[Cluster-devel] [GFS2 PATCH] Remove rgrp and glock version numbers

[Steven Whitehouse <swhiteho@redhat.com>]

Hi,

Now in the -nmw git tree. Thanks,

Steve.

On Thu, 2008-01-31 at 10:31 -0600, Bob Peterson wrote:
> Hi,
> 
> This patch further reduces GFS2's memory requirements by
> eliminating the 64-bit version number fields in lieu of
> a couple bits.
> 
> Regards,
> 
> Bob Peterson
> Red Hat GFS
> 
> Signed-off-by: Bob Peterson <rpeterso@redhat.com> 
> --
>  fs/gfs2/glock.c      |    3 +--
>  fs/gfs2/glops.c      |   10 ++++++++--
>  fs/gfs2/incore.h     |    5 ++---
>  fs/gfs2/ops_fstype.c |    4 ++--
>  fs/gfs2/rgrp.c       |   14 +++++++-------
>  5 files changed, 20 insertions(+), 16 deletions(-)
> 
> diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
> index 78cd1cd..e4ae1ef 100644
> --- a/fs/gfs2/glock.c
> +++ b/fs/gfs2/glock.c
> @@ -1,6 +1,6 @@
>  /*
>   * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
> - * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
> + * Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
>   *
>   * This copyrighted material is made available to anyone wishing to use,
>   * modify, copy, or redistribute it subject to the terms and conditions
> @@ -338,7 +338,6 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
>  	gl->gl_ip = 0;
>  	gl->gl_ops = glops;
>  	gl->gl_req_gh = NULL;
> -	gl->gl_vn = 0;
>  	gl->gl_stamp = jiffies;
>  	gl->gl_tchange = jiffies;
>  	gl->gl_object = NULL;
> diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
> index c663b7a..d31bada 100644
> --- a/fs/gfs2/glops.c
> +++ b/fs/gfs2/glops.c
> @@ -1,6 +1,6 @@
>  /*
>   * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
> - * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
> + * Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
>   *
>   * This copyrighted material is made available to anyone wishing to use,
>   * modify, copy, or redistribute it subject to the terms and conditions
> @@ -126,7 +126,13 @@ static void meta_go_inval(struct gfs2_glock *gl, int flags)
>  		return;
>  
>  	gfs2_meta_inval(gl);
> -	gl->gl_vn++;
> +	if (gl->gl_object == GFS2_I(gl->gl_sbd->sd_rindex))
> +		gl->gl_sbd->sd_rindex_uptodate = 0;
> +	else if (gl->gl_ops == &gfs2_rgrp_glops && gl->gl_object) {
> +		struct gfs2_rgrpd *rgd = (struct gfs2_rgrpd *)gl->gl_object;
> +
> +		rgd->rd_flags &= ~GFS2_RDF_UPTODATE;
> +	}
>  }
>  
>  /**
> diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
> index bf3c673..35e2459 100644
> --- a/fs/gfs2/incore.h
> +++ b/fs/gfs2/incore.h
> @@ -85,7 +85,6 @@ struct gfs2_rgrpd {
>  	u32 rd_data;			/* num of data blocks in rgrp */
>  	u32 rd_bitbytes;		/* number of bytes in data bitmaps */
>  	struct gfs2_rgrp_host rd_rg;
> -	u64 rd_rg_vn;
>  	struct gfs2_bitmap *rd_bits;
>  	unsigned int rd_bh_count;
>  	struct mutex rd_mutex;
> @@ -97,6 +96,7 @@ struct gfs2_rgrpd {
>  	unsigned char rd_flags;
>  #define GFS2_RDF_CHECK        0x01      /* Need to check for unlinked inodes */
>  #define GFS2_RDF_NOALLOC      0x02      /* rg prohibits allocation */
> +#define GFS2_RDF_UPTODATE     0x04      /* rg is up to date */
>  };
>  
>  enum gfs2_state_bits {
> @@ -196,7 +196,6 @@ struct gfs2_glock {
>  	char *gl_lvb;
>  	atomic_t gl_lvb_count;
>  
> -	u64 gl_vn;
>  	unsigned long gl_stamp;
>  	unsigned long gl_tchange;
>  	void *gl_object;
> @@ -531,7 +530,7 @@ struct gfs2_sbd {
>  
>  	/* Resource group stuff */
>  
> -	u64 sd_rindex_vn;
> +	int sd_rindex_uptodate;
>  	spinlock_t sd_rindex_spin;
>  	struct mutex sd_rindex_mutex;
>  	struct list_head sd_rindex_list;
> diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
> index 43d511b..f02261c 100644
> --- a/fs/gfs2/ops_fstype.c
> +++ b/fs/gfs2/ops_fstype.c
> @@ -1,6 +1,6 @@
>  /*
>   * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
> - * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
> + * Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
>   *
>   * This copyrighted material is made available to anyone wishing to use,
>   * modify, copy, or redistribute it subject to the terms and conditions
> @@ -542,7 +542,7 @@ static int init_inodes(struct gfs2_sbd *sdp, int undo)
>  	}
>  	ip = GFS2_I(sdp->sd_rindex);
>  	set_bit(GLF_STICKY, &ip->i_gl->gl_flags);
> -	sdp->sd_rindex_vn = ip->i_gl->gl_vn - 1;
> +	sdp->sd_rindex_uptodate = 0;
>  
>  	/* Read in the quota inode */
>  	sdp->sd_quota_inode = gfs2_lookup_simple(sdp->sd_master_dir, "quota");
> diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
> index 5fd8710..3f10b1f 100644
> --- a/fs/gfs2/rgrp.c
> +++ b/fs/gfs2/rgrp.c
> @@ -540,7 +540,7 @@ static int read_rindex_entry(struct gfs2_inode *ip,
>  		return error;
>  
>  	rgd->rd_gl->gl_object = rgd;
> -	rgd->rd_rg_vn = rgd->rd_gl->gl_vn - 1;
> +	rgd->rd_flags &= ~GFS2_RDF_UPTODATE;
>  	rgd->rd_flags |= GFS2_RDF_CHECK;
>  	return error;
>  }
> @@ -576,7 +576,7 @@ static int gfs2_ri_update(struct gfs2_inode *ip)
>  		}
>  	}
>  
> -	sdp->sd_rindex_vn = ip->i_gl->gl_vn;
> +	sdp->sd_rindex_uptodate = 1;
>  	return 0;
>  }
>  
> @@ -610,7 +610,7 @@ static int gfs2_ri_update_special(struct gfs2_inode *ip)
>  		}
>  	}
>  
> -	sdp->sd_rindex_vn = ip->i_gl->gl_vn;
> +	sdp->sd_rindex_uptodate = 1;
>  	return 0;
>  }
>  
> @@ -643,9 +643,9 @@ int gfs2_rindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ri_gh)
>  		return error;
>  
>  	/* Read new copy from disk if we don't have the latest */
> -	if (sdp->sd_rindex_vn != gl->gl_vn) {
> +	if (!sdp->sd_rindex_uptodate) {
>  		mutex_lock(&sdp->sd_rindex_mutex);
> -		if (sdp->sd_rindex_vn != gl->gl_vn) {
> +		if (!sdp->sd_rindex_uptodate) {
>  			error = gfs2_ri_update(ip);
>  			if (error)
>  				gfs2_glock_dq_uninit(ri_gh);
> @@ -737,9 +737,9 @@ int gfs2_rgrp_bh_get(struct gfs2_rgrpd *rgd)
>  		}
>  	}
>  
> -	if (rgd->rd_rg_vn != gl->gl_vn) {
> +	if (!(rgd->rd_flags & GFS2_RDF_UPTODATE)) {
>  		gfs2_rgrp_in(rgd, (rgd->rd_bits[0].bi_bh)->b_data);
> -		rgd->rd_rg_vn = gl->gl_vn;
> +		rgd->rd_flags |= GFS2_RDF_UPTODATE;
>  	}
>  
>  	spin_lock(&sdp->sd_rindex_spin);
> 
>