linux/block
Tejun Heo 60a837077e cfq-iosched: charge async IOs to the appropriate blkcg's instead of the root
Up until now, all async IOs were queued to async queues which are
shared across the whole request_queue, which means that blkcg resource
control is completely void on async IOs including all writeback IOs.
It was done this way because writeback didn't support writeback and
there was no way of telling which writeback IO belonged to which
cgroup; however, writeback recently became cgroup aware and writeback
bio's are sent down properly tagged with the blkcg's to charge them
against.

This patch makes async cfq_queues per-cfq_cgroup instead of
per-cfq_data so that each async IO is charged to the blkcg that it was
tagged for instead of unconditionally attributing it to root.

* cfq_data->async_cfqq and ->async_idle_cfqq are moved to cfq_group
  and alloc / destroy paths are updated accordingly.

* cfq_link_cfqq_cfqg() no longer overrides @cfqg to root for async
  queues.

* check_blkcg_changed() now also invalidates async queues as they no
  longer stay the same across cgroups.

After this patch, cfq's proportional IO control through blkio.weight
works correctly when cgroup writeback is in use.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Arianna Avanzini <avanzini.arianna@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-18 15:49:16 -07:00
..
partitions Merge branch 'for-3.20/core' of git://git.kernel.dk/linux-block 2015-02-12 14:13:23 -08:00
bio-integrity.c bio integrity: do not assume bio_integrity_pool exists if bioset exists 2015-07-07 07:46:47 -06:00
bio.c block: Do a full clone when splitting discard bios 2015-07-23 16:21:34 -06:00
blk-cgroup.c blkcg, cfq-iosched: use GFP_NOWAIT instead of GFP_ATOMIC for non-critical allocations 2015-08-18 15:49:16 -07:00
blk-core.c block: use FIELD_SIZEOF to calculate size of a field 2015-07-07 07:47:37 -06:00
blk-exec.c block: move PM request support to IDE 2015-05-05 13:40:42 -06:00
blk-flush.c blk-mq: support per-distpatch_queue flush machinery 2014-09-25 15:22:45 -06:00
blk-integrity.c writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
blk-ioc.c block: Substitute rcu_access_pointer() for rcu_dereference_raw() 2014-02-18 12:21:26 -08:00
blk-iopoll.c Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next 2014-06-03 12:57:53 -07:00
blk-lib.c block: Quiesce zeroout wrapper 2015-02-05 10:14:54 -07:00
blk-map.c blk_rq_map_user(): use import_single_range() 2015-04-11 22:27:13 -04:00
blk-merge.c block: only honor SG gap prevention for merges that contain data 2015-05-29 13:10:23 -06:00
blk-mq-cpu.c blk-mq: add file comments and update copyright notices 2014-05-28 10:15:41 -06:00
blk-mq-cpumap.c sched/topology: Rename topology_thread_cpumask() to topology_sibling_cpumask() 2015-05-27 15:22:15 +02:00
blk-mq-sysfs.c blk-mq: add blk_mq_init_allocated_queue and export blk_mq_register_disk 2015-03-13 08:26:53 -06:00
blk-mq-tag.c blk-mq: Shared tag enhancements 2015-06-01 14:35:56 -06:00
blk-mq-tag.h blk-mq: Shared tag enhancements 2015-06-01 14:35:56 -06:00
blk-mq.c blk-mq: set default timeout as 30 seconds 2015-07-16 08:39:11 -06:00
blk-mq.h blk-mq: release mq's kobjects in blk_release_queue() 2015-01-29 08:30:51 -08:00
blk-settings.c block: fix blk_stack_limits() regression due to lcm() change 2015-03-31 09:45:50 -06:00
blk-softirq.c block: fix regression with block enabled tagging 2014-04-09 21:54:06 -06:00
blk-sysfs.c Merge branch 'for-4.2/writeback' of git://git.kernel.dk/linux-block 2015-06-25 16:00:17 -07:00
blk-tag.c block: support different tag allocation policy 2015-01-23 14:15:46 -07:00
blk-throttle.c blkcg: move block/blk-cgroup.h to include/linux/blk-cgroup.h 2015-06-02 08:33:33 -06:00
blk-timeout.c blk-mq: Allow requests to never expire 2015-01-08 08:59:01 -07:00
blk.h blk-mq: make plug work for mutiple disks and queues 2015-05-08 14:17:23 -06:00
bounce.c Merge branch 'for-4.2/writeback' of git://git.kernel.dk/linux-block 2015-06-25 16:00:17 -07:00
bsg-lib.c bsg: Remove unused function bsg_goose_queue() 2012-12-06 14:33:02 +01:00
bsg.c block: Simplify bsg complete all 2015-02-04 09:57:52 -07:00
cfq-iosched.c cfq-iosched: charge async IOs to the appropriate blkcg's instead of the root 2015-08-18 15:49:16 -07:00
cmdline-parser.c block: remove unrelated header files and export symbol 2014-01-21 20:18:26 -08:00
compat_ioctl.c block, bdi: an active gendisk always has a request_queue associated with it 2014-09-08 10:00:35 -06:00
deadline-iosched.c block: Stop abusing csd.list for fifo_time 2014-02-24 14:46:32 -08:00
elevator.c Merge branch 'for-4.2/writeback' of git://git.kernel.dk/linux-block 2015-06-25 16:00:17 -07:00
genhd.c Merge branch 'for-4.2/writeback' of git://git.kernel.dk/linux-block 2015-06-25 16:00:17 -07:00
ioctl.c block: replace trylock with mutex_lock in blkdev_reread_part() 2015-05-20 09:05:45 -06:00
ioprio.c block: Fix computation of merged request priority 2014-10-31 08:30:43 -06:00
Kconfig block: Add T10 Protection Information functions 2014-09-27 09:14:59 -06:00
Kconfig.iosched blkcg: make CONFIG_BLK_CGROUP bool 2012-03-06 21:27:21 +01:00
Makefile block: Add T10 Protection Information functions 2014-09-27 09:14:59 -06:00
noop-iosched.c elevator: Fix a race in elevator switching 2013-07-03 13:25:24 +02:00
partition-generic.c block: Fix dev_t minor allocation lifetime 2014-09-03 15:01:02 -06:00
scsi_ioctl.c block: fix bogus EFAULT error from SG_IO ioctl 2015-06-27 11:43:34 -06:00
t10-pi.c block: Add T10 Protection Information functions 2014-09-27 09:14:59 -06:00