net: introduce common dev_page_is_reusable()

mainline inclusion
from mainline-v5.12-rc1-dontuse
commit bc38f30f
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: NDavid Rientjes <rientjes@google.com>
Suggested-by: NJakub Kicinski <kuba@kernel.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: NAlexander Lobakin <alobakin@pm.me>
Reviewed-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
Reviewed-by: NYongxin Li <liyongxin1@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

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