From: Eric Dumazet <edumazet@google.com>
Date: Tue, 15 Nov 2022 09:11:01 +0000 (+0000)
Subject: net: __sock_gen_cookie() cleanup
X-Git-Tag: v6.6.7~3913^2~205^2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4ebf802cf1c6a87fd14e7936728c99e18d7ba794;p=platform%2Fkernel%2Flinux-starfive.git

net: __sock_gen_cookie() cleanup

Adopt atomic64_try_cmpxchg() and remove the loop,
to make the intent more obvious.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/core/sock_diag.c b/net/core/sock_diag.c
index f7cf74c..b11593c 100644
--- a/net/core/sock_diag.c
+++ b/net/core/sock_diag.c
@@ -25,14 +25,14 @@ DEFINE_COOKIE(sock_cookie);
 
 u64 __sock_gen_cookie(struct sock *sk)
 {
-	while (1) {
-		u64 res = atomic64_read(&sk->sk_cookie);
+	u64 res = atomic64_read(&sk->sk_cookie);
 
-		if (res)
-			return res;
-		res = gen_cookie_next(&sock_cookie);
-		atomic64_cmpxchg(&sk->sk_cookie, 0, res);
+	if (!res) {
+		u64 new = gen_cookie_next(&sock_cookie);
+
+		atomic64_try_cmpxchg(&sk->sk_cookie, &res, new);
 	}
+	return res;
 }
 
 int sock_diag_check_cookie(struct sock *sk, const __u32 *cookie)