Hi Jens
blk-rq-qos is a standalone framework out of io-sched and can be used to
control or observe the IO progress in block-layer with hooks. blk-rq-qos
is a great design but right now, it is totally fixed and built-in and shut
out peoples who want to use it with external module.
This patchset attempts to make blk-rq-qos framework pluggable and modular.
Then we can update the blk-rq-qos policy module w/o stopping the IO workload.
And it is more convenient to introduce new policy on old machines w/o udgrade
kernel. We can close all of the blk-rq-qos policy if we needn't any of them.
At the moment, the request_queue.rqos list is empty, we needn't to waste cpu
cyles on them.
In addition, a new simple policy is introduced in this patchset which is to
observe the IO statistics per cgroup. A new interface, 'blkio.iostat' is
added into blkio cgroup directories. A very simple tool in following link
https://github.com/jianchwa/iostat-cgrp.git
can be used to output the result in more friendly fashion, such as,
Device DATA IOPS BW RQSZ QLAT DLAT Cgroup
vda R 16.00/s 572.00KB/s 35.75K 9.46us 250.68us test
vdb W 249.00/s 50.34MB/s 207.02K 254.33us 137.41ms
Device META IOPS BW RQSZ QLAT DLAT Cgroup
vdb W 44.00/s 792.00KB/s 18.00K 191.20us 225.25ms
Device DATA IOPS BW RQSZ QLAT DLAT Cgroup
vda R 33.00/s 412.00KB/s 12.48K 8.49us 180.84us test
vdb W 65.00/s 12.71MB/s 200.31K 432.02us 335.31ms
vdb W 38.00/s 12.66MB/s 341.26K 135.56us 230.27ms test
Device META IOPS BW RQSZ QLAT DLAT Cgroup
vda R 5.00/s 68.00KB/s 13.60K 12.51us 162.52us test
vdb W 119.00/s 2.28MB/s 19.63K 10.40ms 149.88ms
Device DATA IOPS BW RQSZ QLAT DLAT Cgroup
vda R 20.00/s 232.00KB/s 11.60K 8.71us 514.30us test
vdb W 183.00/s 35.02MB/s 195.96K 196.82us 129.58ms
vdb W 1.00/s 380.00KB/s 380.00K 48.51us 552.68ms test
As you see, there is device name, meta or data, read or write, cgroup name ,etc.
If there is no cgroup name, it indicates root cgroup which dosn't include
children cgroup's IO. This is different from non-root cgroup.
The 1st patch introduces the general interfaces to make blk-rq-qos pluggable and
modular, such as register/unregister, activate/deactivate, queue sysfs interface.
The 2nd patch make blk-wbt pluggable
The 3rd and 4th patch export some interface which is prepared for following patches
to make iolatency, iocost and ioprio modular
The 5th patch make blk-iolatency pluggable and modular. It has cgroup policy, we
can rmmod it to release a blk cgroup policy slot.
The 6th remove an unused macro
The 7th patch introduce a new macro to control the bio.bi_iocost_cost, this is
also a preparation to make iocost modular.
The 8th patch make iocost pluggable and modular
The 9th patch rename ioprio.c to ioprio-common.c as it has same name with
following ioprio.ko in Makefilea
The 10th patch make ioprio policy pluggable and modular
The 11th patch remove some unused interfaces of blk-rq-qos.c, such as
rq_qos_add/del
The 12th patch make request carry blkcg_gq, this is needned by the following
iostat policy.
The 13th patch introduce the iostat policy of blk-rq-qos.
Wang Jianchao (13)
blk: make blk-rq-qos support pluggable and modular policy
blk-wbt: make wbt pluggable
blk: export following interfaces
cgroup: export following two interfaces
blk-iolatency: make iolatency pluggable and modular
blk: remove unused BLK_RQ_IO_DATA_LEN
blk: use standalone macro to control bio.bi_iocost_cost
blk-iocost: make iocost pluggable and modular
blk: rename ioprio.c to ioprio-common.c
blk-ioprio: make ioprio pluggable and modular
blk: remove unused interfaces of blk-rq-qos
blk: make request able to carry blkcg_gq
blk: introduce iostat per cgroup module
block/Kconfig | 23 ++++-
block/Makefile | 13 ++-
block/bdev.c | 5 -
block/bio.c | 2 +-
block/blk-cgroup.c | 23 +++--
block/blk-core.c | 6 +-
block/blk-iocost.c | 53 ++++++----
block/blk-iolatency.c | 39 +++++--
block/blk-ioprio.c | 50 ++++++---
block/blk-ioprio.h | 19 ----
block/blk-iostat.c | 347 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
block/blk-merge.c | 9 ++
block/blk-mq-debugfs.c | 22 +---
block/blk-mq.c | 14 +++
block/blk-rq-qos.c | 4 +-
block/blk-rq-qos.h | 67 +-----------
block/blk-stat.c | 30 ------
block/blk-stat.h | 31 +++++-
block/blk-sysfs.c | 7 +-
block/blk-wbt.c | 30 +++++-
block/blk-wbt.h | 8 +-
block/blk.h | 6 --
block/{ioprio.c => ioprio-common.c} | 0
include/linux/blk-cgroup.h | 1 +
include/linux/blk-mq.h | 4 +-
include/linux/blk_types.h | 2 +-
include/linux/blkdev.h | 7 +-
include/linux/cgroup.h | 5 +-
kernel/cgroup/cgroup.c | 7 ++
29 files changed, 599 insertions(+), 235 deletions(-)
