NAPI poll of Realtek NICs don't seem to perform well ASPM is enabled.
The vendor driver uses a mechanism called "dynamic ASPM" to toggle ASPM
based on the packet number in given time period.
Instead of implementing "dynamic ASPM", use a more straightforward way
by disabling ASPM during NAPI poll, as a similar approach was
implemented to solve slow performance on Realtek wireless NIC, see
commit 24f5e38a13b5 ("rtw88: Disable PCIe ASPM while doing NAPI poll on
8821CE").
Since NAPI poll should be handled as fast as possible, also remove the
delay in rtl_hw_aspm_clkreq_enable() which was added by commit
94235460f9eaef ("r8169: Align ASPM/CLKREQ setting function with vendor
driver").
Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
---
v9:
- No change.
v8:
- New patch.
drivers/net/ethernet/realtek/r8169_main.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index fb73b5386701f..4e874fa661852 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -2711,8 +2711,6 @@ static void rtl_hw_aspm_clkreq_enable(struct rtl8169_private *tp, bool enable)
RTL_W8(tp, Config2, RTL_R8(tp, Config2) & ~ClkReqEn);
RTL_W8(tp, Config5, RTL_R8(tp, Config5) & ~ASPM_en);
}
-
- udelay(10);
}
static void rtl_set_fifo_size(struct rtl8169_private *tp, u16 rx_stat,
@@ -4577,6 +4575,12 @@ static int rtl8169_poll(struct napi_struct *napi, int budget)
struct net_device *dev = tp->dev;
int work_done;
+ if (tp->aspm_manageable) {
+ rtl_unlock_config_regs(tp);
+ rtl_hw_aspm_clkreq_enable(tp, false);
+ rtl_lock_config_regs(tp);
+ }
+
rtl_tx(dev, tp, budget);
work_done = rtl_rx(dev, tp, budget);
@@ -4584,6 +4588,12 @@ static int rtl8169_poll(struct napi_struct *napi, int budget)
if (work_done < budget && napi_complete_done(napi, work_done))
rtl_irq_enable(tp);
+ if (tp->aspm_manageable) {
+ rtl_unlock_config_regs(tp);
+ rtl_hw_aspm_clkreq_enable(tp, true);
+ rtl_lock_config_regs(tp);
+ }
+
return work_done;
}
--
2.34.1
