From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755929AbZBCQza (ORCPT ); Tue, 3 Feb 2009 11:55:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752485AbZBCQzO (ORCPT ); Tue, 3 Feb 2009 11:55:14 -0500 Received: from mail.mellanox.co.il ([194.90.237.43]:58848 "EHLO mellanox.co.il" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755164AbZBCQzM (ORCPT ); Tue, 3 Feb 2009 11:55:12 -0500 X-Greylist: delayed 399 seconds by postgrey-1.27 at vger.kernel.org; Tue, 03 Feb 2009 11:55:11 EST Date: Tue, 3 Feb 2009 18:49:30 +0200 From: Eli Cohen To: linux-kernel@vger.kernel.org, Roland Dreier Subject: [PATCH] powerpc/mm: Export HPAGE_SHIFT Message-ID: <20090203164930.GA10101@mtls03> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.17+20080114 (2008-01-14) X-OriginalArrivalTime: 03 Feb 2009 16:48:27.0842 (UTC) FILETIME=[3CC4FA20:01C9861F] X-TM-AS-Product-Ver: SMEX-8.0.0.1181-5.500.1027-16442.000 X-TM-AS-Result: No--5.470300-8.000000-31 X-TM-AS-User-Approved-Sender: No X-TM-AS-User-Blocked-Sender: No Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Drivers may want to take advantage of the large pages used for memory obtained from hugetlbfs. One example is mlx4_ib which can use much less MTT entries (in the order of HPAGE_SIZE / PAGE_SIZE) when registering such memory, thus scale significantly better when registering larger memory regions. Other drivers could also benefit from this. Signed-off-by: Eli Cohen --- arch/powerpc/mm/hash_utils_64.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c index 8d5b475..6cff8c7 100644 --- a/arch/powerpc/mm/hash_utils_64.c +++ b/arch/powerpc/mm/hash_utils_64.c @@ -104,6 +104,7 @@ int mmu_highuser_ssize = MMU_SEGSIZE_256M; u16 mmu_slb_size = 64; #ifdef CONFIG_HUGETLB_PAGE unsigned int HPAGE_SHIFT; +EXPORT_SYMBOL(HPAGE_SHIFT); #endif #ifdef CONFIG_PPC_64K_PAGES int mmu_ci_restrictions; -- 1.6.1