Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754838Ab3CDCHh (ORCPT ); Sun, 3 Mar 2013 21:07:37 -0500 Received: from mail-pb0-f47.google.com ([209.85.160.47]:34382 "EHLO mail-pb0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752449Ab3CDCHg (ORCPT ); Sun, 3 Mar 2013 21:07:36 -0500 Date: Mon, 4 Mar 2013 10:07:47 +0800 From: Greg KH To: "K. Y. Srinivasan" Cc: linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, olaf@aepfle.de, apw@canonical.com, andi@firstfloor.org, akpm@linux-foundation.org, linux-mm@kvack.org Subject: Re: [PATCH 1/1] mm: Export split_page(). Message-ID: <20130304020747.GA8265@kroah.com> References: <1362364075-14564-1-git-send-email-kys@microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1362364075-14564-1-git-send-email-kys@microsoft.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1492 Lines: 39 On Sun, Mar 03, 2013 at 06:27:55PM -0800, K. Y. Srinivasan wrote: > The split_page() function will be very useful for balloon drivers. On Hyper-V, > it will be very efficient to use 2M allocations in the guest as this (a) makes > the ballooning protocol with the host that much more efficient and (b) moving > memory in 2M chunks minimizes fragmentation in the host. Export the split_page() > function to let the guest allocations be in 2M chunks while the host is free to > return this memory at arbitrary granularity. > > > Signed-off-by: K. Y. Srinivasan > --- > mm/page_alloc.c | 1 + > 1 files changed, 1 insertions(+), 0 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 6cacfee..7e0ead6 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1404,6 +1404,7 @@ void split_page(struct page *page, unsigned int order) > for (i = 1; i < (1 << order); i++) > set_page_refcounted(page + i); > } > +EXPORT_SYMBOL_GPL(split_page); When you export a symbol, you also need to post the code that is going to use that symbol, otherwise people don't really know how to judge this request. Can you just make this a part of your balloon driver update patch series instead? thanks, greg k-h -- 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/