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From:   Ziyang Xuan <william.xuanziyang@huawei.com>
To:     <socketcan@hartkopp.net>, <mkl@pengutronix.de>,
        <linux-can@vger.kernel.org>, <netdev@vger.kernel.org>
CC:     <davem@davemloft.net>, <edumazet@google.com>, <kuba@kernel.org>,
        <pabeni@redhat.com>, <linux-kernel@vger.kernel.org>
Subject: [PATCH net-next 2/2] can: raw: use guard clause to optimize nesting in raw_rcv()
Date:   Sat, 27 Aug 2022 15:20:11 +0800
Message-ID: <0170ad1f07dbe838965df4274fce950980fa9d1f.1661584485.git.william.xuanziyang@huawei.com>
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References: <cover.1661584485.git.william.xuanziyang@huawei.com>
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We can use guard clause to optimize nesting codes like
if (condition) { ... } else { return; } in raw_rcv();

Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
---
 net/can/raw.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/net/can/raw.c b/net/can/raw.c
index 9ae7c4206b9a..e7dfa3584e29 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -136,14 +136,13 @@ static void raw_rcv(struct sk_buff *oskb, void *data)
 	/* eliminate multiple filter matches for the same skb */
 	if (this_cpu_ptr(ro->uniq)->skb == oskb &&
 	    this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) {
-		if (ro->join_filters) {
-			this_cpu_inc(ro->uniq->join_rx_count);
-			/* drop frame until all enabled filters matched */
-			if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count)
-				return;
-		} else {
+		if (!ro->join_filters)
+			return;
+
+		this_cpu_inc(ro->uniq->join_rx_count);
+		/* drop frame until all enabled filters matched */
+		if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count)
 			return;
-		}
 	} else {
 		this_cpu_ptr(ro->uniq)->skb = oskb;
 		this_cpu_ptr(ro->uniq)->skbcnt = can_skb_prv(oskb)->skbcnt;
-- 
2.25.1