From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1608E2E0B4B for ; Thu, 11 Sep 2025 08:15:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757578519; cv=none; b=bSK2FgYAtXu4c+MoVZdcO019VCAhaRyb3BVfUHp4JJX7wieq3TedBPIsMqFzy6M0gOM8pGtF8y+SuAEFLi9ot3SEehUqfrviM8KBT3tHsP8mHKfqjvVqFgAfodJ5PNx5ENCTfiskSgMxW2c3Ut+CqSLbIxY2vg/RguUMsF2zdIQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757578519; c=relaxed/simple; bh=UWiLXvmKFwVyt5blNoKoJOQQOHUDV5nQy2aWT+wk60o=; h=Message-ID:Subject:From:To:Date:In-Reply-To:References: Content-Type:MIME-Version; b=Cy6SjnyGDSIR/at7eKovbKwMyUsRIAIfMgL0LiOP9w6dJct8dcDPJUS0hOPWxYpMm7kEqEBWVoEi0KynUnCYLz0BezEjE8/FxozTp0YdlC7T+UXU0NHuhxu+QowJ2TwAvGVd+WzPL4dBjMAxh3ApqVD31r2bLTPfV4UwBoc7pHc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=M+eY8xk/; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="M+eY8xk/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C8E13C4CEF8; Thu, 11 Sep 2025 08:15:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757578518; bh=UWiLXvmKFwVyt5blNoKoJOQQOHUDV5nQy2aWT+wk60o=; h=Subject:From:To:Date:In-Reply-To:References:From; b=M+eY8xk/RjhYzdiiHEPPHvCDJap7dnOUQ2uWvhm26UIq95jvVGX0o6mOPy+4dLALZ UE9XVN7gul5hL4HFhm5syluTpb/VPM2tu+sFyEF39UY/y7zS8GC9OsG4EWoJGyFOou U6kyjb2qRopkzJnFAxZu32jPbxkuKdkF1ahu/2Kq6kU/8h4bTBS6TMArOzOI6tOEDh DsGDz9PtWtIsvjUQ9shnUgI5NxSpBdZFVWYNTfd7OqdtdEcSUwXMbVMFb2uCGJP1cn boWkB66UEuZC8GblJdv8wbRmZmIc1D2BOwSvRX4vjjHDGhxZUl3NCHWTkcB4z81RJm sGHBLmWRkc7jw== Message-ID: <732d1d85e092148ff8d8d1c82f311929a5d53ff3.camel@kernel.org> Subject: Re: [PATCH mptcp-next 1/4] mptcp: pm: netlink: only add server-side attr when true From: Geliang Tang To: "Matthieu Baerts (NGI0)" , MPTCP Upstream Date: Thu, 11 Sep 2025 16:15:14 +0800 In-Reply-To: <20250909-mptcp-pm-user-server-side-flag-v1-1-cb8e2b8d1c0c@kernel.org> References: <20250909-mptcp-pm-user-server-side-flag-v1-0-cb8e2b8d1c0c@kernel.org> <20250909-mptcp-pm-user-server-side-flag-v1-1-cb8e2b8d1c0c@kernel.org> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.56.0-1 Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi Matt, On Tue, 2025-09-09 at 18:30 +0200, Matthieu Baerts (NGI0) wrote: > This attribute is a boolean. No need to add it to set it to 'false'. > > Indeed, the default value when this attribute is not set is naturally > 'false'. A few bytes can then be saved by not adding this attribute > if > the connection is not on the server side. > > This prepares the future deprecation of its attribute, in favour of a > new flag. > > Signed-off-by: Matthieu Baerts (NGI0) > --- >  Documentation/netlink/specs/mptcp_pm.yaml         | 4 ++-- >  include/uapi/linux/mptcp_pm.h                     | 4 ++-- >  net/mptcp/pm_netlink.c                            | 4 +++- >  tools/testing/selftests/net/mptcp/userspace_pm.sh | 2 +- >  4 files changed, 8 insertions(+), 6 deletions(-) > > diff --git a/Documentation/netlink/specs/mptcp_pm.yaml > b/Documentation/netlink/specs/mptcp_pm.yaml > index > d1b4829b580ad09baf4afd73b67abd7b4ef6883a..fc47a2931014c0304efd3215cc2 > 4485ea22e1ede 100644 > --- a/Documentation/netlink/specs/mptcp_pm.yaml > +++ b/Documentation/netlink/specs/mptcp_pm.yaml > @@ -28,13 +28,13 @@ definitions: >            traffic-patterns it can take a long time until the >            MPTCP_EVENT_ESTABLISHED is sent. >            Attributes: token, family, saddr4 | saddr6, daddr4 | > daddr6, sport, > -          dport, server-side, [flags]. > +          dport, [server-side], [flags]. >        - >          name: established >          doc: >- >            A MPTCP connection is established (can start new > subflows). >            Attributes: token, family, saddr4 | saddr6, daddr4 | > daddr6, sport, > -          dport, server-side, [flags]. > +          dport, [server-side], [flags]. >        - >          name: closed >          doc: >- > diff --git a/include/uapi/linux/mptcp_pm.h > b/include/uapi/linux/mptcp_pm.h > index > 7359d34da446b94be148b363079120db03ba8549..bf44a5cf5b5a1e6d789632682a9 > bedbf8090feb9 100644 > --- a/include/uapi/linux/mptcp_pm.h > +++ b/include/uapi/linux/mptcp_pm.h > @@ -16,10 +16,10 @@ >   *   good time to allocate memory and send ADD_ADDR if needed. > Depending on the >   *   traffic-patterns it can take a long time until the > MPTCP_EVENT_ESTABLISHED >   *   is sent. Attributes: token, family, saddr4 | saddr6, daddr4 | > daddr6, > - *   sport, dport, server-side, [flags]. > + *   sport, dport, [server-side], [flags]. >   * @MPTCP_EVENT_ESTABLISHED: A MPTCP connection is established (can > start new >   *   subflows). Attributes: token, family, saddr4 | saddr6, daddr4 | > daddr6, > - *   sport, dport, server-side, [flags]. > + *   sport, dport, [server-side], [flags]. >   * @MPTCP_EVENT_CLOSED: A MPTCP connection has stopped. Attribute: > token. >   * @MPTCP_EVENT_ANNOUNCED: A new address has been announced by the > peer. >   *   Attributes: token, rem_id, family, daddr4 | daddr6 [, dport]. > diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c > index > 483ddbb9ec406a3e965376ee5a833ae295896a02..33a6bf536c020b59717472aca2d > 38add26255419 100644 > --- a/net/mptcp/pm_netlink.c > +++ b/net/mptcp/pm_netlink.c > @@ -413,7 +413,9 @@ static int mptcp_event_created(struct sk_buff > *skb, >   if (err) >   return err; >   > - if (nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, READ_ONCE(msk- > >pm.server_side))) > + /* only set when it is the server side */ > + if (READ_ONCE(msk->pm.server_side) && > +     nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, 1)) In patch 2, this will be modified to use two 'if': if (READ_ONCE(msk->pm.server_side)) { flags |= MPTCP_PM_EV_FLAG_SERVER_SIDE; /* only set when it is the server side */ if (nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, 1)) return -EMSGSIZE; } Why don't we just use two 'if' statements here, which will make patch 2 simpler: if (READ_ONCE(msk->pm.server_side)) { /* only set when it is the server side */ if (nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, 1)) return -EMSGSIZE; } WDYT? Thanks, -Geliang >   return -EMSGSIZE; >   >   if (READ_ONCE(msk->pm.remote_deny_join_id0)) > diff --git a/tools/testing/selftests/net/mptcp/userspace_pm.sh > b/tools/testing/selftests/net/mptcp/userspace_pm.sh > index > 0801d57a9710406a5942af742719f694e3907558..189bfc5bf86611575381542fe59 > b86660f335294 100755 > --- a/tools/testing/selftests/net/mptcp/userspace_pm.sh > +++ b/tools/testing/selftests/net/mptcp/userspace_pm.sh > @@ -241,7 +241,7 @@ make_connection() >   >   print_test "Established IP${is_v6} MPTCP Connection ns2 => > ns1" >   if [ "${client_token}" != "" ] && [ "${server_token}" != "" > ] && > -    [ "${client_serverside}" = 0 ] && [ > "${server_serverside}" = 1 ] && > +    [ "${client_serverside:-0}" = 0 ] && [ > "${server_serverside:-0}" = 1 ] && >      [ "${client_nojoin:-0}" = 1 ] && [ "${server_nojoin:-0}" > = 0 ] >   then >   test_pass