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: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 0b97e5c..10d4079 100644 (file)
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -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;