From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf0-f70.google.com (mail-lf0-f70.google.com [209.85.215.70]) by kanga.kvack.org (Postfix) with ESMTP id 35F6F280251 for ; Tue, 18 Oct 2016 06:37:16 -0400 (EDT) Received: by mail-lf0-f70.google.com with SMTP id n3so8605144lfn.5 for ; Tue, 18 Oct 2016 03:37:16 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id 75si1053790lfq.347.2016.10.18.03.37.14 for (version=TLS1 cipher=AES128-SHA bits=128/128); Tue, 18 Oct 2016 03:37:14 -0700 (PDT) Date: Tue, 18 Oct 2016 12:37:12 +0200 From: Jan Kara Subject: Re: [PATCH 11/20] mm: Remove unnecessary vma->vm_ops check Message-ID: <20161018103712.GP3359@quack2.suse.cz> References: <1474992504-20133-1-git-send-email-jack@suse.cz> <1474992504-20133-12-git-send-email-jack@suse.cz> <20161017194041.GB21002@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161017194041.GB21002@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Ross Zwisler Cc: Jan Kara , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-nvdimm@lists.01.org, Dan Williams , "Kirill A. Shutemov" On Mon 17-10-16 13:40:41, Ross Zwisler wrote: > On Tue, Sep 27, 2016 at 06:08:15PM +0200, Jan Kara wrote: > > We don't check whether vma->vm_ops is NULL in do_shared_fault() so > > there's hardly any point in checking it in wp_page_shared() which gets > > called only for shared file mappings as well. > > > > Signed-off-by: Jan Kara > > --- > > mm/memory.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/mm/memory.c b/mm/memory.c > > index a4522e8999b2..63d9c1a54caf 100644 > > --- a/mm/memory.c > > +++ b/mm/memory.c > > @@ -2301,7 +2301,7 @@ static int wp_page_shared(struct vm_fault *vmf, struct page *old_page) > > > > get_page(old_page); > > > > - if (vma->vm_ops && vma->vm_ops->page_mkwrite) { > > + if (vma->vm_ops->page_mkwrite) { > > int tmp; > > > > pte_unmap_unlock(vmf->pte, vmf->ptl); > > -- > > 2.6.6 > > Does this apply equally to the check in wp_pfn_shared()? Both > wp_page_shared() and wp_pfn_shared() are called for shared file mappings via > do_wp_page(). Yes, it does apply there as well. Added to the commit. There are actually more places with these checks which don't seem necessary but I didn't want to do more cleanups than I need... But at least these two come logically together. Honza -- Jan Kara SUSE Labs, CR -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org