Commit 4d6a105e authored by Tiwei Bie's avatar Tiwei Bie Committed by David S. Miller
Browse files

virtio_ring: introduce debug helpers 



Introduce debug helpers for last_add_time update, check and
invalid. They will be used by packed ring too.

Signed-off-by: default avatarTiwei Bie <tiwei.bie@intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e593bf97

drivers/virtio/virtio_ring.c

+27 −22
Original line number Diff line number Diff line
@@ -44,6 +44,26 @@ 
	} while (0)

#define END_USE(_vq) \

	do { BUG_ON(!(_vq)->in_use); (_vq)->in_use = 0; } while(0)

#define LAST_ADD_TIME_UPDATE(_vq)				\

	do {							\

		ktime_t now = ktime_get();			\

								\

		/* No kick or get, with .1 second between?  Warn. */ \

		if ((_vq)->last_add_time_valid)			\

			WARN_ON(ktime_to_ms(ktime_sub(now,	\

				(_vq)->last_add_time)) > 100);	\

		(_vq)->last_add_time = now;			\

		(_vq)->last_add_time_valid = true;		\

	} while (0)

#define LAST_ADD_TIME_CHECK(_vq)				\

	do {							\

		if ((_vq)->last_add_time_valid) {		\

			WARN_ON(ktime_to_ms(ktime_sub(ktime_get(), \

				      (_vq)->last_add_time)) > 100); \

		}						\

	} while (0)

#define LAST_ADD_TIME_INVALID(_vq)				\

	((_vq)->last_add_time_valid = false)

#else

#define BAD_RING(_vq, fmt, args...)				\

	do {							\
@@ -53,6 +73,9 @@ 
	} while (0)

#define START_USE(vq)

#define END_USE(vq)

#define LAST_ADD_TIME_UPDATE(vq)

#define LAST_ADD_TIME_CHECK(vq)

#define LAST_ADD_TIME_INVALID(vq)

#endif



struct vring_desc_state {
@@ -295,18 +318,7 @@ static inline int virtqueue_add_split(struct virtqueue *_vq, 
		return -EIO;

	}



#ifdef DEBUG

	{

		ktime_t now = ktime_get();



		/* No kick or get, with .1 second between?  Warn. */

		if (vq->last_add_time_valid)

			WARN_ON(ktime_to_ms(ktime_sub(now, vq->last_add_time))

					    > 100);

		vq->last_add_time = now;

		vq->last_add_time_valid = true;

	}

#endif

	LAST_ADD_TIME_UPDATE(vq);



	BUG_ON(total_sg == 0);
@@ -467,13 +479,8 @@ static bool virtqueue_kick_prepare_split(struct virtqueue *_vq) 
	new = vq->split.avail_idx_shadow;

	vq->num_added = 0;



#ifdef DEBUG

	if (vq->last_add_time_valid) {

		WARN_ON(ktime_to_ms(ktime_sub(ktime_get(),

					      vq->last_add_time)) > 100);

	}

	vq->last_add_time_valid = false;

#endif

	LAST_ADD_TIME_CHECK(vq);

	LAST_ADD_TIME_INVALID(vq);



	if (vq->event) {

		needs_kick = vring_need_event(virtio16_to_cpu(_vq->vdev,
@@ -597,9 +604,7 @@ static void *virtqueue_get_buf_ctx_split(struct virtqueue *_vq, 
				&vring_used_event(&vq->split.vring),

				cpu_to_virtio16(_vq->vdev, vq->last_used_idx));



#ifdef DEBUG

	vq->last_add_time_valid = false;

#endif

	LAST_ADD_TIME_INVALID(vq);



	END_USE(vq);

	return ret;