From patchwork Wed Dec 18 05:04:39 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Juan Quintela X-Patchwork-Id: 11299525 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EFE1A138C for ; Wed, 18 Dec 2019 05:06:05 +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 BD6FA21582 for ; Wed, 18 Dec 2019 05:06:05 +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="H8Tzm32E" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BD6FA21582 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+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:49722 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ihRXA-0008DK-Cn for patchwork-qemu-devel@patchwork.kernel.org; Wed, 18 Dec 2019 00:06:04 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:48273) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ihRW1-0006va-U1 for qemu-devel@nongnu.org; Wed, 18 Dec 2019 00:04:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ihRW0-0003kf-J1 for qemu-devel@nongnu.org; Wed, 18 Dec 2019 00:04:53 -0500 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:40637 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 1ihRW0-0003iX-Dc for qemu-devel@nongnu.org; Wed, 18 Dec 2019 00:04:52 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1576645492; 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=Z85wuO3YWoeRNkarji+P9H3WlDB4HRutxh9nmFLYEyg=; b=H8Tzm32EjQAhMm8DmUmN2WY53oTJWO2pNUYLfcN2ozOb4Lt21+4Xs2SCVK64+rLcJRxymv MXMhMkBJxottsmsQG+wYduDujh9qOpUk7o82ml/yfpjVD+yCj/zGeFF1ByVofUA3mDZegk s+mgKATHDstE+TnhtWwacgnzUgNXSZ8= 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-106-wfe4FHTcMhGO5yL3xBBwyQ-1; Wed, 18 Dec 2019 00:04:50 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id DE15791252 for ; Wed, 18 Dec 2019 05:04:49 +0000 (UTC) Received: from secure.mitica (ovpn-116-32.ams2.redhat.com [10.36.116.32]) by smtp.corp.redhat.com (Postfix) with ESMTP id 64DE75D9E1; Wed, 18 Dec 2019 05:04:48 +0000 (UTC) From: Juan Quintela To: qemu-devel@nongnu.org Subject: [PATCH 4/4] migration: Make sure that we don't call write() in case of error Date: Wed, 18 Dec 2019 06:04:39 +0100 Message-Id: <20191218050439.5989-5-quintela@redhat.com> In-Reply-To: <20191218050439.5989-1-quintela@redhat.com> References: <20191218050439.5989-1-quintela@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-MC-Unique: wfe4FHTcMhGO5yL3xBBwyQ-1 X-Mimecast-Spam-Score: 0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 205.139.110.120 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 , Paolo Bonzini , Thomas Huth , "Dr. David Alan Gilbert" , Juan Quintela Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.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 | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/migration/ram.c b/migration/ram.c index 4b44578e57..909ef6d237 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1601,6 +1601,12 @@ struct { QemuSemaphore channels_ready; /* multifd ops */ MultiFDMethods *ops; + /* + * 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; /* @@ -1629,6 +1635,10 @@ static int multifd_send_pages(RAMState *rs) MultiFDPages_t *pages = multifd_send_state->pages; uint64_t transferred; + if (atomic_read(&multifd_send_state->exiting)) { + return -1; + } + qemu_sem_wait(&multifd_send_state->channels_ready); for (i = next_channel;; i = (i + 1) % migrate_multifd_channels()) { p = &multifd_send_state->params[i]; @@ -1710,6 +1720,10 @@ static void multifd_send_terminate_threads(Error *err) } } + if (atomic_xchg(&multifd_send_state->exiting, 1)) { + return; + } + for (i = 0; i < migrate_multifd_channels(); i++) { MultiFDSendParams *p = &multifd_send_state->params[i]; @@ -1824,6 +1838,10 @@ static void *multifd_send_thread(void *opaque) while (true) { qemu_sem_wait(&p->sem); + + if (atomic_read(&multifd_send_state->exiting)) { + break; + } qemu_mutex_lock(&p->mutex); if (p->pending_job) { @@ -1938,6 +1956,7 @@ int multifd_save_setup(Error **errp) multifd_send_state->pages = multifd_pages_init(page_count); qemu_sem_init(&multifd_send_state->channels_ready, 0); multifd_send_state->ops = multifd_ops[migrate_multifd_method()]; + atomic_set(&multifd_send_state->exiting, 0); for (i = 0; i < thread_count; i++) { MultiFDSendParams *p = &multifd_send_state->params[i];