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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 02969C433EF for ; Wed, 29 Sep 2021 08:45:53 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id ACA4C61357 for ; Wed, 29 Sep 2021 08:45:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org ACA4C61357 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 3C69C6B007B; Wed, 29 Sep 2021 04:45:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 376316B007D; Wed, 29 Sep 2021 04:45:52 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 23DCC940011; Wed, 29 Sep 2021 04:45:52 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0001.hostedemail.com [216.40.44.1]) by kanga.kvack.org (Postfix) with ESMTP id 12D326B007B for ; Wed, 29 Sep 2021 04:45:52 -0400 (EDT) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id B786718037C7D for ; Wed, 29 Sep 2021 08:45:51 +0000 (UTC) X-FDA: 78639978102.01.94FFBE2 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by imf29.hostedemail.com (Postfix) with ESMTP id 4D1719000247 for ; Wed, 29 Sep 2021 08:45:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1632905150; 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=Gvu4L83YOBGLGvWqLGUuGEaO/DEUZyEQ1rFR5bn6b8M=; b=dn4Yf3DSKpOnx6irOrP5sDy1RRXNbRYGwkRYj6I2BGdqeGdEbZLylbKNs8h/QJyxtcAiat 9HIifT19catRNnmqcUsVi6HLHyDFe2LPaIhLHe0NkoLR7xGzGCFLIB0MjukRfjR7lbBa43 tzRdLA/5i66ovys90FAvtN+tweYXpSg= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-319-RkSLoV1rOXCF2mbRtogn2Q-1; Wed, 29 Sep 2021 04:45:47 -0400 X-MC-Unique: RkSLoV1rOXCF2mbRtogn2Q-1 Received: by mail-wm1-f70.google.com with SMTP id l42-20020a05600c1d2a00b0030d02f09530so578779wms.0 for ; Wed, 29 Sep 2021 01:45:47 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:subject:to:cc:references:from:organization :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=Gvu4L83YOBGLGvWqLGUuGEaO/DEUZyEQ1rFR5bn6b8M=; b=A/h89stgkieP1nhJsfc8chlwOVPI8LAa4N+VShVhfZyiutDpm1jSXl8iNhOvLOy2RW hYt5NqMLiHmSWN6+9r+3KF4OJ7drwKspBFTnSERPvTUZ1Wkjg4Oey76abcOq0li+Y6EM LSK0DBwrp2yFtqxs5rd3SqQf3aDqPzMghnoKr/0Ka4BK/CeV5uQkrr3sIt0Spfb0i3DH d0AIyaEEpoVtAi0n5KgHIwpPLFoe0myvJ1Iwxy7Zsab5Na7aX5qe52ca/Qj6fhccQHy3 +aNPAaIZzsjMuBrP1dJ6ePtPCsNGrejnUueJm8wdqLLCXbqZKJHH9eGEdg0P++LLPyD3 AiDQ== X-Gm-Message-State: AOAM532e6F9SzwIHxj7u7a9jhvgy65HL1Rr/qiDCCMNpnnThb0lpndhs yI1bdAlgu2xFERR1CjMBmu0j8Vbd+2dV3v2QU4QxGpI2htGtFr9B89Nl7P2KwNfKo1DuV13XBzK PtCVFLRiH8t/po31b0dDMTS4NWJjXQ5h3u239GjzU8ot5P0zMbsAXI9NOMnE= X-Received: by 2002:a1c:7c0f:: with SMTP id x15mr8734524wmc.149.1632905146313; Wed, 29 Sep 2021 01:45:46 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyaikWIkzzrJGqHValULa/ZmnNfg4rl1LyjKqzMWVt+gz9mbskxaXhni5v3m042+vSd753h3g== X-Received: by 2002:a1c:7c0f:: with SMTP id x15mr8734485wmc.149.1632905146123; Wed, 29 Sep 2021 01:45:46 -0700 (PDT) Received: from [192.168.3.132] (p4ff23c3b.dip0.t-ipconnect.de. [79.242.60.59]) by smtp.gmail.com with ESMTPSA id t126sm893773wma.4.2021.09.29.01.45.44 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 29 Sep 2021 01:45:45 -0700 (PDT) Subject: Re: [PATCH v1 2/8] x86/xen: simplify xen_oldmem_pfn_is_ram() To: Boris Ostrovsky , linux-kernel@vger.kernel.org Cc: Andrew Morton , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Juergen Gross , Stefano Stabellini , "Michael S. Tsirkin" , Jason Wang , Dave Young , Baoquan He , Vivek Goyal , Michal Hocko , Oscar Salvador , Mike Rapoport , "Rafael J. Wysocki" , x86@kernel.org, xen-devel@lists.xenproject.org, virtualization@lists.linux-foundation.org, kexec@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org References: <20210928182258.12451-1-david@redhat.com> <20210928182258.12451-3-david@redhat.com> <4ab2f8c2-c3d5-30b3-a670-a8b38e218b6e@oracle.com> From: David Hildenbrand Organization: Red Hat Message-ID: Date: Wed, 29 Sep 2021 10:45:44 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <4ab2f8c2-c3d5-30b3-a670-a8b38e218b6e@oracle.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 4D1719000247 X-Stat-Signature: w7kf6n4mt99oro5wsz4ncz9ae7h9bhoa Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=dn4Yf3DS; dmarc=pass (policy=none) header.from=redhat.com; spf=none (imf29.hostedemail.com: domain of david@redhat.com has no SPF policy when checking 216.205.24.124) smtp.mailfrom=david@redhat.com X-HE-Tag: 1632905151-232918 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: >=20 > How about >=20 > =C2=A0=C2=A0=C2=A0 return a.mem_type !=3D HVMMEM_mmio_dm; >=20 Ha, how could I have missed that :) >=20 > Result should be promoted to int and this has added benefit of not requ= iring changes in patch 4. >=20 Can we go one step further and do @@ -20,24 +20,11 @@ static int xen_oldmem_pfn_is_ram(unsigned long pfn) struct xen_hvm_get_mem_type a =3D { .domid =3D DOMID_SELF, .pfn =3D pfn, + .mem_type =3D HVMMEM_ram_rw, }; - int ram; =20 - if (HYPERVISOR_hvm_op(HVMOP_get_mem_type, &a)) - return -ENXIO; - - switch (a.mem_type) { - case HVMMEM_mmio_dm: - ram =3D 0; - break; - case HVMMEM_ram_rw: - case HVMMEM_ram_ro: - default: - ram =3D 1; - break; - } - - return ram; + HYPERVISOR_hvm_op(HVMOP_get_mem_type, &a); + return a.mem_type !=3D HVMMEM_mmio_dm; } #endif Assuming that if HYPERVISOR_hvm_op() fails that .mem_type is not set to HVMMEM_mmio_dm. --=20 Thanks, David / dhildenb