From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Daney Subject: Re: [PATCH v6 13/14] arm64, acpi, numa: NUMA support based on SRAT and SLIT Date: Thu, 12 May 2016 08:27:08 -0700 Message-ID: <5734A0CC.8010600@caviumnetworks.com> References: <1461780436-27182-1-git-send-email-ddaney.cavm@gmail.com> <1461780436-27182-14-git-send-email-ddaney.cavm@gmail.com> <20160511103929.GC3051@e104818-lin.cambridge.arm.com> <5733C8F5.6090206@caviumnetworks.com> <20160512094915.GD11226@e104818-lin.cambridge.arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-bl2on0068.outbound.protection.outlook.com ([65.55.169.68]:41890 "EHLO na01-bl2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932279AbcELP1R (ORCPT ); Thu, 12 May 2016 11:27:17 -0400 In-Reply-To: <20160512094915.GD11226@e104818-lin.cambridge.arm.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Catalin Marinas , "Rafael J. Wysocki" , Will Deacon Cc: David Daney , Mark Rutland , linux-ia64@vger.kernel.org, David Daney , Lv Zheng , "H. Peter Anvin" , Frank Rowand , x86@kernel.org, Robert Moore , linux-acpi@vger.kernel.org, Ingo Molnar , Grant Likely , Len Brown , Fenghua Yu , Marc Zyngier , Jon Masters , Robert Richter , Rob Herring , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, devel@acpica.org, Tony Luck , linux-kernel@vger.kernel.org, Hanjun Guo , Ganapatrao Kulkarni On 05/12/2016 02:49 AM, Catalin Marinas wrote: > On Wed, May 11, 2016 at 05:06:13PM -0700, David Daney wrote: >> On 05/11/2016 03:39 AM, Catalin Marinas wrote: [...] >>> >>> I wonder whether you could replace the get_mpidr_in_madt() function with >>> something like acpi_get_phys_id(). It looks like get_mpidr_in_madt() >>> duplicates functionality already available elsewhere. >> >> I just tried that, and it doesn't work. >> >> The problem is that this code is being run very early in the boot, and >> kmalloc cannot be used. acpi_get_phys_id() and its ilk can only be used >> once we have working kmalloc. We need to extract the NUMA information early >> like this precisely because it is needed to initializing the slab system >> >> Notice that we are using early_acpi_os_unmap_memory() et al. in >> get_mpidr_in_madt() explicitly for this reason. >> >> In summary: I don't think we need another revision of this patch, it is like >> this for a good reason. > > Slightly confusing, in another reply you said you are going to address > my comment. So, is it doable? I don't think so. My previous reply, to the thread in 0/14, was prematurely made with the incorrect assumption that it was a simple change. Now, after really digging in to the code, and attempting to do as you suggested, I have changed my mind. As I indicated above, there are no remaining suggestions or requests for changes to this patch set pending action. Unless people find additional problems, I think it is ready for merging. I know that Will and Rafael were discussing the proper timing for merging this in the other thread, so I leave it in their hands at this point. Thanks, David Daney >