From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sun, 1 Jun 2003 16:33:39 +0200 From: Ingo Oeser Subject: Re: build problems on architectures where FIXADDR_* stuff is not constant Message-ID: <20030601163339.D659@nightmaster.csn.tu-chemnitz.de> References: <20030513122329.GA31609@namesys.com> <20030513134620.3dafeaf3.akpm@digeo.com> <20030513232450.Y626@nightmaster.csn.tu-chemnitz.de> <20030513181227.0c068200.akpm@digeo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030513181227.0c068200.akpm@digeo.com>; from akpm@digeo.com on Tue, May 13, 2003 at 06:12:27PM -0700 Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: linux-mm@kvack.org List-ID: Hi Andrew, I finally got around to handle this issue. On Tue, May 13, 2003 at 06:12:27PM -0700, Andrew Morton wrote: > Ingo Oeser wrote: > > > > What, if you fold a part of my page_walker code (the special case > > for one page actually) into the baseline? > > > > This will resolve the issue and should remove the vma argument > > from get_user_pages(). > > > > It will also speed up that path a little. > > > > What do you think? > > I'd be interested in seeing a diff. Especially if it > digs that crap out of get_user_pages(). Yes, but the change would be quite big: - follow_hugetlb_pages() is not needed anymore, since follow_page() can handle them and every user of get_user_pages() needing to get a vma back is just needing exactly one page. Required users of a possible get_single_user_page(): fs/binfmt_elf.c:elf_core_dump() kernel/ptrace.c:access_process_vm() Recommended users (because they need only one page): kernel/futex.c:__pin_page() arch/i386/lib/usercopy.c:_copy_to_user_ll() - get_user_pages() will loose its last argument. I could also remove the force argument then, since drivers/media/video/video-buf.c is the only user and it looks bogus to me wrt. this usage. - the FIXADDR handling would have its own inline function, degenerating into a assignement, if not needed and might be duplicated partially, if inlined. - the follow_page and faulting would become a own function. - all callers of both functions must be updated and it will affect the pgcl patches. So the amount of changes is quite similiar to the inclusion of the whole new page-walking-api. If you want pieces, please tell me, which of the changes above you want. Regards Ingo Oeser -- 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: aart@kvack.org