On 04/23/2015 11:03 PM, Kirill A. Shutemov wrote:
> The patch replaces THP_SPLIT with tree events: THP_SPLIT_PAGE,
> THP_SPLIT_PAGE_FAILT and THP_SPLIT_PMD. It reflects the fact that we

s/FAILT/FAILED

> are going to be able split PMD without the compound page and that
> split_huge_page() can fail.
> 
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> Acked-by: Christoph Lameter <cl@linux.com>
> Tested-by: Sasha Levin <sasha.levin@oracle.com>

Acked-by: Jerome Marchand <jmarchan@redhat.com>

> ---
>  include/linux/vm_event_item.h | 4 +++-
>  mm/huge_memory.c              | 2 +-
>  mm/vmstat.c                   | 4 +++-
>  3 files changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h
> index 2b1cef88b827..3261bfe2156a 100644
> --- a/include/linux/vm_event_item.h
> +++ b/include/linux/vm_event_item.h
> @@ -69,7 +69,9 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
>  		THP_FAULT_FALLBACK,
>  		THP_COLLAPSE_ALLOC,
>  		THP_COLLAPSE_ALLOC_FAILED,
> -		THP_SPLIT,
> +		THP_SPLIT_PAGE,
> +		THP_SPLIT_PAGE_FAILED,
> +		THP_SPLIT_PMD,
>  		THP_ZERO_PAGE_ALLOC,
>  		THP_ZERO_PAGE_ALLOC_FAILED,
>  #endif
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index ccbfacf07160..be6d0e0f5050 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -1961,7 +1961,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
>  
>  	BUG_ON(!PageSwapBacked(page));
>  	__split_huge_page(page, anon_vma, list);
> -	count_vm_event(THP_SPLIT);
> +	count_vm_event(THP_SPLIT_PAGE);
>  
>  	BUG_ON(PageCompound(page));
>  out_unlock:
> diff --git a/mm/vmstat.c b/mm/vmstat.c
> index 1fd0886a389f..e1c87425fe11 100644
> --- a/mm/vmstat.c
> +++ b/mm/vmstat.c
> @@ -821,7 +821,9 @@ const char * const vmstat_text[] = {
>  	"thp_fault_fallback",
>  	"thp_collapse_alloc",
>  	"thp_collapse_alloc_failed",
> -	"thp_split",
> +	"thp_split_page",
> +	"thp_split_page_failed",
> +	"thp_split_pmd",
>  	"thp_zero_page_alloc",
>  	"thp_zero_page_alloc_failed",
>  #endif
>