[PATCH v6 8/9] vhost: annotate vDPA device list accesses

[Xia, Chenbo]

> -----Original Message-----
> From: David Marchand <david.marchand at redhat.com>
> Sent: Tuesday, February 7, 2023 6:46 PM
> To: dev at dpdk.org
> Cc: maxime.coquelin at redhat.com; stephen at networkplumber.org; Xia, Chenbo
> <chenbo.xia at intel.com>; Hu, Jiayu <jiayu.hu at intel.com>; Wang, YuanX
> <yuanx.wang at intel.com>; Ding, Xuan <xuan.ding at intel.com>;
> mb at smartsharesystems.com
> Subject: [PATCH v6 8/9] vhost: annotate vDPA device list accesses
> 
> Access to vdpa_device_list must be protected with vdpa_device_list_lock
> spinlock.
> 
> Signed-off-by: David Marchand <david.marchand at redhat.com>
> Acked-by: Morten Brørup <mb at smartsharesystems.com>
> Reviewed-by: Maxime Coquelin <maxime.coquelin at redhat.com>
> ---
> Changes since RFC v3:
> - rebased,
> 
> ---
>  lib/vhost/vdpa.c | 19 ++++++++++---------
>  1 file changed, 10 insertions(+), 9 deletions(-)
> 
> diff --git a/lib/vhost/vdpa.c b/lib/vhost/vdpa.c
> index a430a66970..6284ea2ed1 100644
> --- a/lib/vhost/vdpa.c
> +++ b/lib/vhost/vdpa.c
> @@ -23,21 +23,22 @@
>  /** Double linked list of vDPA devices. */
>  TAILQ_HEAD(vdpa_device_list, rte_vdpa_device);
> 
> -static struct vdpa_device_list vdpa_device_list =
> -		TAILQ_HEAD_INITIALIZER(vdpa_device_list);
> +static struct vdpa_device_list vdpa_device_list__ =
> +	TAILQ_HEAD_INITIALIZER(vdpa_device_list__);
>  static rte_spinlock_t vdpa_device_list_lock = RTE_SPINLOCK_INITIALIZER;
> +static struct vdpa_device_list * const vdpa_device_list
> +	__rte_guarded_by(&vdpa_device_list_lock) = &vdpa_device_list__;
> 
> -
> -/* Unsafe, needs to be called with vdpa_device_list_lock held */
>  static struct rte_vdpa_device *
>  __vdpa_find_device_by_name(const char *name)
> +	__rte_exclusive_locks_required(&vdpa_device_list_lock)
>  {
>  	struct rte_vdpa_device *dev, *ret = NULL;
> 
>  	if (name == NULL)
>  		return NULL;
> 
> -	TAILQ_FOREACH(dev, &vdpa_device_list, next) {
> +	TAILQ_FOREACH(dev, vdpa_device_list, next) {
>  		if (!strncmp(dev->device->name, name, RTE_DEV_NAME_MAX_LEN)) {
>  			ret = dev;
>  			break;
> @@ -116,7 +117,7 @@ rte_vdpa_register_device(struct rte_device *rte_dev,
>  		dev->type = RTE_VHOST_VDPA_DEVICE_TYPE_NET;
>  	}
> 
> -	TAILQ_INSERT_TAIL(&vdpa_device_list, dev, next);
> +	TAILQ_INSERT_TAIL(vdpa_device_list, dev, next);
>  out_unlock:
>  	rte_spinlock_unlock(&vdpa_device_list_lock);
> 
> @@ -130,11 +131,11 @@ rte_vdpa_unregister_device(struct rte_vdpa_device
> *dev)
>  	int ret = -1;
> 
>  	rte_spinlock_lock(&vdpa_device_list_lock);
> -	RTE_TAILQ_FOREACH_SAFE(cur_dev, &vdpa_device_list, next, tmp_dev) {
> +	RTE_TAILQ_FOREACH_SAFE(cur_dev, vdpa_device_list, next, tmp_dev) {
>  		if (dev != cur_dev)
>  			continue;
> 
> -		TAILQ_REMOVE(&vdpa_device_list, dev, next);
> +		TAILQ_REMOVE(vdpa_device_list, dev, next);
>  		rte_free(dev);
>  		ret = 0;
>  		break;
> @@ -336,7 +337,7 @@ vdpa_find_device(const struct rte_vdpa_device *start,
> rte_vdpa_cmp_t cmp,
> 
>  	rte_spinlock_lock(&vdpa_device_list_lock);
>  	if (start == NULL)
> -		dev = TAILQ_FIRST(&vdpa_device_list);
> +		dev = TAILQ_FIRST(vdpa_device_list);
>  	else
>  		dev = TAILQ_NEXT(start, next);
> 
> --
> 2.39.1

Reviewed-by: Chenbo Xia <chenbo.xia at intel.com>