Re: [PATCH v2 02/14] mm/page_alloc: add helper for checking if check_pages_enabled

From: Vlastimil Babka
Date: Wed Mar 22 2023 - 07:38:42 EST


On 3/21/23 18:05, Mike Rapoport wrote:
> From: "Mike Rapoport (IBM)" <rppt@xxxxxxxxxx>
>
> Instead of duplicating long static_branch_enabled(&check_pages_enabled)
> wrap it in a helper function is_check_pages_enabled()
>
> Signed-off-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
> Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>

Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx>

> ---
> mm/page_alloc.c | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 87d760236dba..e1149d54d738 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -245,6 +245,11 @@ EXPORT_SYMBOL(init_on_free);
> /* perform sanity checks on struct pages being allocated or freed */
> static DEFINE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled);
>
> +static inline bool is_check_pages_enabled(void)
> +{
> + return static_branch_unlikely(&check_pages_enabled);
> +}
> +
> static bool _init_on_alloc_enabled_early __read_mostly
> = IS_ENABLED(CONFIG_INIT_ON_ALLOC_DEFAULT_ON);
> static int __init early_init_on_alloc(char *buf)
> @@ -1443,7 +1448,7 @@ static __always_inline bool free_pages_prepare(struct page *page,
> for (i = 1; i < (1 << order); i++) {
> if (compound)
> bad += free_tail_pages_check(page, page + i);
> - if (static_branch_unlikely(&check_pages_enabled)) {
> + if (is_check_pages_enabled()) {
> if (unlikely(free_page_is_bad(page + i))) {
> bad++;
> continue;
> @@ -1456,7 +1461,7 @@ static __always_inline bool free_pages_prepare(struct page *page,
> page->mapping = NULL;
> if (memcg_kmem_online() && PageMemcgKmem(page))
> __memcg_kmem_uncharge_page(page, order);
> - if (static_branch_unlikely(&check_pages_enabled)) {
> + if (is_check_pages_enabled()) {
> if (free_page_is_bad(page))
> bad++;
> if (bad)
> @@ -2366,7 +2371,7 @@ static int check_new_page(struct page *page)
>
> static inline bool check_new_pages(struct page *page, unsigned int order)
> {
> - if (static_branch_unlikely(&check_pages_enabled)) {
> + if (is_check_pages_enabled()) {
> for (int i = 0; i < (1 << order); i++) {
> struct page *p = page + i;
>