Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751965Ab2HaHKW (ORCPT ); Fri, 31 Aug 2012 03:10:22 -0400 Received: from e06smtp14.uk.ibm.com ([195.75.94.110]:47358 "EHLO e06smtp14.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751366Ab2HaHKT (ORCPT ); Fri, 31 Aug 2012 03:10:19 -0400 Date: Fri, 31 Aug 2012 09:10:12 +0200 From: Martin Schwidefsky To: "Aneesh Kumar K.V" Cc: Gerald Schaefer , Andrew Morton , Andrea Arcangeli , Andi Kleen , Hugh Dickins , Hillf Danton , linux-kernel@vger.kernel.org, Heiko Carstens Subject: Re: [RFC v2 PATCH 1/7] thp: remove assumptions on pgtable_t type Message-ID: <20120831091012.7b710326@de.ibm.com> In-Reply-To: <877gsf633x.fsf@linux.vnet.ibm.com> References: <1346254384-30046-1-git-send-email-gerald.schaefer@de.ibm.com> <1346254384-30046-2-git-send-email-gerald.schaefer@de.ibm.com> <877gsf633x.fsf@linux.vnet.ibm.com> Organization: IBM Corporation X-Mailer: Claws Mail 3.8.1 (GTK+ 2.24.10; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit x-cbid: 12083107-1948-0000-0000-000002D16110 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1225 Lines: 32 On Fri, 31 Aug 2012 10:59:38 +0530 "Aneesh Kumar K.V" wrote: > Gerald Schaefer writes: > > > The thp page table pre-allocation code currently assumes that pgtable_t > > is of type "struct page *". This may not be true for all architectures, > > so this patch removes that assumption by replacing the functions > > prepare_pmd_huge_pte() and get_pmd_huge_pte() with two new functions > > that can be defined architecture-specific. > > > > It also removes two VM_BUG_ON checks for page_count() and page_mapcount() > > operating on a pgtable_t. Apart from the VM_BUG_ON removal, there will > > be no functional change introduced by this patch. > > Why is that VM_BUG_ON not needed any more ? What is that changed which break > that requirement ? Because pgtable_t for s390 is not a page and there simply is no page_count or page_mapcount. -- blue skies, Martin. "Reality continues to ruin my life." - Calvin. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/