From: Liang Chen <liangchen.linux@gmail.com>
Date: Fri, 15 Dec 2023 03:30:09 +0000 (+0800)
Subject: page_pool: halve BIAS_MAX for multiple user references of a fragment
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=aaf153aecef1d1831d0d6d371d5c11cf02f0337e;p=linux.git

page_pool: halve BIAS_MAX for multiple user references of a fragment

Up to now, we were only subtracting from the number of used page fragments
to figure out when a page could be freed or recycled. A following patch
introduces support for multiple users referencing the same fragment. So
reduce the initial page fragments value to half to avoid overflowing.

Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com>
Reviewed-by: Mina Almasry <almarsymina@google.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index dd5a72533f2b9..4933762e5a6ba 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -28,7 +28,7 @@
 #define DEFER_TIME (msecs_to_jiffies(1000))
 #define DEFER_WARN_INTERVAL (60 * HZ)
 
-#define BIAS_MAX	LONG_MAX
+#define BIAS_MAX	(LONG_MAX >> 1)
 
 #ifdef CONFIG_PAGE_POOL_STATS
 /* alloc_stat_inc is intended to be used in softirq context */