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=-2.2 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 20FFBC4360C for ; Sat, 5 Oct 2019 00:35:14 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DB39B21D81 for ; Sat, 5 Oct 2019 00:35:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DB39B21D81 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 6A6306B0003; Fri, 4 Oct 2019 20:35:13 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 656DA6B0005; Fri, 4 Oct 2019 20:35:13 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 56C8D6B0006; Fri, 4 Oct 2019 20:35:13 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0057.hostedemail.com [216.40.44.57]) by kanga.kvack.org (Postfix) with ESMTP id 356F26B0003 for ; Fri, 4 Oct 2019 20:35:13 -0400 (EDT) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with SMTP id CC1498E4B for ; Sat, 5 Oct 2019 00:35:12 +0000 (UTC) X-FDA: 76007861664.20.fight53_67a700f813b4e X-HE-Tag: fight53_67a700f813b4e X-Filterd-Recvd-Size: 3742 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by imf29.hostedemail.com (Postfix) with ESMTP for ; Sat, 5 Oct 2019 00:35:12 +0000 (UTC) X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 04 Oct 2019 17:35:10 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.67,258,1566889200"; d="scan'208";a="195722250" Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by orsmga003.jf.intel.com with ESMTP; 04 Oct 2019 17:35:08 -0700 Date: Sat, 5 Oct 2019 08:34:50 +0800 From: Wei Yang To: Mike Kravetz Cc: Andrew Morton , Wei Yang , aarcange@redhat.com, hughd@google.com, linux-mm@kvack.org Subject: Re: [PATCH v2 1/3] userfaultfd: use vma_pagesize for all huge page size calculation Message-ID: <20191005003450.GA16122@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: 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 03:21:38PM -0700, Mike Kravetz wrote: >On 9/27/19 3:10 PM, 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.. > >Good catch Andrew. I missed that, but I also wrote the original code that >is being cleaned up. :) > I did a cleanup to remove the first parameter of function hugetlb_fault_mutex_hash(). Look forward your comment. >You can add, >Reviewed-by: Mike Kravetz >to the series. >-- >Mike Kravetz -- Wei Yang Help you, Help me