From e0a912e8ddbaa0536352dd8318845cdfdbab7bab Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 16 Feb 2021 12:17:22 -0500 Subject: [PATCH] SUNRPC: Use TCP_CORK to optimise send performance on the server Use a counter to keep track of how many requests are queued behind the xprt->xpt_mutex, and keep TCP_CORK set until the queue is empty. Signed-off-by: Trond Myklebust Link: https://lore.kernel.org/linux-nfs/20210213202532.23146-1-trondmy@kernel.org/T/#u Signed-off-by: Chuck Lever --- include/linux/sunrpc/svcsock.h | 2 ++ net/sunrpc/svcsock.c | 8 +++++++- 2 files changed, 9 insertions(+), 1 deletion(-) diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h index b7ac7fe68306..bcc555c7ae9c 100644 --- a/include/linux/sunrpc/svcsock.h +++ b/include/linux/sunrpc/svcsock.h @@ -35,6 +35,8 @@ struct svc_sock { /* Total length of the data (not including fragment headers) * received so far in the fragments making up this rpc: */ u32 sk_datalen; + /* Number of queued send requests */ + atomic_t sk_sendqlen; struct page * sk_pages[RPCSVC_MAXPAGES]; /* received data */ }; diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 5a809c64dc7b..231f510a4830 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -1171,18 +1171,23 @@ static int svc_tcp_sendto(struct svc_rqst *rqstp) svc_tcp_release_rqst(rqstp); + atomic_inc(&svsk->sk_sendqlen); mutex_lock(&xprt->xpt_mutex); if (svc_xprt_is_dead(xprt)) goto out_notconn; + tcp_sock_set_cork(svsk->sk_sk, true); err = svc_tcp_sendmsg(svsk->sk_sock, &msg, xdr, marker, &sent); xdr_free_bvec(xdr); trace_svcsock_tcp_send(xprt, err < 0 ? err : sent); if (err < 0 || sent != (xdr->len + sizeof(marker))) goto out_close; + if (atomic_dec_and_test(&svsk->sk_sendqlen)) + tcp_sock_set_cork(svsk->sk_sk, false); mutex_unlock(&xprt->xpt_mutex); return sent; out_notconn: + atomic_dec(&svsk->sk_sendqlen); mutex_unlock(&xprt->xpt_mutex); return -ENOTCONN; out_close: @@ -1192,6 +1197,7 @@ out_close: (err < 0) ? err : sent, xdr->len); set_bit(XPT_CLOSE, &xprt->xpt_flags); svc_xprt_enqueue(xprt); + atomic_dec(&svsk->sk_sendqlen); mutex_unlock(&xprt->xpt_mutex); return -EAGAIN; } @@ -1261,7 +1267,7 @@ static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv) svsk->sk_datalen = 0; memset(&svsk->sk_pages[0], 0, sizeof(svsk->sk_pages)); - tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF; + tcp_sock_set_nodelay(sk); set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); switch (sk->sk_state) {