| Message ID | 20210608212107.222690-1-olek2@wp.pl |
|---|---|
| State | New |
| Headers | show |
| Series | [net] net: lantiq: disable interrupt before sheduling NAPI | expand |
On 6/8/21 11:21 PM, Aleksander Jan Bajkowski wrote: > This patch fixes TX hangs with threaded NAPI enabled. The scheduled > NAPI seems to be executed in parallel with the interrupt on second > thread. Sometimes it happens that ltq_dma_disable_irq() is executed > after xrx200_tx_housekeeping(). The symptom is that TX interrupts > are disabled in the DMA controller. As a result, the TX hangs after > a few seconds of the iperf test. Scheduling NAPI after disabling > interrupts fixes this issue. > > Tested on Lantiq xRX200 (BT Home Hub 5A). > > Fixes: 9423361da523 ("net: lantiq: Disable IRQs only if NAPI gets scheduled ") > Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl> Acked-by: Hauke Mehrtens <hauke@hauke-m.de> > --- > drivers/net/ethernet/lantiq_xrx200.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c > index 36dc3e5f6218..0e10d8aeffe1 100644 > --- a/drivers/net/ethernet/lantiq_xrx200.c > +++ b/drivers/net/ethernet/lantiq_xrx200.c > @@ -352,8 +352,8 @@ static irqreturn_t xrx200_dma_irq(int irq, void *ptr) > struct xrx200_chan *ch = ptr; > > if (napi_schedule_prep(&ch->napi)) { > - __napi_schedule(&ch->napi); > ltq_dma_disable_irq(&ch->dma); > + __napi_schedule(&ch->napi); > } > > ltq_dma_ack_irq(&ch->dma); >
Hello: This patch was applied to netdev/net.git (refs/heads/master): On Tue, 8 Jun 2021 23:21:07 +0200 you wrote: > This patch fixes TX hangs with threaded NAPI enabled. The scheduled > NAPI seems to be executed in parallel with the interrupt on second > thread. Sometimes it happens that ltq_dma_disable_irq() is executed > after xrx200_tx_housekeeping(). The symptom is that TX interrupts > are disabled in the DMA controller. As a result, the TX hangs after > a few seconds of the iperf test. Scheduling NAPI after disabling > interrupts fixes this issue. > > [...] Here is the summary with links: - [net] net: lantiq: disable interrupt before sheduling NAPI https://git.kernel.org/netdev/net/c/f2386cf7c5f4 You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c index 36dc3e5f6218..0e10d8aeffe1 100644 --- a/drivers/net/ethernet/lantiq_xrx200.c +++ b/drivers/net/ethernet/lantiq_xrx200.c @@ -352,8 +352,8 @@ static irqreturn_t xrx200_dma_irq(int irq, void *ptr) struct xrx200_chan *ch = ptr; if (napi_schedule_prep(&ch->napi)) { - __napi_schedule(&ch->napi); ltq_dma_disable_irq(&ch->dma); + __napi_schedule(&ch->napi); } ltq_dma_ack_irq(&ch->dma);
This patch fixes TX hangs with threaded NAPI enabled. The scheduled NAPI seems to be executed in parallel with the interrupt on second thread. Sometimes it happens that ltq_dma_disable_irq() is executed after xrx200_tx_housekeeping(). The symptom is that TX interrupts are disabled in the DMA controller. As a result, the TX hangs after a few seconds of the iperf test. Scheduling NAPI after disabling interrupts fixes this issue. Tested on Lantiq xRX200 (BT Home Hub 5A). Fixes: 9423361da523 ("net: lantiq: Disable IRQs only if NAPI gets scheduled ") Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl> --- drivers/net/ethernet/lantiq_xrx200.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)