Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754078Ab1CJXZI (ORCPT ); Thu, 10 Mar 2011 18:25:08 -0500 Received: from mail3.caviumnetworks.com ([12.108.191.235]:18828 "EHLO mail3.caviumnetworks.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753398Ab1CJXZG (ORCPT ); Thu, 10 Mar 2011 18:25:06 -0500 Message-ID: <4D795DCE.7050807@caviumnetworks.com> Date: Thu, 10 Mar 2011 15:25:02 -0800 From: David Daney User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.15) Gecko/20101027 Fedora/3.0.10-1.fc12 Thunderbird/3.0.10 MIME-Version: 1.0 To: Steven Rostedt CC: Mathieu Desnoyers , Jason Baron , peterz@infradead.org, hpa@zytor.com, mingo@elte.hu, tglx@linutronix.de, andi@firstfloor.org, roland@redhat.com, rth@redhat.com, masami.hiramatsu.pt@hitachi.com, fweisbec@gmail.com, avi@redhat.com, davem@davemloft.net, sam@ravnborg.org, michael@ellerman.id.au, linux-kernel@vger.kernel.org, Ralf Baechle Subject: Re: [PATCH 0/2] jump label: update for .39 References: <1299780241.15854.393.camel@gandalf.stny.rr.com> <20110310182000.GB2906@redhat.com> <1299782143.15854.402.camel@gandalf.stny.rr.com> <4D791CAA.7090108@caviumnetworks.com> <1299783236.15854.405.camel@gandalf.stny.rr.com> <4D791F31.6040100@caviumnetworks.com> <1299785143.15854.407.camel@gandalf.stny.rr.com> <1299786329.15854.409.camel@gandalf.stny.rr.com> <1299793339.15854.430.camel@gandalf.stny.rr.com> <1299798970.15854.484.camel@gandalf.stny.rr.com> In-Reply-To: <1299798970.15854.484.camel@gandalf.stny.rr.com> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 10 Mar 2011 23:25:02.0287 (UTC) FILETIME=[615FE5F0:01CBDF7A] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1710 Lines: 39 On 03/10/2011 03:16 PM, Steven Rostedt wrote: > On Thu, 2011-03-10 at 17:48 -0500, Mathieu Desnoyers wrote: >> * Steven Rostedt (rostedt@goodmis.org) wrote: >>> On Thu, 2011-03-10 at 16:22 -0500, Mathieu Desnoyers wrote: >>> >>>>> Anyway, I think the best thing for now is to have Jason add >>>>> the .align(sizeof(long)) in the inline assembly for all locations and be >>>>> done with it. >>>> >>>> You seem to be contradicting yourself here. I'm concerned about having >>>> "structures" of a size not power of two. Can we simply either >>> >>> But we don't have structures. We have data that has been allocated in >>> assembly. Come to think of it, it may be best to keep these as >>> ".align 4". >> >> The .align 4 is certainly not the right answer, because it will trigger >> unaligned accesses on some 64-bit architectures, as we have faced with >> trace event. > > Will it? Seems that sparc does this regardless. > > Remember, this is 3 natural word sized objects, and vmlinux.ld starts > the section off with .ALIGN 8, hence, the section is already 8 byte > aligned, all objects within this section are 8 bytes (for 64bit archs, > and 4 bytes for 32bit), why would saying ".align 4" cause the linker to > add holes to make it 4 byte aligned when it is already 8 byte aligned. > The ".align 4" should work with both 32bit and 64bit archs. > It should work, but it hurts my eyes to see the source code forcing a 64-bit word to 32-bit alignment. David Daney -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/