From 89d2d9fbeadcbdbd6302d3d0cd6bfbe219d85b68 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 19 Jul 2023 14:31:22 -0400 Subject: [PATCH] SUNRPC: Revert e0a912e8ddba Flamegraph analysis showed that the cork/uncork calls consume nearly a third of the CPU time spent in svc_tcp_sendto(). The other two consumers are mutex lock/unlock and svc_tcp_sendmsg(). Now that svc_tcp_sendto() coalesces RPC messages properly, there is no need to introduce artificial delays to prevent sending partial messages. After applying this change, I measured a 1.2K read IOPS increase for 8KB random I/O (several percent) on 56Gb IP over IB. Reviewed-by: David Howells Signed-off-by: Chuck Lever --- include/linux/sunrpc/svcsock.h | 2 -- net/sunrpc/svcsock.c | 6 ------ 2 files changed, 8 deletions(-) diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h index caf3308f1f07e..a7ea54460b1a6 100644 --- a/include/linux/sunrpc/svcsock.h +++ b/include/linux/sunrpc/svcsock.h @@ -35,8 +35,6 @@ 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_frag_cache sk_frag_cache; diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 2ff730335a56c..8db8227e6c834 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -1268,22 +1268,17 @@ static int svc_tcp_sendto(struct svc_rqst *rqstp) svc_tcp_release_ctxt(xprt, rqstp->rq_xprt_ctxt); rqstp->rq_xprt_ctxt = NULL; - 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, rqstp, marker, &sent); trace_svcsock_tcp_send(xprt, err < 0 ? (long)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: @@ -1292,7 +1287,6 @@ out_close: (err < 0) ? "got error" : "sent", (err < 0) ? err : sent, xdr->len); svc_xprt_deferred_close(xprt); - atomic_dec(&svsk->sk_sendqlen); mutex_unlock(&xprt->xpt_mutex); return -EAGAIN; } -- 2.30.2