From patchwork Wed May 26 16:07:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Abeni X-Patchwork-Id: 12282215 X-Patchwork-Delegate: mat@martineau.name Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 AF43770 for ; Wed, 26 May 2021 16:07:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1622045255; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=q9TASXkjYCOaCLRjEl7rDf96lqtgwY8FbmJcrQcT2F8=; b=A31UOFoR0Dw+iqKOlvNbsALKWHkptSLtYrouJMSphCtrJDG9yufRj5nApjnr3ok2Zfn2Au oPt4DjdBLFxCFnGpStB0NAUYjUtaLRBLeSygV0v0GkbK24CTTHmhdjOR3/qTH9WE+6CgGB FHi3wHH2El7IDZBfvCiXrqnLB9v/YAo= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-222-bbT_-oxRPt25q2kgu5iHiw-1; Wed, 26 May 2021 12:07:34 -0400 X-MC-Unique: bbT_-oxRPt25q2kgu5iHiw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4EEC6803645 for ; Wed, 26 May 2021 16:07:33 +0000 (UTC) Received: from gerbillo.redhat.com (ovpn-113-44.ams2.redhat.com [10.36.113.44]) by smtp.corp.redhat.com (Postfix) with ESMTP id B7A551ACB9 for ; Wed, 26 May 2021 16:07:32 +0000 (UTC) From: Paolo Abeni To: mptcp@lists.linux.dev Subject: [PATCH mptcp-next] mptcp: use fast lock for subflows when possible. Date: Wed, 26 May 2021 18:07:21 +0200 Message-Id: X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=pabeni@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com There are a bunch of callsite where the ssk socket lock is acquired using the full-blown version eligible for the fast variant. Let's move to the latter. Signed-off-by: Paolo Abeni Reviewed-by: Mat Martineau --- The previous patch demonstrated that using lock_sock() were the fast version is available can have worse side-effect than slower performances. This tries to address the topic. --- net/mptcp/pm_netlink.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index 09722598994d..d4732a4f223e 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -540,6 +540,7 @@ void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk) subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node); if (subflow) { struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + bool slow; spin_unlock_bh(&msk->pm.lock); pr_debug("send ack for %s%s%s", @@ -547,9 +548,9 @@ void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk) mptcp_pm_should_add_signal_ipv6(msk) ? " [ipv6]" : "", mptcp_pm_should_add_signal_port(msk) ? " [port]" : ""); - lock_sock(ssk); + slow = lock_sock_fast(ssk); tcp_send_ack(ssk); - release_sock(ssk); + unlock_sock_fast(ssk, slow); spin_lock_bh(&msk->pm.lock); } } @@ -566,6 +567,7 @@ int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, struct sock *ssk = mptcp_subflow_tcp_sock(subflow); struct sock *sk = (struct sock *)msk; struct mptcp_addr_info local; + bool slow; local_address((struct sock_common *)ssk, &local); if (!addresses_equal(&local, addr, addr->port)) @@ -578,9 +580,9 @@ int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, spin_unlock_bh(&msk->pm.lock); pr_debug("send ack for mp_prio"); - lock_sock(ssk); + slow = lock_sock_fast(ssk); tcp_send_ack(ssk); - release_sock(ssk); + unlock_sock_fast(ssk, slow); spin_lock_bh(&msk->pm.lock); return 0;