From 6760c47aa42ce30efdd12c132f73c8749c575995 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Mon, 15 Apr 2013 16:14:46 +0200 Subject: nbd: unlock mutex in nbd_co_send_request() error path Cc: qemu-stable@nongnu.org Signed-off-by: Stefan Hajnoczi Signed-off-by: Paolo Bonzini --- block/nbd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'block') diff --git a/block/nbd.c b/block/nbd.c index eff683c..662df16 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -339,7 +339,7 @@ static int nbd_co_send_request(BDRVNBDState *s, struct nbd_request *request, ret = qemu_co_sendv(s->sock, qiov->iov, qiov->niov, offset, request->len); if (ret != request->len) { - return -EIO; + rc = -EIO; } } qemu_aio_set_fd_handler(s->sock, nbd_reply_ready, NULL, -- cgit v1.1 From 0fcece25c0b1b79b39d1dff5c2c55b88feae7eef Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Mon, 15 Apr 2013 16:14:47 +0200 Subject: nbd: use TCP_CORK in nbd_co_send_request() Use TCP_CORK to defer packet transmission until both the header and the payload have been written. Suggested-by: Nick Thomas Signed-off-by: Stefan Hajnoczi Signed-off-by: Paolo Bonzini --- block/nbd.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) (limited to 'block') diff --git a/block/nbd.c b/block/nbd.c index 662df16..485bbf0 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -334,13 +334,23 @@ static int nbd_co_send_request(BDRVNBDState *s, struct nbd_request *request, s->send_coroutine = qemu_coroutine_self(); qemu_aio_set_fd_handler(s->sock, nbd_reply_ready, nbd_restart_write, nbd_have_request, s); - rc = nbd_send_request(s->sock, request); - if (rc >= 0 && qiov) { - ret = qemu_co_sendv(s->sock, qiov->iov, qiov->niov, - offset, request->len); - if (ret != request->len) { - rc = -EIO; + if (qiov) { + if (!s->is_unix) { + socket_set_cork(s->sock, 1); } + rc = nbd_send_request(s->sock, request); + if (rc >= 0) { + ret = qemu_co_sendv(s->sock, qiov->iov, qiov->niov, + offset, request->len); + if (ret != request->len) { + rc = -EIO; + } + } + if (!s->is_unix) { + socket_set_cork(s->sock, 0); + } + } else { + rc = nbd_send_request(s->sock, request); } qemu_aio_set_fd_handler(s->sock, nbd_reply_ready, NULL, nbd_have_request, s); -- cgit v1.1 From 97ebbab0e324831dff47dbfa4bed55808cb3ec74 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Mon, 15 Apr 2013 16:14:48 +0200 Subject: nbd: set TCP_NODELAY Disable the Nagle algorithm to reduce latency. Note this means we must also use TCP_CORK when sending header followed by payload to avoid fragmenting lots of little packets. The previous patch took care of that. Suggested-by: Nick Thomas Tested-by: Nick Thomas Signed-off-by: Stefan Hajnoczi Signed-off-by: Paolo Bonzini --- block/nbd.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'block') diff --git a/block/nbd.c b/block/nbd.c index 485bbf0..d9dc454 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -406,6 +406,9 @@ static int nbd_establish_connection(BlockDriverState *bs) sock = unix_socket_outgoing(qemu_opt_get(s->socket_opts, "path")); } else { sock = tcp_socket_outgoing_opts(s->socket_opts); + if (sock >= 0) { + socket_set_nodelay(sock); + } } /* Failed to establish connection */ -- cgit v1.1