[Cluster-devel] [PATCH] GFS2: Patch to protect sd_log_num_jdata

[Steven Whitehouse <swhiteho@redhat.com>]

Hi,

Now in the -nmw git tree. Thanks,

Steve.

On Wed, 2007-08-22 at 11:15 -0500, Bob Peterson wrote:
> Hi,
> 
> This is a patch to GFS2 to protect sd_log_num_jdata with the
> gfs2_log_lock.  Without this patch, there is a timing window
> where you can get hit the following assert from function
> gfs2_log_flush():
> 
> gfs2_assert_withdraw(sdp,
> 			sdp->sd_log_num_buf + sdp->sd_log_num_jdata ==
> 			sdp->sd_log_commited_buf +
> 			sdp->sd_log_commited_databuf);
> 
> I've tested it on my roth cluster and it fixes the problem.
> 
> Regards,
> 
> Bob Peterson
> --
> diff -pur a/fs/gfs2/lops.c b/fs/gfs2/lops.c
> --- a/fs/gfs2/lops.c	2007-08-21 18:01:07.000000000 -0500
> +++ b/fs/gfs2/lops.c	2007-08-21 18:13:33.000000000 -0500
> @@ -492,11 +492,12 @@ static void databuf_lo_add(struct gfs2_s
>  
>  	gfs2_trans_add_gl(bd->bd_gl);
>  	if (gfs2_is_jdata(ip)) {
> -		sdp->sd_log_num_jdata++;
>  		gfs2_pin(sdp, bd->bd_bh);
>  		tr->tr_num_databuf_new++;
>  	}
>  	gfs2_log_lock(sdp);
> +	if (gfs2_is_jdata(ip))
> +		sdp->sd_log_num_jdata++;
>  	sdp->sd_log_num_databuf++;
>  	list_add(&le->le_list, &sdp->sd_log_le_databuf);
>  	gfs2_log_unlock(sdp);
> 
>