From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <xfs-bounce@oss.sgi.com>
Received: with ECARTIS (v1.0.0; list xfs); Sun, 19 Aug 2007 12:29:09 -0700 (PDT)
Received: from pentafluge.infradead.org (pentafluge.infradead.org [213.146.154.40])
	by oss.sgi.com (8.12.10/8.12.10/SuSE Linux 0.7) with ESMTP id l7JJT4bm014235
	for <xfs@oss.sgi.com>; Sun, 19 Aug 2007 12:29:06 -0700
Date: Sun, 19 Aug 2007 20:08:47 +0100
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH] optimize XFS_IS_REALTIME_INODE w/o realtime config
Message-ID: <20070819190847.GB2929@infradead.org>
References: <46C7627A.60503@sandeen.net>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <46C7627A.60503@sandeen.net>
Sender: xfs-bounce@oss.sgi.com
Errors-to: xfs-bounce@oss.sgi.com
List-Id: xfs
To: Eric Sandeen <sandeen@sandeen.net>
Cc: xfs-oss <xfs@oss.sgi.com>

On Sat, Aug 18, 2007 at 04:19:54PM -0500, Eric Sandeen wrote:
> Use XFS_IS_REALTIME_INODE in more places, and #define it to
> 0 if CONFIG_XFS_RT is off.  This should be safe because mount
> checks in xfs_rtmount_init:
> 
> # define xfs_rtmount_init(m)    (((mp)->m_sb.sb_rblocks == 0)? 0 : (ENOSYS))
> 
> so if we get mounted w/o CONFIG_XFS_RT, no realtime inodes should
> be encountered after that.
> 
> Defining XFS_IS_REALTIME_INODE to 0 saves a bit of stack space,
> presumeably gcc can optimize around the various "if (0)" type
> checks:

Looks good to me.

Not sure if anyone disables the rt volume, but as long as it's a config
option we should try to avoid as much as possible away if it's not enabled.