From 21b5f672fb2eb1366dedc4ac9d32431146b378d3 Mon Sep 17 00:00:00 2001 From: Heiner Kallweit Date: Wed, 5 Feb 2020 21:22:46 +0100 Subject: 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: 2df49d365498 ("r8169: remove fiddling with the PCIe max read request size") Signed-off-by: Heiner Kallweit Signed-off-by: David S. Miller --- drivers/net/ethernet/realtek/r8169_main.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/net/ethernet') diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c index aaa316be6183..a2168a14794c 100644 --- a/drivers/net/ethernet/realtek/r8169_main.c +++ b/drivers/net/ethernet/realtek/r8169_main.c @@ -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) -- cgit v1.2.3-59-g8ed1b