Yuanhan Liu b1b4648648 md/raid5: split wait_for_stripe and introduce wait_for_quiescent ... I noticed heavy spin lock contention at get_active_stripe(), introduced at being wake up stage, where a bunch of processes try to re-hold the spin lock again. After giving some thoughts on this issue, I found the lock could be relieved(and even avoided) if we turn the wait_for_stripe to per waitqueue for each lock hash and make the wake up exclusive: wake up one process each time, which avoids the lock contention naturally. Before go hacking with wait_for_stripe, I found it actually has 2 usages: for the array to enter or leave the quiescent state, and also to wait for an available stripe in each of the hash lists. So this patch splits the first usage off into a separate wait_queue, wait_for_quiescent, and the next patch will turn the second usage into one waitqueue for each hash value, and make it exclusive, to relieve the lock contention. v2: wake_up(wait_for_quiescent) when (active_stripes == 0) Commit log refactor suggestion from Neil. Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Signed-off-by: NeilBrown <neilb@suse.de>		2015-06-17 10:00:21 +10:00
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bcache	md/bcache: use generic io stats accounting functions to simplify io stat accounting	2014-11-24 08:05:12 -07:00
persistent-data	- Significant dm-crypt CPU scalability performance improvements thanks	2015-02-21 13:28:45 -08:00
bitmap.c	md/bitmap: remove rcu annotation from pointer arithmetic.	2015-05-21 09:14:41 +10:00
bitmap.h	md-cluster: re-add capabilities	2015-04-22 07:59:39 +10:00
dm-bio-prison.c	dm bio prison: introduce support for locking ranges of blocks	2014-11-10 15:25:30 -05:00
dm-bio-prison.h	dm bio prison: introduce support for locking ranges of blocks	2014-11-10 15:25:30 -05:00
dm-bio-record.h	dm: Refactor for new bio cloning/splitting	2013-11-23 22:33:55 -08:00
dm-bufio.c	dm bufio: fix time comparison to use time_after_eq()	2015-02-09 13:06:48 -05:00
dm-bufio.h	dm snapshot: use dm-bufio prefetch	2014-01-14 23:23:03 -05:00
dm-builtin.c	dm sysfs: fix a module unload race	2014-01-14 23:23:04 -05:00
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: fix missing ERR_PTR returns and handling	2015-01-28 09:59:20 -05:00
dm-cache-metadata.h	dm cache: revert "remove remainder of distinct discard block size"	2014-11-10 15:25:30 -05:00
dm-cache-policy-cleaner.c
dm-cache-policy-internal.h	dm cache: add remove_cblock method to policy interface	2013-11-11 11:37:50 -05:00
dm-cache-policy-mq.c	dm cache policy mq: try not to writeback data that changed in the last second	2015-03-31 12:03:48 -04:00
dm-cache-policy.c	dm cache: add policy name to status output	2014-01-16 13:44:11 -05:00
dm-cache-policy.h	dm cache: add policy name to status output	2014-01-16 13:44:11 -05:00
dm-cache-target.c	- Most significant change this cycle is request-based DM now supports	2015-02-12 16:36:31 -08:00
dm-crypt.c	Revert "dm crypt: fix deadlock when async crypto algorithm returns -EBUSY"	2015-05-05 12:16:43 -04:00
dm-delay.c	dm delay: use msecs_to_jiffies for time conversion	2015-04-15 12:10:21 -04:00
dm-era-target.c	dm era: check for a non-NULL metadata object before closing it	2014-06-03 13:44:08 -04:00
dm-exception-store.c
dm-exception-store.h
dm-flakey.c	block: Abstract out bvec iterator	2013-11-23 22:33:47 -08:00
dm-io.c	dm io: deal with wandering queue limits when handling REQ_DISCARD and REQ_WRITE_SAME	2015-02-27 14:53:32 -05:00
dm-ioctl.c	dm: only initialize the request_queue once	2015-04-30 10:25:21 -04:00
dm-kcopyd.c
dm-linear.c	block: Abstract out bvec iterator	2013-11-23 22:33:47 -08:00
dm-log-userspace-base.c	dm log userspace base: fix compile warning	2015-04-15 12:10:20 -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	dm: add log writes target	2015-04-15 12:10:24 -04:00
dm-log.c
dm-mpath.c	dm mpath: fix leak of dm_mpath_io structure in blk-mq .queue_rq error path	2015-05-27 17:37:22 -04:00
dm-mpath.h
dm-path-selector.c
dm-path-selector.h
dm-queue-length.c
dm-raid.c	- Most significant change this cycle is request-based DM now supports	2015-02-12 16:36:31 -08:00
dm-raid1.c	dm mirror: do not degrade the mirror on discard error	2015-02-13 19:50:46 -05:00
dm-region-hash.c	block: Abstract out bvec iterator	2013-11-23 22:33:47 -08:00
dm-round-robin.c
dm-service-time.c
dm-snap-persistent.c	dm snapshot: remove unnecessary NULL checks before vfree() calls	2015-02-09 13:06:49 -05:00
dm-snap-transient.c
dm-snap.c	dm snapshot: suspend merging snapshot when doing exception handover	2015-02-27 14:53:16 -05:00
dm-stats.c	- Significant DM thin-provisioning performance improvements to meet	2014-12-08 21:10:03 -08:00
dm-stats.h
dm-stripe.c	dm stripe: fix potential for leak in stripe_ctr error path	2014-10-10 22:05:18 -04:00
dm-switch.c	dm switch: efficiently support repetitive patterns	2014-08-01 12:30:37 -04:00
dm-sysfs.c	dm: add 'use_blk_mq' module param and expose in per-device ro sysfs attr	2015-04-15 12:10:17 -04:00
dm-table.c	dm: fix reload failure of 0 path multipath mapping on blk-mq devices	2015-05-29 13:41:16 -04:00
dm-target.c	dm: allocate requests in target when stacking on blk-mq devices	2015-02-09 13:06:47 -05:00
dm-thin-metadata.c	dm thin metadata: remove unused dm_pool_get_data_block_size()	2015-02-09 13:06:49 -05:00
dm-thin-metadata.h	dm thin metadata: remove unused dm_pool_get_data_block_size()	2015-02-09 13:06:49 -05:00
dm-thin.c	dm thin: fix to consistently zero-fill reads to unprovisioned blocks	2015-02-27 09:59:12 -05:00
dm-uevent.c
dm-uevent.h
dm-verity.c	dm verity: add error handling modes for corrupted blocks	2015-04-15 12:10:22 -04:00
dm-zero.c	dm crypt, dm zero: update author name following legal name change	2014-07-10 16:44:14 -04:00
dm.c	dm: fix casting bug in dm_merge_bvec()	2015-05-29 13:41:16 -04:00
dm.h	dm: add 'use_blk_mq' module param and expose in per-device ro sysfs attr	2015-04-15 12:10:17 -04:00
faulty.c	md: rename ->stop to ->free	2015-02-04 08:35:52 +11:00
Kconfig	md updates for 4.1	2015-04-24 09:28:01 -07:00
linear.c	md: rename ->stop to ->free	2015-02-04 08:35:52 +11:00
linear.h
Makefile	md updates for 4.1	2015-04-24 09:28:01 -07:00
md-cluster.c	md-cluster: re-add capabilities	2015-04-22 07:59:39 +10:00
md-cluster.h	md-cluster: re-add capabilities	2015-04-22 07:59:39 +10:00
md.c	md: convert to kstrto*()	2015-06-17 10:00:06 +10:00
md.h	md: remove 'go_faster' option from ->sync_request()	2015-04-22 08:00:40 +10:00
multipath.c	md: rename ->stop to ->free	2015-02-04 08:35:52 +11:00
multipath.h
raid0.c	md/raid0: fix restore to sector variable in raid0_make_request	2015-05-21 09:14:25 +10:00
raid0.h
raid1.c	md: remove 'go_faster' option from ->sync_request()	2015-04-22 08:00:40 +10:00
raid1.h	md: make ->congested robust against personality changes.	2015-02-04 08:35:52 +11:00
raid5.c	md/raid5: split wait_for_stripe and introduce wait_for_quiescent	2015-06-17 10:00:21 +10:00
raid5.h	md/raid5: split wait_for_stripe and introduce wait_for_quiescent	2015-06-17 10:00:21 +10:00
raid10.c	md/raid10: make sync_request_write() call bio_copy_data()	2015-06-17 09:59:57 +10:00
raid10.h	md: make ->congested robust against personality changes.	2015-02-04 08:35:52 +11:00