Bluetooth: Controller: Fix free rx buffer MFIFO enqueue

cvinayak · galak · commit e43afd10f793 · 2021-06-30T08:24:55.000-05:00
Replace the post decrement in loop's conditional into
explicit decrement inside the loop so as to avoid
decrementing the maximum count without enqueueing free rx
buffers into the free rx buffer MFIFO.

Signed-off-by: Vinayak Kariappa Chettimada &lt;vich@nordicsemi.no&gt;
diff --git a/subsys/bluetooth/controller/ll_sw/ull.c b/subsys/bluetooth/controller/ll_sw/ull.c
@@ -1997,7 +1997,7 @@ static inline void rx_alloc(uint8_t max)
 		max = mem_link_rx.quota_pdu;
 	}
 
-	while ((max--) && MFIFO_ENQUEUE_IDX_GET(pdu_rx_free, &idx)) {
+	while (max && MFIFO_ENQUEUE_IDX_GET(pdu_rx_free, &idx)) {
 		memq_link_t *link;
 		struct node_rx_hdr *rx;
 
@@ -2017,6 +2017,8 @@ static inline void rx_alloc(uint8_t max)
 		MFIFO_BY_IDX_ENQUEUE(pdu_rx_free, idx, rx);
 
 		ll_rx_link_inc_quota(-1);
+
+		max--;
 	}
 
 #if defined(CONFIG_BT_CONN)

Original file line number	Diff line number	Diff line change
`@@ -1997,7 +1997,7 @@ static inline void rx_alloc(uint8_t max)`
`1997`	`1997`	`max = mem_link_rx.quota_pdu;`
`1998`	`1998`	`}`
`1999`	`1999`
`2000`		`- while ((max--) && MFIFO_ENQUEUE_IDX_GET(pdu_rx_free, &idx)) {`
	`2000`	`+ while (max && MFIFO_ENQUEUE_IDX_GET(pdu_rx_free, &idx)) {`
`2001`	`2001`	`memq_link_t *link;`
`2002`	`2002`	`struct node_rx_hdr *rx;`
`2003`	`2003`
`@@ -2017,6 +2017,8 @@ static inline void rx_alloc(uint8_t max)`
`2017`	`2017`	`MFIFO_BY_IDX_ENQUEUE(pdu_rx_free, idx, rx);`
`2018`	`2018`
`2019`	`2019`	`ll_rx_link_inc_quota(-1);`
	`2020`	`+`
	`2021`	`+ max--;`
`2020`	`2022`	`}`
`2021`	`2023`
`2022`	`2024`	`#if defined(CONFIG_BT_CONN)`