From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 5 Feb 2007 22:37:47 -0800 From: Andrew Morton Subject: Re: [RFC/PATCH] prepare_unmapped_area Message-Id: <20070205223747.d3494395.akpm@linux-foundation.org> In-Reply-To: <20070206061211.GA5549@wotan.suse.de> References: <200702060405.l1645R7G009668@shell0.pdx.osdl.net> <1170736938.2620.213.camel@localhost.localdomain> <20070206044516.GA16647@wotan.suse.de> <1170738296.2620.220.camel@localhost.localdomain> <20070205213130.308a8c76.akpm@linux-foundation.org> <1170740760.2620.222.camel@localhost.localdomain> <20070205215827.a1a8ccdd.akpm@linux-foundation.org> <20070206061211.GA5549@wotan.suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Nick Piggin Cc: Benjamin Herrenschmidt , hugh@veritas.com, Linux Memory Management List-ID: On Tue, 6 Feb 2007 07:12:11 +0100 Nick Piggin wrote: > On Mon, Feb 05, 2007 at 09:58:27PM -0800, Andrew Morton wrote: > > On Tue, 06 Feb 2007 16:46:00 +1100 Benjamin Herrenschmidt wrote: > > > > > On Mon, 2007-02-05 at 21:31 -0800, Andrew Morton wrote: > > > > On Tue, 06 Feb 2007 16:04:56 +1100 Benjamin Herrenschmidt wrote: > > > > > > > > > +#ifndef HAVE_ARCH_PREPARE_UNMAPPED_AREA > > > > > +int arch_prepare_unmapped_area(struct file *file, unsigned long addr, > > > > > > > > __attribute__((weak)), please. > > > > > > Not sure about that ... it will usually be inline, in fact, should be > > > static inline... > > > > > > > Bah. function calls are fast, mmap() is slow and ARCH_HAVE_FOO is fugly. > > It still costs a whole nother cacheline, for just an empty function on > !hugepage kernels. Doubtful, especially with CONFIG_CC_OPTIMIZE_FOR_SIZE=y. > > Alternative: implement include/asm-*/arch-mmap.h and put the implementation > > in there. That way, we can lose HAVE_ARCH_UNMAPPED_AREA and maybe a few other > > things too. > > Yes please. It's a heck of a lot of fuss, adding 20-odd new files. If we're sure that we can use it for other things then maybe.. -- 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