On Fri, Jun 28, 2019 at 3:30 AM Jose Abreu <jose.ab...@synopsys.com> wrote:
>
> This is a performance killer and anyways the interrupts are being
> disabled by RX NAPI so no need to disable them again.
By the
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);
}
branch directly above? If so, is it possible to have fewer rx than tx
queues and miss this?
this logic seems more complex than needed?
if (status)
status |= handle_rx | handle_tx;
if ((status & handle_rx) && (chan < priv->plat->rx_queues_to_use)) {
}
if ((status & handle_tx) && (chan < priv->plat->tx_queues_to_use)) {
}
status & handle_rx implies status & handle_tx and vice versa.
>
> Signed-off-by: Jose Abreu <joab...@synopsys.com>
> Cc: Joao Pinto <jpi...@synopsys.com>
> Cc: David S. Miller <da...@davemloft.net>
> Cc: Giuseppe Cavallaro <peppe.cavall...@st.com>
> Cc: Alexandre Torgue <alexandre.tor...@st.com>
> ---
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 8 +++-----
> 1 file changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> index 4a5941caaadc..e8f3e76889c8 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> @@ -2061,10 +2061,8 @@ static int stmmac_napi_check(struct stmmac_priv *priv,
> u32 chan)
> napi_schedule_irqoff(&ch->rx_napi);
> }
>
> - if ((status & handle_tx) && (chan < priv->plat->tx_queues_to_use)) {
> - stmmac_disable_dma_irq(priv, priv->ioaddr, chan);
> + if ((status & handle_tx) && (chan < priv->plat->tx_queues_to_use))
> napi_schedule_irqoff(&ch->tx_napi);
> - }
>
> return status;
> }
> @@ -3570,8 +3568,8 @@ static int stmmac_napi_poll_tx(struct napi_struct
> *napi, int budget)
> work_done = stmmac_tx_clean(priv, DMA_TX_SIZE, chan);
> work_done = min(work_done, budget);
>
> - if (work_done < budget && napi_complete_done(napi, work_done))
> - stmmac_enable_dma_irq(priv, priv->ioaddr, chan);
> + if (work_done < budget)
> + napi_complete_done(napi, work_done);
It does seem odd that stmmac_napi_poll_rx and stmmac_napi_poll_tx both
call stmmac_enable_dma_irq(..) independent of the other. Shouldn't the
IRQ remain masked while either is active or scheduled? That is almost
what this patch does, though not exactly.
