From: "NeilBrown" <neilb@suse.de>
Subject: Re: Link performance over NFS degraded in RHEL5. -- was :
     Read/Write NFS I/O performance degraded by FLUSH_STABLE page flushing
Date: Tue, 16 Jun 2009 10:21:50 +1000 (EST)
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Cc: "Trond Myklebust" <trond.myklebust@fys.uio.no>,
	"Steve Dickson" <steved@redhat.com>,
	"Tom Talpey" <tmtalpey@gmail.com>,
	"Linux NFS Mailing list" <linux-nfs@vger.kernel.org>
To: "J. Bruce Fields" <bfields@fieldses.org>
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On Tue, June 16, 2009 9:08 am, J. Bruce Fields wrote:

> +	if (host_err >= 0 && stable)
> +		wait_for_concurrent_writes(file, use_wgather, &host_err);
>

Surely you want this to be:

   if (host_err >= 0 && stable && use_wgather)
         host_err = wait_for_concurrent_writes(file);
as
 - this is more readable
 - setting last_ino and last_dev is pointless when !use_wgather
 - we aren't interested in differentiation between non-negative values of
   host_err.

NeilBrown