[dpdk-stable] [PATCH] examples/vhost: fix ioat ring space in callbacks

[Cheng Jiang <Cheng1.jiang@intel.com>]

We use ioat ring space for determining if ioat callbacks can enqueue a
packet to ioat device. But there is one slot can't be used in ioat
ring due to the ioat driver design, so we need to reduce one slot in
ioat ring to prevent ring size mismatch in ioat callbacks.

Fixes: 2aa47e94bfb2 ("examples/vhost: add ioat ring space count and check")
Cc: stable@dpdk.org

Signed-off-by: Cheng Jiang <Cheng1.jiang@intel.com>
---
 examples/vhost/ioat.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/examples/vhost/ioat.c b/examples/vhost/ioat.c
index 60b73be93..9cb5e0d50 100644
--- a/examples/vhost/ioat.c
+++ b/examples/vhost/ioat.c
@@ -113,7 +113,7 @@ open_ioat(const char *value)
 			goto out;
 		}
 		rte_rawdev_start(dev_id);
-		cb_tracker[dev_id].ioat_space = IOAT_RING_SIZE;
+		cb_tracker[dev_id].ioat_space = IOAT_RING_SIZE - 1;
 		dma_info->nr++;
 		i++;
 	}
-- 
2.29.2