Re: [PATCH v9 09/15] mm: Remove locking mf_mutex in is_raw_hwpoison_page_in_hugepage()

[Miaohe Lin <linmiaohe@huawei.com>]

On 2026/8/6 5:05, Matthew Wilcox (Oracle) wrote:
> Sleeping in this kind of predicate is unexpected.  Add a new spinlock
> to protect access to the list, and turn it into a normal singly linked
> list now that it doesn't need to be a lockless list.
> 
> Rename is_raw_hwpoison_page_in_hugepage() to hugetlb_page_hwpoison()
> and make it take the folio (since the callers naturally have the folio).
> Also remove the handling of non-hugetlb folios and make the arguments
> const.
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> Reviewed-by: Jane Chu <jane.chu@oracle.com>
> Reviewed-by: Gregory Price (Meta) <gourry@gourry.net>
> ---
>  fs/hugetlbfs/inode.c     |   4 +-
>  include/linux/hugetlb.h  |   5 +-
>  include/linux/mm_types.h |   4 +-
>  mm/memory-failure.c      | 101 ++++++++++++++++++++++-----------------
>  4 files changed, 61 insertions(+), 53 deletions(-)
> 
> diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
> index fbac554886c3..dbca3f713bbf 100644
> --- a/fs/hugetlbfs/inode.c
> +++ b/fs/hugetlbfs/inode.c
> @@ -198,7 +198,7 @@ static size_t adjust_range_hwpoison(struct folio *folio, size_t offset,
>  	struct page *page = folio_page(folio, offset / PAGE_SIZE);
>  	size_t safe_bytes;
>  
> -	if (is_raw_hwpoison_page_in_hugepage(page))
> +	if (hugetlb_page_hwpoison(folio, page))
>  		return 0;
>  	/* Safe to read the remaining bytes in this page. */
>  	safe_bytes = PAGE_SIZE - (offset % PAGE_SIZE);
> @@ -206,7 +206,7 @@ static size_t adjust_range_hwpoison(struct folio *folio, size_t offset,
>  
>  	/* Check each remaining page as long as we are not done yet. */
>  	for (; safe_bytes < bytes; safe_bytes += PAGE_SIZE, page++)
> -		if (is_raw_hwpoison_page_in_hugepage(page))
> +		if (hugetlb_page_hwpoison(folio, page))
>  			break;
>  
>  	return min(safe_bytes, bytes);
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index e200c93088bc..ec604cee8d22 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -1088,10 +1088,7 @@ void hugetlb_register_node(struct node *node);
>  void hugetlb_unregister_node(struct node *node);
>  #endif
>  
> -/*
> - * Check if a given raw @page in a hugepage is HWPOISON.
> - */
> -bool is_raw_hwpoison_page_in_hugepage(struct page *page);
> +bool hugetlb_page_hwpoison(const struct folio *folio, const struct page *page);
>  
>  static inline unsigned long huge_page_mask_align(struct file *file)
>  {
> diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
> index b18c2b2e7d2c..86a2d0fee557 100644
> --- a/include/linux/mm_types.h
> +++ b/include/linux/mm_types.h
> @@ -387,7 +387,7 @@ typedef unsigned short mm_id_t;
>   * @_hugetlb_subpool: Do not use directly, use accessor in hugetlb.h.
>   * @_hugetlb_cgroup: Do not use directly, use accessor in hugetlb_cgroup.h.
>   * @_hugetlb_cgroup_rsvd: Do not use directly, use accessor in hugetlb_cgroup.h.
> - * @_hugetlb_hwpoison: Do not use directly, call raw_hwp_list_head().
> + * @hugetlb_hwpoison: List of pages with hwpoison.
>   * @_deferred_list: Folios to be split under memory pressure.
>   * @_unused_slab_obj_exts: Placeholder to match obj_exts in struct slab.
>   *
> @@ -499,7 +499,7 @@ struct folio {
>  			void *_hugetlb_subpool;
>  			void *_hugetlb_cgroup;
>  			void *_hugetlb_cgroup_rsvd;
> -			void *_hugetlb_hwpoison;
> +			struct hwp_page *hugetlb_hwpoison;

It might be better to rename it as _hugetlb_hwpoison, i.e. with "_" prefix,
to keep the naming style consistant. Anyway:

Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>

Thanks.
.