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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 09900C76186 for ; Wed, 17 Jul 2019 11:21:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E3E452173E for ; Wed, 17 Jul 2019 11:20:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726580AbfGQLUz (ORCPT ); Wed, 17 Jul 2019 07:20:55 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54500 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725799AbfGQLUz (ORCPT ); Wed, 17 Jul 2019 07:20:55 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5B1D33082133; Wed, 17 Jul 2019 11:20:55 +0000 (UTC) Received: from redhat.com (ovpn-120-247.rdu2.redhat.com [10.10.120.247]) by smtp.corp.redhat.com (Postfix) with SMTP id EB7D55C232; Wed, 17 Jul 2019 11:20:34 +0000 (UTC) Date: Wed, 17 Jul 2019 07:20:33 -0400 From: "Michael S. Tsirkin" To: Alexander Duyck Cc: wei.w.wang@intel.com, Nitesh Narayan Lal , kvm list , David Hildenbrand , Dave Hansen , LKML , linux-mm , Andrew Morton , Yang Zhang , pagupta@redhat.com, Rik van Riel , Konrad Rzeszutek Wilk , lcapitulino@redhat.com, Andrea Arcangeli , Paolo Bonzini , dan.j.williams@intel.com, Alexander Duyck Subject: use of shrinker in virtio balloon free page hinting Message-ID: <20190717071332-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.42]); Wed, 17 Jul 2019 11:20:55 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Wei, others, ATM virtio_balloon_shrinker_scan will only get registered when deflate on oom feature bit is set. Not sure whether that's intentional. Assuming it is: virtio_balloon_shrinker_scan will try to locate and free pages that are processed by host. The above seems broken in several ways: - count ignores the free page list completely - if free pages are being reported, pages freed by shrinker will just get re-allocated again I was unable to make this part of code behave in any reasonable way - was shrinker usage tested? What's a good way to test that? Thanks! -- MST