From: Yongqiang Yang Subject: Do we really need parallel resizer? Date: Fri, 24 Jun 2011 16:41:43 +0800 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Cc: Ext4 Developers List To: adilger@dilger.ca Return-path: Received: from mail-pv0-f174.google.com ([74.125.83.174]:38502 "EHLO mail-pv0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751569Ab1FXIlp (ORCPT ); Fri, 24 Jun 2011 04:41:45 -0400 Received: by pvg12 with SMTP id 12so1599624pvg.19 for ; Fri, 24 Jun 2011 01:41:44 -0700 (PDT) Sender: linux-ext4-owner@vger.kernel.org List-ID: Hi Andreas, I noticed that resize is protected by resize_lock. Then parallel resizer works. However, I think there is no need to make parallel resizer work. I think we can use an atomic integer 'resize_flag' instead of resize_lock, resize_flag is set to 1 before the kernel does resizing work, while resize_flag is set to 0 after the kernel finishes resizing work. Resizing is allowed only if resize_flag is 0. If resize_flag is 1, kernel returns -EBUSY to userspace. What about your opinion? Yongqiang. -- Best Wishes Yongqiang Yang