net: page_pool: factor out page_pool recycle check

The check is duplicated in 2 places, factor it out into a common helper.

Signed-off-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Link: https://lore.kernel.org/r/20240308204500.1112858-1-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: mina

net/core/page_pool.c

@@ -657,6 +657,11 @@ static bool page_pool_recycle_in_cache(struct page *page,
 	return true;
 }
 
+static bool __page_pool_page_can_be_recycled(const struct page *page)
+{
+	return page_ref_count(page) == 1 && !page_is_pfmemalloc(page);
+}
+
 /* If the page refcnt == 1, this will try to recycle the page.
  * if PP_FLAG_DMA_SYNC_DEV is set, we'll try to sync the DMA area for
  * the configured size min(dma_sync_size, pool->max_len).
@@ -678,7 +683,7 @@ __page_pool_put_page(struct page_pool *pool, struct page *page,
 	 * page is NOT reusable when allocated when system is under
 	 * some pressure. (page_is_pfmemalloc)
 	 */
-	if (likely(page_ref_count(page) == 1 && !page_is_pfmemalloc(page))) {
+	if (likely(__page_pool_page_can_be_recycled(page))) {
 		/* Read barrier done in page_ref_count / READ_ONCE */
 
 		if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV)
@@ -793,7 +798,7 @@ static struct page *page_pool_drain_frag(struct page_pool *pool,
 	if (likely(page_pool_unref_page(page, drain_count)))
 		return NULL;
 
-	if (page_ref_count(page) == 1 && !page_is_pfmemalloc(page)) {
+	if (__page_pool_page_can_be_recycled(page)) {
 		if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV)
 			page_pool_dma_sync_for_device(pool, page, -1);