Re: [PATCH v11 7/7] mm: add vm event counters for balloon pages compaction

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Nov 07, 2012 at 01:05:54AM -0200, Rafael Aquini wrote:
> This patch introduces a new set of vm event counters to keep track of
> ballooned pages compaction activity.
> 
> Signed-off-by: Rafael Aquini <aquini@redhat.com>
> ---
>  drivers/virtio/virtio_balloon.c |  1 +
>  include/linux/vm_event_item.h   |  8 +++++++-
>  mm/balloon_compaction.c         |  2 ++
>  mm/migrate.c                    |  1 +
>  mm/vmstat.c                     | 10 +++++++++-
>  5 files changed, 20 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
> index 69eede7..3756fc1 100644
> --- a/drivers/virtio/virtio_balloon.c
> +++ b/drivers/virtio/virtio_balloon.c
> @@ -411,6 +411,7 @@ int virtballoon_migratepage(struct address_space *mapping,
>  	tell_host(vb, vb->deflate_vq);
>  
>  	mutex_unlock(&vb->balloon_lock);
> +	balloon_event_count(COMPACTBALLOONMIGRATED);
>  
>  	return MIGRATEPAGE_BALLOON_SUCCESS;
>  }

Looks like any ballon would need to do this.
Can this  chunk go into caller instead?

> diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h
> index 3d31145..cbd72fc 100644
> --- a/include/linux/vm_event_item.h
> +++ b/include/linux/vm_event_item.h
> @@ -41,7 +41,13 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
>  #ifdef CONFIG_COMPACTION
>  		COMPACTBLOCKS, COMPACTPAGES, COMPACTPAGEFAILED,
>  		COMPACTSTALL, COMPACTFAIL, COMPACTSUCCESS,
> -#endif
> +#ifdef CONFIG_BALLOON_COMPACTION
> +		COMPACTBALLOONISOLATED, /* isolated from balloon pagelist */
> +		COMPACTBALLOONMIGRATED, /* balloon page sucessfully migrated */
> +		COMPACTBALLOONRELEASED, /* old-page released after migration */
> +		COMPACTBALLOONRETURNED, /* putback to pagelist, not-migrated */
> +#endif /* CONFIG_BALLOON_COMPACTION */
> +#endif /* CONFIG_COMPACTION */
>  #ifdef CONFIG_HUGETLB_PAGE
>  		HTLB_BUDDY_PGALLOC, HTLB_BUDDY_PGALLOC_FAIL,
>  #endif
> diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c
> index 90935aa..32927eb 100644
> --- a/mm/balloon_compaction.c
> +++ b/mm/balloon_compaction.c
> @@ -215,6 +215,7 @@ bool balloon_page_isolate(struct page *page)
>  			if (__is_movable_balloon_page(page) &&
>  			    page_count(page) == 2) {
>  				__isolate_balloon_page(page);
> +				balloon_event_count(COMPACTBALLOONISOLATED);
>  				unlock_page(page);
>  				return true;
>  			}
> @@ -237,6 +238,7 @@ void balloon_page_putback(struct page *page)
>  	if (__is_movable_balloon_page(page)) {
>  		__putback_balloon_page(page);
>  		put_page(page);
> +		balloon_event_count(COMPACTBALLOONRETURNED);
>  	} else {
>  		__WARN();
>  		dump_page(page);
> diff --git a/mm/migrate.c b/mm/migrate.c
> index adb3d44..ee3037d 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -896,6 +896,7 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
>  				    page_is_file_cache(page));
>  		put_page(page);
>  		__free_page(page);
> +		balloon_event_count(COMPACTBALLOONRELEASED);
>  		return 0;
>  	}
>  out:
> diff --git a/mm/vmstat.c b/mm/vmstat.c
> index c737057..1363edc 100644
> --- a/mm/vmstat.c
> +++ b/mm/vmstat.c
> @@ -781,7 +781,15 @@ const char * const vmstat_text[] = {
>  	"compact_stall",
>  	"compact_fail",
>  	"compact_success",
> -#endif
> +
> +#ifdef CONFIG_BALLOON_COMPACTION
> +	"compact_balloon_isolated",
> +	"compact_balloon_migrated",
> +	"compact_balloon_released",
> +	"compact_balloon_returned",
> +#endif /* CONFIG_BALLOON_COMPACTION */
> +
> +#endif /* CONFIG_COMPACTION */
>  
>  #ifdef CONFIG_HUGETLB_PAGE
>  	"htlb_buddy_alloc_success",
> -- 
> 1.7.11.7