From 2fa8085fc6daa255c591e754f66ba98035b797c3 Mon Sep 17 00:00:00 2001
From: Wright Feng <wright.feng@cypress.com>
Date: Wed, 24 Jun 2020 04:16:08 -0500
Subject: [PATCH] brcmfmac: set pacing shift before transmitting skb to bus
Git-commit: 2fa8085fc6daa255c591e754f66ba98035b797c3
Patch-mainline: v5.9-rc1
References: jsc#SLE-13430
Linux 3.6 introduces TSQ which has a per socket threshold for TCP Tx
packet to reduce latency. In flow control mode, host driver enqueues skb
in hanger and TCP doesn't push new skb frees until host frees the skb when
receiving fwstatus event. So set pacing shift 8 to send them as a single
large aggregate frame to the bus layer.
43455 TX TCP throughput in different FC modes on Linux 5.4.18
sk_pacing_shift : Throughput (fcmode=0)
10: 245 Mbps 9: 245 Mbps 8: 246 Mbps 7: 246 Mbps
sk_pacing_shift : Throughput (fcmode=1)
10: 182 Mbps 9: 197 Mbps 8: 206 Mbps 7: 207 Mbps
sk_pacing_shift : Throughput (fcmode=2)
10: 180 Mbps 9: 197 Mbps 8: 206 Mbps 7: 207 Mbps
Signed-off-by: Wright Feng <wright.feng@cypress.com>
Signed-off-by: Chi-hsien Lin <chi-hsien.lin@cypress.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200624091608.25154-3-wright.feng@cypress.com
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
index c88655acc78c..f89010a81ffb 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
@@ -352,6 +352,9 @@ static netdev_tx_t brcmf_netdev_start_xmit(struct sk_buff *skb,
if ((skb->priority == 0) || (skb->priority > 7))
skb->priority = cfg80211_classify8021d(skb, NULL);
+ /* set pacing shift for packet aggregation */
+ sk_pacing_shift_update(skb->sk, 8);
+
ret = brcmf_proto_tx_queue_data(drvr, ifp->ifidx, skb);
if (ret < 0)
brcmf_txfinalize(ifp, skb, false);
--
2.16.4