[Cluster-devel] [RFC RHEL7 GFS2 PATCH 3/3] gfs2: ordered write list addendum patch

[Steven Whitehouse]

On 12/12/17 17:22, Abhi Das wrote:
> Trim the list in gfs2_ordered_write() as we run through it
> to write out inodes.
> Also attempt to remove an inode from the list after it is
> fsync'ed.
> Finally, call gfs2_ordered_write() in case we were not able
> to shrink the list in gfs2_ordered_shrink() in the hopes that
> it will eventually cause the list to shrink.
> ---
Ok. I see that question is answered in this patch... yes, that is a good 
plan to remove items from the list at this point. Again since we are 
iterating the list in ordered wait, we could remove items from the list 
then too, to avoid the additional loop,

Steve.

>   fs/gfs2/file.c   |  3 +++
>   fs/gfs2/incore.h |  1 +
>   fs/gfs2/log.c    | 13 +++++++++++--
>   fs/gfs2/log.h    |  4 +++-
>   fs/gfs2/quota.c  |  4 ++--
>   5 files changed, 20 insertions(+), 5 deletions(-)
>
> diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
> index 757ec66..75f9ac0 100644
> --- a/fs/gfs2/file.c
> +++ b/fs/gfs2/file.c
> @@ -697,6 +697,9 @@ static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
>   	if (mapping->nrpages)
>   		ret = filemap_fdatawait_range(mapping, start, end);
>   
> +	if (!ret && !ret1)
> +		gfs2_ordered_del_inode(ip, ORD_WHENCE_FSYNC);
> +
>   	return ret ? ret : ret1;
>   }
>   
> diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
> index 6fcad2a..93da360 100644
> --- a/fs/gfs2/incore.h
> +++ b/fs/gfs2/incore.h
> @@ -661,6 +661,7 @@ struct ord_stats {
>   	unsigned long os_rm_trunc;
>   	unsigned long os_rm_evict;
>   	unsigned long os_rm_wait;
> +	unsigned long os_rm_fsync;
>   	unsigned long os_rm_syncfs;
>   	unsigned long os_rm_write;
>   	unsigned long os_rm_setflags;
> diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
> index 6d618a1..4cfef47 100644
> --- a/fs/gfs2/log.c
> +++ b/fs/gfs2/log.c
> @@ -507,9 +507,13 @@ static void gfs2_ordered_write(struct gfs2_sbd *sdp)
>   	list_sort(NULL, &sdp->sd_log_le_ordered, &ip_cmp);
>   	while (!list_empty(&sdp->sd_log_le_ordered)) {
>   		ip = list_entry(sdp->sd_log_le_ordered.next, struct gfs2_inode, i_ordered);
> -		list_move(&ip->i_ordered, &written);
> -		if (ip->i_inode.i_mapping->nrpages == 0)
> +		if (ip->i_inode.i_mapping->nrpages == 0) {
> +			test_and_clear_bit(GIF_ORDERED, &ip->i_flags);
> +			list_del(&ip->i_ordered);
> +			ord_stats_adjust(sdp, -1, ORD_WHENCE_ORD_WRITE);
>   			continue;
> +		}
> +		list_move(&ip->i_ordered, &written);
>   		spin_unlock(&sdp->sd_ordered_lock);
>   		filemap_fdatawrite(ip->i_inode.i_mapping);
>   		spin_lock(&sdp->sd_ordered_lock);
> @@ -540,17 +544,22 @@ static void gfs2_ordered_wait(struct gfs2_sbd *sdp)
>   void gfs2_ordered_shrink(struct gfs2_sbd *sdp, int whence)
>   {
>   	struct gfs2_inode *ip, *tmp;
> +	bool removed;
>   
>   	spin_lock(&sdp->sd_ordered_lock);
>   	list_for_each_entry_safe(ip, tmp, &sdp->sd_log_le_ordered, i_ordered) {
>   		if (ip->i_inode.i_mapping->nrpages != 0)
>   			continue;
>   		if (test_and_clear_bit(GIF_ORDERED, &ip->i_flags)) {
> +			removed = true;
>   			list_del(&ip->i_ordered);
>   			ord_stats_adjust(sdp, -1, whence);
>   		}
>   	}
>   	spin_unlock(&sdp->sd_ordered_lock);
> +
> +	if (!removed)
> +		gfs2_ordered_write(sdp);
>   }
>   
>   void gfs2_ordered_del_inode(struct gfs2_inode *ip, int whence)
> diff --git a/fs/gfs2/log.h b/fs/gfs2/log.h
> index 80c8861..0bc3620 100644
> --- a/fs/gfs2/log.h
> +++ b/fs/gfs2/log.h
> @@ -55,7 +55,8 @@ enum {
>   	ORD_WHENCE_SYNCFS       = 3,
>   	ORD_WHENCE_ORD_WRITE    = 4,
>   	ORD_WHENCE_SETFLAGS     = 5,
> -	ORD_WHENCE_ADD          = 6,
> +	ORD_WHENCE_FSYNC        = 6,
> +	ORD_WHENCE_ADD          = 7,
>   };
>   
>   static inline void ord_stats_adjust(struct gfs2_sbd *sdp, int count, int whence)
> @@ -70,6 +71,7 @@ static inline void ord_stats_adjust(struct gfs2_sbd *sdp, int count, int whence)
>   	case ORD_WHENCE_SYNCFS:     os->os_rm_syncfs += -(count); break;
>   	case ORD_WHENCE_ORD_WRITE:  os->os_rm_write += -(count); break;
>   	case ORD_WHENCE_SETFLAGS:   os->os_rm_setflags += -(count); break;
> +	case ORD_WHENCE_FSYNC:      os->os_rm_fsync += -(count); break;
>   
>   	case ORD_WHENCE_ADD:        os->os_add += count; break;
>   	default: break;
> diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
> index 66c5126..63e3afa 100644
> --- a/fs/gfs2/quota.c
> +++ b/fs/gfs2/quota.c
> @@ -1575,11 +1575,11 @@ int gfs2_quotad(void *data)
>   
>   		printk(KERN_WARNING "Ord list Size:%lu +[add_inode:%lu] "
>   		       "-[trunc:%lu evict:%lu wait:%lu syncfs:%lu ord_write:%lu"
> -		       " setflags:%lu]\n", sdp->sd_ord_stats.os_ct,
> +		       " setflags:%lu fsync:%lu]\n", sdp->sd_ord_stats.os_ct,
>   		       sdp->sd_ord_stats.os_add, sdp->sd_ord_stats.os_rm_trunc,
>   		       sdp->sd_ord_stats.os_rm_evict, sdp->sd_ord_stats.os_rm_wait,
>   		       sdp->sd_ord_stats.os_rm_syncfs, sdp->sd_ord_stats.os_rm_write,
> -		       sdp->sd_ord_stats.os_rm_setflags);
> +		       sdp->sd_ord_stats.os_rm_setflags, sdp->sd_ord_stats.os_rm_fsync);
>   	}
>   
>   	return 0;