From e830dee528d6da5bf3da5304d7686637ea5bec7d Mon Sep 17 00:00:00 2001 From: Alexander Lobakin Date: Fri, 16 Jul 2021 17:19:16 +0800 Subject: [PATCH] net: introduce common dev_page_is_reusable() mainline inclusion from mainline-v5.12-rc1-dontuse commit bc38f30f8dbce0afb8af05d917bee084b1329418 category: feature bugzilla: 173966 CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=bc38f30f8dbce0afb8af05d917bee084b1329418 ---------------------------------------------------------------------- A bunch of drivers test the page before reusing/recycling for two common conditions: - if a page was allocated under memory pressure (pfmemalloc page); - if a page was allocated at a distant memory node (to exclude slowdowns). Introduce a new common inline for doing this, with likely() already folded inside to make driver code a bit simpler. Suggested-by: David Rientjes Suggested-by: Jakub Kicinski Cc: John Hubbard Signed-off-by: Alexander Lobakin Reviewed-by: Jesse Brandeburg Acked-by: David Rientjes Signed-off-by: Jakub Kicinski Reviewed-by: Yongxin Li Signed-off-by: Zheng Zengkai --- include/linux/skbuff.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 345944698dd4..b86e3dca2955 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -2922,6 +2922,22 @@ static inline struct page *dev_alloc_page(void) return dev_alloc_pages(0); } +/** + * dev_page_is_reusable - check whether a page can be reused for network Rx + * @page: the page to test + * + * A page shouldn't be considered for reusing/recycling if it was allocated + * under memory pressure or at a distant memory node. + * + * Returns false if this page should be returned to page allocator, true + * otherwise. + */ +static inline bool dev_page_is_reusable(const struct page *page) +{ + return likely(page_to_nid(page) == numa_mem_id() && + !page_is_pfmemalloc(page)); +} + /** * skb_propagate_pfmemalloc - Propagate pfmemalloc if skb is allocated after RX page * @page: The page that was allocated from skb_alloc_page -- GitLab