This change improves Receive efficiency by posting Receives only
on the same CPU that handles Receive completion. Improved latency
and throughput has been noted with this change.
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
include/linux/sunrpc/svc_rdma.h | 2 --
net/sunrpc/xprtrdma/svc_rdma_backchannel.c | 5 -----
net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 9 +--------
net/sunrpc/xprtrdma/svc_rdma_sendto.c | 6 ------
net/sunrpc/xprtrdma/svc_rdma_transport.c | 25 +++++++------------------
5 files changed, 8 insertions(+), 39 deletions(-)
diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h
index 995c6fe..4b731b0 100644
--- a/include/linux/sunrpc/svc_rdma.h
+++ b/include/linux/sunrpc/svc_rdma.h
@@ -185,8 +185,6 @@ extern int svc_rdma_post_send_wr(struct svcxprt_rdma *rdma,
extern void svc_rdma_wc_read(struct ib_cq *, struct ib_wc *);
extern void svc_rdma_wc_inv(struct ib_cq *, struct ib_wc *);
extern int svc_rdma_send(struct svcxprt_rdma *, struct ib_send_wr *);
-extern int svc_rdma_post_recv(struct svcxprt_rdma *, gfp_t);
-extern int svc_rdma_repost_recv(struct svcxprt_rdma *, gfp_t);
extern int svc_rdma_create_listen(struct svc_serv *, int, struct sockaddr *);
extern struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *);
extern void svc_rdma_put_context(struct svc_rdma_op_ctxt *, int);
diff --git a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
index af78935..a73632c 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
@@ -95,7 +95,6 @@ int svc_rdma_handle_bc_reply(struct rpc_xprt *xprt, __be32 *rdma_resp,
out_notfound:
dprintk("svcrdma: unrecognized bc reply: xprt=%p, xid=%08x\n",
xprt, be32_to_cpu(xid));
-
goto out_unlock;
}
@@ -129,10 +128,6 @@ static int svc_rdma_bc_sendto(struct svcxprt_rdma *rdma,
if (ret < 0)
goto out_err;
- ret = svc_rdma_repost_recv(rdma, GFP_NOIO);
- if (ret)
- goto out_err;
-
/* Bump page refcnt so Send completion doesn't release
* the rq_buffer before all retransmits are complete.
*/
diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
index ad4bd62..19e9c6b 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
@@ -400,10 +400,6 @@ static void svc_rdma_send_error(struct svcxprt_rdma *xprt,
struct page *page;
int ret;
- ret = svc_rdma_repost_recv(xprt, GFP_KERNEL);
- if (ret)
- return;
-
page = alloc_page(GFP_KERNEL);
if (!page)
return;
@@ -554,8 +550,6 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp)
ret = svc_rdma_handle_bc_reply(xprt->xpt_bc_xprt, p,
&rqstp->rq_arg);
svc_rdma_put_context(ctxt, 0);
- if (ret)
- goto repost;
return ret;
}
@@ -590,6 +584,5 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp)
out_drop:
svc_rdma_put_context(ctxt, 1);
-repost:
- return svc_rdma_repost_recv(rdma_xprt, GFP_KERNEL);
+ return 0;
}
diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
index 7c3a211..649441d 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
@@ -674,9 +674,6 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
svc_rdma_xdr_encode_reply_chunk(rdma_resp, rp_ch, ret);
}
- ret = svc_rdma_post_recv(rdma, GFP_KERNEL);
- if (ret)
- goto err1;
ret = svc_rdma_send_reply_msg(rdma, rdma_argp, rdma_resp, rqstp,
wr_lst, rp_ch);
if (ret < 0)
@@ -687,9 +684,6 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
if (ret != -E2BIG && ret != -EINVAL)
goto err1;
- ret = svc_rdma_post_recv(rdma, GFP_KERNEL);
- if (ret)
- goto err1;
ret = svc_rdma_send_error_msg(rdma, rdma_resp, rqstp);
if (ret < 0)
goto err0;
diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c
index 46ec069..9ad12a2 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_transport.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c
@@ -58,6 +58,7 @@
#define RPCDBG_FACILITY RPCDBG_SVCXPRT
+static int svc_rdma_post_recv(struct svcxprt_rdma *xprt);
static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *, int);
static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
struct net *net,
@@ -320,6 +321,8 @@ static void svc_rdma_wc_receive(struct ib_cq *cq, struct ib_wc *wc)
list_add_tail(&ctxt->list, &xprt->sc_rq_dto_q);
spin_unlock(&xprt->sc_rq_dto_lock);
+ svc_rdma_post_recv(xprt);
+
set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags);
if (test_bit(RDMAXPRT_CONN_PENDING, &xprt->sc_flags))
goto out;
@@ -404,7 +407,8 @@ static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv,
return cma_xprt;
}
-int svc_rdma_post_recv(struct svcxprt_rdma *xprt, gfp_t flags)
+static int
+svc_rdma_post_recv(struct svcxprt_rdma *xprt)
{
struct ib_recv_wr recv_wr, *bad_recv_wr;
struct svc_rdma_op_ctxt *ctxt;
@@ -423,7 +427,7 @@ int svc_rdma_post_recv(struct svcxprt_rdma *xprt, gfp_t flags)
pr_err("svcrdma: Too many sges (%d)\n", sge_no);
goto err_put_ctxt;
}
- page = alloc_page(flags);
+ page = alloc_page(GFP_KERNEL);
if (!page)
goto err_put_ctxt;
ctxt->pages[sge_no] = page;
@@ -459,21 +463,6 @@ int svc_rdma_post_recv(struct svcxprt_rdma *xprt, gfp_t flags)
return -ENOMEM;
}
-int svc_rdma_repost_recv(struct svcxprt_rdma *xprt, gfp_t flags)
-{
- int ret = 0;
-
- ret = svc_rdma_post_recv(xprt, flags);
- if (ret) {
- pr_err("svcrdma: could not post a receive buffer, err=%d.\n",
- ret);
- pr_err("svcrdma: closing transport %p.\n", xprt);
- set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
- ret = -ENOTCONN;
- }
- return ret;
-}
-
static void
svc_rdma_parse_connect_private(struct svcxprt_rdma *newxprt,
struct rdma_conn_param *param)
@@ -833,7 +822,7 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt)
/* Post receive buffers */
for (i = 0; i < newxprt->sc_max_requests; i++) {
- ret = svc_rdma_post_recv(newxprt, GFP_KERNEL);
+ ret = svc_rdma_post_recv(newxprt);
if (ret) {
dprintk("svcrdma: failure posting receive buffers\n");
goto errout;
--
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