linux/drivers/infiniband
Håkon Bugge 3aeffc46af IB/cma: Introduce rdma_set_min_rnr_timer()
Introduce the ability for kernel ULPs to adjust the minimum RNR Retry
timer. The INIT -> RTR transition executed by RDMA CM will be used for
this adjustment. This avoids an additional ib_modify_qp() call.

rdma_set_min_rnr_timer() must be called before the call to rdma_connect()
on the active side and before the call to rdma_accept() on the passive
side.

The default value of RNR Retry timer is zero, which translates to 655
ms. When the receiver is not ready to accept a send messages, it encodes
the RNR Retry timer value in the NAK. The requestor will then wait at
least the specified time value before retrying the send.

The 5-bit value to be supplied to the rdma_set_min_rnr_timer() is
documented in IBTA Table 45: "Encoding for RNR NAK Timer Field".

Link: https://lore.kernel.org/r/1617216194-12890-2-git-send-email-haakon.bugge@oracle.com
Signed-off-by: Håkon Bugge <haakon.bugge@oracle.com>
Acked-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2021-04-12 19:51:48 -03:00
..
core IB/cma: Introduce rdma_set_min_rnr_timer() 2021-04-12 19:51:48 -03:00
hw RDMA/i40iw: Use DEFINE_SPINLOCK() for spinlock 2021-04-12 15:37:38 -03:00
sw RDMA/rxe: Fix missing acks from responder 2021-04-08 15:59:28 -03:00
ulp IB/{ipoib,hfi1}: Add a timeout handler for rdma_netdev 2021-04-07 20:19:00 -03:00
Kconfig RDMA/umem: Support importing dma-buf as user memory region 2021-01-20 16:07:52 -04:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00