| Message ID | 20220228111558.3825974-1-vee.khee.wong@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [net,1/1] net: stmmac: Resolve poor line rate after switching from TSO off to TSO on | expand |
On Mon, 28 Feb 2022 19:15:58 +0800 Wong Vee Khee wrote: > From: Ling Pei Lee <pei.lee.ling@intel.com> > > Sequential execution of these steps: > i) TSO ON – iperf3 execution, > ii) TSO OFF – iperf3 execution, > iii) TSO ON – iperf3 execution, it leads to iperf3 0 bytes transfer. IMHO the iperf output can be dropped from the commit message, it doesn't add much beyond this description. > Clear mss in TDES and call stmmac_enable_tso() to indicate > a new TSO transmission when it is enabled from TSO off using > ethtool command How does the TSO get disabled I don't see any ...enable_tso(, 0, ) calls in the driver? And why call enable in fix_features rather than set_features?
On Wed, Mar 02, 2022 at 10:32:48PM -0800, Jakub Kicinski wrote: > On Mon, 28 Feb 2022 19:15:58 +0800 Wong Vee Khee wrote: > > From: Ling Pei Lee <pei.lee.ling@intel.com> > > > > Sequential execution of these steps: > > i) TSO ON – iperf3 execution, > > ii) TSO OFF – iperf3 execution, > > iii) TSO ON – iperf3 execution, it leads to iperf3 0 bytes transfer. > > IMHO the iperf output can be dropped from the commit message, > it doesn't add much beyond this description. > Noted. Will drop those on next revision of pull request. > > Clear mss in TDES and call stmmac_enable_tso() to indicate > > a new TSO transmission when it is enabled from TSO off using > > ethtool command > > How does the TSO get disabled I don't see any ...enable_tso(, 0, ) > calls in the driver? And why call enable in fix_features rather > than set_features? It is disable when 'priv->tso = 0' in this same function. The reason I put this in fix_features rather than set_features is because the commit f748be531d70("stmmac: support new GMAC4") has already introduced the following codes in fix_features:- + /* Disable tso if asked by ethtool */ + if ((priv->plat->tso_en) && (priv->dma_cap.tsoen)) { + if (features & NETIF_F_TSO) + priv->tso = true; + else + priv->tso = false; + } BR, Vee Khee
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index b745d624b2cb..9e2ea0e0bd68 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -5460,6 +5460,8 @@ static netdev_features_t stmmac_fix_features(struct net_device *dev, netdev_features_t features) { struct stmmac_priv *priv = netdev_priv(dev); + u32 tx_cnt = priv->plat->tx_queues_to_use; + u32 chan; if (priv->plat->rx_coe == STMMAC_RX_COE_NONE) features &= ~NETIF_F_RXCSUM; @@ -5483,6 +5485,16 @@ static netdev_features_t stmmac_fix_features(struct net_device *dev, priv->tso = false; } + for (chan = 0; chan < tx_cnt; chan++) { + struct stmmac_tx_queue *tx_q = &priv->tx_queue[chan]; + + /* TSO and TBS cannot co-exist */ + if (tx_q->tbs & STMMAC_TBS_AVAIL) + continue; + + tx_q->mss = 0; + stmmac_enable_tso(priv, priv->ioaddr, priv->tso, chan); + } return features; }