2021-12-06 09:06:06

by Joakim Zhang

[permalink] [raw]
Subject: [PATCH] net: fec: only clear interrupt of handling queue in fec_enet_rx_queue()

Only clear interrupt of handling queue in fec_enet_rx_queue(), to avoid
missing packets caused by clear interrupt of other queues.

Signed-off-by: Joakim Zhang <[email protected]>
---
drivers/net/ethernet/freescale/fec_main.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 09df434b2f87..eeefed3043ad 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -1506,7 +1506,12 @@ fec_enet_rx_queue(struct net_device *ndev, int budget, u16 queue_id)
break;
pkt_received++;

- writel(FEC_ENET_RXF, fep->hwp + FEC_IEVENT);
+ if (queue_id == 0)
+ writel(FEC_ENET_RXF_0, fep->hwp + FEC_IEVENT);
+ else if (queue_id == 1)
+ writel(FEC_ENET_RXF_1, fep->hwp + FEC_IEVENT);
+ else
+ writel(FEC_ENET_RXF_2, fep->hwp + FEC_IEVENT);

/* Check for errors. */
status ^= BD_ENET_RX_LAST;
--
2.17.1



2021-12-06 13:04:58

by Andrew Lunn

[permalink] [raw]
Subject: Re: [PATCH] net: fec: only clear interrupt of handling queue in fec_enet_rx_queue()

On Mon, Dec 06, 2021 at 05:05:53PM +0800, Joakim Zhang wrote:
> Only clear interrupt of handling queue in fec_enet_rx_queue(), to avoid
> missing packets caused by clear interrupt of other queues.
>
> Signed-off-by: Joakim Zhang <[email protected]>
> ---
> drivers/net/ethernet/freescale/fec_main.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
> index 09df434b2f87..eeefed3043ad 100644
> --- a/drivers/net/ethernet/freescale/fec_main.c
> +++ b/drivers/net/ethernet/freescale/fec_main.c
> @@ -1506,7 +1506,12 @@ fec_enet_rx_queue(struct net_device *ndev, int budget, u16 queue_id)
> break;
> pkt_received++;
>
> - writel(FEC_ENET_RXF, fep->hwp + FEC_IEVENT);
> + if (queue_id == 0)
> + writel(FEC_ENET_RXF_0, fep->hwp + FEC_IEVENT);
> + else if (queue_id == 1)
> + writel(FEC_ENET_RXF_1, fep->hwp + FEC_IEVENT);
> + else
> + writel(FEC_ENET_RXF_2, fep->hwp + FEC_IEVENT);

The change itself seems find.

Reviewed-by: Andrew Lunn <[email protected]>

But could it be moved out of the loop? If you have a budget of 64,
don't you clear this bit 64 times? Can you just clearing it once on
exit?

Andrew

2021-12-06 13:15:17

by Joakim Zhang

[permalink] [raw]
Subject: RE: [PATCH] net: fec: only clear interrupt of handling queue in fec_enet_rx_queue()


Hi Andrew,

> -----Original Message-----
> From: Andrew Lunn <[email protected]>
> Sent: 2021??12??6?? 21:05
> To: Joakim Zhang <[email protected]>
> Cc: [email protected]; [email protected]; Nicolas Diaz
> <[email protected]>; [email protected];
> [email protected]; [email protected]; dl-linux-imx
> <[email protected]>
> Subject: Re: [PATCH] net: fec: only clear interrupt of handling queue in
> fec_enet_rx_queue()
>
> On Mon, Dec 06, 2021 at 05:05:53PM +0800, Joakim Zhang wrote:
> > Only clear interrupt of handling queue in fec_enet_rx_queue(), to
> > avoid missing packets caused by clear interrupt of other queues.
> >
> > Signed-off-by: Joakim Zhang <[email protected]>
> > ---
> > drivers/net/ethernet/freescale/fec_main.c | 7 ++++++-
> > 1 file changed, 6 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/ethernet/freescale/fec_main.c
> > b/drivers/net/ethernet/freescale/fec_main.c
> > index 09df434b2f87..eeefed3043ad 100644
> > --- a/drivers/net/ethernet/freescale/fec_main.c
> > +++ b/drivers/net/ethernet/freescale/fec_main.c
> > @@ -1506,7 +1506,12 @@ fec_enet_rx_queue(struct net_device *ndev,
> int budget, u16 queue_id)
> > break;
> > pkt_received++;
> >
> > - writel(FEC_ENET_RXF, fep->hwp + FEC_IEVENT);
> > + if (queue_id == 0)
> > + writel(FEC_ENET_RXF_0, fep->hwp + FEC_IEVENT);
> > + else if (queue_id == 1)
> > + writel(FEC_ENET_RXF_1, fep->hwp + FEC_IEVENT);
> > + else
> > + writel(FEC_ENET_RXF_2, fep->hwp + FEC_IEVENT);
>
> The change itself seems find.
>
> Reviewed-by: Andrew Lunn <[email protected]>
>
> But could it be moved out of the loop? If you have a budget of 64, don't you
> clear this bit 64 times? Can you just clearing it once on exit?

Apologize first, I have a formal patch but send out the informal one, I will re-send later, sorry for inconvenience.

About you question, yes, we need to clear this bit each time, the blamed patch introduced to avoiding interrupt flooding.

> Andrew