From 4ae0169fd1b3c792b66be58995b7e6b629919ecf Mon Sep 17 00:00:00 2001 From: Jose Abreu Date: Fri, 18 May 2018 14:55:59 +0100 Subject: [PATCH] net: stmmac: Do not keep rearming the coalesce timer in stmmac_xmit This is cutting down performance. Once the timer is armed it should run after the time expires for the first packet sent and not the last one. After this change, running iperf, the performance gain is +/- 24%. Signed-off-by: Jose Abreu Cc: David S. Miller Cc: Joao Pinto Cc: Vitor Soares Cc: Giuseppe Cavallaro Cc: Alexandre Torgue Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/stmmac.h | 1 + drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 5 ++++- 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h index 42fc76e76bf9d..4d425b1a0c593 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h @@ -105,6 +105,7 @@ struct stmmac_priv { u32 tx_count_frames; u32 tx_coal_frames; u32 tx_coal_timer; + bool tx_timer_armed; int tx_coalesce; int hwts_tx_en; diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index d9dbe13558961..789bc226ba69c 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -3158,13 +3158,16 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev) * element in case of no SG. */ priv->tx_count_frames += nfrags + 1; - if (likely(priv->tx_coal_frames > priv->tx_count_frames)) { + if (likely(priv->tx_coal_frames > priv->tx_count_frames) && + !priv->tx_timer_armed) { mod_timer(&priv->txtimer, STMMAC_COAL_TIMER(priv->tx_coal_timer)); + priv->tx_timer_armed = true; } else { priv->tx_count_frames = 0; stmmac_set_tx_ic(priv, desc); priv->xstats.tx_set_ic_bit++; + priv->tx_timer_armed = false; } skb_tx_timestamp(skb); -- 2.30.2