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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 A6C04C32789 for ; Tue, 6 Nov 2018 21:05:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 74BC520862 for ; Tue, 6 Nov 2018 21:05:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 74BC520862 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388708AbeKGGcV (ORCPT ); Wed, 7 Nov 2018 01:32:21 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:52326 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726671AbeKGGcV (ORCPT ); Wed, 7 Nov 2018 01:32:21 -0500 Received: from akpm3.svl.corp.google.com (unknown [104.133.8.65]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 9F3009E7; Tue, 6 Nov 2018 21:05:12 +0000 (UTC) Date: Tue, 6 Nov 2018 13:05:11 -0800 From: Andrew Morton To: Rick Edgecombe Cc: jeyu@kernel.org, willy@infradead.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, kernel-hardening@lists.openwall.com, daniel@iogearbox.net, jannh@google.com, keescook@chromium.org, kristen@linux.intel.com, dave.hansen@intel.com, arjan@linux.intel.com Subject: Re: [PATCH v8 1/4] vmalloc: Add __vmalloc_node_try_addr function Message-Id: <20181106130511.9ebeb5a09aba15dfee2f7f3d@linux-foundation.org> In-Reply-To: <20181102192520.4522-2-rick.p.edgecombe@intel.com> References: <20181102192520.4522-1-rick.p.edgecombe@intel.com> <20181102192520.4522-2-rick.p.edgecombe@intel.com> X-Mailer: Sylpheed 3.6.0 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2 Nov 2018 12:25:17 -0700 Rick Edgecombe wrote: > Create __vmalloc_node_try_addr function that tries to allocate at a specific > address without triggering any lazy purging. In order to support this behavior > a try_addr argument was plugged into several of the static helpers. Please explain (in the changelog) why lazy purging is considered to be a problem. Preferably with some form of measurements, or at least a hand-wavy guesstimate of the cost. > This also changes logic in __get_vm_area_node to be faster in cases where > allocations fail due to no space, which is a lot more common when trying > specific addresses.