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From: Kuan-Wei Chiu <visitorckw@gmail.com>
To: toke@toke.dk
Cc: jhs@mojatatu.com,
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	Kuan-Wei Chiu <visitorckw@gmail.com>
Subject: [PATCH net-next] net: sched: cake: Optimize number of calls to cake_heapify()
Date: Sun,  7 Apr 2024 07:55:32 +0800
Message-Id: <20240406235532.613696-1-visitorckw@gmail.com>
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Improve the max-heap construction process by reducing unnecessary
heapify operations. Specifically, adjust the starting condition from
n / 2 to n / 2 - 1 in the loop that iterates over all non-leaf
elements.

Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
---
 net/sched/sch_cake.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c
index edee926ccde8..2eabc4dc5b79 100644
--- a/net/sched/sch_cake.c
+++ b/net/sched/sch_cake.c
@@ -1512,7 +1512,7 @@ static unsigned int cake_drop(struct Qdisc *sch, struct sk_buff **to_free)
 	if (!q->overflow_timeout) {
 		int i;
 		/* Build fresh max-heap */
-		for (i = CAKE_MAX_TINS * CAKE_QUEUES / 2; i >= 0; i--)
+		for (i = CAKE_MAX_TINS * CAKE_QUEUES / 2 - 1; i >= 0; i--)
 			cake_heapify(q, i);
 	}
 	q->overflow_timeout = 65535;
-- 
2.34.1