T3 hardware doorbell FIFO overflows can cause application stalls due
to lost doorbell ring events. This has been seen when running large
NP IMB alltoall MPI jobs. The T3 hardware supports an xon/xoff-type
flow control mechanism to help avoid overflowing the HW doorbell FIFO.
This patch uses these interrupts to disable RDMA QP doorbell rings
when we near an overflow condition, and then turn them back on (and
ring all the active QP doorbells) when when the doorbell FIFO empties
out. In addition if an doorbell ring is dropped by the hardware, the
code will now recover.
Design:
cxgb3:
- enable these DB interrupts
- in the interrupt handler, schedule work tasks to call the ULPs event
handlers with the new events.
- ring all the qset txqs when an overflow is detected.
iw_cxgb3:
- disable db ringing on all active qps when we get the DB_FULL event
- enable db ringing on all active qps and ring all active dbs when we get
the DB_EMPTY event
- On DB_DROP event:
- disable db rings in the event handler
- delay-schedule a work task which rings and enables the dbs on
all active qps.
- in post_send and post_recv logic, don't ring the db if it's disabled.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
T3 firmware only supports one WRs worth of page list for fast register
work requests. The driver currently allows 2 WRs worth, which
doesn't work for T3, so reduce the limit in the driver.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The poll and flush code needs to handle all send opcodes: SEND,
SEND_WITH_SE, SEND_WITH_INV, and SEND_WITH_SE_INV.
Ignore TERM indications if the connection already gone.
Ignore HW receive completions if the RQ is empty.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Handling the zero STag in receive work request requires some extra
logic in the driver:
- Only set the QP_PRIV bit for kernel mode QPs.
- Add a zero STag build function for recv wrs. The uP needs a PBL
allocated and passed down in the recv WR so it can construct a HW
PBL for the zero STag S/G entries. Note: we need to place a few
restrictions on zero STag usage because of this:
1) all SGEs in a recv WR must either be zero STag or not. No mixing.
2) an individual SGE length cannot exceed 128MB for a zero-stag SGE.
This should be OK since it's not really practical to allocate
such a large chunk of pinned contiguous DMA mapped memory.
- Add an optimized non-zero-STag recv wr format for kernel users.
This is needed to optimize both zero and non-zero STag cracking in
the recv path for kernel users.
- Remove the iwch_ prefix from the static build functions.
- Bump required FW version.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
- set IB_DEVICE_MEM_MGT_EXTENSIONS capability bit if fw supports it.
- set max_fast_reg_page_list_len device attribute.
- add iwch_alloc_fast_reg_mr function.
- add iwch_alloc_fastreg_pbl
- add iwch_free_fastreg_pbl
- adjust the WQ depth for kernel mode work queues to account for
fastreg possibly taking 2 WR slots.
- add fastreg_mr work request support.
- add local_inv work request support.
- add send_with_inv and send_with_se_inv work request support.
- removed useless duplicate enums/defines for TPT/MW/MR stuff.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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>
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>
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>
