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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 1F1C5C4360C for ; Sun, 29 Sep 2019 00:45:31 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A88BE2146E for ; Sun, 29 Sep 2019 00:45:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A88BE2146E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id E614E6B0003; Sat, 28 Sep 2019 20:45:29 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E11AD6B0005; Sat, 28 Sep 2019 20:45:29 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D28156B0006; Sat, 28 Sep 2019 20:45:29 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0184.hostedemail.com [216.40.44.184]) by kanga.kvack.org (Postfix) with ESMTP id B25226B0003 for ; Sat, 28 Sep 2019 20:45:29 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id 4666C181AC9BF for ; Sun, 29 Sep 2019 00:45:29 +0000 (UTC) X-FDA: 75986114778.25.women14_8727db1d28f53 X-HE-Tag: women14_8727db1d28f53 X-Filterd-Recvd-Size: 3424 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by imf04.hostedemail.com (Postfix) with ESMTP for ; Sun, 29 Sep 2019 00:45:28 +0000 (UTC) X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 28 Sep 2019 17:45:26 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,561,1559545200"; d="scan'208";a="215284978" Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by fmsmga004.fm.intel.com with ESMTP; 28 Sep 2019 17:45:25 -0700 Date: Sun, 29 Sep 2019 08:45:07 +0800 From: Wei Yang To: Andrew Morton Cc: Wei Yang , aarcange@redhat.com, hughd@google.com, mike.kravetz@oracle.com, linux-mm@kvack.org Subject: Re: [PATCH v2 1/3] userfaultfd: use vma_pagesize for all huge page size calculation Message-ID: <20190929004507.GA11770@richard> Reply-To: Wei Yang References: <20190927070032.2129-1-richardw.yang@linux.intel.com> <20190927151033.aad57472652a0b3a6948df6e@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190927151033.aad57472652a0b3a6948df6e@linux-foundation.org> User-Agent: Mutt/1.9.4 (2018-02-28) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Sep 27, 2019 at 03:10:33PM -0700, Andrew Morton wrote: >On Fri, 27 Sep 2019 15:00:30 +0800 Wei Yang wrote: > >> In function __mcopy_atomic_hugetlb, we use two variables to deal with >> huge page size: vma_hpagesize and huge_page_size. >> >> Since they are the same, it is not necessary to use two different >> mechanism. This patch makes it consistent by all using vma_hpagesize. >> >> --- a/mm/userfaultfd.c >> +++ b/mm/userfaultfd.c >> @@ -262,7 +262,7 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm, >> pte_t dst_pteval; >> >> BUG_ON(dst_addr >= dst_start + len); >> - VM_BUG_ON(dst_addr & ~huge_page_mask(h)); >> + VM_BUG_ON(dst_addr & (vma_hpagesize - 1)); >> >> /* >> * Serialize via hugetlb_fault_mutex >> @@ -273,7 +273,7 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm, >> mutex_lock(&hugetlb_fault_mutex_table[hash]); >> >> err = -ENOMEM; >> - dst_pte = huge_pte_alloc(dst_mm, dst_addr, huge_page_size(h)); >> + dst_pte = huge_pte_alloc(dst_mm, dst_addr, vma_hpagesize); >> if (!dst_pte) { >> mutex_unlock(&hugetlb_fault_mutex_table[hash]); >> goto out_unlock; >> @@ -300,7 +300,8 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm, >> >> err = copy_huge_page_from_user(page, >> (const void __user *)src_addr, >> - pages_per_huge_page(h), true); >> + vma_hpagesize / PAGE_SIZE, >> + true); >> if (unlikely(err)) { >> err = -EFAULT; >> goto out; > >Looks right. > >We could go ahead and remove local variable `h', given that >hugetlb_fault_mutex_hash() doesn't actually use its first arg.. Oops, haven't imagine h is not used in the function. Any historical reason to pass h in hugetlb_fault_mutex_hash()? Neither these two definition use it. -- Wei Yang Help you, Help me