Re: [PATCH 5/7] xfs: factor out a xlog_state_activate_iclog helper

[Brian Foster <bfoster@redhat.com>]

On Fri, Mar 06, 2020 at 07:31:35AM -0700, Christoph Hellwig wrote:
> Factor out the code to mark an iclog a active into a new helper.

"mark as active" or just "mark active"

> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---

Otherwise looks fine:

Reviewed-by: Brian Foster <bfoster@redhat.com>

>  fs/xfs/xfs_log.c | 68 +++++++++++++++++++++++++-----------------------
>  1 file changed, 36 insertions(+), 32 deletions(-)
> 
> diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
> index 45f7a6eaddea..d1accad13af4 100644
> --- a/fs/xfs/xfs_log.c
> +++ b/fs/xfs/xfs_log.c
> @@ -2536,6 +2536,38 @@ xlog_write(
>   *****************************************************************************
>   */
>  
> +static void
> +xlog_state_activate_iclog(
> +	struct xlog_in_core	*iclog,
> +	int			*changed)
> +{
> +	ASSERT(list_empty_careful(&iclog->ic_callbacks));
> +
> +	/*
> +	 * If the number of ops in this iclog indicate it just contains the
> +	 * dummy transaction, we can change state into IDLE (the second time
> +	 * around). Otherwise we should change the state into NEED a dummy.
> +	 * We don't need to cover the dummy.
> +	 */
> +	if (!*changed &&
> +	    iclog->ic_header.h_num_logops == cpu_to_be32(XLOG_COVER_OPS)) {
> +		*changed = 1;
> +	} else {
> +		/*
> +		 * We have two dirty iclogs so start over.  This could also be
> +		 * num of ops indicating this is not the dummy going out.
> +		 */
> +		*changed = 2;
> +	}
> +
> +	iclog->ic_state	= XLOG_STATE_ACTIVE;
> +	iclog->ic_offset = 0;
> +	iclog->ic_header.h_num_logops = 0;
> +	memset(iclog->ic_header.h_cycle_data, 0,
> +		sizeof(iclog->ic_header.h_cycle_data));
> +	iclog->ic_header.h_lsn = 0;
> +}
> +
>  /*
>   * An iclog has just finished IO completion processing, so we need to update
>   * the iclog state and propagate that up into the overall log state. Hence we
> @@ -2567,38 +2599,10 @@ xlog_state_clean_iclog(
>  	/* Walk all the iclogs to update the ordered active state. */
>  	iclog = log->l_iclog;
>  	do {
> -		if (iclog->ic_state == XLOG_STATE_DIRTY) {
> -			iclog->ic_state	= XLOG_STATE_ACTIVE;
> -			iclog->ic_offset       = 0;
> -			ASSERT(list_empty_careful(&iclog->ic_callbacks));
> -			/*
> -			 * If the number of ops in this iclog indicate it just
> -			 * contains the dummy transaction, we can
> -			 * change state into IDLE (the second time around).
> -			 * Otherwise we should change the state into
> -			 * NEED a dummy.
> -			 * We don't need to cover the dummy.
> -			 */
> -			if (!changed &&
> -			   (be32_to_cpu(iclog->ic_header.h_num_logops) ==
> -			   		XLOG_COVER_OPS)) {
> -				changed = 1;
> -			} else {
> -				/*
> -				 * We have two dirty iclogs so start over
> -				 * This could also be num of ops indicates
> -				 * this is not the dummy going out.
> -				 */
> -				changed = 2;
> -			}
> -			iclog->ic_header.h_num_logops = 0;
> -			memset(iclog->ic_header.h_cycle_data, 0,
> -			      sizeof(iclog->ic_header.h_cycle_data));
> -			iclog->ic_header.h_lsn = 0;
> -		} else if (iclog->ic_state == XLOG_STATE_ACTIVE)
> -			/* do nothing */;
> -		else
> -			break;	/* stop cleaning */
> +		if (iclog->ic_state == XLOG_STATE_DIRTY)
> +			xlog_state_activate_iclog(iclog, &changed);
> +		else if (iclog->ic_state != XLOG_STATE_ACTIVE)
> +			break;
>  		iclog = iclog->ic_next;
>  	} while (iclog != log->l_iclog);
>  
> -- 
> 2.24.1
>