From nobody Tue Feb 10 06:25:13 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1578677910; cv=none; d=zohomail.com; s=zohoarc; b=ZN8kSC37Uhivj8uYlML8v3qplQXWJQa2tk4SGuDbFUfCwtR/jIloi8PcL62L+UmBeN6ZU/kAMenv/g4kPCGC698isBhP0pKSd9Y2Nse+j3f+u2/p/ZQ7HIxl2T/EmMMklJC/blev2BPZ1dZ2VRNF/7K6xVZ21Z3tv8tfqClwAA0= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1578677910; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=5EL+5+x+Vj2DalU+m/ovKS7r5Wc7mPC5/7p6MkBt67I=; b=i6qQd6q+u2fMKYxqqLM5597SYyB8DZfTrJ49s307hoY8YCp24/LLWZO3cnyz8kRvARocM8gTHV3pJVBf/ryTFjptZYOgafPMp9E8LOzLFvv1iwDkpaxg0AcoevNz99o8z6rq0J2GiJqPeKx2/D0GJxuMTb8XP8CEjcvsjreax0U= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1578677910481867.4618975584156; Fri, 10 Jan 2020 09:38:30 -0800 (PST) Received: from localhost ([::1]:49842 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ipyEv-0001Zi-0a for importer@patchew.org; Fri, 10 Jan 2020 12:38:29 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:44075) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ipy9K-000331-9v for qemu-devel@nongnu.org; Fri, 10 Jan 2020 12:32:43 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ipy9J-00089n-3k for qemu-devel@nongnu.org; Fri, 10 Jan 2020 12:32:42 -0500 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:23158 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 1ipy9I-00087X-UG for qemu-devel@nongnu.org; Fri, 10 Jan 2020 12:32:41 -0500 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-13-taq-H4FaOo6isdBCQvLrbg-1; Fri, 10 Jan 2020 12:32:38 -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 E1E8B1B18BC0; Fri, 10 Jan 2020 17:32:36 +0000 (UTC) Received: from secure.mitica (ovpn-116-240.ams2.redhat.com [10.36.116.240]) by smtp.corp.redhat.com (Postfix) with ESMTP id 99EEF19C4F; Fri, 10 Jan 2020 17:32:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1578677560; 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=5EL+5+x+Vj2DalU+m/ovKS7r5Wc7mPC5/7p6MkBt67I=; b=QkmLDBeIuXcBPN3/6S4OjvWTGlXaOuPUC5CyDzmy33QL3ByWuMJXSqXIQU/3Lec4RsrWB6 wl0E31aUmdtivgpcW+8kFzp2tWtuPes1tQovpJjRxv3fxDn/DkZHtdvyTKK2ZN8yII0bi8 TRo5YejH29xtWttlrPU0oEmw3wShHZ0= From: Juan Quintela To: qemu-devel@nongnu.org Subject: [PULL 02/28] migration: Make sure that we don't call write() in case of error Date: Fri, 10 Jan 2020 18:31:49 +0100 Message-Id: <20200110173215.3865-3-quintela@redhat.com> In-Reply-To: <20200110173215.3865-1-quintela@redhat.com> References: <20200110173215.3865-1-quintela@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-MC-Unique: taq-H4FaOo6isdBCQvLrbg-1 X-Mimecast-Spam-Score: 0 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: 207.211.31.81 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 , Juan Quintela , Peter Maydell , Stefan Weil , Jason Wang , "Michael S. Tsirkin" , "Dr. David Alan Gilbert" , qemu-arm@nongnu.org, qemu-ppc@nongnu.org, David Gibson , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Paolo Bonzini , Stefan Berger , Richard Henderson Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" 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 96feb4062c..6e678dbd2e 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