Re: [PATCH 5/6] mm: Constify get_pfnblock_flags_mask and get_pfnblock_migratetype
From: Anshuman Khandual
Date: Mon Apr 26 2021 - 23:31:28 EST
On 4/17/21 4:45 AM, Matthew Wilcox (Oracle) wrote:
> The struct page is not modified by these routines, so it can be marked
> const.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> ---
> include/linux/pageblock-flags.h | 2 +-
> mm/page_alloc.c | 13 +++++++------
> 2 files changed, 8 insertions(+), 7 deletions(-)
>
> diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h
> index fff52ad370c1..973fd731a520 100644
> --- a/include/linux/pageblock-flags.h
> +++ b/include/linux/pageblock-flags.h
> @@ -54,7 +54,7 @@ extern unsigned int pageblock_order;
> /* Forward declaration */
> struct page;
>
> -unsigned long get_pfnblock_flags_mask(struct page *page,
> +unsigned long get_pfnblock_flags_mask(const struct page *page,
> unsigned long pfn,
> unsigned long mask);
>
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 0152670c6f04..4be2179eedd5 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -474,7 +474,7 @@ static inline bool defer_init(int nid, unsigned long pfn, unsigned long end_pfn)
> #endif
>
> /* Return a pointer to the bitmap storing bits affecting a block of pages */
> -static inline unsigned long *get_pageblock_bitmap(struct page *page,
> +static inline unsigned long *get_pageblock_bitmap(const struct page *page,
> unsigned long pfn)
> {
> #ifdef CONFIG_SPARSEMEM
> @@ -484,7 +484,7 @@ static inline unsigned long *get_pageblock_bitmap(struct page *page,
> #endif /* CONFIG_SPARSEMEM */
> }
>
> -static inline int pfn_to_bitidx(struct page *page, unsigned long pfn)
> +static inline int pfn_to_bitidx(const struct page *page, unsigned long pfn)
> {
> #ifdef CONFIG_SPARSEMEM
> pfn &= (PAGES_PER_SECTION-1);
> @@ -495,7 +495,7 @@ static inline int pfn_to_bitidx(struct page *page, unsigned long pfn)
> }
>
> static __always_inline
> -unsigned long __get_pfnblock_flags_mask(struct page *page,
> +unsigned long __get_pfnblock_flags_mask(const struct page *page,
> unsigned long pfn,
> unsigned long mask)
> {
> @@ -520,13 +520,14 @@ unsigned long __get_pfnblock_flags_mask(struct page *page,
> *
> * Return: pageblock_bits flags
> */
> -unsigned long get_pfnblock_flags_mask(struct page *page, unsigned long pfn,
> - unsigned long mask)
> +unsigned long get_pfnblock_flags_mask(const struct page *page,
> + unsigned long pfn, unsigned long mask)
> {
> return __get_pfnblock_flags_mask(page, pfn, mask);
> }
>
> -static __always_inline int get_pfnblock_migratetype(struct page *page, unsigned long pfn)
> +static __always_inline int get_pfnblock_migratetype(const struct page *page,
> + unsigned long pfn)
> {
> return __get_pfnblock_flags_mask(page, pfn, MIGRATETYPE_MASK);
> }
>
Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>