From patchwork Wed Feb 1 09:13:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Baoquan He X-Patchwork-Id: 51245 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:adf:eb09:0:0:0:0:0 with SMTP id s9csp173546wrn; Wed, 1 Feb 2023 01:29:54 -0800 (PST) X-Google-Smtp-Source: AK7set+H05nrThHkte4fIZMokBn+O2BOplEXffzJlItLUwIcXcu4AfYoZtYjcWG/hduPfWJSBGPQ X-Received: by 2002:a17:906:5054:b0:889:d156:616d with SMTP id e20-20020a170906505400b00889d156616dmr1611018ejk.27.1675243794602; Wed, 01 Feb 2023 01:29:54 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1675243794; cv=none; d=google.com; s=arc-20160816; b=htzd4o5maXgRAj2rH1w8aiCgVFmUvdDzJpv4HmcW6ERMIZd1vQ4DQBkzMAZk8hid+l rLDWhkwcXl5JncYlFl/gDUKrNL+UV6XVJWquxPAK67Zbmv5jJW0evkfrSD4jOAaWd+I5 yJjHKFMoTKl9RumZBBXbAGapoCbKdrDsMABpq6XYHCBwA69fZocXkRlL06MjgTbs7vhf ekMJ2YJ6r4ptzXxhxAjpcJUhLF9zfj6si7QwtGurp5BGz6Tplbh/83Iz9IyXR3bkKuk/ jZQVtJBe8xR9IooM0xvVGqMhW0ey1bji35bK766e0hv4dexsYf/LTVUzOyljW48cZuda f14w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=5ERwgOoTIt99ygprY7f+Kv4bRDSO29pRQMOJk0egizU=; b=al4dCSqbGezQP48ZFiqxKbJgILspQLF5castZvH72gUn4kSAQBsULHfecAVFgbD7sz 48D/D+T3ffQwbPXOhShtNNgdm6LpEvTZNP2W7LraHB633LGWgxdX8ZaC531lHA+bFIda KcL9Z+i1q8mJ8M5WFhTQ2HbhLCwkZ7XU00SLnRpvOdh1Z+nsidZtXZppBu09+n1BoJ82 gRT4PKUo8drk8ADcVvTbvpb/A9/qQumg58PfEajmXCHXuLaV0rhAVmKDH+MZNoaJm2we TQN2e+o6Q22yVirf+IWNgnrLYnQSndflMyx26g7zTFab+ZWT+pTo+hxCb33ovlLAGKPI KIWQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=H2qzEb17; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id az6-20020a170907904600b0084d43e4541csi20320099ejc.720.2023.02.01.01.29.31; Wed, 01 Feb 2023 01:29:54 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=H2qzEb17; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232014AbjBAJPZ (ORCPT + 99 others); Wed, 1 Feb 2023 04:15:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39680 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232069AbjBAJPC (ORCPT ); Wed, 1 Feb 2023 04:15:02 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 124CC3802F for ; Wed, 1 Feb 2023 01:14:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1675242856; 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=5ERwgOoTIt99ygprY7f+Kv4bRDSO29pRQMOJk0egizU=; b=H2qzEb172qQVqeSluxsVwdy0HMOIIZZvc101dj/J8yDw1OlnWkED8nkNk2k5waAbbp/pmG Xz94moQalib+pFbJTOWDZPF/84MJoEaPmk+NmvU7a207KBzk1GpLBPeqziW+6D3eweLHOP DQfEY4umszD3pF4y/ApnQvarUa8PFuM= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-195-Lifv6lTfO0SmDChZSfFdLA-1; Wed, 01 Feb 2023 04:14:13 -0500 X-MC-Unique: Lifv6lTfO0SmDChZSfFdLA-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 833AD183B3C0; Wed, 1 Feb 2023 09:14:12 +0000 (UTC) Received: from MiWiFi-R3L-srv.redhat.com (ovpn-13-89.pek2.redhat.com [10.72.13.89]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0F5BF492C3E; Wed, 1 Feb 2023 09:14:07 +0000 (UTC) From: Baoquan He To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, akpm@linux-foundation.org, stephen.s.brennan@oracle.com, urezki@gmail.com, lstoakes@gmail.com, willy@infradead.org, hch@infradead.org, error27@gmail.com, Baoquan He Subject: [PATCH v4 5/7] mm/vmalloc: skip the uninitilized vmalloc areas Date: Wed, 1 Feb 2023 17:13:37 +0800 Message-Id: <20230201091339.61761-6-bhe@redhat.com> In-Reply-To: <20230201091339.61761-1-bhe@redhat.com> References: <20230201091339.61761-1-bhe@redhat.com> MIME-Version: 1.0 Content-type: text/plain X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1756620437118933715?= X-GMAIL-MSGID: =?utf-8?q?1756620437118933715?= For areas allocated via vmalloc_xxx() APIs, it searches for unmapped area to reserve and allocates new pages to map into, please see function __vmalloc_node_range(). During the process, flag VM_UNINITIALIZED is set in vm->flags to indicate that the pages allocation and mapping haven't been done, until clear_vm_uninitialized_flag() is called to clear VM_UNINITIALIZED. For this kind of area, if VM_UNINITIALIZED is still set, let's ignore it in vread() because pages newly allocated and being mapped in that area only contains zero data. reading them out by aligned_vread() is wasting time. Signed-off-by: Baoquan He Reviewed-by: Lorenzo Stoakes Reviewed-by: Uladzislau Rezki (Sony) --- mm/vmalloc.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index e515dbacb0cb..504b63606613 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -3667,6 +3667,11 @@ long vread(char *buf, char *addr, unsigned long count) if (!vm && !flags) continue; + if (vm && (vm->flags & VM_UNINITIALIZED)) + continue; + /* Pair with smp_wmb() in clear_vm_uninitialized_flag() */ + smp_rmb(); + vaddr = (char *) va->va_start; size = vm ? get_vm_area_size(vm) : va_size(va);