tree 609a1370a1a8d416c789905c17607bd8d31c6242
parent 05a1d7504f836ee67e27f2488cb5b8126b51dbd4
author Bart Van Assche <bvanassche@acm.org> 1283196456 +0000
committer Roland Dreier <rolandd@cisco.com> 1287983654 -0700

IB/srp: Reduce number of BUSY conditions

As proposed by the SRP (draft) standard, ib_srp reserves one ring
element for SRP_TSK_MGMT requests. This patch makes sure that the SCSI
mid-layer never tries to queue more than (SRP request limit) - 1 SCSI
commands to ib_srp. This improves performance for targets whose request
limit is less than or equal to SRP_NORMAL_REQ_SQ_SIZE by reducing the
number of BUSY responses reported by ib_srp to the SCSI mid-layer.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: David Dillow <dillowda@ornl.gov>
Signed-off-by: Roland Dreier <rolandd@cisco.com>