diff options
| author | Chuck Lever <chuck.lever@oracle.com> | 2018-05-07 15:28:25 -0400 |
|---|---|---|
| committer | J. Bruce Fields <bfields@redhat.com> | 2018-05-11 15:48:57 -0400 |
| commit | 99722fe4d5a634707ced8d8f42b883b87a86b3c5 (patch) | |
| tree | bc89587516be20f4c18330e63c28f087d8749896 /net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | |
| parent | 3abb03facee06ea052be6e3a435f6dbb4e54fc04 (diff) | |
svcrdma: Persistently allocate and DMA-map Send buffers
While sending each RPC Reply, svc_rdma_sendto allocates and DMA-
maps a separate buffer where the RPC/RDMA transport header is
constructed. The buffer is unmapped and released in the Send
completion handler. This is significant per-RPC overhead,
especially for small RPCs.
Instead, allocate and DMA-map a buffer, and cache it in each
svc_rdma_send_ctxt. This buffer and its mapping can be re-used
for each RPC, saving the cost of memory allocation and DMA
mapping.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'net/sunrpc/xprtrdma/svc_rdma_recvfrom.c')
| -rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 25 |
1 files changed, 6 insertions, 19 deletions
diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c index 68648e6c5be2..09ce09b3ac6e 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c @@ -602,17 +602,15 @@ static void svc_rdma_send_error(struct svcxprt_rdma *xprt, __be32 *rdma_argp, int status) { struct svc_rdma_send_ctxt *ctxt; - __be32 *p, *err_msgp; unsigned int length; - struct page *page; + __be32 *p; int ret; - page = alloc_page(GFP_KERNEL); - if (!page) + ctxt = svc_rdma_send_ctxt_get(xprt); + if (!ctxt) return; - err_msgp = page_address(page); - p = err_msgp; + p = ctxt->sc_xprt_buf; *p++ = *rdma_argp; *p++ = *(rdma_argp + 1); *p++ = xprt->sc_fc_credits; @@ -628,19 +626,8 @@ static void svc_rdma_send_error(struct svcxprt_rdma *xprt, *p++ = err_chunk; trace_svcrdma_err_chunk(*rdma_argp); } - length = (unsigned long)p - (unsigned long)err_msgp; - - /* Map transport header; no RPC message payload */ - ctxt = svc_rdma_send_ctxt_get(xprt); - if (!ctxt) - return; - - ret = svc_rdma_map_reply_hdr(xprt, ctxt, err_msgp, length); - if (ret) { - dprintk("svcrdma: Error %d mapping send for protocol error\n", - ret); - return; - } + length = (unsigned long)p - (unsigned long)ctxt->sc_xprt_buf; + svc_rdma_sync_reply_hdr(xprt, ctxt, length); ctxt->sc_send_wr.opcode = IB_WR_SEND; ret = svc_rdma_send(xprt, &ctxt->sc_send_wr); |