From nobody Mon Feb 9 16:32:40 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 684CCC001B0 for ; Wed, 19 Jul 2023 19:33:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229688AbjGSTdP (ORCPT ); Wed, 19 Jul 2023 15:33:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56022 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231304AbjGSTc7 (ORCPT ); Wed, 19 Jul 2023 15:32:59 -0400 Received: from mx1.sberdevices.ru (mx1.sberdevices.ru [37.18.73.165]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2C8631FEC; Wed, 19 Jul 2023 12:32:49 -0700 (PDT) Received: from p-infra-ksmg-sc-msk01 (localhost [127.0.0.1]) by mx1.sberdevices.ru (Postfix) with ESMTP id 792CF100003; Wed, 19 Jul 2023 22:32:47 +0300 (MSK) DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.sberdevices.ru 792CF100003 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sberdevices.ru; s=mail; t=1689795167; bh=R8LKwJhTgv7AdmVqAkaUUGs73U74AWbG/gmK+1it7D0=; h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type:From; b=IwtNdRVtoU5eeLKJ/6sanhguDxXjZa0Uhj8aHd0eZjRQ0Olu5nJxlj6j/RJXKhLjR RhkGA4C9xiYyEiTgnE7o3gQ7DUxFSXxh+Tbj3vEzCDBaBtOjQmD2JDIQDS992s/rLs Ot1fExUC2xlBJdhZe5v9oGL/6qg+w9hPuuEMwdxdY5AoIFn9NQIb592SS2xUjTN2qD Q/CbrvakHwQuQUde0sKwnOccm++ja2IMFS91HsjyGX4wiiJO/z8M5ylJjKyEzeCK8B Ow2kHK6KMPfNgc6i4hxtZJKev4xdEc47iMuZj2xccq2j9Kn797TlIXAZUmAkGOruuK YUgQkIjUw6Mzg== Received: from p-i-exch-sc-m01.sberdevices.ru (p-i-exch-sc-m01.sberdevices.ru [172.16.192.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.sberdevices.ru (Postfix) with ESMTPS; Wed, 19 Jul 2023 22:32:47 +0300 (MSK) Received: from localhost.localdomain (100.64.160.123) by p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.30; Wed, 19 Jul 2023 22:32:46 +0300 From: Arseniy Krasnov To: Stefan Hajnoczi , Stefano Garzarella , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , "Michael S. Tsirkin" , Jason Wang , Bobby Eshleman CC: , , , , , , , Arseniy Krasnov Subject: [RFC PATCH v2 1/4] virtio/vsock: rework MSG_PEEK for SOCK_STREAM Date: Wed, 19 Jul 2023 22:27:05 +0300 Message-ID: <20230719192708.1775162-2-AVKrasnov@sberdevices.ru> X-Mailer: git-send-email 2.35.0 In-Reply-To: <20230719192708.1775162-1-AVKrasnov@sberdevices.ru> References: <20230719192708.1775162-1-AVKrasnov@sberdevices.ru> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [100.64.160.123] X-ClientProxiedBy: p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) To p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) X-KSMG-Rule-ID: 10 X-KSMG-Message-Action: clean X-KSMG-AntiSpam-Lua-Profiles: 178730 [Jul 19 2023] X-KSMG-AntiSpam-Version: 5.9.59.0 X-KSMG-AntiSpam-Envelope-From: AVKrasnov@sberdevices.ru X-KSMG-AntiSpam-Rate: 0 X-KSMG-AntiSpam-Status: not_detected X-KSMG-AntiSpam-Method: none X-KSMG-AntiSpam-Auth: dkim=none X-KSMG-AntiSpam-Info: LuaCore: 524 524 9753033d6953787301affc41bead8ed49c47b39d, {Tracking_from_domain_doesnt_match_to}, d41d8cd98f00b204e9800998ecf8427e.com:7.1.1;127.0.0.199:7.1.2;p-i-exch-sc-m01.sberdevices.ru:7.1.1,5.0.1;sberdevices.ru:7.1.1,5.0.1;100.64.160.123:7.1.2, FromAlignment: s, {Tracking_white_helo}, ApMailHostAddress: 100.64.160.123 X-MS-Exchange-Organization-SCL: -1 X-KSMG-AntiSpam-Interceptor-Info: scan successful X-KSMG-AntiPhishing: Clean X-KSMG-LinksScanning: Clean X-KSMG-AntiVirus: Kaspersky Secure Mail Gateway, version 2.0.1.6960, bases: 2023/07/19 15:29:00 #21641898 X-KSMG-AntiVirus-Status: Clean, skipped Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" This reworks current implementation of MSG_PEEK logic: 1) Replaces 'skb_queue_walk_safe()' with 'skb_queue_walk()'. There is no need in the first one, as there are no removes of skb in loop. 2) Removes nested while loop - MSG_PEEK logic could be implemented without it: just iterate over skbs without removing it and copy data from each until destination buffer is not full. Signed-off-by: Arseniy Krasnov Reviewed-by: Bobby Eshleman Reviewed-by: Stefano Garzarella --- net/vmw_vsock/virtio_transport_common.c | 41 ++++++++++++------------- 1 file changed, 19 insertions(+), 22 deletions(-) diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio= _transport_common.c index b769fc258931..2ee40574c339 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -348,37 +348,34 @@ virtio_transport_stream_do_peek(struct vsock_sock *vs= k, size_t len) { struct virtio_vsock_sock *vvs =3D vsk->trans; - size_t bytes, total =3D 0, off; - struct sk_buff *skb, *tmp; - int err =3D -EFAULT; + struct sk_buff *skb; + size_t total =3D 0; + int err; =20 spin_lock_bh(&vvs->rx_lock); =20 - skb_queue_walk_safe(&vvs->rx_queue, skb, tmp) { - off =3D 0; + skb_queue_walk(&vvs->rx_queue, skb) { + size_t bytes; =20 - if (total =3D=3D len) - break; + bytes =3D len - total; + if (bytes > skb->len) + bytes =3D skb->len; =20 - while (total < len && off < skb->len) { - bytes =3D len - total; - if (bytes > skb->len - off) - bytes =3D skb->len - off; + spin_unlock_bh(&vvs->rx_lock); =20 - /* sk_lock is held by caller so no one else can dequeue. - * Unlock rx_lock since memcpy_to_msg() may sleep. - */ - spin_unlock_bh(&vvs->rx_lock); + /* sk_lock is held by caller so no one else can dequeue. + * Unlock rx_lock since memcpy_to_msg() may sleep. + */ + err =3D memcpy_to_msg(msg, skb->data, bytes); + if (err) + goto out; =20 - err =3D memcpy_to_msg(msg, skb->data + off, bytes); - if (err) - goto out; + total +=3D bytes; =20 - spin_lock_bh(&vvs->rx_lock); + spin_lock_bh(&vvs->rx_lock); =20 - total +=3D bytes; - off +=3D bytes; - } + if (total =3D=3D len) + break; } =20 spin_unlock_bh(&vvs->rx_lock); --=20 2.25.1