From 1570c1e41eabf6b7031f3e4322a2cf1cbe319fee Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 25 Aug 2005 16:25:52 -0700 Subject: [PATCH] [PATCH] RPC: add generic interface for adjusting the congestion window A new interface that allows transports to adjust their congestion window using the Van Jacobson implementation in xprt.c is provided. Test-plan: Use WAN simulation to cause sporadic bursty packet loss. Look for significant regression in performance or client stability. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- include/linux/sunrpc/xprt.h | 3 +- net/sunrpc/xprt.c | 66 +++++++++++++++---------------------- net/sunrpc/xprtsock.c | 13 +++----- 3 files changed, 33 insertions(+), 49 deletions(-) diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h index 443c3f984cf..2e48752d55d 100644 --- a/include/linux/sunrpc/xprt.h +++ b/include/linux/sunrpc/xprt.h @@ -258,9 +258,10 @@ void xprt_set_retrans_timeout_rtt(struct rpc_task *task); void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status); void xprt_wait_for_buffer_space(struct rpc_task *task); void xprt_write_space(struct rpc_xprt *xprt); +void xprt_update_rtt(struct rpc_task *task); void xprt_adjust_cwnd(struct rpc_task *task, int result); struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid); -void xprt_complete_rqst(struct rpc_xprt *xprt, struct rpc_rqst *req, int copied); +void xprt_complete_rqst(struct rpc_task *task, int copied); void xprt_disconnect(struct rpc_xprt *xprt); /* diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index ffc595592af..707806fe1a2 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -591,56 +591,42 @@ struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid) return req; } +/** + * xprt_update_rtt - update an RPC client's RTT state after receiving a reply + * @task: RPC request that recently completed + * + */ +void xprt_update_rtt(struct rpc_task *task) +{ + struct rpc_rqst *req = task->tk_rqstp; + struct rpc_rtt *rtt = task->tk_client->cl_rtt; + unsigned timer = task->tk_msg.rpc_proc->p_timer; + + if (timer) { + if (req->rq_ntrans == 1) + rpc_update_rtt(rtt, timer, + (long)jiffies - req->rq_xtime); + rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); + } +} + /** * xprt_complete_rqst - called when reply processing is complete - * @xprt: controlling transport - * @req: RPC request that just completed + * @task: RPC request that recently completed * @copied: actual number of bytes received from the transport * + * Caller holds transport lock. */ -void xprt_complete_rqst(struct rpc_xprt *xprt, struct rpc_rqst *req, int copied) -{ - struct rpc_task *task = req->rq_task; - struct rpc_clnt *clnt = task->tk_client; - - /* Adjust congestion window */ - if (!xprt->nocong) { - unsigned timer = task->tk_msg.rpc_proc->p_timer; - xprt_adjust_cwnd(task, copied); - if (timer) { - if (req->rq_ntrans == 1) - rpc_update_rtt(clnt->cl_rtt, timer, - (long)jiffies - req->rq_xtime); - rpc_set_timeo(clnt->cl_rtt, timer, req->rq_ntrans - 1); - } - } +void xprt_complete_rqst(struct rpc_task *task, int copied) +{ + struct rpc_rqst *req = task->tk_rqstp; -#ifdef RPC_PROFILE - /* Profile only reads for now */ - if (copied > 1024) { - static unsigned long nextstat; - static unsigned long pkt_rtt, pkt_len, pkt_cnt; - - pkt_cnt++; - pkt_len += req->rq_slen + copied; - pkt_rtt += jiffies - req->rq_xtime; - if (time_before(nextstat, jiffies)) { - printk("RPC: %lu %ld cwnd\n", jiffies, xprt->cwnd); - printk("RPC: %ld %ld %ld %ld stat\n", - jiffies, pkt_cnt, pkt_len, pkt_rtt); - pkt_rtt = pkt_len = pkt_cnt = 0; - nextstat = jiffies + 5 * HZ; - } - } -#endif + dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", + task->tk_pid, ntohl(req->rq_xid), copied); - dprintk("RPC: %4d has input (%d bytes)\n", task->tk_pid, copied); list_del_init(&req->rq_list); req->rq_received = req->rq_private_buf.len = copied; - - /* ... and wake up the process. */ rpc_wake_up_task(task); - return; } static void xprt_timer(struct rpc_task *task) diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index c3658ff027a..980f26504f4 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -460,8 +460,6 @@ static void xs_udp_data_ready(struct sock *sk, int len) goto out_unlock; task = rovr->rq_task; - dprintk("RPC: %4d received reply\n", task->tk_pid); - if ((copied = rovr->rq_private_buf.buflen) > repsize) copied = repsize; @@ -472,7 +470,9 @@ static void xs_udp_data_ready(struct sock *sk, int len) /* Something worked... */ dst_confirm(skb->dst); - xprt_complete_rqst(xprt, rovr, copied); + xprt_adjust_cwnd(task, copied); + xprt_update_rtt(task); + xprt_complete_rqst(task, copied); out_unlock: spin_unlock(&xprt->transport_lock); @@ -634,11 +634,8 @@ static inline void xs_tcp_read_request(struct rpc_xprt *xprt, skb_reader_t *desc } out: - if (!(xprt->tcp_flags & XPRT_COPY_DATA)) { - dprintk("RPC: %4d received reply complete\n", - req->rq_task->tk_pid); - xprt_complete_rqst(xprt, req, xprt->tcp_copied); - } + if (!(xprt->tcp_flags & XPRT_COPY_DATA)) + xprt_complete_rqst(req->rq_task, xprt->tcp_copied); spin_unlock(&xprt->transport_lock); xs_tcp_check_recm(xprt); } -- 2.20.1