summaryrefslogtreecommitdiff
path: root/net/sunrpc
diff options
context:
space:
mode:
authorChuck Lever <chuck.lever@oracle.com>2016-03-04 19:28:36 +0300
committerAnna Schumaker <Anna.Schumaker@Netapp.com>2016-03-14 21:56:04 +0300
commit552bf225281f96e7a02e1a1b874966fdb6b997e0 (patch)
tree6dc7f21bc30ff3e0e7ac1c9c2d465069ed9c612c /net/sunrpc
parent23826c7aeac7e333bfee6f10a3407a23c58b6147 (diff)
downloadlinux-552bf225281f96e7a02e1a1b874966fdb6b997e0.tar.xz
xprtrdma: Use new CQ API for RPC-over-RDMA client receive CQs
Calling ib_poll_cq() to sort through WCs during a completion is a common pattern amongst RDMA consumers. Since commit 14d3a3b2498e ("IB: add a proper completion queue abstraction"), WC sorting can be handled by the IB core. By converting to this new API, xprtrdma is made a better neighbor to other RDMA consumers, as it allows the core to schedule the delivery of completions more fairly amongst all active consumers. Because each ib_cqe carries a pointer to a completion method, the core can now post its own operations on a consumer's QP, and handle the completions itself, without changes to the consumer. xprtrdma's reply processing is already handled in a work queue, but there is some initial order-dependent processing that is done in the soft IRQ context before a work item is scheduled. IB_POLL_SOFTIRQ is a direct replacement for the current xprtrdma receive code path. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Devesh Sharma <devesh.sharma@broadcom.com> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Diffstat (limited to 'net/sunrpc')
-rw-r--r--net/sunrpc/xprtrdma/verbs.c78
-rw-r--r--net/sunrpc/xprtrdma/xprt_rdma.h1
2 files changed, 21 insertions, 58 deletions
diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index fc1ef5f144b8..05779f48745b 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -212,11 +212,18 @@ rpcrdma_update_granted_credits(struct rpcrdma_rep *rep)
atomic_set(&buffer->rb_credits, credits);
}
+/**
+ * rpcrdma_receive_wc - Invoked by RDMA provider for each polled Receive WC
+ * @cq: completion queue (ignored)
+ * @wc: completed WR
+ *
+ */
static void
-rpcrdma_recvcq_process_wc(struct ib_wc *wc)
+rpcrdma_receive_wc(struct ib_cq *cq, struct ib_wc *wc)
{
- struct rpcrdma_rep *rep =
- (struct rpcrdma_rep *)(unsigned long)wc->wr_id;
+ struct ib_cqe *cqe = wc->wr_cqe;
+ struct rpcrdma_rep *rep = container_of(cqe, struct rpcrdma_rep,
+ rr_cqe);
/* WARNING: Only wr_id and status are reliable at this point */
if (wc->status != IB_WC_SUCCESS)
@@ -242,55 +249,20 @@ out_schedule:
out_fail:
if (wc->status != IB_WC_WR_FLUSH_ERR)
- pr_err("RPC: %s: rep %p: %s\n",
- __func__, rep, ib_wc_status_msg(wc->status));
+ pr_err("rpcrdma: Recv: %s (%u/0x%x)\n",
+ ib_wc_status_msg(wc->status),
+ wc->status, wc->vendor_err);
rep->rr_len = RPCRDMA_BAD_LEN;
goto out_schedule;
}
-/* The wc array is on stack: automatic memory is always CPU-local.
- *
- * struct ib_wc is 64 bytes, making the poll array potentially
- * large. But this is at the bottom of the call chain. Further
- * substantial work is done in another thread.
- */
-static void
-rpcrdma_recvcq_poll(struct ib_cq *cq)
-{
- struct ib_wc *pos, wcs[4];
- int count, rc;
-
- do {
- pos = wcs;
-
- rc = ib_poll_cq(cq, ARRAY_SIZE(wcs), pos);
- if (rc < 0)
- break;
-
- count = rc;
- while (count-- > 0)
- rpcrdma_recvcq_process_wc(pos++);
- } while (rc == ARRAY_SIZE(wcs));
-}
-
-/* Handle provider receive completion upcalls.
- */
-static void
-rpcrdma_recvcq_upcall(struct ib_cq *cq, void *cq_context)
-{
- do {
- rpcrdma_recvcq_poll(cq);
- } while (ib_req_notify_cq(cq, IB_CQ_NEXT_COMP |
- IB_CQ_REPORT_MISSED_EVENTS) > 0);
-}
-
static void
rpcrdma_flush_cqs(struct rpcrdma_ep *ep)
{
struct ib_wc wc;
while (ib_poll_cq(ep->rep_attr.recv_cq, 1, &wc) > 0)
- rpcrdma_recvcq_process_wc(&wc);
+ rpcrdma_receive_wc(NULL, &wc);
while (ib_poll_cq(ep->rep_attr.send_cq, 1, &wc) > 0)
rpcrdma_sendcq_process_wc(&wc);
}
@@ -655,9 +627,9 @@ rpcrdma_ep_create(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia,
goto out2;
}
- cq_attr.cqe = ep->rep_attr.cap.max_recv_wr + 1;
- recvcq = ib_create_cq(ia->ri_device, rpcrdma_recvcq_upcall,
- rpcrdma_cq_async_error_upcall, NULL, &cq_attr);
+ recvcq = ib_alloc_cq(ia->ri_device, NULL,
+ ep->rep_attr.cap.max_recv_wr + 1,
+ 0, IB_POLL_SOFTIRQ);
if (IS_ERR(recvcq)) {
rc = PTR_ERR(recvcq);
dprintk("RPC: %s: failed to create recv CQ: %i\n",
@@ -665,14 +637,6 @@ rpcrdma_ep_create(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia,
goto out2;
}
- rc = ib_req_notify_cq(recvcq, IB_CQ_NEXT_COMP);
- if (rc) {
- dprintk("RPC: %s: ib_req_notify_cq failed: %i\n",
- __func__, rc);
- ib_destroy_cq(recvcq);
- goto out2;
- }
-
ep->rep_attr.send_cq = sendcq;
ep->rep_attr.recv_cq = recvcq;
@@ -735,10 +699,7 @@ rpcrdma_ep_destroy(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
ia->ri_id->qp = NULL;
}
- rc = ib_destroy_cq(ep->rep_attr.recv_cq);
- if (rc)
- dprintk("RPC: %s: ib_destroy_cq returned %i\n",
- __func__, rc);
+ ib_free_cq(ep->rep_attr.recv_cq);
rc = ib_destroy_cq(ep->rep_attr.send_cq);
if (rc)
@@ -947,6 +908,7 @@ rpcrdma_create_rep(struct rpcrdma_xprt *r_xprt)
}
rep->rr_device = ia->ri_device;
+ rep->rr_cqe.done = rpcrdma_receive_wc;
rep->rr_rxprt = r_xprt;
INIT_WORK(&rep->rr_work, rpcrdma_receive_worker);
return rep;
@@ -1322,7 +1284,7 @@ rpcrdma_ep_post_recv(struct rpcrdma_ia *ia,
int rc;
recv_wr.next = NULL;
- recv_wr.wr_id = (u64) (unsigned long) rep;
+ recv_wr.wr_cqe = &rep->rr_cqe;
recv_wr.sg_list = &rep->rr_rdmabuf->rg_iov;
recv_wr.num_sge = 1;
diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h
index 7bf6f43fa4b9..d60feb9aa631 100644
--- a/net/sunrpc/xprtrdma/xprt_rdma.h
+++ b/net/sunrpc/xprtrdma/xprt_rdma.h
@@ -171,6 +171,7 @@ rdmab_to_msg(struct rpcrdma_regbuf *rb)
struct rpcrdma_buffer;
struct rpcrdma_rep {
+ struct ib_cqe rr_cqe;
unsigned int rr_len;
struct ib_device *rr_device;
struct rpcrdma_xprt *rr_rxprt;