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| author | Chuck Lever <chuck.lever@oracle.com> | 2018-05-04 22:34:48 +0300 |
|---|---|---|
| committer | Anna Schumaker <Anna.Schumaker@Netapp.com> | 2018-05-07 16:20:03 +0300 |
| commit | 914fcad9873cbd46e3a4c3c31551b98b15a49079 (patch) | |
| tree | d3a0779b4a7b0482728801b0ebec2c8ee110df22 /net/sunrpc/xprtrdma/frwr_ops.c | |
| parent | 107c4beb9bedd07d6e22f7010333dba3dc988292 (diff) | |
| download | linux-914fcad9873cbd46e3a4c3c31551b98b15a49079.tar.xz | |
xprtrdma: Fix max_send_wr computation
For FRWR, the computation of max_send_wr is split between
frwr_op_open and rpcrdma_ep_create, which makes it difficult to tell
that the max_send_wr result is currently incorrect if frwr_op_open
has to reduce the credit limit to accommodate a small max_qp_wr.
This is a problem now that extra WRs are needed for backchannel
operations and a drain CQE.
So, refactor the computation so that it is all done in ->ro_open,
and fix the FRWR version of this computation so that it
accommodates HCAs with small max_qp_wr correctly.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Diffstat (limited to 'net/sunrpc/xprtrdma/frwr_ops.c')
| -rw-r--r-- | net/sunrpc/xprtrdma/frwr_ops.c | 30 |
1 files changed, 26 insertions, 4 deletions
diff --git a/net/sunrpc/xprtrdma/frwr_ops.c b/net/sunrpc/xprtrdma/frwr_ops.c index c5743a0960be..0f2e108d387e 100644 --- a/net/sunrpc/xprtrdma/frwr_ops.c +++ b/net/sunrpc/xprtrdma/frwr_ops.c @@ -205,12 +205,22 @@ out_release: frwr_op_release_mr(mr); } +/* On success, sets: + * ep->rep_attr.cap.max_send_wr + * ep->rep_attr.cap.max_recv_wr + * cdata->max_requests + * ia->ri_max_segs + * + * And these FRWR-related fields: + * ia->ri_max_frwr_depth + * ia->ri_mrtype + */ static int frwr_op_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep, struct rpcrdma_create_data_internal *cdata) { struct ib_device_attr *attrs = &ia->ri_device->attrs; - int depth, delta; + int max_qp_wr, depth, delta; ia->ri_mrtype = IB_MR_TYPE_MEM_REG; if (attrs->device_cap_flags & IB_DEVICE_SG_GAPS_REG) @@ -244,14 +254,26 @@ frwr_op_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep, } while (delta > 0); } - ep->rep_attr.cap.max_send_wr *= depth; - if (ep->rep_attr.cap.max_send_wr > attrs->max_qp_wr) { - cdata->max_requests = attrs->max_qp_wr / depth; + max_qp_wr = ia->ri_device->attrs.max_qp_wr; + max_qp_wr -= RPCRDMA_BACKWARD_WRS; + max_qp_wr -= 1; + if (max_qp_wr < RPCRDMA_MIN_SLOT_TABLE) + return -ENOMEM; + if (cdata->max_requests > max_qp_wr) + cdata->max_requests = max_qp_wr; + ep->rep_attr.cap.max_send_wr = cdata->max_requests * depth; + if (ep->rep_attr.cap.max_send_wr > max_qp_wr) { + cdata->max_requests = max_qp_wr / depth; if (!cdata->max_requests) return -EINVAL; ep->rep_attr.cap.max_send_wr = cdata->max_requests * depth; } + ep->rep_attr.cap.max_send_wr += RPCRDMA_BACKWARD_WRS; + ep->rep_attr.cap.max_send_wr += 1; /* for ib_drain_sq */ + ep->rep_attr.cap.max_recv_wr = cdata->max_requests; + ep->rep_attr.cap.max_recv_wr += RPCRDMA_BACKWARD_WRS; + ep->rep_attr.cap.max_recv_wr += 1; /* for ib_drain_rq */ ia->ri_max_segs = max_t(unsigned int, 1, RPCRDMA_MAX_DATA_SEGS / ia->ri_max_frwr_depth); |