[PATCH net-next 5/7] skbuff: keep track of pp page when __skb_frag_ref() is called

@@ -2503,7 +2503,7 @@ static void skb_put_frags(struct sk_buff *skb, unsigned int hdr_space,
 
 		if (length == 0) {
 			/* don't need this page */
-			__skb_frag_unref(frag, false);
+			__skb_frag_unref(frag);
 			--skb_shinfo(skb)->nr_frags;
 		} else {
 			size = min(length, (unsigned) PAGE_SIZE);

@@ -526,7 +526,7 @@ static int mlx4_en_complete_rx_desc(struct mlx4_en_priv *priv,
 fail:
 	while (nr > 0) {
 		nr--;
-		__skb_frag_unref(skb_shinfo(skb)->frags + nr, false);
+		__skb_frag_unref(skb_shinfo(skb)->frags + nr);
 	}
 	return 0;
 }

@@ -3073,7 +3073,16 @@ static inline struct page *skb_frag_page(const skb_frag_t *frag)
  */
 static inline void __skb_frag_ref(skb_frag_t *frag)
 {
-	get_page(skb_frag_page(frag));
+	struct page *page = skb_frag_page(frag);
+
+#ifdef CONFIG_PAGE_POOL
+	if (page_pool_is_pp_page(page)) {
+		page_pool_atomic_inc_frag_count(page);
+		return;
+	}
+#endif
+
+	get_page(page);
 }
 
 /**

@@ -3091,18 +3100,19 @@ static inline void skb_frag_ref(struct sk_buff *skb, int f)
 /**
  * __skb_frag_unref - release a reference on a paged fragment.
  * @frag: the paged fragment
- * @recycle: recycle the page if allocated via page_pool
  *
  * Releases a reference on the paged fragment @frag
  * or recycles the page via the page_pool API.
  */
-static inline void __skb_frag_unref(skb_frag_t *frag, bool recycle)
+static inline void __skb_frag_unref(skb_frag_t *frag)
 {
 	struct page *page = skb_frag_page(frag);
 
 #ifdef CONFIG_PAGE_POOL
-	if (recycle && page_pool_return_skb_page(page))
+	if (page_pool_is_pp_page(page)) {
+		page_pool_return_skb_page(page);
 		return;
+	}
 #endif
 	put_page(page);
 }

@@ -3116,7 +3126,7 @@ static inline void __skb_frag_unref(skb_frag_t *frag, bool recycle)
  */
 static inline void skb_frag_unref(struct sk_buff *skb, int f)
 {
-	__skb_frag_unref(&skb_shinfo(skb)->frags[f], skb->pp_recycle);
+	__skb_frag_unref(&skb_shinfo(skb)->frags[f]);
 }
 
 /**

@@ -4720,9 +4730,17 @@ static inline void skb_mark_for_recycle(struct sk_buff *skb)
 
 static inline bool skb_pp_recycle(struct sk_buff *skb, void *data)
 {
+	struct page *page;
+
 	if (!IS_ENABLED(CONFIG_PAGE_POOL) || !skb->pp_recycle)
 		return false;
-	return page_pool_return_skb_page(virt_to_head_page(data));
+
+	page = virt_to_head_page(data);
+	if (!page_pool_is_pp_page(page))
+		return false;
+
+	page_pool_return_skb_page(page);
+	return true;
 }
 
 #endif	/* __KERNEL__ */

@@ -164,7 +164,7 @@ inline enum dma_data_direction page_pool_get_dma_dir(struct page_pool *pool)
 	return pool->p.dma_dir;
 }
 
-bool page_pool_return_skb_page(struct page *page);
+void page_pool_return_skb_page(struct page *page);
 
 struct page_pool *page_pool_create(const struct page_pool_params *params);
 

@@ -231,6 +231,23 @@ static inline void page_pool_set_frag_count(struct page *page, long nr)
 	atomic_long_set(&page->pp_frag_count, nr);
 }
 
+static inline void page_pool_atomic_inc_frag_count(struct page *page)
+{
+	atomic_long_inc(&page->pp_frag_count);
+}
+
+static inline bool page_pool_is_pp_page(struct page *page)
+{
+	/* page->pp_magic is OR'ed with PP_SIGNATURE after the allocation
+	 * in order to preserve any existing bits, such as bit 0 for the
+	 * head page of compound page and bit 1 for pfmemalloc page, so
+	 * mask those bits for freeing side when doing below checking,
+	 * and page_is_pfmemalloc() is checked in __page_pool_put_page()
+	 * to avoid recycling the pfmemalloc page.
+	 */
+	return (page->pp_magic & ~0x3UL) == PP_SIGNATURE;
+}
+
 static inline long page_pool_atomic_sub_frag_count_return(struct page *page,
 							  long nr)
 {

@@ -738,20 +738,10 @@ void page_pool_update_nid(struct page_pool *pool, int new_nid)
 }
 EXPORT_SYMBOL(page_pool_update_nid);
 
-bool page_pool_return_skb_page(struct page *page)
+void page_pool_return_skb_page(struct page *page)
 {
 	struct page_pool *pp;
 
-	/* page->pp_magic is OR'ed with PP_SIGNATURE after the allocation
-	 * in order to preserve any existing bits, such as bit 0 for the
-	 * head page of compound page and bit 1 for pfmemalloc page, so
-	 * mask those bits for freeing side when doing below checking,
-	 * and page_is_pfmemalloc() is checked in __page_pool_put_page()
-	 * to avoid recycling the pfmemalloc page.
-	 */
-	if (unlikely((page->pp_magic & ~0x3UL) != PP_SIGNATURE))
-		return false;
-
 	pp = page->pp;
 
 	/* Driver set this to memory recycling info. Reset it on recycle.

@@ -760,7 +750,5 @@ bool page_pool_return_skb_page(struct page *page)
 	 * 'flipped' fragment being in use or not.
 	 */
 	page_pool_put_full_page(pp, page, false);
-
-	return true;
 }
 EXPORT_SYMBOL(page_pool_return_skb_page);

@@ -668,7 +668,7 @@ static void skb_release_data(struct sk_buff *skb)
 	skb_zcopy_clear(skb, true);
 
 	for (i = 0; i < shinfo->nr_frags; i++)
-		__skb_frag_unref(&shinfo->frags[i], skb->pp_recycle);
+		__skb_frag_unref(&shinfo->frags[i]);
 
 	if (shinfo->frag_list)
 		kfree_skb_list(shinfo->frag_list);

@@ -3563,7 +3563,7 @@ int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen)
 		fragto = &skb_shinfo(tgt)->frags[merge];
 
 		skb_frag_size_add(fragto, skb_frag_size(fragfrom));
-		__skb_frag_unref(fragfrom, skb->pp_recycle);
+		__skb_frag_unref(fragfrom);
 	}
 
 	/* Reposition in the original skb */

@@ -128,7 +128,7 @@ static void destroy_record(struct tls_record_info *record)
 	int i;
 
 	for (i = 0; i < record->num_frags; i++)
-		__skb_frag_unref(&record->frags[i], false);
+		__skb_frag_unref(&record->frags[i]);
 	kfree(record);
 }