From patchwork Wed Aug 26 10:47:04 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kiszka X-Patchwork-Id: 32122 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [199.232.76.165]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by bilbo.ozlabs.org (Postfix) with ESMTPS id 49EE8B6F1F for ; Wed, 26 Aug 2009 20:48:08 +1000 (EST) Received: from localhost ([127.0.0.1]:43544 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MgG2r-0000Gz-Vz for incoming@patchwork.ozlabs.org; Wed, 26 Aug 2009 06:48:02 -0400 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MgG28-0000Eg-Sd for qemu-devel@nongnu.org; Wed, 26 Aug 2009 06:47:16 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MgG23-00009v-54 for qemu-devel@nongnu.org; Wed, 26 Aug 2009 06:47:15 -0400 Received: from [199.232.76.173] (port=44223 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MgG22-00009b-Jb for qemu-devel@nongnu.org; Wed, 26 Aug 2009 06:47:10 -0400 Received: from thoth.sbs.de ([192.35.17.2]:18809) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1MgG21-0001u1-LM for qemu-devel@nongnu.org; Wed, 26 Aug 2009 06:47:10 -0400 Received: from mail1.siemens.de (localhost [127.0.0.1]) by thoth.sbs.de (8.12.11.20060308/8.12.11) with ESMTP id n7QAl5xo022823; Wed, 26 Aug 2009 12:47:05 +0200 Received: from [139.25.109.167] (mchn012c.mchp.siemens.de [139.25.109.167] (may be forged)) by mail1.siemens.de (8.12.11.20060308/8.12.11) with ESMTP id n7QAl4Y1029312; Wed, 26 Aug 2009 12:47:05 +0200 Message-ID: <4A9512A8.1070709@siemens.com> Date: Wed, 26 Aug 2009 12:47:04 +0200 From: Jan Kiszka User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); de; rv:1.8.1.12) Gecko/20080226 SUSE/2.0.0.12-1.1 Thunderbird/2.0.0.12 Mnenhy/0.7.5.666 MIME-Version: 1.0 To: Anthony Liguori X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.4-2.6 Cc: Mark McLoughlin , qemu-devel Subject: [Qemu-devel] [PATCH] net: Fix send queue ordering X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Ensure that packets enqueued for delayed delivery are dequeued in FIFO order. At least one simplistic guest TCP/IP stack became unhappy due to sporadically reordered packet streams. At this chance, switch the send queue implementation to TAILQ. Signed-off-by: Jan Kiszka --- net.c | 29 ++++++++++++----------------- net.h | 5 +++-- 2 files changed, 15 insertions(+), 19 deletions(-) diff --git a/net.c b/net.c index 1b531e7..d7a1ab6 100644 --- a/net.c +++ b/net.c @@ -436,33 +436,28 @@ qemu_deliver_packet(VLANClientState *sender, const uint8_t *buf, int size) void qemu_purge_queued_packets(VLANClientState *vc) { - VLANPacket **pp = &vc->vlan->send_queue; - - while (*pp != NULL) { - VLANPacket *packet = *pp; + VLANPacket *packet, *next; + TAILQ_FOREACH_SAFE(packet, &vc->vlan->send_queue, entry, next) { if (packet->sender == vc) { - *pp = packet->next; + TAILQ_REMOVE(&vc->vlan->send_queue, packet, entry); qemu_free(packet); - } else { - pp = &packet->next; } } } void qemu_flush_queued_packets(VLANClientState *vc) { - VLANPacket *packet; - - while ((packet = vc->vlan->send_queue) != NULL) { + while (!TAILQ_EMPTY(&vc->vlan->send_queue)) { + VLANPacket *packet; int ret; - vc->vlan->send_queue = packet->next; + packet = TAILQ_FIRST(&vc->vlan->send_queue); + TAILQ_REMOVE(&vc->vlan->send_queue, packet, entry); ret = qemu_deliver_packet(packet->sender, packet->data, packet->size); if (ret == 0 && packet->sent_cb != NULL) { - packet->next = vc->vlan->send_queue; - vc->vlan->send_queue = packet; + TAILQ_INSERT_HEAD(&vc->vlan->send_queue, packet, entry); break; } @@ -480,12 +475,12 @@ static void qemu_enqueue_packet(VLANClientState *sender, VLANPacket *packet; packet = qemu_malloc(sizeof(VLANPacket) + size); - packet->next = sender->vlan->send_queue; packet->sender = sender; packet->size = size; packet->sent_cb = sent_cb; memcpy(packet->data, buf, size); - sender->vlan->send_queue = packet; + + TAILQ_INSERT_TAIL(&sender->vlan->send_queue, packet, entry); } ssize_t qemu_send_packet_async(VLANClientState *sender, @@ -597,7 +592,6 @@ static ssize_t qemu_enqueue_packet_iov(VLANClientState *sender, max_len = calc_iov_length(iov, iovcnt); packet = qemu_malloc(sizeof(VLANPacket) + max_len); - packet->next = sender->vlan->send_queue; packet->sender = sender; packet->sent_cb = sent_cb; packet->size = 0; @@ -609,7 +603,7 @@ static ssize_t qemu_enqueue_packet_iov(VLANClientState *sender, packet->size += len; } - sender->vlan->send_queue = packet; + TAILQ_INSERT_TAIL(&sender->vlan->send_queue, packet, entry); return packet->size; } @@ -2330,6 +2324,7 @@ VLANState *qemu_find_vlan(int id, int allocate) } vlan = qemu_mallocz(sizeof(VLANState)); vlan->id = id; + TAILQ_INIT(&vlan->send_queue); vlan->next = NULL; pvlan = &first_vlan; while (*pvlan != NULL) diff --git a/net.h b/net.h index 3ac9e8c..bab02f5 100644 --- a/net.h +++ b/net.h @@ -1,6 +1,7 @@ #ifndef QEMU_NET_H #define QEMU_NET_H +#include "sys-queue.h" #include "qemu-common.h" /* VLANs support */ @@ -35,7 +36,7 @@ typedef struct VLANPacket VLANPacket; typedef void (NetPacketSent) (VLANClientState *, ssize_t); struct VLANPacket { - struct VLANPacket *next; + TAILQ_ENTRY(VLANPacket) entry; VLANClientState *sender; int size; NetPacketSent *sent_cb; @@ -47,7 +48,7 @@ struct VLANState { VLANClientState *first_client; struct VLANState *next; unsigned int nb_guest_devs, nb_host_devs; - VLANPacket *send_queue; + TAILQ_HEAD(send_queue, VLANPacket) send_queue; int delivering; };