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 X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 23800C33CB1 for ; Tue, 14 Jan 2020 09:32:17 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id E5210207FF for ; Tue, 14 Jan 2020 09:32:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Jo8tlm4V" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E5210207FF Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:35215 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1irIYZ-0003dP-CY for qemu-devel@archiver.kernel.org; Tue, 14 Jan 2020 04:32:15 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:57233) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1irITF-0004rh-V3 for qemu-devel@nongnu.org; Tue, 14 Jan 2020 04:26:47 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1irITE-0006Lc-CA for qemu-devel@nongnu.org; Tue, 14 Jan 2020 04:26:45 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:47547 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1irITE-0006LF-8u for qemu-devel@nongnu.org; Tue, 14 Jan 2020 04:26:44 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1578994003; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=KP4JOgx0MH3utU/6sKW0BXPz8/EvSkOonQGNpzhU5Ck=; b=Jo8tlm4VKFQSUw5TSjnLIgE2lv1HhYv3o/kj+gpx8sgtTo5nt9EH4Cw5IYluHKnu75Odos 87HQu55HTpKxgj4sgIBThGtvYsCJeKePYsrZHwCF8WbKipWNIr8R1GWWXDINNODKSa//2L afYLLcLWwB/NkaIYEJ7iIZm+xONbElQ= 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-21-qOq3OrIYMoK77FdzsY6GQg-1; Tue, 14 Jan 2020 04:26:37 -0500 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id EA3A6107ACC4; Tue, 14 Jan 2020 09:26:35 +0000 (UTC) Received: from secure.mitica (ovpn-116-207.ams2.redhat.com [10.36.116.207]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0DA2019757; Tue, 14 Jan 2020 09:26:26 +0000 (UTC) From: Juan Quintela To: qemu-devel@nongnu.org Subject: [PULL 03/29] migration: Make sure that we don't call write() in case of error Date: Tue, 14 Jan 2020 10:25:40 +0100 Message-Id: <20200114092606.1761-4-quintela@redhat.com> In-Reply-To: <20200114092606.1761-1-quintela@redhat.com> References: <20200114092606.1761-1-quintela@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-MC-Unique: qOq3OrIYMoK77FdzsY6GQg-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Laurent Vivier , Corey Minyard , Thomas Huth , =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= , Eduardo Habkost , "Michael S. Tsirkin" , Peter Maydell , Stefan Weil , Jason Wang , Juan Quintela , "Dr. David Alan Gilbert" , qemu-arm@nongnu.org, qemu-ppc@nongnu.org, =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Paolo Bonzini , David Gibson , Richard Henderson , Stefan Berger Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" If we are exiting due to an error/finish/.... Just don't try to even touch the channel with one IO operation. Signed-off-by: Juan Quintela Reviewed-by: Dr. David Alan Gilbert --- migration/ram.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/migration/ram.c b/migration/ram.c index b9147bcca3..f946282adb 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -900,6 +900,12 @@ struct { uint64_t packet_num; /* send channels ready */ QemuSemaphore channels_ready; + /* + * Have we already run terminate threads. There is a race when it + * happens that we got one error while we are exiting. + * We will use atomic operations. Only valid values are 0 and 1. + */ + int exiting; } *multifd_send_state; =20 /* @@ -928,6 +934,10 @@ static int multifd_send_pages(RAMState *rs) MultiFDPages_t *pages =3D multifd_send_state->pages; uint64_t transferred; =20 + if (atomic_read(&multifd_send_state->exiting)) { + return -1; + } + qemu_sem_wait(&multifd_send_state->channels_ready); for (i =3D next_channel;; i =3D (i + 1) % migrate_multifd_channels()) = { p =3D &multifd_send_state->params[i]; @@ -1009,6 +1019,16 @@ static void multifd_send_terminate_threads(Error *er= r) } } =20 + /* + * We don't want to exit each threads twice. Depending on where + * we get the error, or if there are two independent errors in two + * threads at the same time, we can end calling this function + * twice. + */ + if (atomic_xchg(&multifd_send_state->exiting, 1)) { + return; + } + for (i =3D 0; i < migrate_multifd_channels(); i++) { MultiFDSendParams *p =3D &multifd_send_state->params[i]; =20 @@ -1118,6 +1138,10 @@ static void *multifd_send_thread(void *opaque) =20 while (true) { qemu_sem_wait(&p->sem); + + if (atomic_read(&multifd_send_state->exiting)) { + break; + } qemu_mutex_lock(&p->mutex); =20 if (p->pending_job) { @@ -1224,6 +1248,7 @@ int multifd_save_setup(void) multifd_send_state->params =3D g_new0(MultiFDSendParams, thread_count)= ; multifd_send_state->pages =3D multifd_pages_init(page_count); qemu_sem_init(&multifd_send_state->channels_ready, 0); + atomic_set(&multifd_send_state->exiting, 0); =20 for (i =3D 0; i < thread_count; i++) { MultiFDSendParams *p =3D &multifd_send_state->params[i]; --=20 2.24.1