diff mbox

[4/9] xprtrdma: "Unoptimize" rpcrdma_prepare_hdr_sge()

Message ID 20171020144803.14869.67223.stgit@manet.1015granger.net (mailing list archive)
State New, archived
Headers show

Commit Message

Chuck Lever Oct. 20, 2017, 2:48 p.m. UTC 
Commit 655fec6987be ("xprtrdma: Use gathered Send for large inline
messages") assumed that, since the zeroeth element of the Send SGE
array always pointed to req->rl_rdmabuf, it needed to be initialized
just once. This was a valid assumption because the Send SGE array
and rl_rdmabuf both live in the same rpcrdma_req.

In a subsequent patch, the Send SGE array will be separated from the
rpcrdma_req, so the zeroeth element of the SGE array needs to be
initialized every time.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 net/sunrpc/xprtrdma/rpc_rdma.c |   12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)


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diff mbox

Patch

diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index e3ece98..7fd1029 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -533,7 +533,7 @@  static bool rpcrdma_results_inline(struct rpcrdma_xprt *r_xprt,
 				  sge->addr, sge->length, DMA_TO_DEVICE);
 }
 
-/* Prepare the RPC-over-RDMA header SGE.
+/* Prepare an SGE for the RPC-over-RDMA transport header.
  */
 static bool
 rpcrdma_prepare_hdr_sge(struct rpcrdma_ia *ia, struct rpcrdma_req *req,
@@ -542,13 +542,11 @@  static bool rpcrdma_results_inline(struct rpcrdma_xprt *r_xprt,
 	struct rpcrdma_regbuf *rb = req->rl_rdmabuf;
 	struct ib_sge *sge = &req->rl_send_sge[0];
 
-	if (unlikely(!rpcrdma_regbuf_is_mapped(rb))) {
-		if (!__rpcrdma_dma_map_regbuf(ia, rb))
-			goto out_regbuf;
-		sge->addr = rdmab_addr(rb);
-		sge->lkey = rdmab_lkey(rb);
-	}
+	if (!rpcrdma_dma_map_regbuf(ia, rb))
+		goto out_regbuf;
+	sge->addr = rdmab_addr(rb);
 	sge->length = len;
+	sge->lkey = rdmab_lkey(rb);
 
 	ib_dma_sync_single_for_device(rdmab_device(rb), sge->addr,
 				      sge->length, DMA_TO_DEVICE);