linux/drivers/md
Mike Snitzer b88efd43f9 dm mpath: delay the requeue of blk-mq requests while all paths down
Return DM_MAPIO_DELAY_REQUEUE from .clone_and_map_rq.  Also, return
false from .busy, if all paths are down, so that blk-mq requests get
mapped via .clone_and_map_rq -- which results in DM_MAPIO_DELAY_REQUEUE
being returned to dm-rq.

This change allows for a noticeable reduction in cpu utilization
(reduced kworker load) while all paths are down, e.g.:

system CPU idleness (as measured by fio's --idle-prof=system):
before: system: 86.58%
after:  system: 98.60%

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
2016-09-15 11:16:17 -04:00
..
bcache bcache: pr_err: more meaningful error message when nr_stripes is invalid 2016-08-18 20:31:03 -07:00
persistent-data dm btree: fix a bug in dm_btree_find_next_single() 2016-07-20 12:43:34 -04:00
bitmap.c md: use bio op accessors 2016-06-07 13:41:38 -06:00
bitmap.h md-cluster: sync bitmap when node received RESYNCING msg 2016-05-04 12:39:35 -07:00
dm-bio-prison.c block: add a bi_error field to struct bio 2015-07-29 08:55:15 -06:00
dm-bio-prison.h dm bio prison: add dm_cell_promote_or_release() 2015-05-29 14:19:06 -04:00
dm-bio-record.h
dm-bufio.c dm: use bio op accessors 2016-06-07 13:41:38 -06:00
dm-bufio.h
dm-builtin.c dm: move request-based code out to dm-rq.[hc] 2016-06-10 15:15:44 -04:00
dm-cache-block-types.h dm cache: revert "remove remainder of distinct discard block size" 2014-11-10 15:25:30 -05:00
dm-cache-metadata.c dm cache metadata: fix cmd_read_lock() acquiring write lock 2016-04-17 11:24:46 -04:00
dm-cache-metadata.h dm cache: make sure every metadata function checks fail_io 2016-03-10 17:12:12 -05:00
dm-cache-policy-cleaner.c - Revert a dm-multipath change that caused a regression for unprivledged 2015-11-04 21:19:53 -08:00
dm-cache-policy-internal.h dm cache: age and write back cache entries even without active IO 2015-06-11 17:13:01 -04:00
dm-cache-policy-smq.c dm cache policy smq: clarify that mq registration failure was for 'mq' 2016-03-10 17:12:11 -05:00
dm-cache-policy.c
dm-cache-policy.h dm cache: age and write back cache entries even without active IO 2015-06-11 17:13:01 -04:00
dm-cache-target.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
dm-core.h dm: move request-based code out to dm-rq.[hc] 2016-06-10 15:15:44 -04:00
dm-crypt.c block, dm-crypt, btrfs: Introduce bio_flags() 2016-09-14 08:48:27 -06:00
dm-delay.c dm: rename target's per_bio_data_size to per_io_data_size 2016-02-22 22:34:37 -05:00
dm-era-target.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
dm-exception-store.c - Revert a dm-multipath change that caused a regression for unprivledged 2015-11-04 21:19:53 -08:00
dm-exception-store.h dm snapshot: fix hung bios when copy error occurs 2016-01-08 20:03:05 -05:00
dm-flakey.c dm flakey: fix reads to be issued if drop_writes configured 2016-08-24 21:55:05 -04:00
dm-io.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
dm-ioctl.c dm: allow bio-based table to be upgraded to bio-based with DAX support 2016-07-20 23:49:52 -04:00
dm-kcopyd.c dm: move request-based code out to dm-rq.[hc] 2016-06-10 15:15:44 -04:00
dm-linear.c libnvdimm for 4.8 2016-07-28 17:38:16 -07:00
dm-log-userspace-base.c dm: drop NULL test before kmem_cache_destroy() and mempool_destroy() 2015-10-31 19:06:00 -04:00
dm-log-userspace-transfer.c dm log userspace transfer: match wait_for_completion_timeout return type 2015-04-15 12:10:20 -04:00
dm-log-userspace-transfer.h
dm-log-writes.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
dm-log.c dm log: fix unitialized bio operation flags 2016-08-24 21:55:05 -04:00
dm-mpath.c dm mpath: delay the requeue of blk-mq requests while all paths down 2016-09-15 11:16:17 -04:00
dm-mpath.h
dm-path-selector.c
dm-path-selector.h dm path selector: remove 'repeat_count' return from .select_path hook 2016-02-22 22:34:42 -05:00
dm-queue-length.c dm path selector: remove 'repeat_count' return from .select_path hook 2016-02-22 22:34:42 -05:00
dm-raid1.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
dm-raid.c dm raid: support raid0 with missing metadata devices 2016-08-17 10:42:39 -04:00
dm-region-hash.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
dm-round-robin.c dm round robin: do not use this_cpu_ptr() without having preemption disabled 2016-08-15 09:23:14 -04:00
dm-rq.c dm rq: introduce dm_mq_kick_requeue_list() 2016-09-15 11:16:05 -04:00
dm-rq.h dm rq: introduce dm_mq_kick_requeue_list() 2016-09-15 11:16:05 -04:00
dm-service-time.c dm path selector: remove 'repeat_count' return from .select_path hook 2016-02-22 22:34:42 -05:00
dm-snap-persistent.c dm: use bio op accessors 2016-06-07 13:41:38 -06:00
dm-snap-transient.c dm snapshot: fix hung bios when copy error occurs 2016-01-08 20:03:05 -05:00
dm-snap.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
dm-stats.c dm: move request-based code out to dm-rq.[hc] 2016-06-10 15:15:44 -04:00
dm-stats.h dm stats: support precise timestamps 2015-06-17 12:40:40 -04:00
dm-stripe.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
dm-switch.c dm switch: simplify conditional in alloc_region_table() 2015-10-31 19:06:06 -04:00
dm-sysfs.c dm: move request-based code out to dm-rq.[hc] 2016-06-10 15:15:44 -04:00
dm-table.c dm error: add DAX support 2016-07-20 23:49:50 -04:00
dm-target.c libnvdimm for 4.8 2016-07-28 17:38:16 -07:00
dm-thin-metadata.c dm thin: fix a race condition between discarding and provisioning a block 2016-07-20 12:43:35 -04:00
dm-thin-metadata.h dm thin: fix a race condition between discarding and provisioning a block 2016-07-20 12:43:35 -04:00
dm-thin.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
dm-uevent.c
dm-uevent.h
dm-verity-fec.c dm verity fec: fix block calculation 2016-07-01 23:29:08 -04:00
dm-verity-fec.h dm verity: add support for forward error correction 2015-12-10 10:39:03 -05:00
dm-verity-target.c dm: rename target's per_bio_data_size to per_io_data_size 2016-02-22 22:34:37 -05:00
dm-verity.h dm verity: add ignore_zero_blocks feature 2015-12-10 10:39:03 -05:00
dm-zero.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
dm.c dm: convert wait loops to use autoremove_wake_function() 2016-09-14 13:56:38 -04:00
dm.h dm: add infrastructure for DAX support 2016-07-20 23:49:49 -04:00
faulty.c MD: rename some functions 2016-01-20 13:52:20 -08:00
Kconfig dm: add missing newline between DM_DEBUG_BLOCK_STACK_TRACING and DM_BUFIO 2016-03-10 17:12:11 -05:00
linear.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
linear.h
Makefile dm: move request-based code out to dm-rq.[hc] 2016-06-10 15:15:44 -04:00
md-cluster.c md-cluster: check the return value of process_recvd_msg 2016-05-09 09:24:04 -07:00
md-cluster.h md-cluster: gather resync infos and enable recv_thread after bitmap is ready 2016-05-09 09:24:03 -07:00
md.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
md.h Merge branch 'mymd/for-next' into mymd/for-linus 2016-07-28 09:34:14 -07:00
multipath.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
multipath.h
raid0.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
raid0.h block: kill merge_bvec_fn() completely 2015-08-13 12:31:57 -06:00
raid1.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
raid1.h md-cluster: Use a small window for resync 2015-10-12 01:32:05 -05:00
raid5-cache.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
raid5.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
raid5.h RAID5: revert e9e4c377e2 to fix a livelock 2016-02-26 09:44:56 -08:00
raid10.c block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
raid10.h raid10: improve random reads performance 2016-07-19 15:20:28 -07:00