s390/dasd: fix performance drop
authorStefan Haberland <sth@linux.vnet.ibm.com>
Fri, 12 Feb 2016 13:50:52 +0000 (14:50 +0100)
committerMartin Schwidefsky <schwidefsky@de.ibm.com>
Wed, 17 Feb 2016 08:24:07 +0000 (09:24 +0100)
commit12d319b920fa673a4d5e7c1785c5dc82dcd15257
treed118d395bbbe32bb3295ce739fcf63b63e45943d
parent52499d93d6dec3872de3b982219af6d4c182a452
s390/dasd: fix performance drop

Commit ca369d51b ("sd: Fix device-imposed transfer length limits")
introduced a new queue limit max_dev_sectors which limits the maximum
sectors for requests. The default value leads to small dasd requests
and therefor to a performance drop.
Set the max_dev_sectors value to the same value as the max_hw_sectors
to use the maximum available request size for DASD devices.

Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # 4.4+
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
drivers/s390/block/dasd.c