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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 5DADEC4167B for ; Mon, 19 Dec 2022 16:24:03 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1p7IvB-0000ay-7D; Mon, 19 Dec 2022 11:23:21 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p7Iv9-0000a4-NP for qemu-devel@nongnu.org; Mon, 19 Dec 2022 11:23:19 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p7Iv7-0006tU-OA for qemu-devel@nongnu.org; Mon, 19 Dec 2022 11:23:19 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1671466995; 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=yquUcng3A002kNONt0VbVz69nwYvoU++xz32gs6N2YE=; b=C46N1vkYONK4vPf5kei6oB6PULIDHybbnI/T2eKtQeOCrvIl6PoVbbN5C3Hq62G9jv5ca3 g6O9MIcD9RqHrVCzLWn5eQRx9WG4rBl2ARoebErp/b0HUNTHj+I+L9V7oRRYE/GsoZskhW kFak9BQlcq495pERqlAxHtOajYBgqgI= Received: from mail-qt1-f197.google.com (mail-qt1-f197.google.com [209.85.160.197]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-609-cABGzDxSNTeMPqeyJqEpEA-1; Mon, 19 Dec 2022 11:23:14 -0500 X-MC-Unique: cABGzDxSNTeMPqeyJqEpEA-1 Received: by mail-qt1-f197.google.com with SMTP id h26-20020ac8505a000000b003a7e8e8b03bso4184434qtm.18 for ; Mon, 19 Dec 2022 08:23:14 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=yquUcng3A002kNONt0VbVz69nwYvoU++xz32gs6N2YE=; b=Cb+a3WDpyZ/amiOx2hRbWDNVAkTegjtHJAFa+LulAp2eZ7tZq3jkkxZLDh5ikzD4ax WmGBpPnfouFfII6nFD2ClITaW6Cge6UJSWlcPLTzVMT+pHk33gqXPwsBXmHt80cRWVv8 lvCvsDvHXrC/hkeBHRM6ijUjOEVJLvYMK02orU41rTYn62bN0rmMamCZE4wK3LwtNNEH CM8LEjosHX47z5sVLPi1/L214kafiqQhSHUgU3FPWyL8iekU8pbqgaun9Aa2VzOlX0d0 ovQmbXdqrj1kVVsN1hrC+K0X0Z3ua6twSBlgFs3GEvm/KvZJBa2sFMF2dQ0stX6vrbD4 obTw== X-Gm-Message-State: ANoB5pmvdQn37H/y6KVbLWKTWPwuCHb0pgl25a+IG3RwlXpjZNro6JUY nGRchKpmVGn6mr0pihk2VBPA+MQl1/SFSRdoUgvIcZ2Lw93HTvNWErYUqsXwcEDtAru+ybyCj50 L66555PKd/faUNTs= X-Received: by 2002:a05:622a:6114:b0:3a7:fd82:f69b with SMTP id hg20-20020a05622a611400b003a7fd82f69bmr47740695qtb.8.1671466993638; Mon, 19 Dec 2022 08:23:13 -0800 (PST) X-Google-Smtp-Source: AA0mqf6Y2qXzcA4DZZkshxgVOYiF728sVZhnpCCgaeTFr8ChBfqjOTeyokRTSMmdtNg+VXZcVKyyEg== X-Received: by 2002:a05:622a:6114:b0:3a7:fd82:f69b with SMTP id hg20-20020a05622a611400b003a7fd82f69bmr47740674qtb.8.1671466993353; Mon, 19 Dec 2022 08:23:13 -0800 (PST) Received: from redhat.com ([45.144.113.29]) by smtp.gmail.com with ESMTPSA id b24-20020ac844d8000000b0035badb499c7sm6184812qto.21.2022.12.19.08.23.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 Dec 2022 08:23:12 -0800 (PST) Date: Mon, 19 Dec 2022 11:23:08 -0500 From: "Michael S. Tsirkin" To: Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= Cc: Paolo Bonzini , QEMU Developers Subject: Re: Should -overcommit cpu-pm=on|off be converted to some machine sugar property? Message-ID: <20221219112210-mutt-send-email-mst@kernel.org> References: <3ce8e739-4894-b79e-1972-f972fd763e5b@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <3ce8e739-4894-b79e-1972-f972fd763e5b@linaro.org> Received-SPF: pass client-ip=170.10.129.124; envelope-from=mst@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, 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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Mon, Dec 19, 2022 at 05:11:11PM +0100, Philippe Mathieu-Daudé wrote: > Hi Paolo, > > I just noticed 'enable_cpu_pm' which seems architecture specific > option that ended into common code: > > $ git grep -E 'cpu[_-]pm' > accel/tcg/user-exec-stub.c:5:bool enable_cpu_pm = false; > include/sysemu/sysemu.h:49:extern bool enable_cpu_pm; > Binary file pc-bios/skiboot.lid matches > qemu-options.hx:4196: "-overcommit [mem-lock=on|off][cpu-pm=on|off]\n" > qemu-options.hx:4199: " cpu-pm=on|off controls cpu power > management (default: off)\n", > qemu-options.hx:4204:``-overcommit cpu-pm=on|off`` > qemu-options.hx:4214: guest) can be enabled via ``cpu-pm=on`` (disabled > by default). This > softmmu/globals.c:38:bool enable_cpu_pm; > softmmu/vl.c:350: .name = "cpu-pm", > softmmu/vl.c:3440: enable_cpu_pm = qemu_opt_get_bool(opts, > "cpu-pm", false); > target/i386/host-cpu.c:44:static void host_cpu_enable_cpu_pm(X86CPU *cpu) > target/i386/host-cpu.c:88: if (cpu->max_features && enable_cpu_pm) { > target/i386/host-cpu.c:89: host_cpu_enable_cpu_pm(cpu); > target/i386/kvm/kvm-cpu.c:43: if (enable_cpu_pm && kvm_has_waitpkg()) > { > target/i386/kvm/kvm.c:390: if (enable_cpu_pm) { > target/i386/kvm/kvm.c:2576: if (enable_cpu_pm) { > > Do we want to maintain this as a generic property or > can it be deprecated / converted to a machine-specific one? > > Thanks, > > Phil. I don't care much. ATM it only works well if you have a dedicated host CPU and memory, this is why we put it in -overcommit. -- MST