Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754586Ab2E1Lov (ORCPT ); Mon, 28 May 2012 07:44:51 -0400 Received: from natasha.panasas.com ([67.152.220.90]:47683 "EHLO natasha.panasas.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753746Ab2E1Lou (ORCPT ); Mon, 28 May 2012 07:44:50 -0400 Message-ID: <4FC364F9.4090308@panasas.com> Date: Mon, 28 May 2012 14:43:53 +0300 From: Boaz Harrosh User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:8.0) Gecko/20111113 Thunderbird/8.0 MIME-Version: 1.0 To: Peng Tao CC: Trond Myklebust , "J. Bruce Fields" , , , , , , , , , , , Steve Dickson Subject: Re: [PATCH 4/5] NFS: remove RPC PipeFS mount point reference from blocklayout routines References: <20111129090754.20730.64567.stgit@localhost6.localdomain6> <20111129091037.20730.59391.stgit@localhost6.localdomain6> <4ED4CDCE.9080804@parallels.com> <2E1EB2CF9ED1CB4AA966F0EB76EAB4430C3CBC23@SACMVEXC2-PRD.hq.netapp.com> <1322579906.3619.1.camel@lade.trondhjem.org> <1322584830.4174.16.camel@lade.trondhjem.org> <20111129164252.GA19528@fieldses.org> <1322587165.4174.20.camel@lade.trondhjem.org> In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1584 Lines: 46 On 11/29/2011 07:30 PM, Peng Tao wrote: > On Wed, Nov 30, 2011 at 1:19 AM, Trond Myklebust > wrote: >> On Tue, 2011-11-29 at 11:42 -0500, J. Bruce Fields wrote: >>> On Tue, Nov 29, 2011 at 11:40:30AM -0500, Trond Myklebust wrote: >>>> I mean that I'm perfectly entitled to do >>>> >>>> 'modprobe -r blocklayoutdriver' >>>> >>>> and when I do that, then I expect blkmapd to close the rpc pipe and wait >>>> for a new one to be created just like rpc.idmapd and rpc.gssd do when I >>>> remove the nfs and sunrpc modules. >>> >>> The rpc pipefs mount doesn't hold a reference on the sunrpc module? >> >> I stand corrected: the mount does hold a reference to the sunrpc >> module. >> However nothing holds a reference to the blocklayoutdriver module, so >> the main point that the "blocklayout" pipe can disappear from underneath >> the blkmapd stands. > Thanks for the explanation and I agree it can cause problem if user > reload blocklayout module. I will look into a fix to blkmapd. > You might want to consider converting to call_usermodehelper() I know that it greatly simplified our code both in Kernel and in user-mode. And it made nfs-utils maintainer much happier as well. The speed is not Cardinal here I think. Like in objects it's done once per new device_id > Best, > Tao Just my $0.017 Boaz -- 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/