From a062a2a3efc5fece106d96d4a5165f3f23b5cbda Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 20 Oct 2017 10:48:03 -0400 Subject: [PATCH] xprtrdma: "Unoptimize" rpcrdma_prepare_hdr_sge() 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 Signed-off-by: Anna Schumaker --- net/sunrpc/xprtrdma/rpc_rdma.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c index e3ece9843f9d..7fd102960a81 100644 --- a/net/sunrpc/xprtrdma/rpc_rdma.c +++ b/net/sunrpc/xprtrdma/rpc_rdma.c @@ -533,7 +533,7 @@ rpcrdma_unmap_sges(struct rpcrdma_ia *ia, struct rpcrdma_req *req) 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 @@ rpcrdma_prepare_hdr_sge(struct rpcrdma_ia *ia, struct rpcrdma_req *req, 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); -- 2.30.2