Tahsin Erdogan 7fc6b87a9f blkcg: allocate struct blkcg_gq outside request queue spinlock ... blkg_conf_prep() currently calls blkg_lookup_create() while holding request queue spinlock. This means allocating memory for struct blkcg_gq has to be made non-blocking. This causes occasional -ENOMEM failures in call paths like below: pcpu_alloc+0x68f/0x710 __alloc_percpu_gfp+0xd/0x10 __percpu_counter_init+0x55/0xc0 cfq_pd_alloc+0x3b2/0x4e0 blkg_alloc+0x187/0x230 blkg_create+0x489/0x670 blkg_lookup_create+0x9a/0x230 blkg_conf_prep+0x1fb/0x240 __cfqg_set_weight_device.isra.105+0x5c/0x180 cfq_set_weight_on_dfl+0x69/0xc0 cgroup_file_write+0x39/0x1c0 kernfs_fop_write+0x13f/0x1d0 __vfs_write+0x23/0x120 vfs_write+0xc2/0x1f0 SyS_write+0x44/0xb0 entry_SYSCALL_64_fastpath+0x18/0xad In the code path above, percpu allocator cannot call vmalloc() due to queue spinlock. A failure in this call path gives grief to tools which are trying to configure io weights. We see occasional failures happen shortly after reboots even when system is not under any memory pressure. Machines with a lot of cpus are more vulnerable to this condition. Update blkg_create() function to temporarily drop the rcu and queue locks when it is allowed by gfp mask. Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Tahsin Erdogan <tahsin@google.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@fb.com>		2017-03-28 15:59:04 -06:00
..
partitions	partitions/efi: Fix integer overflow in GPT size calculation	2017-01-17 09:02:31 -07:00
Kconfig	blk-throttle: add configure option for new .low interface	2017-03-28 08:02:20 -06:00
Kconfig.iosched	block: get rid of blk-mq default scheduler choice Kconfig entries	2017-02-22 13:19:45 -07:00
Makefile	virtio, vhost: optimizations, fixes	2017-03-02 13:53:13 -08:00
badblocks.c	badblocks: badblocks_set/clear update unacked_exist	2016-10-21 15:45:47 -06:00
bio-integrity.c	block: remove bio_is_rw	2016-10-28 08:45:17 -06:00
bio.c	blk-throttle: add a simple idle detection	2017-03-28 08:02:20 -06:00
blk-cgroup.c	blkcg: allocate struct blkcg_gq outside request queue spinlock	2017-03-28 15:59:04 -06:00
blk-core.c	block: track request size in blk_issue_stat	2017-03-28 08:02:20 -06:00
blk-exec.c	block: introduce blk_rq_is_passthrough	2017-01-31 14:00:34 -07:00
blk-flush.c	block: remove outdated part of blkdev_issue_flush() comment	2017-03-24 15:41:30 -06:00
blk-integrity.c	block: constify struct blk_integrity_profile	2017-03-24 20:34:39 -06:00
blk-ioc.c	Merge branch 'for-linus' of git://git.kernel.dk/linux-block	2017-03-03 10:53:35 -08:00
blk-lib.c	block: correct documentation for blkdev_issue_discard() flags	2017-03-24 15:41:28 -06:00
blk-map.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>	2017-03-02 08:42:36 +01:00
blk-merge.c	block: optionally merge discontiguous discard bios into a single request	2017-02-08 13:43:08 -07:00
blk-mq-cpumap.c	blk-mq: export blk_mq_map_queues	2016-11-08 17:30:00 -05:00
blk-mq-debugfs.c	blk-stat: convert to callback-based statistics reporting	2017-03-21 10:03:11 -06:00
blk-mq-pci.c	blk_mq: linux/blk-mq.h does not include all the headers it depends on	2016-09-19 08:21:51 -06:00
blk-mq-sched.c	blk-mq: move update of tags->rqs to __blk_mq_alloc_request()	2017-03-02 08:56:04 -07:00
blk-mq-sched.h	blk-mq-sched: separate mark hctx and queue restart operations	2017-02-23 11:55:47 -07:00
blk-mq-sysfs.c	blk-mq: free hctx->cpumask in release handler of hctx's kobject	2017-03-08 09:56:12 -07:00
blk-mq-tag.c	blk-mq: Fix tagset reinit in the presence of cpu hot-unplug	2017-03-13 08:14:23 -06:00
blk-mq-tag.h	blk-mq-sched: Allocate sched reserved tags as specified in the original queue tagset	2017-03-02 08:56:04 -07:00
blk-mq-virtio.c	blk-mq: provide a default queue mapping for virtio device	2017-02-27 20:54:05 +02:00
blk-mq.c	block: track request size in blk_issue_stat	2017-03-28 08:02:20 -06:00
blk-mq.h	blk-stat: convert to callback-based statistics reporting	2017-03-21 10:03:11 -06:00
blk-settings.c	block: optionally merge discontiguous discard bios into a single request	2017-02-08 13:43:08 -07:00
blk-softirq.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/topology.h>	2017-03-02 08:42:26 +01:00
blk-stat.c	blk-throttle: add a mechanism to estimate IO latency	2017-03-28 08:02:20 -06:00
blk-stat.h	blk-throttle: add a mechanism to estimate IO latency	2017-03-28 08:02:20 -06:00
blk-sysfs.c	blk-throttle: choose a small throtl_slice for SSD	2017-03-28 08:02:20 -06:00
blk-tag.c	blk-mq-sched: add framework for MQ capable IO schedulers	2017-01-17 10:04:20 -07:00
blk-throttle.c	blk-throttle: add latency target support	2017-03-28 08:02:20 -06:00
blk-timeout.c	block: remove REQ_NO_TIMEOUT flag	2015-12-22 09:38:34 -07:00
blk-wbt.c	blk-stat: convert to callback-based statistics reporting	2017-03-21 10:03:11 -06:00
blk-wbt.h	block: track request size in blk_issue_stat	2017-03-28 08:02:20 -06:00
blk-zoned.c	block: Rename blk_queue_zone_size and bdev_zone_size	2017-01-12 07:58:32 -07:00
blk.h	blk-throttle: add a mechanism to estimate IO latency	2017-03-28 08:02:20 -06:00
bounce.c	Merge branch 'for-linus' of git://git.kernel.dk/linux-block	2015-09-19 18:57:09 -07:00
bsg-lib.c	block: split scsi_request out of struct request	2017-01-27 15:08:35 -07:00
bsg.c	lib/vsprintf.c: remove %Z support	2017-02-27 18:43:47 -08:00
cfq-iosched.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/clock.h>	2017-03-02 08:42:27 +01:00
cmdline-parser.c	block: remove unrelated header files and export symbol	2014-01-21 20:18:26 -08:00
compat_ioctl.c	block: Get rid of blk_get_backing_dev_info()	2017-02-02 08:21:32 -07:00
deadline-iosched.c	block: enumify ELEVATOR_*_MERGE	2017-02-08 13:43:06 -07:00
elevator.c	block: don't call ioc_exit_icq() with the queue lock held for blk-mq	2017-03-02 13:59:08 -07:00
genhd.c	block: Fix oops scsi_disk_get()	2017-03-22 20:11:37 -06:00
ioctl.c	block: Get rid of blk_get_backing_dev_info()	2017-02-02 08:21:32 -07:00
ioprio.c	sched/headers: Prepare to move the task_lock()/unlock() APIs to <linux/sched/task.h>	2017-03-02 08:42:38 +01:00
mq-deadline.c	block: enumify ELEVATOR_*_MERGE	2017-02-08 13:43:06 -07:00
noop-iosched.c	block: move existing elevator ops to union	2017-01-17 10:03:33 -07:00
opal_proto.h	block/sed-opal: allocate struct opal_dev dynamically	2017-02-17 12:41:47 -07:00
partition-generic.c	block: Rename blk_queue_zone_size and bdev_zone_size	2017-01-12 07:58:32 -07:00
scsi_ioctl.c	block: fold cmd_type into the REQ_OP_ space	2017-01-31 14:00:44 -07:00
sed-opal.c	block/sed: Fix opal user range check and unused variables	2017-03-08 09:56:12 -07:00
t10-pi.c	block: constify struct blk_integrity_profile	2017-03-24 20:34:39 -06:00