From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ravikiran G Thirumalai Subject: Re: [PATCH 1/2] ext3 percpu counter fixes to suppport for more than 2**31 ext3 free blocks counter Date: Fri, 21 Apr 2006 17:56:49 -0700 Message-ID: <20060422005649.GA3817@localhost.localdomain> References: <1144691929.3964.53.camel@dyn9047017067.beaverton.ibm.com> <1145631546.4478.10.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: akpm@osdl.org, LaurentVivier@wanadoo.fr, sct@redhat.com, linux-kernel@vger.kernel.org, ext2-devel , linux-fsdevel@vger.kernel.org Return-path: Received: from ns1.siteground.net ([207.218.208.2]:696 "EHLO serv01.siteground.net") by vger.kernel.org with ESMTP id S1750802AbWDVAzn (ORCPT ); Fri, 21 Apr 2006 20:55:43 -0400 To: Mingming Cao Content-Disposition: inline In-Reply-To: <1145631546.4478.10.camel@localhost.localdomain> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Fri, Apr 21, 2006 at 07:59:06AM -0700, Mingming Cao wrote: > The following patches are to fix the percpu counter issue support more > than 2**31 blocks for ext3, i.e. allow the ext3 free block accounting > works with more than 8TB storage. > > [PATCH 1] - Generic perpcu longlong type counter support: global counter > type changed from long to long long. The local counter is still remains > 32 bit (long type), so we could avoid doing 64 bit update in most cases. > Fixed the percpu_counter_read_positive() to handle the 0 value counter > correctly;Add support to initialize the global counter to a value that > are greater than 2**32. > > [PATCH 2] - ext3 part of the changes: make use of the new support to > initialize the free blocks counter, instead of using percpu_counter_mod > () indirectly. > > Patches against 2.6.17-rc1-mm2. Tested on a freshly created 10TB ext3. > > Here is Patch 1. > > Signed-Off-By: Mingming Cao > > ... > +static inline void > +percpu_counter_ll_init(struct percpu_counter *fbc, long long amount) > +{ > + spin_lock_init(&fbc->lock); > + fbc->count = amount; > + fbc->counters = alloc_percpu(long); > +} > + Do we need another interface for this? Why not change percpu_counter_init and users to use 'amount' as an additional argument instead? Thanks, Kiran