[Cluster-devel] [GFS2 PATCH] GFS2: Made logd daemon take into account log demand

[Steven Whitehouse]

Hi,

Both patches look good to me,

Steve.


On 05/01/17 21:11, Bob Peterson wrote:
> Hi,
>
> Before this patch, the logd daemon only tried to flush things when
> the log blocks pinned exceeded a certain threshold. But when we're
> deleting very large files, it may require a huge number of journal
> blocks, and that, in turn, may exceed the threshold. This patch
> factors that into account.
>
> Signed-off-by: Bob Peterson <rpeterso at redhat.com>
> ---
> diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
> index a6a3389..00d8dc2 100644
> --- a/fs/gfs2/incore.h
> +++ b/fs/gfs2/incore.h
> @@ -794,6 +794,7 @@ struct gfs2_sbd {
>   	atomic_t sd_log_thresh1;
>   	atomic_t sd_log_thresh2;
>   	atomic_t sd_log_blks_free;
> +	atomic_t sd_log_blks_needed;
>   	wait_queue_head_t sd_log_waitq;
>   	wait_queue_head_t sd_logd_waitq;
>   
> diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
> index e58ccef0..4df349c 100644
> --- a/fs/gfs2/log.c
> +++ b/fs/gfs2/log.c
> @@ -349,6 +349,7 @@ int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
>   	if (gfs2_assert_warn(sdp, blks) ||
>   	    gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
>   		return -EINVAL;
> +	atomic_add(blks, &sdp->sd_log_blks_needed);
>   retry:
>   	free_blocks = atomic_read(&sdp->sd_log_blks_free);
>   	if (unlikely(free_blocks <= wanted)) {
> @@ -370,6 +371,7 @@ retry:
>   			wake_up(&sdp->sd_reserving_log_wait);
>   		goto retry;
>   	}
> +	atomic_sub(blks, &sdp->sd_log_blks_needed);
>   	trace_gfs2_log_blocks(sdp, -blks);
>   
>   	/*
> @@ -891,13 +893,16 @@ void gfs2_log_shutdown(struct gfs2_sbd *sdp)
>   
>   static inline int gfs2_jrnl_flush_reqd(struct gfs2_sbd *sdp)
>   {
> -	return (atomic_read(&sdp->sd_log_pinned) >= atomic_read(&sdp->sd_log_thresh1));
> +	return (atomic_read(&sdp->sd_log_pinned) +
> +		atomic_read(&sdp->sd_log_blks_needed) >=
> +		atomic_read(&sdp->sd_log_thresh1));
>   }
>   
>   static inline int gfs2_ail_flush_reqd(struct gfs2_sbd *sdp)
>   {
>   	unsigned int used_blocks = sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free);
> -	return used_blocks >= atomic_read(&sdp->sd_log_thresh2);
> +	return used_blocks + atomic_read(&sdp->sd_log_blks_needed) >=
> +		atomic_read(&sdp->sd_log_thresh2);
>   }
>   
>   /**
> diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
> index ff72ac6..86281a9 100644
> --- a/fs/gfs2/ops_fstype.c
> +++ b/fs/gfs2/ops_fstype.c
> @@ -683,6 +683,7 @@ static int init_journal(struct gfs2_sbd *sdp, int undo)
>   		goto fail_jindex;
>   	}
>   
> +	atomic_set(&sdp->sd_log_blks_needed, 0);
>   	if (sdp->sd_args.ar_spectator) {
>   		sdp->sd_jdesc = gfs2_jdesc_find(sdp, 0);
>   		atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
>