Re: [PATCH v2 5/5] hugetlb: convert PageHugeFreed to HPageFreed flag

Oscar Salvador
2021-01-20T10:31:20Z

On Tue, Jan 19, 2021 at 05:30:49PM -0800, Mike Kravetz wrote:
> Use new hugetlb specific HPageFreed flag to replace the
> PageHugeFreed interfaces.
>
> Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>

Reviewed-by: Oscar Salvador <osalvador@suse.de>

> ---
> include/linux/hugetlb.h | 3 +++
> mm/hugetlb.c | 23 ++++-------------------
> 2 files changed, 7 insertions(+), 19 deletions(-)
>
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index ec329b9cc0fc..8fd0970cefdb 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -487,11 +487,13 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
> * allocator. Typically used for migration target pages when no pages
> * are available in the pool. The hugetlb free page path will
> * immediately free pages with this flag set to the buddy allocator.
> + * HPG_freed - Set when page is on the free lists.
> */
> enum hugetlb_page_flags {
> HPG_restore_reserve = 0,
> HPG_migratable,
> HPG_temporary,
> + HPG_freed,
> __NR_HPAGEFLAGS,
> };
>
> @@ -540,6 +542,7 @@ static inline void ClearHPage##uname(struct page *page) \
> HPAGEFLAG(RestoreReserve, restore_reserve)
> HPAGEFLAG(Migratable, migratable)
> HPAGEFLAG(Temporary, temporary)
> +HPAGEFLAG(Freed, freed)
>
> #ifdef CONFIG_HUGETLB_PAGE
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 0d2bfc2b6adc..d5a78aedbfda 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -79,21 +79,6 @@ DEFINE_SPINLOCK(hugetlb_lock);
> static int num_fault_mutexes;
> struct mutex *hugetlb_fault_mutex_table ____cacheline_aligned_in_smp;
>
> -static inline bool PageHugeFreed(struct page *head)
> -{
> - return page_private(head + 4) == -1UL;
> -}
> -
> -static inline void SetPageHugeFreed(struct page *head)
> -{
> - set_page_private(head + 4, -1UL);
> -}
> -
> -static inline void ClearPageHugeFreed(struct page *head)
> -{
> - set_page_private(head + 4, 0);
> -}
> -
> /* Forward declaration */
> static int hugetlb_acct_memory(struct hstate *h, long delta);
>
> @@ -1043,7 +1028,7 @@ static void enqueue_huge_page(struct hstate *h, struct page *page)
> list_move(&page->lru, &h->hugepage_freelists[nid]);
> h->free_huge_pages++;
> h->free_huge_pages_node[nid]++;
> - SetPageHugeFreed(page);
> + SetHPageFreed(page);
> }
>
> static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid)
> @@ -1060,7 +1045,7 @@ static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid)
>
> list_move(&page->lru, &h->hugepage_activelist);
> set_page_refcounted(page);
> - ClearPageHugeFreed(page);
> + ClearHPageFreed(page);
> h->free_huge_pages--;
> h->free_huge_pages_node[nid]--;
> return page;
> @@ -1474,7 +1459,7 @@ static void prep_new_huge_page(struct hstate *h, struct page *page, int nid)
> spin_lock(&hugetlb_lock);
> h->nr_huge_pages++;
> h->nr_huge_pages_node[nid]++;
> - ClearPageHugeFreed(page);
> + ClearHPageFreed(page);
> spin_unlock(&hugetlb_lock);
> }
>
> @@ -1747,7 +1732,7 @@ int dissolve_free_huge_page(struct page *page)
> * We should make sure that the page is already on the free list
> * when it is dissolved.
> */
> - if (unlikely(!PageHugeFreed(head))) {
> + if (unlikely(!HPageFreed(head))) {
> rc = -EAGAIN;
> goto out;
> }
> --
> 2.29.2
>
>

--
Oscar Salvador
SUSE L3