Open MPI, Intel MPI and other applications don't respect the iWARP
requirement that the client (active) side of the connection send the
first RDMA message. This class of application connection setup is
called peer-to-peer. Typically once the connection is setup, _both_
sides want to send data.
This patch enables supporting peer-to-peer over the chelsio RNIC by
enforcing this iWARP requirement in the driver itself as part of RDMA
connection setup.
Connection setup is extended, when the peer2peer module option is 1,
such that the MPA initiator will send a 0B Read (the RTR) just after
connection setup. The MPA responder will suspend SQ processing until
the RTR message is received and reply-to.
In the longer term, this will be handled in a standardized way by
enhancing the MPA negotiation so peers can indicate whether they
want/need the RTR and what type of RTR (0B read, 0B write, or 0B send)
should be sent. This will be done by standardizing a few bits of the
private data in order to negotiate all this. However this patch
enables peer-to-peer applications now and allows most of the required
firmware and driver changes to be done and tested now.
Design:
- Add a module option, peer2peer, to enable this mode.
- New firmware support for peer-to-peer mode:
- a new bit in the rdma_init WR to tell it to do peer-2-peer
and what form of RTR message to send or expect.
- process _all_ preposted recvs before moving the connection
into rdma mode.
- passive side: defer completing the rdma_init WR until all
pre-posted recvs are processed. Suspend SQ processing until
the RTR is received.
- active side: expect and process the 0B read WR on offload TX
queue. Defer completing the rdma_init WR until all
pre-posted recvs are processed. Suspend SQ processing until
the 0B read WR is processed from the offload TX queue.
- If peer2peer is set, driver posts 0B read request on offload TX
queue just after posting the rdma_init WR to the offload TX queue.
- Add CQ poll logic to ignore unsolicitied read responses.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Open MPI and other stress testing exposed a few bad bugs in handling
aborts in the middle of a normal close. Fix these by:
- serializing abort reply and peer abort processing with disconnect
processing
- warning (and ignoring) if ep timer is stopped when it wasn't running
- cleaning up disconnect path to correctly deal with aborting and
dead endpoints
- in iwch_modify_qp(), taking a ref on the ep before releasing the qp
lock if iwch_ep_disconnect() will be called. The ref is dropped
after calling disconnect.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
__FUNCTION__ is gcc-specific, use __func__ instead.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Due to a HW issue, our current scheme to transition the connection from
streaming to rdma mode is broken on the passive side. The firmware
and driver now support a new transition scheme for the passive side:
- driver posts rdma_init_wr (now including the initial receive seqno)
- driver posts last streaming message via TX_DATA message (MPA start
response)
- uP atomically sends the last streaming message and transitions the
tcb to rdma mode.
- driver waits for wr_ack indicating the last streaming message was ACKed.
NOTE: This change also bumps the required firmware version to 4.3.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The HW now posts 2 ABORT_RPL and/or PEER_ABORT_REQ messages. We need
to handle them by silenty dropping the 1st but mark that we're ready
for the final message. This plugs some close races between the uP and
HW. Also update the minimum required firmware version.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Remove the Open Grid Computing copyright. It shouldn't be there.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Add an RDMA/iWARP driver for the Chelsio T3 1GbE and 10GbE adapters.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Steve Wise
Harvey Harrison