Re: [PATCH 3/4] WorkStruct: Merge the pending bit into the wq_data pointer

[Randy Dunlap <randy.dunlap@oracle.com>]

On Mon, 20 Nov 2006 14:27:20 +0000 David Howells wrote:

> Reclaim a word from the size of the work_struct by folding the pending bit and
> the wq_data pointer together.  This shouldn't cause misalignment problems as
> all pointers should be at least 4-byte aligned.
> 
> Signed-Off-By: David Howells <dhowells@redhat.com>
> ---
> 
>  drivers/block/floppy.c    |    4 ++--
>  include/linux/workqueue.h |   19 +++++++++++++++----
>  kernel/workqueue.c        |   41 ++++++++++++++++++++++++++++++++---------
>  3 files changed, 49 insertions(+), 15 deletions(-)
> 
> diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
> index 0d5bbd4..67e6a7f 100644
> --- a/include/linux/workqueue.h
> +++ b/include/linux/workqueue.h
> @@ -14,11 +14,15 @@ struct workqueue_struct;
>  typedef void (*work_func_t)(void *data);
>  
>  struct work_struct {
> -	unsigned long pending;
> +	/* the first word is the work queue pointer and the pending flag
> +	 * rolled into one */
> +	unsigned long management;
> +#define WORK_STRUCT_PENDING 0		/* T if work item pending execution */

Does 'T' mean true?  I think Linus's comment applies here also.

> +#define WORK_STRUCT_FLAG_MASK (3UL)
> +#define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK)
>  	struct list_head entry;
>  	work_func_t func;
>  	void *data;
> -	void *wq_data;
>  };
>  
>  struct dwork_struct {

---
~Randy