Commit 21b5f672 authored by Heiner Kallweit's avatar Heiner Kallweit Committed by David S. Miller
Browse files

r8169: fix performance regression related to PCIe max read request size 



It turned out that on low performance systems the original change can
cause lower tx performance. On a N3450-based mini-PC tx performance
in iperf3 was reduced from 950Mbps to ~900Mbps. Therefore effectively
revert the original change, just use pcie_set_readrq() now instead of
changing the PCIe capability register directly.

Fixes: 2df49d36 ("r8169: remove fiddling with the PCIe max read request size")
Signed-off-by: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 7a02ea65

drivers/net/ethernet/realtek/r8169_main.c

+6 −0
Original line number Diff line number Diff line
@@ -2477,15 +2477,18 @@ static void rtl_hw_jumbo_enable(struct rtl8169_private *tp) 
	switch (tp->mac_version) {

	case RTL_GIGA_MAC_VER_12:

	case RTL_GIGA_MAC_VER_17:

		pcie_set_readrq(tp->pci_dev, 512);

		r8168b_1_hw_jumbo_enable(tp);

		break;

	case RTL_GIGA_MAC_VER_18 ... RTL_GIGA_MAC_VER_26:

		pcie_set_readrq(tp->pci_dev, 512);

		r8168c_hw_jumbo_enable(tp);

		break;

	case RTL_GIGA_MAC_VER_27 ... RTL_GIGA_MAC_VER_28:

		r8168dp_hw_jumbo_enable(tp);

		break;

	case RTL_GIGA_MAC_VER_31 ... RTL_GIGA_MAC_VER_33:

		pcie_set_readrq(tp->pci_dev, 512);

		r8168e_hw_jumbo_enable(tp);

		break;

	default:
@@ -2515,6 +2518,9 @@ static void rtl_hw_jumbo_disable(struct rtl8169_private *tp) 
		break;

	}

	rtl_lock_config_regs(tp);



	if (pci_is_pcie(tp->pci_dev) && tp->supports_gmii)

		pcie_set_readrq(tp->pci_dev, 4096);

}



static void rtl_jumbo_config(struct rtl8169_private *tp, int mtu)

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