From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 99576C369A1 for ; Tue, 8 Apr 2025 11:27:55 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1u275s-0007b9-Fb; Tue, 08 Apr 2025 07:26:16 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1u275p-0007aZ-Nz for qemu-devel@nongnu.org; Tue, 08 Apr 2025 07:26:14 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1u275n-0006OZ-Pv for qemu-devel@nongnu.org; Tue, 08 Apr 2025 07:26:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1744111571; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Yq+SSWaeQzXTk76xvI7u2atw8L3iFrBBMkDgz0BDY5k=; b=AV7Gi/VoZ/rgumToQwvB69nPvnFcqG6Oyt/c/xG0FaGM8kLFlYTkvUmvc7L6a5XceGg4OE tte4ocvtkjIi/xL/nPDQO90qQ0Hs0zLonpameoFEng/yS2r6TuVfDAF5Cb/bF4h0krWB03 SEYaFxFRuMnUKRyGVbrzdcAFDociyIc= Received: from mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-198-oqIzsSJPM3qH1lzLqmJ_Yw-1; Tue, 08 Apr 2025 07:26:09 -0400 X-MC-Unique: oqIzsSJPM3qH1lzLqmJ_Yw-1 X-Mimecast-MFC-AGG-ID: oqIzsSJPM3qH1lzLqmJ_Yw_1744111568 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id B42A419560AB; Tue, 8 Apr 2025 11:26:08 +0000 (UTC) Received: from rh-jmarcin.redhat.com (unknown [10.44.34.27]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 6D9AB195DF84; Tue, 8 Apr 2025 11:26:05 +0000 (UTC) From: Juraj Marcin To: qemu-devel@nongnu.org Cc: Juraj Marcin , vsementsov@yandex-team.ru, =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= , Paolo Bonzini Subject: [PATCH v3 5/5] utils/qemu-sockets: Introduce inet socket options controlling TCP keep-alive Date: Tue, 8 Apr 2025 13:25:04 +0200 Message-ID: <20250408112508.1638722-6-jmarcin@redhat.com> In-Reply-To: <20250408112508.1638722-1-jmarcin@redhat.com> References: <20250408112508.1638722-1-jmarcin@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 Received-SPF: pass client-ip=170.10.133.124; envelope-from=jmarcin@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.845, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Juraj Marcin With the default TCP stack configuration, it could be even 2 hours before the connection times out due to the other side not being reachable. However, in some cases, the application needs to be aware of a connection issue much sooner. This is the case, for example, for postcopy live migration. If there is no traffic from the migration destination guest (server-side) to the migration source guest (client-side), the destination keeps waiting for pages indefinitely and does not switch to the postcopy-paused state. This can happen, for example, if the destination QEMU instance is started with the '-S' command line option and the machine is not started yet, or if the machine is idle and produces no new page faults for not-yet-migrated pages. This patch introduces new inet socket parameters that control count, idle period, and interval of TCP keep-alive packets before the connection is considered broken. These parameters are available on systems where the respective TCP socket options are defined (TCP_KEEPCNT, TCP_KEEPIDLE, TCP_KEEPINTVL). The default value for all is 0, which means the system configuration is used. Signed-off-by: Juraj Marcin --- meson.build | 6 ++++ qapi/sockets.json | 15 ++++++++ util/qemu-sockets.c | 88 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 109 insertions(+) diff --git a/meson.build b/meson.build index 41f68d3806..680f47cf42 100644 --- a/meson.build +++ b/meson.build @@ -2734,6 +2734,12 @@ if linux_io_uring.found() config_host_data.set('HAVE_IO_URING_PREP_WRITEV2', cc.has_header_symbol('liburing.h', 'io_uring_prep_writev2')) endif +config_host_data.set('HAVE_TCP_KEEPCNT', + cc.has_header_symbol('netinet/tcp.h', 'TCP_KEEPCNT')) +config_host_data.set('HAVE_TCP_KEEPIDLE', + cc.has_header_symbol('netinet/tcp.h', 'TCP_KEEPIDLE')) +config_host_data.set('HAVE_TCP_KEEPINTVL', + cc.has_header_symbol('netinet/tcp.h', 'TCP_KEEPINTVL')) # has_member config_host_data.set('HAVE_SIGEV_NOTIFY_THREAD_ID', diff --git a/qapi/sockets.json b/qapi/sockets.json index 62797cd027..bb9d298635 100644 --- a/qapi/sockets.json +++ b/qapi/sockets.json @@ -59,6 +59,18 @@ # @keep-alive: enable keep-alive when connecting to/listening on this socket. # (Since 4.2, not supported for listening sockets until 10.1) # +# @keep-alive-count: number of keep-alive packets sent before the connection is +# closed. Only supported for TCP sockets on systems where TCP_KEEPCNT +# socket option is defined. (Since 10.1) +# +# @keep-alive-idle: time in seconds the connection needs to be idle before +# sending a keepalive packet. Only supported for TCP sockets on systems +# where TCP_KEEPIDLE socket option is defined. (Since 10.1) +# +# @keep-alive-interval: time in secods between keep-alive packets. Only +# supported for TCP sockets on systems where TCP_KEEPINTVL is defined. +# (Since 10.1) +# # @mptcp: enable multi-path TCP. (Since 6.1) # # Since: 1.3 @@ -71,6 +83,9 @@ '*ipv4': 'bool', '*ipv6': 'bool', '*keep-alive': 'bool', + '*keep-alive-count': { 'type': 'uint32', 'if': 'HAVE_TCP_KEEPCNT' }, + '*keep-alive-idle': { 'type': 'uint32', 'if': 'HAVE_TCP_KEEPIDLE' }, + '*keep-alive-interval': { 'type': 'uint32', 'if': 'HAVE_TCP_KEEPINTVL' }, '*mptcp': { 'type': 'bool', 'if': 'HAVE_IPPROTO_MPTCP' } } } ## diff --git a/util/qemu-sockets.c b/util/qemu-sockets.c index fed17a1ffb..8e355b097c 100644 --- a/util/qemu-sockets.c +++ b/util/qemu-sockets.c @@ -217,6 +217,45 @@ static int inet_set_sockopts(int sock, InetSocketAddress *saddr, Error **errp) "Unable to set keep-alive option on socket"); return -1; } +#ifdef HAVE_TCP_KEEPCNT + if (saddr->has_keep_alive_count && + saddr->keep_alive_count) { + int keep_count = saddr->has_keep_alive_count; + ret = setsockopt(sock, IPPROTO_TCP, TCP_KEEPCNT, &keep_count, + sizeof(keep_count)); + if (ret < 0) { + error_setg_errno(errp, errno, + "Unable to set TCP keep-alive count option on socket"); + return -1; + } + } +#endif +#ifdef HAVE_TCP_KEEPIDLE + if (saddr->has_keep_alive_idle && + saddr->keep_alive_idle) { + int keep_idle = saddr->has_keep_alive_idle; + ret = setsockopt(sock, IPPROTO_TCP, TCP_KEEPIDLE, &keep_idle, + sizeof(keep_idle)); + if (ret < 0) { + error_setg_errno(errp, errno, + "Unable to set TCP keep-alive idle option on socket"); + return -1; + } + } +#endif +#ifdef HAVE_TCP_KEEPINTVL + if (saddr->has_keep_alive_interval && + saddr->keep_alive_interval) { + int keep_interval = saddr->has_keep_alive_interval; + ret = setsockopt(sock, IPPROTO_TCP, TCP_KEEPINTVL, &keep_interval, + sizeof(keep_interval)); + if (ret < 0) { + error_setg_errno(errp, errno, + "Unable to set TCP keep-alive interval option on socket"); + return -1; + } + } +#endif } return 0; } @@ -628,6 +667,22 @@ static int inet_parse_flag(const char *flagname, const char *optstr, bool *val, return 0; } +static int inet_parse_u32(const char *optname, const char *optstr, + uint32_t max, uint32_t *val, Error **errp) +{ + int pos; + if (sscanf(optstr, "%" PRIu32 "%n", val, &pos) != 1 || + (optstr[pos] != '\0' && optstr[pos] != ',')) { + error_setg(errp, "error parsing %s argument", optname); + return -1; + } + if (*val > max) { + error_setg(errp, "%s is too large", optname); + return -1; + } + return 0; +} + int inet_parse(InetSocketAddress *addr, const char *str, Error **errp) { const char *optstr, *h; @@ -700,6 +755,39 @@ int inet_parse(InetSocketAddress *addr, const char *str, Error **errp) } addr->has_keep_alive = true; } +#ifdef HAVE_TCP_KEEPCNT + begin = strstr(optstr, ",keep-alive-count="); + if (begin) { + if (inet_parse_u32("keep-alive-count", + begin + strlen(",keep-alive-count="), INT_MAX, + &addr->keep_alive_count, errp)) { + return -1; + } + addr->has_keep_alive_count = true; + } +#endif +#ifdef HAVE_TCP_KEEPIDLE + begin = strstr(optstr, ",keep-alive-idle="); + if (begin) { + if (inet_parse_u32("keep-alive-idle", + begin + strlen(",keep-alive-idle="), INT_MAX, + &addr->keep_alive_idle, errp)) { + return -1; + } + addr->has_keep_alive_idle = true; + } +#endif +#ifdef HAVE_TCP_KEEPINTVL + begin = strstr(optstr, ",keep-alive-interval="); + if (begin) { + if (inet_parse_u32("keep-alive-interval", + begin + strlen(",keep-alive-interval="), INT_MAX, + &addr->keep_alive_interval, errp)) { + return -1; + } + addr->has_keep_alive_interval = true; + } +#endif #ifdef HAVE_IPPROTO_MPTCP begin = strstr(optstr, ",mptcp"); if (begin) { -- 2.48.1