[dpdk-dev] [PATCH v3 1/6] net/ixgbevf: unregister irq handler when other interrupts not allowed.

[Dai, Wei]

> -----Original Message-----
> From: xiangxia.m.yue at gmail.com [mailto:xiangxia.m.yue at gmail.com]
> Sent: Sunday, January 14, 2018 6:04 PM
> To: Dai, Wei <wei.dai at intel.com>; Xing, Beilei <beilei.xing at intel.com>
> Cc: dev at dpdk.org; Tonghao Zhang <xiangxia.m.yue at gmail.com>
> Subject: [PATCH v3 1/6] net/ixgbevf: unregister irq handler when other
> interrupts not allowed.
> 
> From: Tonghao Zhang <xiangxia.m.yue at gmail.com>
> 
> When bind the ixgbe VF (e.g 82599 card) to igb_uio and enable the
> rx-interrupt, there will be more than one epoll_wait on intr_handle.fd.
> One is in "eal-intr-thread" thread, and the others are in the thread which call
> the "rte_epoll_wait". The problem is that sometimes "eal-intr-thread" thread
> will process the rx interrupt, and then rte_epoll_wait can't get the event
> anymore, and the packets may be lost.
> 
> The patch unregister the status interrupt handler in "eal-intr-thread"
> thread and the ixgbe pf is in the same case.
> 
> Signed-off-by: Tonghao Zhang <xiangxia.m.yue at gmail.com>
> Acked-by: Beilei Xing <beilei.xing at intel.com>
In my feedback to your v2 version of this patch, I mentioned miscellaneous interrupt
need to be handled in eal-intr-thread. 
Your patch removes the handler of PF->VF reset event and leads to missing of 
this event.
My suggestion is still using VFIO-PCI instead of igb_uio for rx-queue interrupt.


> ---
>  drivers/net/ixgbe/ixgbe_ethdev.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c
> b/drivers/net/ixgbe/ixgbe_ethdev.c
> index ff19a56..0e056a2 100644
> --- a/drivers/net/ixgbe/ixgbe_ethdev.c
> +++ b/drivers/net/ixgbe/ixgbe_ethdev.c
> @@ -5078,6 +5078,15 @@ static int
> ixgbevf_dev_xstats_get_names(__rte_unused struct rte_eth_dev *dev,
>  	}
>  	ixgbevf_configure_msix(dev);
> 
> +	if (!rte_intr_allow_others(intr_handle)) {
> +		rte_intr_callback_unregister(intr_handle,
> +					     ixgbevf_dev_interrupt_handler,
> +					     dev);
> +		if (dev->data->dev_conf.intr_conf.lsc != 0)
> +			PMD_INIT_LOG(INFO, "lsc won't enable because of"
> +				     " no intr multiplex");
> +	}
> +
>  	/* When a VF port is bound to VFIO-PCI, only miscellaneous interrupt
>  	 * is mapped to VFIO vector 0 in eth_ixgbevf_dev_init( ).
>  	 * If previous VFIO interrupt mapping setting in eth_ixgbevf_dev_init( )
> @@ -5120,6 +5129,12 @@ static int
> ixgbevf_dev_xstats_get_names(__rte_unused struct rte_eth_dev *dev,
> 
>  	ixgbe_dev_clear_queues(dev);
> 
> +	if (!rte_intr_allow_others(intr_handle))
> +		/* resume to the default handler */
> +		rte_intr_callback_register(intr_handle,
> +					   ixgbevf_dev_interrupt_handler,
> +					   (void *)dev);
> +
>  	/* Clean datapath event and queue/vec mapping */
>  	rte_intr_efd_disable(intr_handle);
>  	if (intr_handle->intr_vec != NULL) {
> --
> 1.8.3.1