doc: clean vhost async note

This patch moves the 'Recommended IOVA mode in async datapath'
section under 'Vhost asynchronous data path' as a sub-section,
which makes the doc cleaner.

Signed-off-by: Xuan Ding <xuan.ding@intel.com>
Reviewed-by: Jiayu Hu <jiayu.hu@intel.com>
Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>

diff --git a/doc/guides/prog_guide/vhost_lib.rst b/doc/guides/prog_guide/vhost_lib.rst
index 4d68b0e..a4ffed9 100644 (file)
--- a/doc/guides/prog_guide/vhost_lib.rst
+++ b/doc/guides/prog_guide/vhost_lib.rst
@@ -494,11 +494,11 @@ support sharing DMA channels among vrings.
   not poll completed will cause the DMA ring to be full, which will
   result in packet loss eventually.
 
-Recommended IOVA mode in async datapath
----------------------------------------
+* Recommended IOVA mode in async datapath
 
-When DMA devices are bound to VFIO driver, VA mode is recommended.
-For PA mode, page by page mapping may exceed IOMMU's max capability,
-better to use 1G guest hugepage.
+  When DMA devices are bound to VFIO driver, VA mode is recommended.
+  For PA mode, page by page mapping may exceed IOMMU's max capability,
+  better to use 1G guest hugepage.
 
-For UIO driver, any VFIO related error message can be ignored.
+  For UIO driver or kernel driver, any VFIO related error messages
+  can be ignored.