++++++++++++++++++++++++++++++-
1 file changed, 313 insertions(+), 1 deletion(-)
Index: linux-2.6.31/Documentation/cgroups/blkio.txt
===================================================================
--- linux-2.6.31.orig/Documentation/cgroups/blkio.txt
+++ linux-2.6.31/Documentation/cgroups/blkio.txt
@@ -11,6 +11,9 @@ I/O with a little enhancement.
2. Setting up blkio-cgroup
+Note: If dm-ioband is to be used with blkio-cgroup, then the dm-ioband
+patch needs to be applied first.
+
The following kernel config options are required.
CONFIG_CGROUPS=y
@@ -43,7 +46,316 @@ determined by retrieving the ID number f
the page cgroup is associated with the page which is involved in the
I/O.
-4. Contact
+If the dm-ioband support patch was applied then the blkio.devices and
+blkio.settings files will also be present.
+
+4. Using dm-ioband and blkio-cgroup
+
+This section describes how to set up dm-ioband and blkio-cgroup in
+order to control bandwidth on a per cgroup per logical volume basis.
+The example used in this section assumes that there are two LVM volume
+groups on individual hard disks and two logical volumes on each volume
+group.
+
+ Table. LVM configurations
+
+ --------------------------------------------------------------
+ | LVM volume group | vg0 on /dev/sda | vg1 on /dev/sdb |
+ |----------------------+-------------------+-------------------|
+ | LVM logical volume | lv0 | lv1 | lv0 | lv1 |
+ --------------------------------------------------------------
+
+4.1. Creating a dm-ioband logical device
+
+A dm-ioband logical device needs to be created and stacked on the
+device that is to bandwidth controlled. In this example the dm-ioband
+logical devices are stacked on each of the existing LVM logical
+volumes. By using the LVM facilities there is no need to unmount any
+logical volumes, even in the case of a volume being used as the root
+device. The following script is an example of how to stack and remove
+dm-ioband devices.
+
+==================== cut here (ioband.sh) ====================
+#!/bin/sh
+#
+# NOTE: You must run "ioband.sh stop" to restore the device-mapper
+# settings before changing logical volume settings, such as activate,
+# rename, resize and so on. These constraints would be eliminated by
+# enhancing LVM tools to support dm-ioband.
+
+logvols="vg0-lv0 vg0-lv1 vg1-lv0 vg1-lv1"
+
+start()
+{
+ for lv in $logvols; do
+ volgrp=${lv%%-*}
+ orig=${lv}-orig
+
+ # clone an existing logical volume.
+ /sbin/dmsetup table $lv | /sbin/dmsetup create $orig
+
+ # stack a dm-ioband device on the clone.
+ size=$(/sbin/blockdev --getsize /dev/mapper/$orig)
+ cat<<-EOM | /sbin/dmsetup load ${lv}
+ 0 $size ioband /dev/mapper/${orig} ${volgrp} 0 0 cgroup weight 0 :100
+ EOM
+
+ # activate the new setting.
+ /sbin/dmsetup resume $lv
+ done
+}
+
+stop()
+{
+ for lv in $logvols; do
+ orig=${lv}-orig
+
+ # restore the original setting.
+ /sbin/dmsetup table $orig | /sbin/dmsetup load $lv
+
+ # activate the new setting.
+ /sbin/dmsetup resume $lv
+
+ # remove the clone.
+ /sbin/dmsetup remove $orig
+ done
+}
+
+case "$1" in
+ start)
+ start
+ ;;
+ stop)
+ stop
+ ;;
+esac
+exit 0
+==================== cut here (ioband.sh) ====================
+
+The following diagram shows how dm-ioband devices are stacked on and
+removed from the logical volumes.
+
+ Figure. stacking and removing dm-ioband devices
+
+ run "ioband.sh start"
+ ===>
+
+ ----------------------- -----------------------
+ | lv0 | lv1 | | lv0 | lv1 |
+ |(dm-linear)|(dm-linear)| |(dm-ioband)|(dm-ioband)|
+ |-----------------------| |-----------+-----------|
+ | vg0 | | lv0-orig | lv1-orig |
+ ----------------------- |(dm-linear)|(dm-linear)|
+ |-----------------------|
+ | vg0 |
+ -----------------------
+ <===
+ run "ioband.sh stop"
+
+After creating the dm-ioband devices, the settings can be observed by
+reading the blkio.devices file.
+
+# cat /cgroup/blkio.devices
+vg0 policy=weight io_throttle=4 io_limit=192 token=768 carryover=2
+ vg0-lv0
+ vg0-lv1
+vg1 policy=weight io_throttle=4 io_limit=192 token=768 carryover=2
+ vg1-lv0
+ vg1-lv1
+
+The first field in the first line is the symbolic name for an ioband
+device group, and the subsequent fields are settings for the ioband
+device group. The settings can be changed by writing to the
+blkio.devices, for example:
+
+# echo vg1 policy range-bw > /cgroup/blkio.devices
+
+Please refer to Document/device-mapper/ioband.txt which describes the
+details of the ioband device group settings.
+
+The second and the third indented lines "vg0-lv0" and "vg0-lv1" are
+the names of the dm-ioband devices that belong to the ioband device
+group. Typically, dm-ioband devices that reside on the same hard disk
+should belong to the same ioband device group in order to share the
+bandwidth of the hard disk.
+
+dm-ioband is not restricted to working with LVM, it may work in
+conjunction with any type of block device. Please refer to
+Documentation/device-mapper/ioband.txt for more details.
+
+4.2 Setting up dm-ioband through the blkio-cgroup interface
+
+The following table shows the given settings for this example. The
+bandwidth will be assigned on a per cgroup per logical volume basis.
+
+ Table. Settings for each cgroup
+
+ --------------------------------------------------------------
+ | LVM volume group | vg0 on /dev/sda | vg1 on /dev/sdb |
+ |----------------------+-------------------+-------------------|
+ | LVM logical volume | lv0 | lv1 | lv0 | lv1 |
+ |----------------------+-------------------+-------------------|
+ | bandwidth control | relative | absolute |
+ | policy | weight | bandwidth limit |
+ |----------------------+-------------------+-------------------|
+ | unit | weight [%] | throughput [KB/s] |
+ |----------------------+-------------------+-------------------|
+ | settings for cgroup1 | 30 | 50 | 400 | 900 |
+ |----------------------+---------+---------+---------+---------|
+ | settings for cgroup2 | 60 | 20 | 200 | 600 |
+ |----------------------+---------+---------+---------+---------|
+ | for root cgroup | 70 | 30 | 100 | 300 |
+ --------------------------------------------------------------
+
+The set-up is described step-by-step below.
+
+1) Create new cgroups using the mkdir command
+
+# mkdir /cgroup/1
+# mkdir /cgroup/2
+
+2) Set bandwidth control policy on each ioband device group
+
+The set-up of bandwidth control policy is done by writing to
+blkio.devices file.
+
+# echo vg0 policy weight > /cgroup/blkio.devices
+# echo vg1 policy range-bw > /cgroup/blkio.devices
+
+3) Set up the root cgroup
+
+The root cgroup represents the default blkio-cgroup. If an I/O is
+performed by a process in a cgroup and the cgroup is not set up by
+blkio-cgroup, the I/O is charged to the root cgroup.
+
+The set-up of the root cgroup is done by writing to blkio.settings
+file in the cgroup's root directory. The following commands write
+the settings of each logical volume to that file.
+
+# echo vg0-lv0 70 > /cgroup/bklio.settings
+# echo vg0-lv1 30 > /cgroup/bklio.settings
+# echo vg1-lv0 100:100 > /cgroup/blkio.settings
+# echo vg1-lv1 300:300 > /cgroup/blkio.settings
+
+The settings can be verified by reading the blkio.settings file. The
+first field is the symbolic name for an ioband device group, and the
+second field is an ioband device name. The following example shows
+that vg0-lv0 and vg0-lv1 belong to the same ioband device group and
+share the bandwidth of sda according to their weights.
+
+# cat /cgroup/blkio.settings
+sda vg0-lv0 weight=70%
+sda vg0-lv1 weight=30%
+sdb vg1-lv0 range-bw=100:100
+sdb vg1-lv1 range-bw=300:300
+
+4) Set up cgroup1 and cgroup2
+
+New cgroups are set up in the same manner as the root cgroup.
+
+Settings for cgroup1
+# echo vg0-lv0 30 > /cgroup/1/blkio.settings
+# echo vg0-lv1 50 > /cgroup/1/bklio.settings
+# echo vg1-lv0 400:400 > /cgroup/1/blkio.settings
+# echo vg1-lv1 900:900 > /cgroup/1/bklio.settings
+
+Settings for cgroup2
+# echo vg0-lv0 60 > /cgroup/2/blkio.settings
+# echo vg0-lv1 20 > /cgroup/2/bklio.settings
+# echo vg1-lv0 200:200 > /cgroup/2/blkio.settings
+# echo vg1-lv1 600:600 > /cgroup/2/bklio.settings
+
+Again, the settings can be verified by reading the appropriate
+blkio.settings file.
+
+# cat /cgroup/1/blkio.settings
+vg0-lv0 weight=30%
+vg0-lv1 weight=50%
+vg1-lv0 range-bw=400:400
+vg1-lv1 range-bw=900:900
+
+If only the logical volume name is specified, the entry for the
+logical volume is removed.
+
+# echo vg0-lv1 > /cgroup/1/vlkio.setting
+# cat /cgroup/1/blkio.settings
+vg0-lv0 weight=30%
+vg0-lv1 weight=50%
+vg1-lv0 range-bw=400:400
+
+4.3 How bandwidth is distributed in the weight policy.
+
+The weight policy assigns bandwidth proportional to the weight of each
+cgroup in a hierarchical manner. The bandwidth assigned to a parent
+cgroup is distributed among the parent and its children according to
+their weight. For example, if there are two child cgroups under the
+parent cgroup, cgroup1 is assigned 60% of the parent bandwidth, and
+cgroup2 is assigned 30%, then 10% (100% - 60% + 30%) remains for the
+parent cgroup.
+
+ Figure. bandwidth distribution among a parent and children
+
+ (100% - 30% - 60% = 10%)
+ parent
+ / \
+ cgroup1 cgroup2
+ (30%) (60%)
+
+The followings show how the bandwidth is calculated ans assigned to
+each cgroup in the given settings which are shown above.
+
+ Figure. hierarchical settings by the weight policy
+
+ (70%) --- /dev/sda --- (30%)
+
+ vg0/lv0 vg0/lv1
+
+ (10%) (30%)
+ root(parent) root(parent)
+ / \ / \
+ cgroup1 cgroup2 cgroup1 cgroup2
+ (30%) (60%) (50%) (20%)
+
+
+ Table. actual bandwidth assigned to each cgroup
+
+ ------------------------------------------------------------
+ | | | weight | actual bandwidth |
+ | shared | logical | for a root | assigned to each cgroup |
+ | device | volume | group | against /dev/sda |
+ |----------+---------+------------+--------------------------|
+ | | | | parent 70% * 10% = 7% |
+ | | vg0/lv0 | 70% | cgroup1 70% * 30% = 21% |
+ | | | | cgroup2 70% * 60% = 42% |
+ | /dev/sda |---------+------------+--------------------------|
+ | | | | parent 30% * 30% = 9% |
+ | | vg1/lv1 | 30% | cgroup1 30% * 50% = 15% |
+ | | | | cgruop2 30% * 20% = 6% |
+ ------------------------------------------------------------
+
+4.4 Getting IO statistics per cgroup.
+
+The blkio.stats file provides IO statistics per dm-ioband per cgroup.
+This file consists of 12 fields separated by whitespace. The format is
+almost the same as /proc/diskstats and /sys/block/dev/stat files, but
+some fields are reserved for future use and they always return 0.
+
+Field # Name units description
+------- ---- ----- -----------
+1 device name name of dm-ioband device
+2 read I/Os requests number of read I/Os processed
+3 *reserved*
+4 read sectors sectors number of sectors read
+5 *reserved*
+6 write I/Os requests number of write I/Os processed
+7 *reserved*
+8 write sectors sectors number of sectors written
+9 *reserved*
+10 in_flight requests number of I/Os currently in flight
+11 *reserved*
+12 *reserved*
+
+5. Contact
Linux Block I/O Bandwidth Control Project
http://sourceforge.net/projects/ioband/
On Mon, 2009-09-14 at 21:28 +0900, Ryo Tsuruta wrote:
> The list of the patches:
> [PATCH 1/9] I/O bandwidth controller and BIO tracking
> [PATCH 2/9] dm-ioband-1.13.0: All-in-one patch
> [PATCH 3/9] blkio-cgroup-v12: The new page_cgroup framework
> [PATCH 4/9] blkio-cgroup-v12: Refactoring io-context initialization
> [PATCH 5/9] blkio-cgroup-v12: The body of blkio-cgroup
> [PATCH 6/9] blkio-cgroup-v12: Page tracking hooks
> [PATCH 7/9] blkio-cgroup-v12: The document of blkio-cgroup
> [PATCH 8/9] blkio-cgroup-v12: Add a cgroup support to dm-ioband
> [PATCH 9/9] blkio-cgroup-v12: The document of a cgroup support for dm-ioband
Patches 5, 8, and 9 all have checkpatch errors (2 does also but it
involves tracing, so Steven may not let you fix them).
Could you correct those errors before this get included ?
Daniel
Hi Daniel,
Daniel Walker <[email protected]> wrote:
> On Mon, 2009-09-14 at 21:28 +0900, Ryo Tsuruta wrote:
>
> > The list of the patches:
> > [PATCH 1/9] I/O bandwidth controller and BIO tracking
> > [PATCH 2/9] dm-ioband-1.13.0: All-in-one patch
> > [PATCH 3/9] blkio-cgroup-v12: The new page_cgroup framework
> > [PATCH 4/9] blkio-cgroup-v12: Refactoring io-context initialization
> > [PATCH 5/9] blkio-cgroup-v12: The body of blkio-cgroup
> > [PATCH 6/9] blkio-cgroup-v12: Page tracking hooks
> > [PATCH 7/9] blkio-cgroup-v12: The document of blkio-cgroup
> > [PATCH 8/9] blkio-cgroup-v12: Add a cgroup support to dm-ioband
> > [PATCH 9/9] blkio-cgroup-v12: The document of a cgroup support for dm-ioband
>
>
> Patches 5, 8, and 9 all have checkpatch errors (2 does also but it
> involves tracing, so Steven may not let you fix them).
>
> Could you correct those errors before this get included ?
Thank you for checking the patches, I'll fix them by the next post.
Thanks,
Ryo Tsuruta