Re: [PATCH 1/3] writeback: send work item to queue_io, move_expired_inodes

[Jan Kara <jack@suse.cz>]

On Mon 22-08-11 11:38:45, Curt Wohlgemuth wrote:
> Instead of sending ->older_than_this to queue_io() and
> move_expired_inodes(), send the entire wb_writeback_work
> structure.  There are other fields of a work item that are
> useful in these routines and in tracepoints.
  Looks good. You can add: Acked-by: Jan Kara <jack@suse.cz>

> Signed-off-by: Curt Wohlgemuth <curtw@google.com>
> ---
>  fs/fs-writeback.c                |   16 ++++++++--------
>  include/trace/events/writeback.h |    5 +++--
>  2 files changed, 11 insertions(+), 10 deletions(-)
> 
> diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
> index 04cf3b9..f1f5f65 100644
> --- a/fs/fs-writeback.c
> +++ b/fs/fs-writeback.c
> @@ -251,7 +251,7 @@ static bool inode_dirtied_after(struct inode *inode, unsigned long t)
>   */
>  static int move_expired_inodes(struct list_head *delaying_queue,
>  			       struct list_head *dispatch_queue,
> -			       unsigned long *older_than_this)
> +			       struct wb_writeback_work *work)
>  {
>  	LIST_HEAD(tmp);
>  	struct list_head *pos, *node;
> @@ -262,8 +262,8 @@ static int move_expired_inodes(struct list_head *delaying_queue,
>  
>  	while (!list_empty(delaying_queue)) {
>  		inode = wb_inode(delaying_queue->prev);
> -		if (older_than_this &&
> -		    inode_dirtied_after(inode, *older_than_this))
> +		if (work->older_than_this &&
> +		    inode_dirtied_after(inode, *work->older_than_this))
>  			break;
>  		if (sb && sb != inode->i_sb)
>  			do_sb_sort = 1;
> @@ -302,13 +302,13 @@ out:
>   *                                           |
>   *                                           +--> dequeue for IO
>   */
> -static void queue_io(struct bdi_writeback *wb, unsigned long *older_than_this)
> +static void queue_io(struct bdi_writeback *wb, struct wb_writeback_work *work)
>  {
>  	int moved;
>  	assert_spin_locked(&wb->list_lock);
>  	list_splice_init(&wb->b_more_io, &wb->b_io);
> -	moved = move_expired_inodes(&wb->b_dirty, &wb->b_io, older_than_this);
> -	trace_writeback_queue_io(wb, older_than_this, moved);
> +	moved = move_expired_inodes(&wb->b_dirty, &wb->b_io, work);
> +	trace_writeback_queue_io(wb, work, moved);
>  }
>  
>  static int write_inode(struct inode *inode, struct writeback_control *wbc)
> @@ -651,7 +651,7 @@ long writeback_inodes_wb(struct bdi_writeback *wb, long nr_pages)
>  
>  	spin_lock(&wb->list_lock);
>  	if (list_empty(&wb->b_io))
> -		queue_io(wb, NULL);
> +		queue_io(wb, &work);
>  	__writeback_inodes_wb(wb, &work);
>  	spin_unlock(&wb->list_lock);
>  
> @@ -738,7 +738,7 @@ static long wb_writeback(struct bdi_writeback *wb,
>  
>  		trace_writeback_start(wb->bdi, work);
>  		if (list_empty(&wb->b_io))
> -			queue_io(wb, work->older_than_this);
> +			queue_io(wb, work);
>  		if (work->sb)
>  			progress = writeback_sb_inodes(work->sb, wb, work);
>  		else
> diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h
> index 6bca4cc..4565274 100644
> --- a/include/trace/events/writeback.h
> +++ b/include/trace/events/writeback.h
> @@ -181,9 +181,9 @@ DEFINE_WBC_EVENT(wbc_writepage);
>  
>  TRACE_EVENT(writeback_queue_io,
>  	TP_PROTO(struct bdi_writeback *wb,
> -		 unsigned long *older_than_this,
> +		 struct wb_writeback_work *work,
>  		 int moved),
> -	TP_ARGS(wb, older_than_this, moved),
> +	TP_ARGS(wb, work, moved),
>  	TP_STRUCT__entry(
>  		__array(char,		name, 32)
>  		__field(unsigned long,	older)
> @@ -191,6 +191,7 @@ TRACE_EVENT(writeback_queue_io,
>  		__field(int,		moved)
>  	),
>  	TP_fast_assign(
> +		unsigned long *older_than_this = work->older_than_this;
>  		strncpy(__entry->name, dev_name(wb->bdi->dev), 32);
>  		__entry->older	= older_than_this ?  *older_than_this : 0;
>  		__entry->age	= older_than_this ?
> -- 
> 1.7.3.1
> 
-- 
Jan Kara <jack@suse.cz>
SUSE Labs, CR