On Fri, Oct 11, 2019 at 05:15:03PM +0300, Ilias Apalodimas wrote:
> Hi Lorenzo,
>
> On Fri, Oct 11, 2019 at 03:45:38PM +0200, Lorenzo Bianconi wrote:
> > Increment netdev rx counters even for XDP_DROP verdict. Moreover report
> > even tx bytes for xdp buffers (TYPE_NETSEC_XDP_TX or
> > TYPE_NETSEC_XDP_NDO)
>
> The RX counters work fine. The TX change is causing a panic though and i am
> looking into it since your patch seems harmless. In any case please don't
> merge
> this yet
>
Ok i think i know what's going on.
Our clean TX routine has a netdev_completed_queue(). This is properly accounted
for on netsec_netdev_start_xmit() which calls netdev_sent_queue().
Since the XDP never had support for that you need to account for the extra bytes
in netsec_xdp_queue_one(). That's what triggering the BUG_ON
(lib/dynamic_queue_limits.c line 27)
Since netdev_completed_queue() enforces barrier() and in some cases smp_mb() i
think i'd prefer it per function, although it looks uglier.
Can you send a patch with this call in netsec_xdp_queue_one()? If we cant
measure any performance difference i am fine with adding it in that only.
Thanks
/Ilias
> Thanks
> /Ilias
>
> > Fixes: ba2b232108d3 ("net: netsec: add XDP support")
> > Signed-off-by: Lorenzo Bianconi <lore...@kernel.org>
> > ---
> > just compiled not tested on a real device
> > ---
> > drivers/net/ethernet/socionext/netsec.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/socionext/netsec.c
> > b/drivers/net/ethernet/socionext/netsec.c
> > index f9e6744d8fd6..b1c2a79899b3 100644
> > --- a/drivers/net/ethernet/socionext/netsec.c
> > +++ b/drivers/net/ethernet/socionext/netsec.c
> > @@ -252,7 +252,6 @@
> > #define NETSEC_XDP_CONSUMED BIT(0)
> > #define NETSEC_XDP_TX BIT(1)
> > #define NETSEC_XDP_REDIR BIT(2)
> > -#define NETSEC_XDP_RX_OK (NETSEC_XDP_PASS | NETSEC_XDP_TX |
> > NETSEC_XDP_REDIR)
> >
> > enum ring_id {
> > NETSEC_RING_TX = 0,
> > @@ -661,6 +660,7 @@ static bool netsec_clean_tx_dring(struct netsec_priv
> > *priv)
> > bytes += desc->skb->len;
> > dev_kfree_skb(desc->skb);
> > } else {
> > + bytes += desc->xdpf->len;
> > xdp_return_frame(desc->xdpf);
> > }
> > next:
> > @@ -1030,7 +1030,7 @@ static int netsec_process_rx(struct netsec_priv
> > *priv, int budget)
> >
> > next:
> > if ((skb && napi_gro_receive(&priv->napi, skb) != GRO_DROP) ||
> > - xdp_result & NETSEC_XDP_RX_OK) {
> > + xdp_result) {
> > ndev->stats.rx_packets++;
> > ndev->stats.rx_bytes += xdp.data_end - xdp.data;
> > }
> > --
> > 2.21.0
> >
