Extra resources for handling backchannel requests have to be pre-allocated when a transport instance is created. Set up additional fields in svcxprt_rdma to track these resources.
The max_requests fields are elements of the RPC-over-RDMA protocol, so they should be u32. To ensure that unsigned arithmetic is used everywhere, some other fields in the svcxprt_rdma struct are updated. Signed-off-by: Chuck Lever <[email protected]> --- include/linux/sunrpc/svc_rdma.h | 13 ++++++++++--- net/sunrpc/xprtrdma/svc_rdma.c | 6 ++++-- net/sunrpc/xprtrdma/svc_rdma_transport.c | 24 ++++++++++++++---------- 3 files changed, 28 insertions(+), 15 deletions(-) diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h index aeffa30..9a2c418 100644 --- a/include/linux/sunrpc/svc_rdma.h +++ b/include/linux/sunrpc/svc_rdma.h @@ -51,6 +51,7 @@ /* RPC/RDMA parameters and stats */ extern unsigned int svcrdma_ord; extern unsigned int svcrdma_max_requests; +extern unsigned int svcrdma_max_bc_requests; extern unsigned int svcrdma_max_req_size; extern atomic_t rdma_stat_recv; @@ -134,10 +135,11 @@ struct svcxprt_rdma { int sc_max_sge; int sc_max_sge_rd; /* max sge for read target */ - int sc_sq_depth; /* Depth of SQ */ atomic_t sc_sq_count; /* Number of SQ WR on queue */ - - int sc_max_requests; /* Depth of RQ */ + unsigned int sc_sq_depth; /* Depth of SQ */ + unsigned int sc_rq_depth; /* Depth of RQ */ + u32 sc_max_requests; /* Forward credits */ + u32 sc_max_bc_requests;/* Backward credits */ int sc_max_req_size; /* Size of each RQ WR buf */ struct ib_pd *sc_pd; @@ -186,6 +188,11 @@ struct svcxprt_rdma { #define RPCRDMA_MAX_REQUESTS 32 #define RPCRDMA_MAX_REQ_SIZE 4096 +/* Typical ULP usage of BC requests is NFSv4.1 backchannel. Our + * current NFSv4.1 implementation supports one backchannel slot. + */ +#define RPCRDMA_MAX_BC_REQUESTS 2 + #define RPCSVC_MAXPAYLOAD_RDMA RPCSVC_MAXPAYLOAD /* svc_rdma_marshal.c */ diff --git a/net/sunrpc/xprtrdma/svc_rdma.c b/net/sunrpc/xprtrdma/svc_rdma.c index e894e06..c846ca9 100644 --- a/net/sunrpc/xprtrdma/svc_rdma.c +++ b/net/sunrpc/xprtrdma/svc_rdma.c @@ -55,6 +55,7 @@ unsigned int svcrdma_ord = RPCRDMA_ORD; static unsigned int min_ord = 1; static unsigned int max_ord = 4096; unsigned int svcrdma_max_requests = RPCRDMA_MAX_REQUESTS; +unsigned int svcrdma_max_bc_requests = RPCRDMA_MAX_BC_REQUESTS; static unsigned int min_max_requests = 4; static unsigned int max_max_requests = 16384; unsigned int svcrdma_max_req_size = RPCRDMA_MAX_REQ_SIZE; @@ -245,9 +246,10 @@ int svc_rdma_init(void) { dprintk("SVCRDMA Module Init, register RPC RDMA transport\n"); dprintk("\tsvcrdma_ord : %d\n", svcrdma_ord); - dprintk("\tmax_requests : %d\n", svcrdma_max_requests); - dprintk("\tsq_depth : %d\n", + dprintk("\tmax_requests : %u\n", svcrdma_max_requests); + dprintk("\tsq_depth : %u\n", svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT); + dprintk("\tmax_bc_requests : %u\n", svcrdma_max_bc_requests); dprintk("\tmax_inline : %d\n", svcrdma_max_req_size); svc_rdma_wq = alloc_workqueue("svc_rdma", 0, 0); diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index 694ade4..35326a3 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -169,12 +169,12 @@ static struct svc_rdma_op_ctxt *alloc_ctxt(struct svcxprt_rdma *xprt, static bool svc_rdma_prealloc_ctxts(struct svcxprt_rdma *xprt) { - int i; + unsigned int i; /* Each RPC/RDMA credit can consume a number of send * and receive WQEs. One ctxt is allocated for each. */ - i = xprt->sc_sq_depth + xprt->sc_max_requests; + i = xprt->sc_sq_depth + xprt->sc_rq_depth; while (i--) { struct svc_rdma_op_ctxt *ctxt; @@ -285,7 +285,7 @@ static struct svc_rdma_req_map *alloc_req_map(gfp_t flags) static bool svc_rdma_prealloc_maps(struct svcxprt_rdma *xprt) { - int i; + unsigned int i; /* One for each receive buffer on this connection. */ i = xprt->sc_max_requests; @@ -1016,8 +1016,8 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) struct ib_device *dev; int uninitialized_var(dma_mr_acc); int need_dma_mr = 0; + unsigned int i; int ret = 0; - int i; listen_rdma = container_of(xprt, struct svcxprt_rdma, sc_xprt); clear_bit(XPT_CONN, &xprt->xpt_flags); @@ -1046,9 +1046,13 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) newxprt->sc_max_sge_rd = min_t(size_t, dev->max_sge_rd, RPCSVC_MAXPAGES); newxprt->sc_max_req_size = svcrdma_max_req_size; - newxprt->sc_max_requests = min((size_t)dev->max_qp_wr, - (size_t)svcrdma_max_requests); - newxprt->sc_sq_depth = RPCRDMA_SQ_DEPTH_MULT * newxprt->sc_max_requests; + newxprt->sc_max_requests = min_t(u32, dev->max_qp_wr, + svcrdma_max_requests); + newxprt->sc_max_bc_requests = min_t(u32, dev->max_qp_wr, + svcrdma_max_bc_requests); + newxprt->sc_rq_depth = newxprt->sc_max_requests + + newxprt->sc_max_bc_requests; + newxprt->sc_sq_depth = RPCRDMA_SQ_DEPTH_MULT * newxprt->sc_rq_depth; if (!svc_rdma_prealloc_ctxts(newxprt)) goto errout; @@ -1077,7 +1081,7 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) dprintk("svcrdma: error creating SQ CQ for connect request\n"); goto errout; } - cq_attr.cqe = newxprt->sc_max_requests; + cq_attr.cqe = newxprt->sc_rq_depth; newxprt->sc_rq_cq = ib_create_cq(dev, rq_comp_handler, cq_event_handler, @@ -1092,7 +1096,7 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) qp_attr.event_handler = qp_event_handler; qp_attr.qp_context = &newxprt->sc_xprt; qp_attr.cap.max_send_wr = newxprt->sc_sq_depth; - qp_attr.cap.max_recv_wr = newxprt->sc_max_requests; + qp_attr.cap.max_recv_wr = newxprt->sc_rq_depth; qp_attr.cap.max_send_sge = newxprt->sc_max_sge; qp_attr.cap.max_recv_sge = newxprt->sc_max_sge; qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR; @@ -1183,7 +1187,7 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) newxprt->sc_dma_lkey = dev->local_dma_lkey; /* Post receive buffers */ - for (i = 0; i < newxprt->sc_max_requests; i++) { + for (i = 0; i < newxprt->sc_rq_depth; i++) { ret = svc_rdma_post_recv(newxprt, GFP_KERNEL); if (ret) { dprintk("svcrdma: failure posting receive buffers\n"); -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
