From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932837AbbKDPWJ (ORCPT ); Wed, 4 Nov 2015 10:22:09 -0500 Received: from mx2.suse.de ([195.135.220.15]:55566 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932303AbbKDPWG (ORCPT ); Wed, 4 Nov 2015 10:22:06 -0500 Subject: Re: [RESEND PATCH v2] thp: Remove unused vma parameter from khugepaged_alloc_page To: Aaron Tomlin , akpm@linux-foundation.org References: <1446641335-5603-1-git-send-email-atomlin@redhat.com> Cc: riel@redhat.com, lwoodman@redhat.com, aarcange@redhat.com, kirill.shutemov@linux.intel.com, mgorman@suse.de, willy@linux.intel.com, aneesh.kumar@linux.vnet.ibm.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org From: Vlastimil Babka Message-ID: <563A229A.4030000@suse.cz> Date: Wed, 4 Nov 2015 16:22:02 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: <1446641335-5603-1-git-send-email-atomlin@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/04/2015 01:48 PM, Aaron Tomlin wrote: > Resending due to incomplete subject. > > Changes since v2: > > - Fixed incorrect commit message > > The "vma" parameter to khugepaged_alloc_page() is unused. > It has to remain unused or the drop read lock 'map_sem' optimisation > introduce by commit 8b1645685acf ("mm, THP: don't hold mmap_sem in > khugepaged when allocating THP") wouldn't be safe. So let's remove it. > > Signed-off-by: Aaron Tomlin Pretty sure the compiler inlines it away anyway, but sure, why not. Acked-by: Vlastimil Babka > --- > mm/huge_memory.c | 8 +++----- > 1 file changed, 3 insertions(+), 5 deletions(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index bbac913..490fa81 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -2413,8 +2413,7 @@ static bool khugepaged_prealloc_page(struct page **hpage, bool *wait) > > static struct page * > khugepaged_alloc_page(struct page **hpage, gfp_t gfp, struct mm_struct *mm, > - struct vm_area_struct *vma, unsigned long address, > - int node) > + unsigned long address, int node) > { > VM_BUG_ON_PAGE(*hpage, *hpage); > > @@ -2481,8 +2480,7 @@ static bool khugepaged_prealloc_page(struct page **hpage, bool *wait) > > static struct page * > khugepaged_alloc_page(struct page **hpage, gfp_t gfp, struct mm_struct *mm, > - struct vm_area_struct *vma, unsigned long address, > - int node) > + unsigned long address, int node) > { > up_read(&mm->mmap_sem); > VM_BUG_ON(!*hpage); > @@ -2530,7 +2528,7 @@ static void collapse_huge_page(struct mm_struct *mm, > __GFP_THISNODE; > > /* release the mmap_sem read lock. */ > - new_page = khugepaged_alloc_page(hpage, gfp, mm, vma, address, node); > + new_page = khugepaged_alloc_page(hpage, gfp, mm, address, node); > if (!new_page) > return; > >