From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id EB4396B002D for ; Fri, 18 Nov 2011 16:21:37 -0500 (EST) Received: by bke17 with SMTP id 17so5234059bke.14 for ; Fri, 18 Nov 2011 13:21:29 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1321634598-16859-1-git-send-email-m.szyprowski@samsung.com> References: <1321634598-16859-1-git-send-email-m.szyprowski@samsung.com> From: sandeep patil Date: Fri, 18 Nov 2011 13:20:48 -0800 Message-ID: Subject: Re: [Linaro-mm-sig] [PATCHv17 0/11] Contiguous Memory Allocator Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org List-ID: To: Marek Szyprowski Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, linux-mm@kvack.org, linaro-mm-sig@lists.linaro.org, Daniel Walker , Russell King , Arnd Bergmann , Jonathan Corbet , Mel Gorman , Michal Nazarewicz , Dave Hansen , Jesse Barker , Kyungmin Park , Ankita Garg , Andrew Morton , KAMEZAWA Hiroyuki On Fri, Nov 18, 2011 at 8:43 AM, Marek Szyprowski wrote: > Welcome everyone once again, > Please notice that this patch series is aimed to start further > discussion. There are still few issues that need to be resolved before > CMA will be really ready. The most hot problem is the issue with movable > pages that causes migration to fail from time to time. Our investigation > leads us to the point that these rare pages cannot be migrated because > there are some pending io operations on them. I am running a simple test to allocate contiguous regions and write a log on in a file on sdcard simultaneously. I can reproduce this migration failure 100% times with it. when I tracked the pages that failed to migrate, I found them on the buffer head lru list with a reference held on the buffer_head in the page, which causes drop_buffers() to fail. So, i guess my question is, until all the migration failures are tracked down and fixed, is there a plan to retry the contiguous allocation from a new range in the CMA region? ~ sandeep -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org