Re: patch 'net/iavf: add thread for event callbacks' has been queued to stable release 21.11.3

[Kevin Traynor <ktraynor@redhat.com>]

On 11/11/2022 10:33, Kevin Traynor wrote:
> Hi,
> 
> FYI, your patch has been queued to stable release 21.11.3
> 
> Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
> It will be pushed if I get no objections before 11/14/22. So please
> shout if anyone has objections.
> 

This patch is causing a build failure on Windows [1]. I won't push it to 
to the dpdk-stable 21.11 branch. Please send a rebased version, or let 
me know if it should be dropped from 21.11.

> Also note that after the patch there's a diff of the upstream commit vs the
> patch applied to the branch. This will indicate if there was any rebasing
> needed to apply to the stable branch. If there were code changes for rebasing
> (ie: not only metadata diffs), please double check that the rebase was
> correctly done.
> 
> Queued patches are on a temporary branch at:
> https://github.com/kevintraynor/dpdk-stable
> 
> This queued commit can be viewed at:
> https://github.com/kevintraynor/dpdk-stable/commit/c346009ca9686fabd300f8afe688239426b5eebd
> 
> Thanks.
> 
> Kevin
> 
> ---
>  From c346009ca9686fabd300f8afe688239426b5eebd Mon Sep 17 00:00:00 2001
> From: Yiding Zhou <yidingx.zhou@intel.com>
> Date: Thu, 20 Oct 2022 13:00:22 +0800
> Subject: [PATCH] net/iavf: add thread for event callbacks
> 
> [ upstream commit cb5c1b91f76f436724cd09f26c7432b2775b519c ]
> 
> All callbacks registered for ethdev events are called in
> eal-intr-thread, and some of them execute virtchnl commands.
> Because interrupts are disabled in the intr thread, no response
> will be received for these commands. So all callbacks should
> be called in a new context.
> 
> When the device is bonded, the bond pmd registers a callback for
> the LSC event to execute virtchnl commands to reinitialize the
> device, and it would also raise the above issue.
> 
> This commit adds a new thread to call all event callbacks.
> 
> Fixes: 48de41ca11f0 ("net/avf: enable link status update")
> Fixes: 84108425054a ("net/iavf: support asynchronous virtual channel message")
> 
> Signed-off-by: Yiding Zhou <yidingx.zhou@intel.com>
> Acked-by: Qi Zhang <qi.z.zhang@intel.com>
> ---
>   drivers/net/iavf/iavf.h        |   2 +
>   drivers/net/iavf/iavf_ethdev.c |   5 ++
>   drivers/net/iavf/iavf_vchnl.c  | 153 +++++++++++++++++++++++++++++++--
>   3 files changed, 154 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/net/iavf/iavf.h b/drivers/net/iavf/iavf.h
> index 29692e3994..afffc1a13e 100644
> --- a/drivers/net/iavf/iavf.h
> +++ b/drivers/net/iavf/iavf.h
> @@ -401,4 +401,6 @@ _atomic_set_async_response_cmd(struct iavf_info *vf, enum virtchnl_ops ops)
>   int iavf_check_api_version(struct iavf_adapter *adapter);
>   int iavf_get_vf_resource(struct iavf_adapter *adapter);
> +void iavf_dev_event_handler_fini(void);
> +int iavf_dev_event_handler_init(void);
>   void iavf_handle_virtchnl_msg(struct rte_eth_dev *dev);
>   int iavf_enable_vlan_strip(struct iavf_adapter *adapter);
> diff --git a/drivers/net/iavf/iavf_ethdev.c b/drivers/net/iavf/iavf_ethdev.c
> index f835457e4f..11ddd6dc16 100644
> --- a/drivers/net/iavf/iavf_ethdev.c
> +++ b/drivers/net/iavf/iavf_ethdev.c
> @@ -2562,4 +2562,7 @@ iavf_dev_init(struct rte_eth_dev *eth_dev)
>   			&eth_dev->data->mac_addrs[0]);
>   
> +	if (iavf_dev_event_handler_init())
> +		goto init_vf_err;
> +
>   	if (vf->vf_res->vf_cap_flags & VIRTCHNL_VF_OFFLOAD_WB_ON_ITR) {
>   		/* register callback func to eal lib */
> @@ -2716,4 +2719,6 @@ iavf_dev_uninit(struct rte_eth_dev *dev)
>   	iavf_dev_close(dev);
>   
> +	iavf_dev_event_handler_fini();
> +
>   	return 0;
>   }
> diff --git a/drivers/net/iavf/iavf_vchnl.c b/drivers/net/iavf/iavf_vchnl.c
> index 1bd3559ec2..54c6e39e16 100644
> --- a/drivers/net/iavf/iavf_vchnl.c
> +++ b/drivers/net/iavf/iavf_vchnl.c
> @@ -3,4 +3,5 @@
>    */
>   
> +#include <fcntl.h>
>   #include <stdio.h>
>   #include <errno.h>
> @@ -12,4 +13,5 @@
>   #include <rte_byteorder.h>
>   #include <rte_common.h>
> +#include <rte_os_shim.h>
>   
>   #include <rte_debug.h>
> @@ -28,4 +30,144 @@
>   #define ASQ_DELAY_MS  1
>   
> +#define MAX_EVENT_PENDING 16
> +
> +struct iavf_event_element {
> +	TAILQ_ENTRY(iavf_event_element) next;
> +	struct rte_eth_dev *dev;
> +	enum rte_eth_event_type event;
> +	void *param;
> +	size_t param_alloc_size;
> +	uint8_t param_alloc_data[0];
> +};
> +
> +struct iavf_event_handler {
> +	uint32_t ndev;
> +	pthread_t tid;
> +	int fd[2];
> +	pthread_mutex_t lock;
> +	TAILQ_HEAD(event_list, iavf_event_element) pending;
> +};
> +
> +static struct iavf_event_handler event_handler = {
> +	.fd = {-1, -1},
> +};
> +
> +#ifndef TAILQ_FOREACH_SAFE
> +#define TAILQ_FOREACH_SAFE(var, head, field, tvar) \
> +	for ((var) = TAILQ_FIRST((head)); \
> +		(var) && ((tvar) = TAILQ_NEXT((var), field), 1); \
> +	(var) = (tvar))
> +#endif
> +
> +static void *
> +iavf_dev_event_handle(void *param __rte_unused)
> +{
> +	struct iavf_event_handler *handler = &event_handler;
> +	TAILQ_HEAD(event_list, iavf_event_element) pending;
> +
> +	while (true) {
> +		char unused[MAX_EVENT_PENDING];
> +		ssize_t nr = read(handler->fd[0], &unused, sizeof(unused));
> +		if (nr <= 0)
> +			break;
> +
> +		TAILQ_INIT(&pending);
> +		pthread_mutex_lock(&handler->lock);
> +		TAILQ_CONCAT(&pending, &handler->pending, next);
> +		pthread_mutex_unlock(&handler->lock);
> +
> +		struct iavf_event_element *pos, *save_next;
> +		TAILQ_FOREACH_SAFE(pos, &pending, next, save_next) {
> +			TAILQ_REMOVE(&pending, pos, next);
> +			rte_eth_dev_callback_process(pos->dev, pos->event, pos->param);
> +			rte_free(pos);
> +		}
> +	}
> +
> +	return NULL;
> +}
> +
> +static void
> +iavf_dev_event_post(struct rte_eth_dev *dev,
> +		enum rte_eth_event_type event,
> +		void *param, size_t param_alloc_size)
> +{
> +	struct iavf_event_handler *handler = &event_handler;
> +	char notify_byte;
> +	struct iavf_event_element *elem = rte_malloc(NULL, sizeof(*elem) + param_alloc_size, 0);
> +	if (!elem)
> +		return;
> +
> +	elem->dev = dev;
> +	elem->event = event;
> +	elem->param = param;
> +	elem->param_alloc_size = param_alloc_size;
> +	if (param && param_alloc_size) {
> +		rte_memcpy(elem->param_alloc_data, param, param_alloc_size);
> +		elem->param = elem->param_alloc_data;
> +	}
> +
> +	pthread_mutex_lock(&handler->lock);
> +	TAILQ_INSERT_TAIL(&handler->pending, elem, next);
> +	pthread_mutex_unlock(&handler->lock);
> +
> +	ssize_t nw = write(handler->fd[1], &notify_byte, 1);
> +	RTE_SET_USED(nw);
> +}
> +
> +int
> +iavf_dev_event_handler_init(void)
> +{
> +	struct iavf_event_handler *handler = &event_handler;
> +
> +	if (__atomic_add_fetch(&handler->ndev, 1, __ATOMIC_RELAXED) != 1)
> +		return 0;
> +#if defined(RTE_EXEC_ENV_IS_WINDOWS) && RTE_EXEC_ENV_IS_WINDOWS != 0
> +	int err = _pipe(handler->fd, MAX_EVENT_PENDING, O_BINARY);
> +#else
> +	int err = pipe(handler->fd);
> +#endif

../drivers/net/iavf/iavf_vchnl.c:128:12: error: implicit declaration of 
function 'pipe' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
         int err = pipe(handler->fd);
                   ^
../drivers/net/iavf/iavf_vchnl.c:128:12: note: did you mean '_pipe'?
C:\Program Files (x86)\Windows 
Kits\10\Include\10.0.18362.0\ucrt\corecrt_io.h:241:30: note: '_pipe' 
declared here
         _DCRTIMP int __cdecl _pipe(

From: https://dpdkdashboard.iol.unh.edu/results/dashboard/tarballs/22355/

> +	if (err != 0) {
> +		__atomic_sub_fetch(&handler->ndev, 1, __ATOMIC_RELAXED);
> +		return -1;
> +	}
> +
> +	TAILQ_INIT(&handler->pending);
> +	pthread_mutex_init(&handler->lock, NULL);
> +
> +	if (rte_ctrl_thread_create(&handler->tid, "iavf-event-thread",
> +				NULL, iavf_dev_event_handle, NULL)) {
> +		__atomic_sub_fetch(&handler->ndev, 1, __ATOMIC_RELAXED);
> +		return -1;
> +	}
> +
> +	return 0;
> +}
> +
> +void
> +iavf_dev_event_handler_fini(void)
> +{
> +	struct iavf_event_handler *handler = &event_handler;
> +
> +	if (__atomic_sub_fetch(&handler->ndev, 1, __ATOMIC_RELAXED) != 0)
> +		return;
> +
> +	int unused = pthread_cancel(handler->tid);
> +	RTE_SET_USED(unused);
> +	close(handler->fd[0]);
> +	close(handler->fd[1]);
> +	handler->fd[0] = -1;
> +	handler->fd[1] = -1;
> +
> +	pthread_join(handler->tid, NULL);
> +	pthread_mutex_destroy(&handler->lock);
> +
> +	struct iavf_event_element *pos, *save_next;
> +	TAILQ_FOREACH_SAFE(pos, &handler->pending, next, save_next) {
> +		TAILQ_REMOVE(&handler->pending, pos, next);
> +		rte_free(pos);
> +	}
> +}
> +
>   static uint32_t
>   iavf_convert_link_speed(enum virtchnl_link_speed virt_link_speed)
> @@ -279,6 +421,6 @@ iavf_handle_pf_event_msg(struct rte_eth_dev *dev, uint8_t *msg,
>   		PMD_DRV_LOG(DEBUG, "VIRTCHNL_EVENT_RESET_IMPENDING event");
>   		vf->vf_reset = true;
> -		rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_RESET,
> -					      NULL);
> +		iavf_dev_event_post(dev, RTE_ETH_EVENT_INTR_RESET,
> +					      NULL, 0);
>   		break;
>   	case VIRTCHNL_EVENT_LINK_CHANGE:
> @@ -294,5 +436,5 @@ iavf_handle_pf_event_msg(struct rte_eth_dev *dev, uint8_t *msg,
>   		}
>   		iavf_dev_link_update(dev, 0);
> -		rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
> +		iavf_dev_event_post(dev, RTE_ETH_EVENT_INTR_LSC, NULL, 0);
>   		break;
>   	case VIRTCHNL_EVENT_PF_DRIVER_CLOSE:
> @@ -360,7 +502,6 @@ iavf_handle_virtchnl_msg(struct rte_eth_dev *dev)
>   						RTE_ETH_EVENT_IPSEC_UNKNOWN;
>   					desc.metadata = ev->ipsec_event_data;
> -					rte_eth_dev_callback_process(dev,
> -							RTE_ETH_EVENT_IPSEC,
> -							&desc);
> +					iavf_dev_event_post(dev, RTE_ETH_EVENT_IPSEC,
> +							&desc, sizeof(desc));
>   					return;
>   				}