Return-Path: Received: from mail-ig0-f177.google.com ([209.85.213.177]:37975 "EHLO mail-ig0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751754AbbCXUbg (ORCPT ); Tue, 24 Mar 2015 16:31:36 -0400 Subject: [PATCH v2 07/15] xprtrdma: Add a "max_payload" op for each memreg mode From: Chuck Lever To: linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org Date: Tue, 24 Mar 2015 16:31:33 -0400 Message-ID: <20150324203133.2311.92561.stgit@manet.1015granger.net> In-Reply-To: <20150324201849.2311.53599.stgit@manet.1015granger.net> References: <20150324201849.2311.53599.stgit@manet.1015granger.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: The max_payload computation is generalized to ensure that the payload maximum is the lesser of RPC_MAX_DATA_SEGS and the number of data segments that can be transmitted in an inline buffer. Signed-off-by: Chuck Lever Reviewed-by: Sagi Grimberg --- net/sunrpc/xprtrdma/fmr_ops.c | 13 ++++++++++ net/sunrpc/xprtrdma/frwr_ops.c | 13 ++++++++++ net/sunrpc/xprtrdma/physical_ops.c | 10 +++++++ net/sunrpc/xprtrdma/transport.c | 5 +++- net/sunrpc/xprtrdma/verbs.c | 49 +++++++++++------------------------- net/sunrpc/xprtrdma/xprt_rdma.h | 5 +++- 6 files changed, 59 insertions(+), 36 deletions(-) diff --git a/net/sunrpc/xprtrdma/fmr_ops.c b/net/sunrpc/xprtrdma/fmr_ops.c index ffb7d93..eec2660 100644 --- a/net/sunrpc/xprtrdma/fmr_ops.c +++ b/net/sunrpc/xprtrdma/fmr_ops.c @@ -17,6 +17,19 @@ # define RPCDBG_FACILITY RPCDBG_TRANS #endif +/* Maximum scatter/gather per FMR */ +#define RPCRDMA_MAX_FMR_SGES (64) + +/* FMR mode conveys up to 64 pages of payload per chunk segment. + */ +static size_t +fmr_op_maxpages(struct rpcrdma_xprt *r_xprt) +{ + return min_t(unsigned int, RPCRDMA_MAX_DATA_SEGS, + rpcrdma_max_segments(r_xprt) * RPCRDMA_MAX_FMR_SGES); +} + const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops = { + .ro_maxpages = fmr_op_maxpages, .ro_displayname = "fmr", }; diff --git a/net/sunrpc/xprtrdma/frwr_ops.c b/net/sunrpc/xprtrdma/frwr_ops.c index 79173f9..73a5ac8 100644 --- a/net/sunrpc/xprtrdma/frwr_ops.c +++ b/net/sunrpc/xprtrdma/frwr_ops.c @@ -17,6 +17,19 @@ # define RPCDBG_FACILITY RPCDBG_TRANS #endif +/* FRWR mode conveys a list of pages per chunk segment. The + * maximum length of that list is the FRWR page list depth. + */ +static size_t +frwr_op_maxpages(struct rpcrdma_xprt *r_xprt) +{ + struct rpcrdma_ia *ia = &r_xprt->rx_ia; + + return min_t(unsigned int, RPCRDMA_MAX_DATA_SEGS, + rpcrdma_max_segments(r_xprt) * ia->ri_max_frmr_depth); +} + const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops = { + .ro_maxpages = frwr_op_maxpages, .ro_displayname = "frwr", }; diff --git a/net/sunrpc/xprtrdma/physical_ops.c b/net/sunrpc/xprtrdma/physical_ops.c index b0922ac..28ade19 100644 --- a/net/sunrpc/xprtrdma/physical_ops.c +++ b/net/sunrpc/xprtrdma/physical_ops.c @@ -19,6 +19,16 @@ # define RPCDBG_FACILITY RPCDBG_TRANS #endif +/* PHYSICAL memory registration conveys one page per chunk segment. + */ +static size_t +physical_op_maxpages(struct rpcrdma_xprt *r_xprt) +{ + return min_t(unsigned int, RPCRDMA_MAX_DATA_SEGS, + rpcrdma_max_segments(r_xprt)); +} + const struct rpcrdma_memreg_ops rpcrdma_physical_memreg_ops = { + .ro_maxpages = physical_op_maxpages, .ro_displayname = "physical", }; diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c index 97f6562..da71a24 100644 --- a/net/sunrpc/xprtrdma/transport.c +++ b/net/sunrpc/xprtrdma/transport.c @@ -406,7 +406,10 @@ xprt_setup_rdma(struct xprt_create *args) xprt_rdma_connect_worker); xprt_rdma_format_addresses(xprt); - xprt->max_payload = rpcrdma_max_payload(new_xprt); + xprt->max_payload = new_xprt->rx_ia.ri_ops->ro_maxpages(new_xprt); + if (xprt->max_payload == 0) + goto out4; + xprt->max_payload <<= PAGE_SHIFT; dprintk("RPC: %s: transport data payload maximum: %zu bytes\n", __func__, xprt->max_payload); diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index c3319e1..da55cda 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c @@ -2212,43 +2212,24 @@ rpcrdma_ep_post_recv(struct rpcrdma_ia *ia, return rc; } -/* Physical mapping means one Read/Write list entry per-page. - * All list entries must fit within an inline buffer - * - * NB: The server must return a Write list for NFS READ, - * which has the same constraint. Factor in the inline - * rsize as well. +/* How many chunk list items fit within our inline buffers? */ -static size_t -rpcrdma_physical_max_payload(struct rpcrdma_xprt *r_xprt) +unsigned int +rpcrdma_max_segments(struct rpcrdma_xprt *r_xprt) { struct rpcrdma_create_data_internal *cdata = &r_xprt->rx_data; - unsigned int inline_size, pages; - - inline_size = min_t(unsigned int, - cdata->inline_wsize, cdata->inline_rsize); - inline_size -= RPCRDMA_HDRLEN_MIN; - pages = inline_size / sizeof(struct rpcrdma_segment); - return pages << PAGE_SHIFT; -} + int bytes, segments; -static size_t -rpcrdma_mr_max_payload(struct rpcrdma_xprt *r_xprt) -{ - return RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT; -} - -size_t -rpcrdma_max_payload(struct rpcrdma_xprt *r_xprt) -{ - size_t result; - - switch (r_xprt->rx_ia.ri_memreg_strategy) { - case RPCRDMA_ALLPHYSICAL: - result = rpcrdma_physical_max_payload(r_xprt); - break; - default: - result = rpcrdma_mr_max_payload(r_xprt); + bytes = min_t(unsigned int, cdata->inline_wsize, cdata->inline_rsize); + bytes -= RPCRDMA_HDRLEN_MIN; + if (bytes < sizeof(struct rpcrdma_segment) * 2) { + pr_warn("RPC: %s: inline threshold too small\n", + __func__); + return 0; } - return result; + + segments = 1 << (fls(bytes / sizeof(struct rpcrdma_segment)) - 1); + dprintk("RPC: %s: max chunk list size = %d segments\n", + __func__, segments); + return segments; } diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h index ef3cf4a..59e627e 100644 --- a/net/sunrpc/xprtrdma/xprt_rdma.h +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -334,7 +334,9 @@ struct rpcrdma_stats { /* * Per-registration mode operations */ +struct rpcrdma_xprt; struct rpcrdma_memreg_ops { + size_t (*ro_maxpages)(struct rpcrdma_xprt *); const char *ro_displayname; }; @@ -411,6 +413,8 @@ struct rpcrdma_regbuf *rpcrdma_alloc_regbuf(struct rpcrdma_ia *, void rpcrdma_free_regbuf(struct rpcrdma_ia *, struct rpcrdma_regbuf *); +unsigned int rpcrdma_max_segments(struct rpcrdma_xprt *); + /* * RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c */ @@ -422,7 +426,6 @@ void rpcrdma_reply_handler(struct rpcrdma_rep *); * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c */ int rpcrdma_marshal_req(struct rpc_rqst *); -size_t rpcrdma_max_payload(struct rpcrdma_xprt *); /* Temporary NFS request map cache. Created in svc_rdma.c */ extern struct kmem_cache *svc_rdma_map_cachep;