[PATCH AUTOSEL 5.1 030/219] net: stmmac: Prevent missing interrupts when running NAPI

From: Sasha Levin
Date: Mon Jul 15 2019 - 11:05:41 EST


From: Jose Abreu <Jose.Abreu@xxxxxxxxxxxx>

[ Upstream commit a976ca79e23f13bff79c14e7266cea4a0ea51e67 ]

When we trigger NAPI we are disabling interrupts but in case we receive
or send a packet in the meantime, as interrupts are disabled, we will
miss this event.

Trigger both NAPI instances (RX and TX) when at least one event happens
so that we don't miss any interrupts.

Signed-off-by: Jose Abreu <joabreu@xxxxxxxxxxxx>
Cc: Joao Pinto <jpinto@xxxxxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: Giuseppe Cavallaro <peppe.cavallaro@xxxxxx>
Cc: Alexandre Torgue <alexandre.torgue@xxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index a634054dcb11..f3735d0458eb 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -2058,6 +2058,9 @@ static int stmmac_napi_check(struct stmmac_priv *priv, u32 chan)
&priv->xstats, chan);
struct stmmac_channel *ch = &priv->channel[chan];

+ if (status)
+ status |= handle_rx | handle_tx;
+
if ((status & handle_rx) && (chan < priv->plat->rx_queues_to_use)) {
stmmac_disable_dma_irq(priv, priv->ioaddr, chan);
napi_schedule_irqoff(&ch->rx_napi);
--
2.20.1