From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932489AbXBSTey (ORCPT ); Mon, 19 Feb 2007 14:34:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932515AbXBSTey (ORCPT ); Mon, 19 Feb 2007 14:34:54 -0500 Received: from e35.co.us.ibm.com ([32.97.110.153]:49369 "EHLO e35.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932489AbXBSTex (ORCPT ); Mon, 19 Feb 2007 14:34:53 -0500 Subject: Re: [PATCH 0/7] [RFC] hugetlb: pagetable_operations API From: Adam Litke To: Arjan van de Ven Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org In-Reply-To: <1171910581.3531.89.camel@laptopd505.fenrus.org> References: <20070219183123.27318.27319.stgit@localhost.localdomain> <1171910581.3531.89.camel@laptopd505.fenrus.org> Content-Type: text/plain Date: Mon, 19 Feb 2007 13:34:51 -0600 Message-Id: <1171913691.22940.30.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.8.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2007-02-19 at 19:43 +0100, Arjan van de Ven wrote: > On Mon, 2007-02-19 at 10:31 -0800, Adam Litke wrote: > > The page tables for hugetlb mappings are handled differently than page tables > > for normal pages. Rather than integrating multiple page size support into the > > main VM (which would tremendously complicate the code) some hooks were created. > > This allows hugetlb special cases to be handled "out of line" by a separate > > interface. > > ok it makes sense to clean this up.. what I don't like is that there > STILL are all the double cases... for this to work and be worth it both > the common case and the hugetlb case should be using the ops structure > always! Anything else and you're just replacing bad code with bad > code ;( Hmm. Do you think everyone would support an extra pointer indirection for every handle_pte_fault() call? If not, then I definitely wouldn't mind creating a default_pagetable_ops and calling into that. -- Adam Litke - (agl at us.ibm.com) IBM Linux Technology Center From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from d03relay04.boulder.ibm.com (d03relay04.boulder.ibm.com [9.17.195.106]) by e32.co.us.ibm.com (8.12.11.20060308/8.13.8) with ESMTP id l1JJY9UH030698 for ; Mon, 19 Feb 2007 14:34:09 -0500 Received: from d03av01.boulder.ibm.com (d03av01.boulder.ibm.com [9.17.195.167]) by d03relay04.boulder.ibm.com (8.13.8/8.13.8/NCO v8.2) with ESMTP id l1JJYqGo518994 for ; Mon, 19 Feb 2007 12:34:52 -0700 Received: from d03av01.boulder.ibm.com (loopback [127.0.0.1]) by d03av01.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id l1JJYqeQ005437 for ; Mon, 19 Feb 2007 12:34:52 -0700 Subject: Re: [PATCH 0/7] [RFC] hugetlb: pagetable_operations API From: Adam Litke In-Reply-To: <1171910581.3531.89.camel@laptopd505.fenrus.org> References: <20070219183123.27318.27319.stgit@localhost.localdomain> <1171910581.3531.89.camel@laptopd505.fenrus.org> Content-Type: text/plain Date: Mon, 19 Feb 2007 13:34:51 -0600 Message-Id: <1171913691.22940.30.camel@localhost.localdomain> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Arjan van de Ven Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: On Mon, 2007-02-19 at 19:43 +0100, Arjan van de Ven wrote: > On Mon, 2007-02-19 at 10:31 -0800, Adam Litke wrote: > > The page tables for hugetlb mappings are handled differently than page tables > > for normal pages. Rather than integrating multiple page size support into the > > main VM (which would tremendously complicate the code) some hooks were created. > > This allows hugetlb special cases to be handled "out of line" by a separate > > interface. > > ok it makes sense to clean this up.. what I don't like is that there > STILL are all the double cases... for this to work and be worth it both > the common case and the hugetlb case should be using the ops structure > always! Anything else and you're just replacing bad code with bad > code ;( Hmm. Do you think everyone would support an extra pointer indirection for every handle_pte_fault() call? If not, then I definitely wouldn't mind creating a default_pagetable_ops and calling into that. -- Adam Litke - (agl at us.ibm.com) IBM Linux Technology Center -- 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