From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Fri, 05 Oct 2018 17:05:58 +0200 (CEST) Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:58812 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by eddie.linux-mips.org with ESMTP id S23990947AbeJEPFzfizvA convert rfc822-to-8bit (ORCPT ); Fri, 5 Oct 2018 17:05:55 +0200 Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w95F4hXD027614 for ; Fri, 5 Oct 2018 11:05:53 -0400 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0b-001b2d01.pphosted.com with ESMTP id 2mx9pvab5g-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 05 Oct 2018 11:05:53 -0400 Received: from localhost by e06smtp05.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Fri, 5 Oct 2018 16:05:44 +0100 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w95F5h3u63897732 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 5 Oct 2018 15:05:43 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 1D453AE045; Fri, 5 Oct 2018 18:04:33 +0100 (BST) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C216EAE051; Fri, 5 Oct 2018 18:04:32 +0100 (BST) Received: from [9.148.204.169] (unknown [9.148.204.169]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 5 Oct 2018 18:04:32 +0100 (BST) Date: Fri, 05 Oct 2018 18:05:01 +0300 User-Agent: K-9 Mail for Android In-Reply-To: <8891277c7de92e93d3bfc409df95810ee6f103cd.camel@kernel.crashing.org> References: <1538687224-17535-1-git-send-email-rppt@linux.vnet.ibm.com> <8891277c7de92e93d3bfc409df95810ee6f103cd.camel@kernel.crashing.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Subject: Re: [PATCH] memblock: stop using implicit alignement to SMP_CACHE_BYTES To: Benjamin Herrenschmidt , linux-mm@kvack.org CC: linux-mips@linux-mips.org, Michal Hocko , linux-ia64@vger.kernel.org, Catalin Marinas , Richard Weinberger , Russell King , Ingo Molnar , Geert Uytterhoeven , Matt Turner , linux-um@lists.infradead.org, linux-m68k@vger.kernel.org, Thomas Gleixner , Guan Xuetao , linux-arm-kernel@lists.infradead.org, Chris Zankel , Michal Simek , Tony Luck , linux-kernel@vger.kernel.org, Paul Burton , linux-alpha@vger.kernel.org, Andrew Morton , linuxppc-dev@lists.ozlabs.org From: Mike Rapoport X-TM-AS-GCONF: 00 x-cbid: 18100515-0020-0000-0000-000002D00A38 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18100515-0021-0000-0000-0000211E6102 Message-Id: <59C9470E-F718-4A11-BC65-FD68901723AC@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-10-05_08:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=680 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1810050153 Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 66704 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: rppt@linux.vnet.ibm.com Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips On October 5, 2018 6:25:38 AM GMT+03:00, Benjamin Herrenschmidt wrote: >On Fri, 2018-10-05 at 00:07 +0300, Mike Rapoport wrote: >> When a memblock allocation APIs are called with align = 0, the >alignment is >> implicitly set to SMP_CACHE_BYTES. >> >> Replace all such uses of memblock APIs with the 'align' parameter >explicitly >> set to SMP_CACHE_BYTES and stop implicit alignment assignment in the >> memblock internal allocation functions. >> >> For the case when memblock APIs are used via helper functions, e.g. >like >> iommu_arena_new_node() in Alpha, the helper functions were detected >with >> Coccinelle's help and then manually examined and updated where >appropriate. >> >> The direct memblock APIs users were updated using the semantic patch >below: > >What is the purpose of this ? It sounds rather counter-intuitive... Why? I think it actually more intuitive to explicitly set alignment to SMP_CACHE_BYTES rather than use align = 0 because deeply inside allocator it will be implicitly reset to SMP_CACHE_BYTES... >Ben. -- Sincerely yours, Mike.