From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qg0-f42.google.com (mail-qg0-f42.google.com [209.85.192.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id ADE591A1A4B for ; Wed, 22 Jul 2015 14:47:05 +1000 (AEST) Received: by qgy5 with SMTP id 5so97917052qgy.3 for ; Tue, 21 Jul 2015 21:47:03 -0700 (PDT) Message-ID: <55AF2037.2000803@linaro.org> Date: Wed, 22 Jul 2015 00:46:47 -0400 From: David Long MIME-Version: 1.0 To: Michael Ellerman CC: Rob Herring , "H. Peter Anvin" , Andy Lutomirski , Anton Blanchard , Behan Webster , Benjamin Herrenschmidt , Eric Paris , Heiko Carstens , Ingo Molnar , Jan Willeke , Kees Cook , Martin Schwidefsky , Nikolay Borisov , Oleg Nesterov , Paul Mackerras , Richard Kuo , Robert Richter , Roland McGrath , Russell King , Tejun Heo , Thomas Gleixner , Will Deacon , "linux-arm-kernel@lists.infradead.org" , linux-hexagon@vger.kernel.org, "linux-kernel@vger.kernel.org" , linux-s390@vger.kernel.org, SH-Linux , linux390@de.ibm.com, linuxppc-dev , "x86@kernel.org" Subject: Re: [PATCH 1/2] Move the pt_regs_offset struct definition from arch to common include file References: <1434386579-6045-1-git-send-email-dave.long@linaro.org> <1434386579-6045-2-git-send-email-dave.long@linaro.org> <5581BCD0.2040405@linaro.org> <1435634945.24866.2.camel@ellerman.id.au> In-Reply-To: <1435634945.24866.2.camel@ellerman.id.au> Content-Type: text/plain; charset=UTF-8; format=flowed List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 06/29/15 23:29, Michael Ellerman wrote: > On Wed, 2015-06-17 at 14:30 -0400, David Long wrote: >> On 06/16/15 09:17, Rob Herring wrote: >>> On Mon, Jun 15, 2015 at 11:42 AM, David Long wrote: >>>> >>>> #define REG_OFFSET_NAME(r) \ >>>> {.name = #r, .offset = offsetof(struct pt_regs, ARM_##r)} >>>> #define REG_OFFSET_END {.name = NULL, .offset = 0} >>> >>> Can't you also move these? ARM is complicated with the "ARM_" >>> prefixing, but the others appear to be the same. Maybe you can remove >>> the prefix or redefine the macro for ARM. >> >> That would mandate that all the architecture-specific pt_regs structures >> would have to use a top-level named field for each named register. > > Why does it mandate that? > > See eg. powerpc where we use REG_OFFSET_NAME for the top-level named fields and > then a different macro for the array elements: > > #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} > #define GPR_OFFSET_NAME(num) \ > {.name = STR(gpr##num), .offset = offsetof(struct pt_regs, gpr[num])} > > static const struct pt_regs_offset regoffset_table[] = { > GPR_OFFSET_NAME(0), > GPR_OFFSET_NAME(1), > GPR_OFFSET_NAME(2), > GPR_OFFSET_NAME(3), > ... > REG_OFFSET_NAME(nip), > REG_OFFSET_NAME(msr), > > > So I don't see why REG_OFFSET_NAME couldn't be common. > Sorry for the delay in responding to this. OK, so you're saying architectures that don't want this constraint can make their own macro. Seems to make this whole exercise slightly less useful, but whatever. I see three ways to go here: 1) Leave it as is. 2) Force all architectures to use a common definition. 3) Provide a common definition that all architectures (except "arm") currently using this functionality will use. I have a v2 patch to implement #3, ready to post. Do we think this is the way to go? I don't like #2 because I really don't want to rename all uses of the current register fields for arm since this is architecture-specific code to begin with and since it affects code in 39 arm source files. > cheers > Thanks, -dl