linux-kernel - [PATCH net-next 2/2] page_pool: try direct bulk recycling

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Fri, 29 Mar 2024 17:55:07 +0100
From: Alexander Lobakin <aleksander.lobakin@...el.com>
To: "David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>,
	Paolo Abeni <pabeni@...hat.com>
Cc: Alexander Lobakin <aleksander.lobakin@...el.com>,
	Lorenzo Bianconi <lorenzo@...nel.org>,
	Toke Høiland-Jørgensen <toke@...hat.com>,
	nex.sw.ncis.osdt.itp.upstreaming@...el.com,
	netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH net-next 2/2] page_pool: try direct bulk recycling

Now that the checks for direct recycling possibility live inside the
Page Pool core, reuse them when performing bulk recycling.
page_pool_put_page_bulk() can be called from process context as well,
page_pool_napi_local() takes care of this at the very beginning.
Under high .ndo_xdp_xmit() traffic load, the win is 2-3% Pps assuming
the sending driver uses xdp_return_frame_bulk() on Tx completion.

Signed-off-by: Alexander Lobakin <aleksander.lobakin@...el.com>
---
 net/core/page_pool.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 9d56257e444b..4c175091fc0a 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -772,8 +772,11 @@ void page_pool_put_page_bulk(struct page_pool *pool, void **data,
 			     int count)
 {
 	int i, bulk_len = 0;
+	bool allow_direct;
 	bool in_softirq;
 
+	allow_direct = page_pool_napi_local(pool);
+
 	for (i = 0; i < count; i++) {
 		struct page *page = virt_to_head_page(data[i]);
 
@@ -781,13 +784,13 @@ void page_pool_put_page_bulk(struct page_pool *pool, void **data,
 		if (!page_pool_is_last_ref(page))
 			continue;
 
-		page = __page_pool_put_page(pool, page, -1, false);
+		page = __page_pool_put_page(pool, page, -1, allow_direct);
 		/* Approved for bulk recycling in ptr_ring cache */
 		if (page)
 			data[bulk_len++] = page;
 	}
 
-	if (unlikely(!bulk_len))
+	if (!bulk_len)
 		return;
 
 	/* Bulk producer into ptr_ring page_pool cache */
-- 
2.44.0