Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760797AbYFWRhc (ORCPT ); Mon, 23 Jun 2008 13:37:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754218AbYFWRhY (ORCPT ); Mon, 23 Jun 2008 13:37:24 -0400 Received: from hellhawk.shadowen.org ([80.68.90.175]:1606 "EHLO hellhawk.shadowen.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752355AbYFWRhX (ORCPT ); Mon, 23 Jun 2008 13:37:23 -0400 From: Andy Whitcroft To: Jon Tollefson Cc: Andrew Morton , Nick Piggin , Nishanth Aravamudan , Adam Litke , linux-kernel@vger.kernel.org, kernel-testers@vger.kernel.org, linux-mm@kvack.org, Mel Gorman , Andy Whitcroft Subject: [RFC] hugetlb reservations -- MAP_PRIVATE fixes for split vmas V2 Date: Mon, 23 Jun 2008 18:35:31 +0100 Message-Id: <1214242533-12104-1-git-send-email-apw@shadowen.org> X-Mailer: git-send-email 1.5.6.205.g7ca3a In-Reply-To: <485A8903.9030808@linux.vnet.ibm.com> References: <485A8903.9030808@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1448 Lines: 34 As reported by Adam Litke and Jon Tollefson one of the libhugetlbfs regression tests triggers a negative overall reservation count. When this occurs where there is no dynamic pool enabled tests will fail. Following this email are two patches to address this issue: hugetlb reservations: move region tracking earlier -- simply moves the region tracking code earlier so we do not have to supply prototypes, and hugetlb reservations: fix hugetlb MAP_PRIVATE reservations across vma splits -- which moves us to tracking the consumed reservation so that we can correctly calculate the remaining reservations at vma close time. This stack is against the top of v2.6.25-rc6-mm3, should this solution prove acceptable it would need slipping underneath Nick's multiple hugepage size patches and those updated. I have a modified stack prepared for that. This version incorporates Mel's feedback (both cosmetic, and an allocation under spinlock issue) and has an improved layout. Changes in V2: - commentry updates - pull allocations out from under hugetlb_lock - refactor to match shared code layout - reinstate BUG_ON's Jon could you have a test on this and see if it works out for you. -apw -- 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/