From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with ESMTP id 132146B0055 for ; Tue, 6 Oct 2009 12:28:55 -0400 (EDT) Subject: Re: [PATCH 11/11] hugetlb: offload per node attribute registrations From: Lee Schermerhorn In-Reply-To: <20091006160139.GT1656@one.firstfloor.org> References: <20091006031739.22576.5248.sendpatchset@localhost.localdomain> <20091006031924.22576.35018.sendpatchset@localhost.localdomain> <20091006160139.GT1656@one.firstfloor.org> Content-Type: text/plain Date: Tue, 06 Oct 2009 12:28:49 -0400 Message-Id: <1254846529.13943.69.camel@useless.americas.hpqcorp.net> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Andi Kleen Cc: linux-mm@kvack.org, linux-numa@vger.kernel.org, akpm@linux-foundation.org, Mel Gorman , Randy Dunlap , Nishanth Aravamudan , David Rientjes , Adam Litke , Andy Whitcroft , eric.whitney@hp.com List-ID: On Tue, 2009-10-06 at 18:01 +0200, Andi Kleen wrote: > On Mon, Oct 05, 2009 at 11:19:24PM -0400, Lee Schermerhorn wrote: > > [PATCH 11/11] hugetlb: offload [un]registration of sysfs attr to worker thread > > > > Against: 2.6.31-mmotm-090925-1435 > > > > New in V6 > > > > V7: + remove redundant check for memory{ful|less} node from > > node_hugetlb_work(). Rely on [added] return from > > hugetlb_register_node() to differentiate between transitions > > to/from memoryless state. > > > > This patch offloads the registration and unregistration of per node > > hstate sysfs attributes to a worker thread rather than attempt the > > allocation/attachment or detachment/freeing of the attributes in > > the context of the memory hotplug handler. > > Why this change? The hotplug handler should be allowed to sleep, shouldn't it? Andy: perhaps it can. I'm not familiar with hotplug, so I followed a pattern found elsewhere. I created a separate patch in case someone familiar with this area says I don't need it. > > > N.B., Only tested build, boot, libhugetlbfs regression. > > i.e., no memory hotplug testing. > > Yes, you have to because I know for a fact it's broken (outside your code) :) We need to be able to remove all memory from a node without that node disappearing [as I think it does on x86_64] to even exercise this code. I think some ia64 platforms can do that, perhaps others. Lee -- 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