From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CCE2AC28CC0 for ; Thu, 30 May 2019 11:10:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9C2F1257E0 for ; Thu, 30 May 2019 11:10:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="u4F0Vrc/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726664AbfE3LKP (ORCPT ); Thu, 30 May 2019 07:10:15 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:36068 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725440AbfE3LKP (ORCPT ); Thu, 30 May 2019 07:10:15 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x4UB8pSx193271; Thu, 30 May 2019 11:08:51 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=content-type : mime-version : subject : from : in-reply-to : date : cc : content-transfer-encoding : message-id : references : to; s=corp-2018-07-02; bh=YCfDGCrbkbS0YzG5aLJic/fCahkN+gvlIX71eGLwvvQ=; b=u4F0Vrc/ic1PGIu0LqZqq8jbY5MJOpHhRMgBPVAZ8jxeIyYCupZPqo32+6EVKnq32Ufx gIBRlsxR7JUKj035DCe6EoN57oV+xmXDQl5X0NcMUp9cexxEcuS/EpvsUha0LTLnBvKQ /emUELgWHhZ96/z2L7+IloQ5afZT32gZT0F6eE0N9aWmY1ukfQJ9xqkLjwmu0Gypn+uC LeVyaN47Io/P6TqxhYel8yGbNrsDrE1XUBJ9DaLMmQhJQAHOuZg1jKfBU9DGP0XoyB5d F/SqFMAd9Q1cWD1RKBu+NY9PuOGBlYeJCkdZp2J8TAEofrjUx+/luOLPCWWc2ELXXIAG Zg== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2130.oracle.com with ESMTP id 2spw4tqd0w-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 30 May 2019 11:08:51 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x4UB8Pwq175460; Thu, 30 May 2019 11:08:50 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3020.oracle.com with ESMTP id 2sqh748cxn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 30 May 2019 11:08:50 +0000 Received: from abhmp0018.oracle.com (abhmp0018.oracle.com [141.146.116.24]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x4UB8kmd004283; Thu, 30 May 2019 11:08:46 GMT Received: from [192.168.0.110] (/73.243.10.6) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 30 May 2019 04:08:45 -0700 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.11\)) Subject: Re: [PATCH uprobe, thp 3/4] uprobe: support huge page by only splitting the pmd From: William Kucharski In-Reply-To: <20190529212049.2413886-4-songliubraving@fb.com> Date: Thu, 30 May 2019 05:08:43 -0600 Cc: LKML , Linux-MM , namit@vmware.com, Peter Zijlstra , oleg@redhat.com, Steven Rostedt , mhiramat@kernel.org, Matthew Wilcox , kirill.shutemov@linux.intel.com, kernel-team@fb.com, Chad Mynhier , mike.kravetz@oracle.com Content-Transfer-Encoding: 7bit Message-Id: <6D76CB61-CF13-4610-A883-0C25ECC5CFB7@oracle.com> References: <20190529212049.2413886-1-songliubraving@fb.com> <20190529212049.2413886-4-songliubraving@fb.com> To: Song Liu X-Mailer: Apple Mail (2.3445.104.11) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9272 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905300085 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9272 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905300085 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Is there any reason to worry about supporting PUD-sized uprobe pages if CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD is defined? I would prefer not to bake in the assumption that "huge" means PMD-sized and more than it already is. For example, if CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD is configured, mm_address_trans_huge() should either make the call to pud_trans_huge() if appropriate, or a VM_BUG_ON_PAGE should be added in case the routine is ever called with one. Otherwise it looks pretty reasonable to me. -- Bill