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From: "Xia, Chenbo" <chenbo.xia@intel.com>
To: "Liu, Changpeng" <changpeng.liu@intel.com>,
	"dev@dpdk.org" <dev@dpdk.org>
Cc: Maxime Coquelin <maxime.coquelin@redhat.com>,
	David Marchand <david.marchand@redhat.com>
Subject: RE: [PATCH v2] vhost: add new `rte_vhost_vring_call_nonblock` API
Date: Mon, 17 Oct 2022 06:46:41 +0000	[thread overview]
Message-ID: <SN6PR11MB35042F8AD1B6799276EF407E9C299@SN6PR11MB3504.namprd11.prod.outlook.com> (raw)
In-Reply-To: <20221012064007.56040-1-changpeng.liu@intel.com>

Hi Changpeng,

> -----Original Message-----
> From: Liu, Changpeng <changpeng.liu@intel.com>
> Sent: Wednesday, October 12, 2022 2:40 PM
> To: dev@dpdk.org
> Cc: Liu, Changpeng <changpeng.liu@intel.com>; Maxime Coquelin
> <maxime.coquelin@redhat.com>; Xia, Chenbo <chenbo.xia@intel.com>; David
> Marchand <david.marchand@redhat.com>
> Subject: [PATCH v2] vhost: add new `rte_vhost_vring_call_nonblock` API
> 
> Vhost-user library locks all VQ's access lock when processing
> vring based messages, such as SET_VRING_KICK and SET_VRING_CALL,
> and the data processing thread may already be started, e.g: SPDK
> vhost-blk and vhost-scsi will start the data processing thread
> when one vring is ready, then deadlock may happen when SPDK is
> posting interrupts to VM.  Here, we add a new API which allows
> caller to try again later for this case.
> 
> Bugzilla ID: 1015
> Fixes: c5736998305d ("vhost: fix missing virtqueue lock protection")
> 
> Signed-off-by: Changpeng Liu <changpeng.liu@intel.com>
> ---
>  lib/vhost/rte_vhost.h | 15 +++++++++++++++
>  lib/vhost/version.map |  3 +++
>  lib/vhost/vhost.c     | 30 ++++++++++++++++++++++++++++++
>  3 files changed, 48 insertions(+)

For new API, we need to update release_22_11.rst and vhost_lib.rst.

You can refer to http://patchwork.dpdk.org/project/dpdk/patch/20221013092708.4922-2-xuan.ding@intel.com/

Thanks,
Chenbo

> 
> diff --git a/lib/vhost/rte_vhost.h b/lib/vhost/rte_vhost.h
> index bb7d86a432..d22b25cd4e 100644
> --- a/lib/vhost/rte_vhost.h
> +++ b/lib/vhost/rte_vhost.h
> @@ -909,6 +909,21 @@ rte_vhost_clr_inflight_desc_packed(int vid, uint16_t
> vring_idx,
>   */
>  int rte_vhost_vring_call(int vid, uint16_t vring_idx);
> 
> +/**
> + * Notify the guest that used descriptors have been added to the vring.
> This
> + * function acts as a memory barrier.  This function will return -EAGAIN
> when
> + * vq's access lock is held by other thread, user should try again later.
> + *
> + * @param vid
> + *  vhost device ID
> + * @param vring_idx
> + *  vring index
> + * @return
> + *  0 on success, -1 on failure, -EAGAIN for another retry
> + */
> +__rte_experimental
> +int rte_vhost_vring_call_nonblock(int vid, uint16_t vring_idx);
> +
>  /**
>   * Get vhost RX queue avail count.
>   *
> diff --git a/lib/vhost/version.map b/lib/vhost/version.map
> index 7a00b65740..c8c44b8326 100644
> --- a/lib/vhost/version.map
> +++ b/lib/vhost/version.map
> @@ -94,6 +94,9 @@ EXPERIMENTAL {
>  	rte_vhost_async_try_dequeue_burst;
>  	rte_vhost_driver_get_vdpa_dev_type;
>  	rte_vhost_clear_queue;
> +
> +	# added in 22.11
> +	rte_vhost_vring_call_nonblock;
>  };
> 
>  INTERNAL {
> diff --git a/lib/vhost/vhost.c b/lib/vhost/vhost.c
> index 8740aa2788..ed6efb003f 100644
> --- a/lib/vhost/vhost.c
> +++ b/lib/vhost/vhost.c
> @@ -1317,6 +1317,36 @@ rte_vhost_vring_call(int vid, uint16_t vring_idx)
>  	return 0;
>  }
> 
> +int
> +rte_vhost_vring_call_nonblock(int vid, uint16_t vring_idx)
> +{
> +	struct virtio_net *dev;
> +	struct vhost_virtqueue *vq;
> +
> +	dev = get_device(vid);
> +	if (!dev)
> +		return -1;
> +
> +	if (vring_idx >= VHOST_MAX_VRING)
> +		return -1;
> +
> +	vq = dev->virtqueue[vring_idx];
> +	if (!vq)
> +		return -1;
> +
> +	if (!rte_spinlock_trylock(&vq->access_lock))
> +		return -EAGAIN;
> +
> +	if (vq_is_packed(dev))
> +		vhost_vring_call_packed(dev, vq);
> +	else
> +		vhost_vring_call_split(dev, vq);
> +
> +	rte_spinlock_unlock(&vq->access_lock);
> +
> +	return 0;
> +}
> +
>  uint16_t
>  rte_vhost_avail_entries(int vid, uint16_t queue_id)
>  {
> --
> 2.21.3


  parent reply	other threads:[~2022-10-17  6:46 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-09-06  2:22 [PATCH] vhost: use try_lock in rte_vhost_vring_call Changpeng Liu
2022-09-06 21:15 ` Stephen Hemminger
2022-09-07  0:40   ` Liu, Changpeng
2022-09-20  7:12     ` Maxime Coquelin
2022-09-20  2:24 ` Xia, Chenbo
2022-09-20  2:34   ` Liu, Changpeng
2022-09-20  2:53     ` Xia, Chenbo
2022-09-20  3:00       ` Liu, Changpeng
2022-09-20  7:23       ` Maxime Coquelin
2022-09-20  7:30         ` Maxime Coquelin
2022-09-20  7:19 ` Maxime Coquelin
2022-09-20  7:29   ` Liu, Changpeng
2022-09-20  7:34     ` Maxime Coquelin
2022-09-20  7:45       ` Liu, Changpeng
2022-09-20  8:12         ` Maxime Coquelin
2022-09-20  8:43           ` Liu, Changpeng
2022-09-21  9:41             ` Maxime Coquelin
2022-09-21  9:52               ` Liu, Changpeng
2022-10-11 11:56                 ` Maxime Coquelin
2022-10-12  6:40 ` [PATCH v2] vhost: add new `rte_vhost_vring_call_nonblock` API Changpeng Liu
2022-10-13  7:56   ` Maxime Coquelin
2022-10-17  6:46   ` Xia, Chenbo [this message]
2022-10-17  7:17     ` Liu, Changpeng
2022-10-17  7:14   ` [PATCH v3] " Changpeng Liu
2022-10-17  7:39     ` Xia, Chenbo
2022-10-17  7:50       ` Liu, Changpeng
2022-10-17  7:48     ` [PATCH v4] " Changpeng Liu
2022-10-19  5:27       ` Xia, Chenbo
2022-10-26  9:24       ` Xia, Chenbo

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