Omar Sandoval 81380ca107 blk-mq: use the right hctx when getting a driver tag fails ... While dispatching requests, if we fail to get a driver tag, we mark the hardware queue as waiting for a tag and put the requests on a hctx->dispatch list to be run later when a driver tag is freed. However, blk_mq_dispatch_rq_list() may dispatch requests from multiple hardware queues if using a single-queue scheduler with a multiqueue device. If blk_mq_get_driver_tag() fails, it doesn't update the hardware queue we are processing. This means we end up using the hardware queue of the previous request, which may or may not be the same as that of the current request. If it isn't, the wrong hardware queue will end up waiting for a tag, and the requests will be on the wrong dispatch list, leading to a hang. The fix is twofold: 1. Make sure we save which hardware queue we were trying to get a request for in blk_mq_get_driver_tag() regardless of whether it succeeds or not. 2. Make blk_mq_dispatch_rq_list() take a request_queue instead of a blk_mq_hw_queue to make it clear that it must handle multiple hardware queues, since I've already messed this up on a couple of occasions. This didn't appear in testing with nvme and mq-deadline because nvme has more driver tags than the default number of scheduler tags. However, with the blk_mq_update_nr_hw_queues() fix, it showed up with nbd. Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@fb.com>		2017-04-07 08:56:26 -06:00
..
partitions	partitions/efi: Fix integer overflow in GPT size calculation	2017-01-17 09:02:31 -07:00
Kconfig	virtio, vhost: optimizations, fixes	2017-03-02 13:53:13 -08:00
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: Ensure users for current->bio_list can see the full list.	2017-03-11 15:31:37 -07:00
blk-cgroup.c	sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>	2017-03-02 08:42:32 +01:00
blk-core.c	blk: Ensure users for current->bio_list can see the full list.	2017-03-11 15:31:37 -07:00
blk-exec.c	block: introduce blk_rq_is_passthrough	2017-01-31 14:00:34 -07:00
blk-flush.c	block: don't defer flushes on blk-mq + scheduling	2017-02-17 12:35:47 -07:00
blk-integrity.c	block: Use pointer to backing_dev_info from request_queue	2017-02-02 08:20:48 -07:00
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: don't try Write Same from __blkdev_issue_zeroout	2017-02-06 09:34:46 -07:00
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	block: use same block debugfs directory for blk-mq and blktrace	2017-02-02 10:20:16 -07:00
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: use the right hctx when getting a driver tag fails	2017-04-07 08:56:26 -06:00
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	blk-mq: use the right hctx when getting a driver tag fails	2017-04-07 08:56:26 -06:00
blk-mq.h	blk-mq: use the right hctx when getting a driver tag fails	2017-04-07 08:56:26 -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-stat: fix blk_stat_sum() if all samples are batched	2017-03-16 09:46:14 -06:00
blk-stat.h	block: add scalable completion tracking of requests	2016-11-10 13:53:26 -07:00
blk-sysfs.c	block: don't call ioc_exit_icq() with the queue lock held for blk-mq	2017-03-02 13:59:08 -07:00
blk-tag.c	blk-mq-sched: add framework for MQ capable IO schedulers	2017-01-17 10:04:20 -07:00
blk-throttle.c	scripts/spelling.txt: add "embeded" pattern and fix typo instances	2017-02-27 18:43:47 -08:00
blk-timeout.c	block: remove REQ_NO_TIMEOUT flag	2015-12-22 09:38:34 -07:00
blk-wbt.c	block: Use pointer to backing_dev_info from request_queue	2017-02-02 08:20:48 -07:00
blk-wbt.h	blk-wbt: allow wbt to be enabled always through sysfs	2016-11-28 10:27:03 -07:00
blk-zoned.c	block: Rename blk_queue_zone_size and bdev_zone_size	2017-01-12 07:58:32 -07:00
blk.h	block: optionally merge discontiguous discard bios into a single request	2017-02-08 13:43:08 -07:00
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	Revert "scsi, block: fix duplicate bdi name registration crashes"	2017-03-08 10:55:17 -07:00
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: Consolidate static integrity profile properties	2015-10-21 14:42:38 -06:00