linux-stable/include
Markus Stockhausen 584acdd49c md/raid5: activate raid6 rmw feature
Glue it altogehter. The raid6 rmw path should work the same as the
already existing raid5 logic. So emulate the prexor handling/flags
and split functions as needed.

1) Enable xor_syndrome() in the async layer.

2) Split ops_run_prexor() into RAID4/5 and RAID6 logic. Xor the syndrome
at the start of a rmw run as we did it before for the single parity.

3) Take care of rmw run in ops_run_reconstruct6(). Again process only
the changed pages to get syndrome back into sync.

4) Enhance set_syndrome_sources() to fill NULL pages if we are in a rmw
run. The lower layers will calculate start & end pages from that and
call the xor_syndrome() correspondingly.

5) Adapt the several places where we ignored Q handling up to now.

Performance numbers for a single E5630 system with a mix of 10 7200k
desktop/server disks. 300 seconds random write with 8 threads onto a
3,2TB (10*400GB) RAID6 64K chunk without spare (group_thread_cnt=4)

bsize   rmw_level=1   rmw_level=0   rmw_level=1   rmw_level=0
        skip_copy=1   skip_copy=1   skip_copy=0   skip_copy=0
   4K      115 KB/s      141 KB/s      165 KB/s      140 KB/s
   8K      225 KB/s      275 KB/s      324 KB/s      274 KB/s
  16K      434 KB/s      536 KB/s      640 KB/s      534 KB/s
  32K      751 KB/s    1,051 KB/s    1,234 KB/s    1,045 KB/s
  64K    1,339 KB/s    1,958 KB/s    2,282 KB/s    1,962 KB/s
 128K    2,673 KB/s    3,862 KB/s    4,113 KB/s    3,898 KB/s
 256K    7,685 KB/s    7,539 KB/s    7,557 KB/s    7,638 KB/s
 512K   19,556 KB/s   19,558 KB/s   19,652 KB/s   19,688 Kb/s

Signed-off-by: Markus Stockhausen <stockhausen@collogia.de>
Signed-off-by: NeilBrown <neilb@suse.de>
2015-04-22 08:00:42 +10:00
..
acpi Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux 2015-02-19 11:28:36 -08:00
asm-generic OK, this has the big virtio 1.0 implementation, as specified by OASIS. 2015-02-18 09:24:01 -08:00
clocksource
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2015-02-14 09:47:01 -08:00
drm drm/ttm: device address space != CPU address space 2015-03-05 09:04:39 +10:00
dt-bindings ARM: dts: am43xx: fix SLEWCTRL_FAST pinctrl binding 2015-03-06 09:21:03 -08:00
keys
kvm arm/arm64: KVM: Keep elrsr/aisr in sync with software model 2015-03-14 13:42:07 +01:00
linux md/raid5: activate raid6 rmw feature 2015-04-22 08:00:42 +10:00
math-emu
media
memory
misc
net ipv6: protect skb->sk accesses from recursive dereference inside the stack 2015-04-06 16:12:49 -04:00
pcmcia
ras
rdma
rxrpc
scsi Merge branch 'for-3.20/core' of git://git.kernel.dk/linux-block 2015-02-12 14:13:23 -08:00
soc pm: at91: Workaround DDRSDRC self-refresh bug with LPDDR1 memories. 2015-03-03 19:43:59 +01:00
sound
target target: do not reject FUA CDBs when write cache is enabled but emulate_write_cache is 0 2015-03-19 23:26:46 -07:00
trace regmap: introduce regmap_name to fix syscon regmap trace events 2015-03-19 20:04:55 +00:00
uapi Merge branch 'cluster' into for-next 2015-04-22 08:00:20 +10:00
video OMAPDSS: fix regression with display sysfs files 2015-02-26 10:23:15 +02:00
xen xen: Remove trailing semicolon from xenbus_register_frontend() definition 2015-03-02 10:38:59 +00:00
Kbuild