Re: [PATCH v5 6/6] mm: shmem: add mTHP counters for anonymous shmem

[Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>]

On 2024/6/11 18:11, Baolin Wang wrote:
> Add mTHP counters for anonymous shmem.
>
> Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
> ---
>   include/linux/huge_mm.h |  3 +++
>   mm/huge_memory.c        |  6 ++++++
>   mm/shmem.c              | 18 +++++++++++++++---
>   3 files changed, 24 insertions(+), 3 deletions(-)
>
> diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
> index 909cfc67521d..212cca384d7e 100644
> --- a/include/linux/huge_mm.h
> +++ b/include/linux/huge_mm.h
> @@ -281,6 +281,9 @@ enum mthp_stat_item {
>   	MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE,
>   	MTHP_STAT_SWPOUT,
>   	MTHP_STAT_SWPOUT_FALLBACK,
> +	MTHP_STAT_FILE_ALLOC,
> +	MTHP_STAT_FILE_FALLBACK,
> +	MTHP_STAT_FILE_FALLBACK_CHARGE,
>   	__MTHP_STAT_COUNT
>   };
>   
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index 1360a1903b66..3fbcd77f5957 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -555,6 +555,9 @@ DEFINE_MTHP_STAT_ATTR(anon_fault_fallback, MTHP_STAT_ANON_FAULT_FALLBACK);
>   DEFINE_MTHP_STAT_ATTR(anon_fault_fallback_charge, MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE);
>   DEFINE_MTHP_STAT_ATTR(swpout, MTHP_STAT_SWPOUT);
>   DEFINE_MTHP_STAT_ATTR(swpout_fallback, MTHP_STAT_SWPOUT_FALLBACK);
> +DEFINE_MTHP_STAT_ATTR(file_alloc, MTHP_STAT_FILE_ALLOC);
> +DEFINE_MTHP_STAT_ATTR(file_fallback, MTHP_STAT_FILE_FALLBACK);
> +DEFINE_MTHP_STAT_ATTR(file_fallback_charge, MTHP_STAT_FILE_FALLBACK_CHARGE);
>   
>   static struct attribute *stats_attrs[] = {
>   	&anon_fault_alloc_attr.attr,
> @@ -562,6 +565,9 @@ static struct attribute *stats_attrs[] = {
>   	&anon_fault_fallback_charge_attr.attr,
>   	&swpout_attr.attr,
>   	&swpout_fallback_attr.attr,
> +	&file_alloc_attr.attr,
> +	&file_fallback_attr.attr,
> +	&file_fallback_charge_attr.attr,
>   	NULL,
>   };
>   
> diff --git a/mm/shmem.c b/mm/shmem.c
> index f5469c357be6..99bd3c34f0fb 100644
> --- a/mm/shmem.c
> +++ b/mm/shmem.c
> @@ -1773,6 +1773,9 @@ static struct folio *shmem_alloc_and_add_folio(struct vm_fault *vmf,
>   
>   			if (pages == HPAGE_PMD_NR)
>   				count_vm_event(THP_FILE_FALLBACK);
> +#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> +			count_mthp_stat(order, MTHP_STAT_FILE_FALLBACK);
> +#endif
>   			order = next_order(&suitable_orders, order);
>   		}
>   	} else {
> @@ -1792,9 +1795,15 @@ static struct folio *shmem_alloc_and_add_folio(struct vm_fault *vmf,
>   		if (xa_find(&mapping->i_pages, &index,
>   				index + pages - 1, XA_PRESENT)) {
>   			error = -EEXIST;
> -		} else if (pages == HPAGE_PMD_NR) {
> -			count_vm_event(THP_FILE_FALLBACK);
> -			count_vm_event(THP_FILE_FALLBACK_CHARGE);
> +		} else if (pages > 1) {
> +			if (pages == HPAGE_PMD_NR) {
> +				count_vm_event(THP_FILE_FALLBACK);
> +				count_vm_event(THP_FILE_FALLBACK_CHARGE);
> +			}
> +#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> +			count_mthp_stat(folio_order(folio), MTHP_STAT_FILE_FALLBACK);
> +			count_mthp_stat(folio_order(folio), MTHP_STAT_FILE_FALLBACK_CHARGE);

pages > 1, we have correct order, count_mthp_stat(order, MTHP_XXX) ?

> +#endif
>   		}
>   		goto unlock;
>   	}
> @@ -2168,6 +2177,9 @@ static int shmem_get_folio_gfp(struct inode *inode, pgoff_t index,
>   		if (!IS_ERR(folio)) {
>   			if (folio_test_pmd_mappable(folio))
>   				count_vm_event(THP_FILE_ALLOC);
> +#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> +			count_mthp_stat(folio_order(folio), MTHP_STAT_FILE_ALLOC);
> +#endif
>   			goto alloced;
>   		}
>   		if (PTR_ERR(folio) == -EEXIST)