From patchwork Mon Feb 4 18:19:49 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander H Duyck X-Patchwork-Id: 10796337 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E4DC017FB for ; Mon, 4 Feb 2019 18:19:57 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D7253283A2 for ; Mon, 4 Feb 2019 18:19:57 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CB30E2B94E; Mon, 4 Feb 2019 18:19:57 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7FF18283A2 for ; Mon, 4 Feb 2019 18:19:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728482AbfBDSTv (ORCPT ); Mon, 4 Feb 2019 13:19:51 -0500 Received: from mail-pf1-f195.google.com ([209.85.210.195]:46815 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726585AbfBDSTv (ORCPT ); Mon, 4 Feb 2019 13:19:51 -0500 Received: by mail-pf1-f195.google.com with SMTP id c73so277365pfe.13; Mon, 04 Feb 2019 10:19:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:from:to:cc:date:message-id:in-reply-to:references :user-agent:mime-version:content-transfer-encoding; bh=Y7C467UHY1ApxkxNkde5pS9++k5K00rvSuCeNYW/XeQ=; b=iwdoEbbnl4vZrbishwBQADfm0EjzsEvtHQeQ6GN0r++6qhZmzJ4ra5tLQ/peaafWbw GVn04HzCjogTvmqOQVez+ktoUNo643bJP+Voe3yD2BNf9GGKcUiuhld+hFM99JLyyuTy Yfz+Ft0DJiABsRnpy8YvYeISWquaVnSpYfsfr9te6EaUtjikDvw7UUfjGd56lzJLLwUf UV2OAV5ORXguYBBzpKG2kFVB0EB0xq4Vf7tQTZmqIoFZypIHOX1vmeJh7cCZkmMmUx3j UsBBFie+qczkJY7HzLQgkDB6dyJPnGBJ9UsDEHwX3DIS1/Cw/wbIEYGaAxVDoqrkJw9V wlWw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:cc:date:message-id:in-reply-to :references:user-agent:mime-version:content-transfer-encoding; bh=Y7C467UHY1ApxkxNkde5pS9++k5K00rvSuCeNYW/XeQ=; b=EzsduwiSDpt6cBLC9Qv2OpE9B3DOHgxnCrRd82Z5bLs2YZsVhkOh4KPhAxNcA7xk9v Ku8szrk7keEYiFUZYFlEopByiTSNOhRbBKTktngZNlGRhL1igbmZv7SdCZQ43zuXdlkP vblozJq1y+c3QvrA6jDPy/5ZJMgQuvnDZXxiuK/XJbDDKNE1v8ypbMzW9YQbI0/T/HQm CaFgEOn4i6P9XVCWlHJah7mpYxEKiBgNeyt2/ZVt/L68Y3QmvFKNQyGpFZkFrNzGw6ZA eGU84w3JYanoAd2vRhCI0p2EB3HU6BJmXUOyXes4d7idkatcwqu6HOrae4X1JYP5Mh1c zcIA== X-Gm-Message-State: AHQUAuYgqmLQaXYVU52PBOTWdc3c2yisKeegi2EYuBeP7m7OdSotBL/I ZVl1qYBe62ICwE19ioZ6k4k= X-Google-Smtp-Source: AHgI3IaZ5KYOLTDHY5ylXp1cXQI1eFxJVc/+W8nm45glPPlIfvBa3WiT3NNRTVLf89Oqk2rOV4wjQQ== X-Received: by 2002:a63:3206:: with SMTP id y6mr627427pgy.338.1549304390629; Mon, 04 Feb 2019 10:19:50 -0800 (PST) Received: from localhost.localdomain ([2001:470:b:9c3:9e5c:8eff:fe4f:f2d0]) by smtp.gmail.com with ESMTPSA id d21sm811265pgv.37.2019.02.04.10.19.49 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 04 Feb 2019 10:19:50 -0800 (PST) Subject: [RFC PATCH QEMU] i386/kvm: Enable paravirtual unused page hint mechanism From: Alexander Duyck To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: rkrcmar@redhat.com, alexander.h.duyck@linux.intel.com, x86@kernel.org, mingo@redhat.com, bp@alien8.de, hpa@zytor.com, pbonzini@redhat.com, tglx@linutronix.de, akpm@linux-foundation.org Date: Mon, 04 Feb 2019 10:19:49 -0800 Message-ID: <20190204181825.12252.81443.stgit@localhost.localdomain> In-Reply-To: <20190204181118.12095.38300.stgit@localhost.localdomain> References: <20190204181118.12095.38300.stgit@localhost.localdomain> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Alexander Duyck This patch adds the flag named kvm-pv-unused-page-hint. This functionality is enabled by kvm for x86 and provides a mechanism by which the guest can indicate to the host which pages it is no longer using. By providing these hints the guest can help to reduce the memory pressure on the host as dirtied pages will be cleared and not written out to swap if they are marked as being unused. Signed-off-by: Alexander Duyck --- target/i386/cpu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/target/i386/cpu.c b/target/i386/cpu.c index 2f5412592d30..0d19a9dc64f1 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -900,7 +900,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = { "kvmclock", "kvm-nopiodelay", "kvm-mmu", "kvmclock", "kvm-asyncpf", "kvm-steal-time", "kvm-pv-eoi", "kvm-pv-unhalt", NULL, "kvm-pv-tlb-flush", NULL, "kvm-pv-ipi", - NULL, NULL, NULL, NULL, + "kvm-pv-unused-page-hint", NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, "kvmclock-stable-bit", NULL, NULL, NULL,