Linux 3.6 introduces TSQ which has a per socket threshold for TCP Tx packets to reduce latency. In fcmode 1 and fcmode 2, host driver enqueues skb in hanger and TCP doesn't push new skb until host frees the skb when receiving fwstatus event. So using skb_orphan before sending skb to bus will make the skb removing the ownership of socket. With this patch, we are able to get better throughput in fcmode 1 and fcmode 2.
Tested 43455 TCP throughput in 20 MHz bandwidth with / without this patch. fcmode 0: 59.5 / 59.6 (mbps) fcmode 1: 59.3 / 23.4 (mbps) fcmode 2: 59.6 / 21.5 (mbps) Signed-off-by: Wright Feng <[email protected]> --- drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c index b2e1ab5..519b25d 100644 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c @@ -2298,6 +2298,7 @@ static uint brcmf_sdio_sendfromq(struct brcmf_sdio *bus, uint maxframes) &prec_out); if (pkt == NULL) break; + skb_orphan(pkt); __skb_queue_tail(&pktq, pkt); } spin_unlock_bh(&bus->txq_lock); -- 1.9.1
