From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [PATCH v5 6/7] x86/tlb: optimizing flush_tlb_mm Date: Tue, 15 May 2012 16:57:20 +0200 Message-ID: <1337093840.27694.56.camel@twins> References: <1337072138-8323-1-git-send-email-alex.shi@intel.com> <1337072138-8323-7-git-send-email-alex.shi@intel.com> <4FB2590C.1050303@intel.com> <1337092577.27694.45.camel@twins> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Return-path: Received: from merlin.infradead.org ([205.233.59.134]:53367 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751107Ab2EOO5w convert rfc822-to-8bit (ORCPT ); Tue, 15 May 2012 10:57:52 -0400 In-Reply-To: <1337092577.27694.45.camel@twins> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Alex Shi Cc: Nick Piggin , tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, arnd@arndb.de, rostedt@goodmis.org, fweisbec@gmail.com, jeremy@goop.org, riel@redhat.com, luto@mit.edu, avi@redhat.com, len.brown@intel.com, dhowells@redhat.com, fenghua.yu@intel.com, borislav.petkov@amd.com, yinghai@kernel.org, ak@linux.intel.com, cpw@sgi.com, steiner@sgi.com, akpm@linux-foundation.org, penberg@kernel.org, hughd@google.com, rientjes@google.com, kosaki.motohiro@jp.fujitsu.com, n-horiguchi@ah.jp.nec.com, tj@kernel.org, oleg@redhat.com, axboe@kernel.dk, jmorris@namei.org, kamezawa.hiroyu@jp.fujitsu.com, viro@zeniv.linux.org.uk, linux-kernel@vger.kernel.org, yongjie.ren@intel.com, linux-arch@vger.kernel.org On Tue, 2012-05-15 at 16:36 +0200, Peter Zijlstra wrote: > On Tue, 2012-05-15 at 21:24 +0800, Alex Shi wrote: > > > Sorry. I don't understand what's the comments Peter's made days ago. I should ask for more details originally. > > > > So, Peter, the correct change should like following, am I right? > > > > -#define tlb_flush(tlb) flush_tlb_mm((tlb)->mm) > > +#define tlb_flush(tlb, start, end) __flush_tlb_range((tlb)->mm, start, end) > > No.. the correct change is to do range tracking like the other archs > that support flush_tlb_range() do. > > You do not modify the tlb interface. > > Again, see: http://marc.info/?l=linux-arch&m=129952026504268&w=2 Just to be _very_ clear, you do not modify: mm/memory.c | 9 ++-- kernel/fork.c | 2 +- fs/proc/task_mmu.c | 2 +- As it stands your patch breaks compilation on a whole bunch of architectures. If you touch the TLB interface, you get to touch _ALL_ architectures.