From 0f665ceb71a20520bdce76fb63ad68c21841aa62 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 24 Apr 2019 09:39:27 -0400 Subject: [PATCH] xprtrdma: De-duplicate "allocate new, free old regbuf" Clean up by providing an API to do this common task. At this point, the difference between rpcrdma_get_sendbuf and rpcrdma_get_recvbuf has become tiny. These can be collapsed into a single helper. Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker --- net/sunrpc/xprtrdma/transport.c | 59 +++++++-------------------------- net/sunrpc/xprtrdma/verbs.c | 25 ++++++++++++++ net/sunrpc/xprtrdma/xprt_rdma.h | 2 ++ 3 files changed, 39 insertions(+), 47 deletions(-) diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c index a5da43f3b035..8cf4fa36ed66 100644 --- a/net/sunrpc/xprtrdma/transport.c +++ b/net/sunrpc/xprtrdma/transport.c @@ -585,52 +585,15 @@ xprt_rdma_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *rqst) rpc_wake_up_next(&xprt->backlog); } -static bool -rpcrdma_get_sendbuf(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req, - size_t size, gfp_t flags) +static bool rpcrdma_check_regbuf(struct rpcrdma_xprt *r_xprt, + struct rpcrdma_regbuf *rb, size_t size, + gfp_t flags) { - struct rpcrdma_regbuf *rb; - - if (likely(rdmab_length(req->rl_sendbuf) >= size)) - return true; - - rb = rpcrdma_alloc_regbuf(size, DMA_TO_DEVICE, flags); - if (!rb) - return false; - - rpcrdma_free_regbuf(req->rl_sendbuf); - r_xprt->rx_stats.hardway_register_count += size; - req->rl_sendbuf = rb; - return true; -} - -/* The rq_rcv_buf is used only if a Reply chunk is necessary. - * The decision to use a Reply chunk is made later in - * rpcrdma_marshal_req. This buffer is registered at that time. - * - * Otherwise, the associated RPC Reply arrives in a separate - * Receive buffer, arbitrarily chosen by the HCA. The buffer - * allocated here for the RPC Reply is not utilized in that - * case. See rpcrdma_inline_fixup. - * - * A regbuf is used here to remember the buffer size. - */ -static bool -rpcrdma_get_recvbuf(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req, - size_t size, gfp_t flags) -{ - struct rpcrdma_regbuf *rb; - - if (likely(rdmab_length(req->rl_recvbuf) >= size)) - return true; - - rb = rpcrdma_alloc_regbuf(size, DMA_NONE, flags); - if (!rb) - return false; - - rpcrdma_free_regbuf(req->rl_recvbuf); - r_xprt->rx_stats.hardway_register_count += size; - req->rl_recvbuf = rb; + if (unlikely(rdmab_length(rb) < size)) { + if (!rpcrdma_regbuf_realloc(rb, size, flags)) + return false; + r_xprt->rx_stats.hardway_register_count += size; + } return true; } @@ -655,9 +618,11 @@ xprt_rdma_allocate(struct rpc_task *task) if (RPC_IS_SWAPPER(task)) flags = __GFP_MEMALLOC | GFP_NOWAIT | __GFP_NOWARN; - if (!rpcrdma_get_sendbuf(r_xprt, req, rqst->rq_callsize, flags)) + if (!rpcrdma_check_regbuf(r_xprt, req->rl_sendbuf, rqst->rq_callsize, + flags)) goto out_fail; - if (!rpcrdma_get_recvbuf(r_xprt, req, rqst->rq_rcvsize, flags)) + if (!rpcrdma_check_regbuf(r_xprt, req->rl_recvbuf, rqst->rq_rcvsize, + flags)) goto out_fail; rqst->rq_buffer = rdmab_data(req->rl_sendbuf); diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index 77e0f21c9017..734dfe5d18bd 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c @@ -1399,6 +1399,31 @@ rpcrdma_alloc_regbuf(size_t size, enum dma_data_direction direction, return rb; } +/** + * rpcrdma_regbuf_realloc - re-allocate a SEND/RECV buffer + * @rb: regbuf to reallocate + * @size: size of buffer to be allocated, in bytes + * @flags: GFP flags + * + * Returns true if reallocation was successful. If false is + * returned, @rb is left untouched. + */ +bool rpcrdma_regbuf_realloc(struct rpcrdma_regbuf *rb, size_t size, gfp_t flags) +{ + void *buf; + + buf = kmalloc(size, flags); + if (!buf) + return false; + + rpcrdma_dma_unmap_regbuf(rb); + kfree(rb->rg_data); + + rb->rg_data = buf; + rb->rg_iov.length = size; + return true; +} + /** * __rpcrdma_map_regbuf - DMA-map a regbuf * @ia: controlling rpcrdma_ia diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h index 03d5ce443bf0..751d4761d682 100644 --- a/net/sunrpc/xprtrdma/xprt_rdma.h +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -552,6 +552,8 @@ void rpcrdma_recv_buffer_put(struct rpcrdma_rep *); struct rpcrdma_regbuf *rpcrdma_alloc_regbuf(size_t, enum dma_data_direction, gfp_t); +bool rpcrdma_regbuf_realloc(struct rpcrdma_regbuf *rb, size_t size, + gfp_t flags); bool __rpcrdma_dma_map_regbuf(struct rpcrdma_ia *, struct rpcrdma_regbuf *); void rpcrdma_free_regbuf(struct rpcrdma_regbuf *);