[dpdk-dev] [PATCH v6 24/25] lib/librte_vhost: add TODO/FIXME for identified issues.

[Huawei Xie <huawei.xie@intel.com>]

1) FIXME:concurrent calls to vhost set mem table from different guests could cause mem_temp to be overrided.
2) TODO:cmpset cost quite some cpu cyles. allow app to disable this feature if there is no contention in real workload.
3) FIXME:fix scatter gather mbuf copy to vhost vring chained buffers

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 lib/librte_vhost/vhost-net-cdev.c | 1 +
 lib/librte_vhost/vhost_rxtx.c     | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/lib/librte_vhost/vhost-net-cdev.c b/lib/librte_vhost/vhost-net-cdev.c
index e5875eb..91ff0d8 100644
--- a/lib/librte_vhost/vhost-net-cdev.c
+++ b/lib/librte_vhost/vhost-net-cdev.c
@@ -214,6 +214,7 @@ vhost_net_ioctl(fuse_req_t req, int cmd, void *arg,
 		break;
 
 	case VHOST_SET_MEM_TABLE:
+		/*TODO fix race condition.*/
 		LOG_DEBUG(VHOST_CONFIG, "(%"PRIu64") IOCTL: VHOST_SET_MEM_TABLE\n", ctx.fh);
 		static struct vhost_memory mem_temp;
 
diff --git a/lib/librte_vhost/vhost_rxtx.c b/lib/librte_vhost/vhost_rxtx.c
index 2a1171a..84ec0e8 100644
--- a/lib/librte_vhost/vhost_rxtx.c
+++ b/lib/librte_vhost/vhost_rxtx.c
@@ -93,6 +93,7 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id,
 
 		res_end_idx = res_base_idx + count;
 		/* vq->last_used_idx_res is atomically updated. */
+		/* TODO: Allow to disable cmpset if no concurrency in application. */
 		success = rte_atomic16_cmpset(&vq->last_used_idx_res,
 				res_base_idx, res_end_idx);
 	} while (unlikely(success == 0));
@@ -146,6 +147,7 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id,
 		vq->used->ring[res_cur_idx & (vq->size - 1)].len = packet_len;
 
 		/* Copy mbuf data to buffer */
+		/* FIXME for sg mbuf and the case that desc couldn't hold the mbuf data */
 		rte_memcpy((void *)(uintptr_t)buff_addr,
 			rte_pktmbuf_mtod(buff, const void *),
 			rte_pktmbuf_data_len(buff));
-- 
1.8.1.4