linux/drivers/md
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
..
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 change version from string to integer set 2013-03-20 17:21:27 +00:00
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: replace simple_strtoul 2012-07-27 15:07:59 +01:00
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: stop using WQ_NON_REENTRANT 2013-08-23 09:02:13 -04:00
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: use memweight() 2012-07-30 17:25:16 -07:00
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: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-raid1.c dm mirror: do not degrade the mirror on discard error 2015-02-13 19:50:46 -05:00
dm-raid.c - Most significant change this cycle is request-based DM now supports 2015-02-12 16:36:31 -08:00
dm-region-hash.c block: Abstract out bvec iterator 2013-11-23 22:33:47 -08:00
dm-round-robin.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-service-time.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
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: add statistics support 2013-09-05 20:46:06 -04:00
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