On 2015/11/17 22:29, Yuanhan Liu wrote: > On Fri, Nov 13, 2015 at 02:20:30PM +0900, Tetsuya Mukawa wrote: >> These variables are needed to be able to manage one of virtio devices >> using both vhost library APIs and vhost PMD. >> For example, if vhost PMD uses current callback handler and private data >> provided by vhost library, A DPDK application that links vhost library >> cannot use some of vhost library APIs. > Can you be more specific about this? > > --yliu
How about like below? commit log: Currently, when virtio device is created and destroyed, vhost library will call one of callback handlers. The vhost PMD need to use this pair of callback handlers to know which virtio devices are connected actually. Because we can register only one pair of callbacks to vhost library, if the PMD use it, DPDK applications cannot have a way to know the events. This may break legacy DPDK applications that uses vhost library. To prevent it, this patch adds one more pair of callbacks to vhost library especially for the vhost PMD. With the patch, legacy applications can use the vhost PMD even if they need additional specific handling for virtio device creation and destruction. For example, legacy application can call rte_vhost_enable_guest_notification() in callbacks to change setting. Tetsuya
