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=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 E86F2C433DF for ; Wed, 5 Aug 2020 08:51:14 +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 C37AB2177B for ; Wed, 5 Aug 2020 08:51:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C37AB2177B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:46982 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k3F8k-0003rQ-1U for qemu-devel@archiver.kernel.org; Wed, 05 Aug 2020 04:51:14 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:51362) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k3F7v-0002oR-FP for qemu-devel@nongnu.org; Wed, 05 Aug 2020 04:50:23 -0400 Received: from mx2.suse.de ([195.135.220.15]:43794) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k3F7t-0000La-TU for qemu-devel@nongnu.org; Wed, 05 Aug 2020 04:50:23 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 2D966AC12; Wed, 5 Aug 2020 08:50:37 +0000 (UTC) Subject: Re: [RFC v3 2/8] cpus: prepare new CpusAccel cpu accelerator interface To: Paolo Bonzini , =?UTF-8?Q?Alex_Benn=c3=a9e?= , Peter Maydell , =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= References: <20200803090533.7410-1-cfontana@suse.de> <20200803090533.7410-3-cfontana@suse.de> <5594481c-e887-e48e-630b-c9ebbe542212@redhat.com> From: Claudio Fontana Message-ID: <92648e68-b2ac-83a5-40de-16f48fb2a28c@suse.de> Date: Wed, 5 Aug 2020 10:50:19 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <5594481c-e887-e48e-630b-c9ebbe542212@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=195.135.220.15; envelope-from=cfontana@suse.de; helo=mx2.suse.de X-detected-operating-system: by eggs.gnu.org: First seen = 2020/08/05 00:43:27 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x (no timestamps) [generic] X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action 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 , Thomas Huth , Eduardo Habkost , Marcelo Tosatti , qemu-devel@nongnu.org, Markus Armbruster , Roman Bolshakov , Pavel Dovgalyuk , Wenchao Wang , haxm-team@intel.com, Sunil Muthuswamy , Richard Henderson , Colin Xu Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 8/5/20 10:47 AM, Paolo Bonzini wrote: > On 05/08/20 10:40, Claudio Fontana wrote: >>> #ifdef _WIN32 >>> - /* Eat dummy APC queued by qemu_cpu_kick_thread. */ >>> + /* Eat dummy APC queued by qemu_cpu_kick_thread. */ >>> + /* NB!!! Should not this be if (hax_enabled)? Is this wrong for whpx? */ >>> if (!tcg_enabled()) { >>> SleepEx(0, TRUE); >>> } >> >> Looking at the history here, I think this should be if (hax_enabled()); >> this check was added at a time when whpx did not exist, so I _think_ there might have been an assumption here >> that !tcg_enabled() on windows means actually hax_enabled() for eating this dummy APC. > > Yes, that matches the condition under which QueueUserAPC is called in > qemu_cpu_kick_thread. > > Paolo > >> Probably it does not cause problems, because whpx does not end up calling qemu_wait_io_event, >> instead it calls qemu_wait_io_event_common. But it would be more expressive to use if (hax_enabled()) I think. > Thanks for the clarification, indeed, I'd then convert it to hax_enabled() in the series then, because this allows removing an extra include in cpus.c (no need to check for tcg_enabled() in cpus.c anymore)... thanks, Claudio