[Cluster-devel] [GFS2 PATCH] Get rid of gl_waiters2

[Steven Whitehouse <swhiteho@redhat.com>]

Hi,

Now in the -nmw git tree. Thanks,

Steve.

On Mon, 2008-01-28 at 22:31 -0600, Bob Peterson wrote:
> Hi,
> 
> This patch reduces memory by replacing the int variable
> gl_waiters2 by a single bit in the gl_flags.
> 
> Regards,
> 
> Bob Peterson
> Red Hat GFS
> 
> Signed-off-by: Bob Peterson <rpeterso@redhat.com> 
> --
>  fs/gfs2/glock.c  |    7 ++++---
>  fs/gfs2/incore.h |    4 ++--
>  2 files changed, 6 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
> index 894c70e..aa6f32e 100644
> --- a/fs/gfs2/glock.c
> +++ b/fs/gfs2/glock.c
> @@ -594,11 +594,12 @@ static void run_queue(struct gfs2_glock *gl)
>  			blocked = rq_mutex(gh);
>  		} else if (test_bit(GLF_DEMOTE, &gl->gl_flags)) {
>  			blocked = rq_demote(gl);
> -			if (gl->gl_waiters2 && !blocked) {
> +			if (test_bit(GLF_WAITERS2, &gl->gl_flags) &&
> +				     !blocked) {
>  				set_bit(GLF_DEMOTE, &gl->gl_flags);
>  				gl->gl_demote_state = LM_ST_UNLOCKED;
>  			}
> -			gl->gl_waiters2 = 0;
> +			clear_bit(GLF_WAITERS2, &gl->gl_flags);
>  		} else if (!list_empty(&gl->gl_waiters3)) {
>  			gh = list_entry(gl->gl_waiters3.next,
>  					struct gfs2_holder, gh_list);
> @@ -704,7 +705,7 @@ static void handle_callback(struct gfs2_glock *gl, unsigned int state,
>  	} else if (gl->gl_demote_state != LM_ST_UNLOCKED &&
>  			gl->gl_demote_state != state) {
>  		if (test_bit(GLF_DEMOTE_IN_PROGRESS,  &gl->gl_flags)) 
> -			gl->gl_waiters2 = 1;
> +			set_bit(GLF_WAITERS2, &gl->gl_flags);
>  		else 
>  			gl->gl_demote_state = LM_ST_UNLOCKED;
>  	}
> diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
> index ab682c0..217ecb0 100644
> --- a/fs/gfs2/incore.h
> +++ b/fs/gfs2/incore.h
> @@ -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
> @@ -167,6 +167,7 @@ enum {
>  	GLF_DIRTY		= 5,
>  	GLF_DEMOTE_IN_PROGRESS	= 6,
>  	GLF_LFLUSH		= 7,
> +	GLF_WAITERS2		= 8,
>  };
>  
>  struct gfs2_glock {
> @@ -186,7 +187,6 @@ struct gfs2_glock {
>  	struct list_head gl_holders;
>  	struct list_head gl_waiters1;	/* HIF_MUTEX */
>  	struct list_head gl_waiters3;	/* HIF_PROMOTE */
> -	int gl_waiters2;		/* GIF_DEMOTE */
>  
>  	const struct gfs2_glock_operations *gl_ops;
>  
> 
>