linux-kernel - [PATCH net-next v7 03/15] mm: page_frag: use free_unref

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Message-ID: <20240607123819.40694-4-linyunsheng@huawei.com>
Date: Fri, 7 Jun 2024 20:38:06 +0800
From: Yunsheng Lin <linyunsheng@...wei.com>
To: <davem@...emloft.net>, <kuba@...nel.org>, <pabeni@...hat.com>
CC: <netdev@...r.kernel.org>, <linux-kernel@...r.kernel.org>, Yunsheng Lin
	<linyunsheng@...wei.com>, Alexander Duyck <alexander.duyck@...il.com>, Andrew
 Morton <akpm@...ux-foundation.org>, <linux-mm@...ck.org>
Subject: [PATCH net-next v7 03/15] mm: page_frag: use free_unref_page() to free page fragment

free_the_page() used by page_frag call free_unref_page() or
__free_pages_ok() depending on pcp_allowed_order(), as the
max order of page allocated for page_frag is 3, the checking
in pcp_allowed_order() is unnecessary.

So call free_unref_page() directly to free a page_frag page
to aovid the unnecessary checking.

As the free_the_page() is a static function in page_alloc.c,
using the new one also allow moving page_frag related code
to a new file in the next patch.

CC: Alexander Duyck <alexander.duyck@...il.com>
Signed-off-by: Yunsheng Lin <linyunsheng@...wei.com>
---
 mm/page_alloc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2e22ce5675ca..0511c30bc265 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4781,6 +4781,9 @@ static struct page *__page_frag_cache_refill(struct page_frag_cache *nc,
 	gfp_t gfp = gfp_mask;
 
 #if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
+	/* Ensure free_unref_page() can be used to free the page fragment */
+	BUILD_BUG_ON(PAGE_FRAG_CACHE_MAX_ORDER > PAGE_ALLOC_COSTLY_ORDER);
+
 	gfp_mask = (gfp_mask & ~__GFP_DIRECT_RECLAIM) |  __GFP_COMP |
 		   __GFP_NOWARN | __GFP_NORETRY | __GFP_NOMEMALLOC;
 	page = alloc_pages_node(NUMA_NO_NODE, gfp_mask,
-- 
2.33.0