[PATCH] wifi: ath9k: adjust ath9k_rx_prepare() and simplify ath9k_rx_tasklet()

[PATCH] wifi: ath9k: adjust ath9k_rx_prepare() and simplify ath9k_rx_tasklet()

[Dmitry Antipov]

Adjust 'ath9k_rx_prepare()' to fill skb control buffer directly rather
than using temporary 'struct ieee80211_rx_status' in 'ath9k_rx_tasklet()',
thus making both temporary and 'memcpy()' redundant. Compile tested only.

Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
---
 drivers/net/wireless/ath/ath9k/htc_drv_txrx.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
index ce9c04e418b8..acbcb37150eb 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
@@ -969,13 +969,12 @@ static void rx_status_htc_to_ath(struct ath_rx_status *rx_stats,
 }
 
 static bool ath9k_rx_prepare(struct ath9k_htc_priv *priv,
-			     struct ath9k_htc_rxbuf *rxbuf,
-			     struct ieee80211_rx_status *rx_status)
-
+			     struct ath9k_htc_rxbuf *rxbuf)
 {
 	struct ieee80211_hdr *hdr;
 	struct ieee80211_hw *hw = priv->hw;
 	struct sk_buff *skb = rxbuf->skb;
+	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
 	struct ath_common *common = ath9k_hw_common(priv->ah);
 	struct ath_hw *ah = common->ah;
 	struct ath_htc_rx_status *rxstatus;
@@ -1081,7 +1080,6 @@ void ath9k_rx_tasklet(struct tasklet_struct *t)
 {
 	struct ath9k_htc_priv *priv = from_tasklet(priv, t, rx_tasklet);
 	struct ath9k_htc_rxbuf *rxbuf = NULL, *tmp_buf = NULL;
-	struct ieee80211_rx_status rx_status;
 	struct sk_buff *skb;
 	unsigned long flags;
 	struct ieee80211_hdr *hdr;
@@ -1103,13 +1101,11 @@ void ath9k_rx_tasklet(struct tasklet_struct *t)
 		if (!rxbuf->skb)
 			goto requeue;
 
-		if (!ath9k_rx_prepare(priv, rxbuf, &rx_status)) {
+		if (!ath9k_rx_prepare(priv, rxbuf)) {
 			dev_kfree_skb_any(rxbuf->skb);
 			goto requeue;
 		}
 
-		memcpy(IEEE80211_SKB_RXCB(rxbuf->skb), &rx_status,
-		       sizeof(struct ieee80211_rx_status));
 		skb = rxbuf->skb;
 		hdr = (struct ieee80211_hdr *) skb->data;
 
-- 
2.48.1

Re: [PATCH] wifi: ath9k: adjust ath9k_rx_prepare() and simplify ath9k_rx_tasklet()

[Toke Høiland-Jørgensen]

Dmitry Antipov <dmantipov@yandex.ru> writes:

> Adjust 'ath9k_rx_prepare()' to fill skb control buffer directly rather
> than using temporary 'struct ieee80211_rx_status' in 'ath9k_rx_tasklet()',
> thus making both temporary and 'memcpy()' redundant. Compile tested
> only.

Hmm, so the existing code follows the "perform checks, then write data"
pattern, which is generally good practice. I don't think saving a
48-byte memcpy() is worth it to deviate from this pattern. Certainly not
without testing :)

-Toke