From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752790AbZBTB2B (ORCPT ); Thu, 19 Feb 2009 20:28:01 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754344AbZBTB1w (ORCPT ); Thu, 19 Feb 2009 20:27:52 -0500 Received: from hera.kernel.org ([140.211.167.34]:45818 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752869AbZBTB1v (ORCPT ); Thu, 19 Feb 2009 20:27:51 -0500 Message-ID: <499E070E.3090304@kernel.org> Date: Fri, 20 Feb 2009 10:27:42 +0900 From: Tejun Heo User-Agent: Thunderbird 2.0.0.19 (X11/20081227) MIME-Version: 1.0 To: Nick Piggin CC: rusty@rustcorp.com.au, tglx@linutronix.de, x86@kernel.org, linux-kernel@vger.kernel.org, hpa@zytor.com, jeremy@goop.org, cpw@sgi.com, mingo@elte.hu Subject: Re: [PATCH 08/10] vmalloc: add un/map_kernel_range_noflush() References: <1234958676-27618-1-git-send-email-tj@kernel.org> <1234958676-27618-9-git-send-email-tj@kernel.org> <200902192317.28696.nickpiggin@yahoo.com.au> In-Reply-To: <200902192317.28696.nickpiggin@yahoo.com.au> X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0 (hera.kernel.org [127.0.0.1]); Fri, 20 Feb 2009 01:27:28 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Nick Piggin wrote: > On Wednesday 18 February 2009 23:04:34 Tejun Heo wrote: >> Impact: two more public map/unmap functions >> >> Implement map_kernel_range_noflush() and unmap_kernel_range_noflush(). >> These functions respectively map and unmap address range in kernel VM >> area but doesn't do any vcache or tlb flushing. These will be used by >> new percpu allocator. > > Hmm... I have no real issues with this, although the caller is going > to have to be very careful not to introduce bugs (which I'm sure you > were ;)). > > Maybe can you add comments specifying the minimum of which flushes > are required and when, to scare people away from using them? Yeap, will add comments. Thanks. -- tejun