[Qemu-devel] Re: [PATCH 7/7] trace: Trace virtqueue operations

[Avi Kivity]

On 05/25/2010 01:24 PM, Stefan Hajnoczi wrote:
> This patch adds trace events for virtqueue operations including
> adding/removing buffers, notifying the guest, and receiving a notify
> from the guest.
>
> diff --git a/trace-events b/trace-events
> index 48415f8..a533414 100644
> --- a/trace-events
> +++ b/trace-events
> @@ -35,6 +35,14 @@ qemu_memalign(size_t alignment, size_t size, void *ptr) 
> "alignment %zu size %zu
>   qemu_valloc(size_t size, void *ptr) "size %zu ptr %p"
>   qemu_vfree(void *ptr) "ptr %p"
>
> +# hw/virtio.c
> +virtqueue_fill(void *vq, const void *elem, unsigned int len, unsigned int idx) "vq 
> %p elem %p len %u idx %u"
> +virtqueue_flush(void *vq, unsigned int count) "vq %p count %u"
> +virtqueue_pop(void *vq, void *elem, unsigned int in_num, unsigned int out_num) "vq 
> %p elem %p in_num %u out_num %u"
> +virtio_queue_notify(void *vdev, int n, void *vq) "vdev %p n %d vq %p"
> +virtio_irq(void *vq) "vq %p"
> +virtio_notify(void *vdev, void *vq) "vdev %p vq %p"
> +
>    


Those %ps are more or less useless.  We need better ways of identifying 
them.

Linux uses %pTYPE to pretty print arbitrary types.  We could do 
something similar (not the same since we don't want our own printf 
implementation).

--
error compiling committee.c: too many arguments to function