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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 6B554C2B9F4 for ; Wed, 23 Jun 2021 00:34:31 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2467761358 for ; Wed, 23 Jun 2021 00:34:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2467761358 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 21E5C6B0074; Tue, 22 Jun 2021 20:34:30 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1CFDA6B0075; Tue, 22 Jun 2021 20:34:30 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0486B6B0078; Tue, 22 Jun 2021 20:34:29 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0158.hostedemail.com [216.40.44.158]) by kanga.kvack.org (Postfix) with ESMTP id BBE056B0074 for ; Tue, 22 Jun 2021 20:34:29 -0400 (EDT) Received: from smtpin39.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id E8212181C9912 for ; Wed, 23 Jun 2021 00:34:29 +0000 (UTC) X-FDA: 78283117458.39.73B412F Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by imf25.hostedemail.com (Postfix) with ESMTP id A00E5600054E for ; Wed, 23 Jun 2021 00:34:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1624408469; 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=5DD3r7S7GR9o4bUbRoCZsNEGAJhl3XhPziKFFHvGYoY=; b=iilowhXLudLUR0/SaxO0RCjpOOyv5rrBn4Xs7ky9TyB/9dInAy/ynNCleoYV44DjZwSIbQ K6TapYtJrqhc/WGn/WExyIy+wL/SYWVN837OjarfHFIJlzRrrELlsNFPER18MWw4Gt89E0 t7e5uVT65lcJkboSTxu6f3x39AC7r1Y= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-5--LanzLepO7WzhPemGkLm6Q-1; Tue, 22 Jun 2021 20:34:28 -0400 X-MC-Unique: -LanzLepO7WzhPemGkLm6Q-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 74F81800C60; Wed, 23 Jun 2021 00:34:26 +0000 (UTC) Received: from gshan.redhat.com (vpn2-54-84.bne.redhat.com [10.64.54.84]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2F9F610023AB; Wed, 23 Jun 2021 00:34:16 +0000 (UTC) From: Gavin Shan To: linux-mm@kvack.org Cc: alexander.duyck@gmail.com, david@redhat.com, mst@redhat.com, akpm@linux-foundation.org, anshuman.khandual@arm.com, catalin.marinas@arm.com, will@kernel.org, shan.gavin@gmail.com Subject: [PATCH v3 3/4] mm/page_reporting: Allow driver to specify reporting order Date: Wed, 23 Jun 2021 10:34:17 +0800 Message-Id: <20210623023418.350616-4-gshan@redhat.com> In-Reply-To: <20210623023418.350616-1-gshan@redhat.com> References: <20210623023418.350616-1-gshan@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=UTF-8 Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=iilowhXL; spf=none (imf25.hostedemail.com: domain of gshan@redhat.com has no SPF policy when checking 216.205.24.124) smtp.mailfrom=gshan@redhat.com; dmarc=pass (policy=none) header.from=redhat.com X-Stat-Signature: hpzoreqfm35qzh74euqgmyjcatb8ja9b X-Rspamd-Queue-Id: A00E5600054E X-Rspamd-Server: rspam06 X-HE-Tag: 1624408469-241830 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: The page reporting order (threshold) is sticky to @pageblock_order by default. The page reporting can never be triggered because the freeing page can't come up with a free area like that huge. The situation becomes worse when the system memory becomes heavily fragmented. For example, the following configurations are used on ARM64 when 64KB base page size is enabled. In this specific case, the page reporting won't be triggered until the freeing page comes up with a 512MB free area. That's hard to be met, especially when the system memory becomes heavily fragmented. PAGE_SIZE: 64KB HPAGE_SIZE: 512MB pageblock_order: 13 (512MB) MAX_ORDER: 14 This allows the drivers to specify the page reporting order when the page reporting device is registered. It falls back to @pageblock_order if it's not specified by the driver. The existing users (hv_balloon and virtio_balloon) don't specify it and @pageblock_order is still taken as their page reporting order. So this shouldn't introduce any functional changes. Signed-off-by: Gavin Shan --- include/linux/page_reporting.h | 3 +++ mm/page_reporting.c | 4 ++++ 2 files changed, 7 insertions(+) diff --git a/include/linux/page_reporting.h b/include/linux/page_reportin= g.h index 3b99e0ec24f2..fe648dfa3a7c 100644 --- a/include/linux/page_reporting.h +++ b/include/linux/page_reporting.h @@ -18,6 +18,9 @@ struct page_reporting_dev_info { =20 /* Current state of page reporting */ atomic_t state; + + /* Minimal order of page reporting */ + unsigned int order; }; =20 /* Tear-down and bring-up for page reporting devices */ diff --git a/mm/page_reporting.c b/mm/page_reporting.c index 293a8713ef7c..7c0c811948a7 100644 --- a/mm/page_reporting.c +++ b/mm/page_reporting.c @@ -328,6 +328,10 @@ int page_reporting_register(struct page_reporting_de= v_info *prdev) goto err_out; } =20 + /* Use the page reporting order if it's specified by driver */ + page_reporting_order =3D prdev->order ? + prdev->order : page_reporting_order; + /* initialize state and work structures */ atomic_set(&prdev->state, PAGE_REPORTING_IDLE); INIT_DELAYED_WORK(&prdev->work, &page_reporting_process); --=20 2.23.0