#define VHOST_LOG_CACHE_NR 32
+#define PACKED_BATCH_SIZE (RTE_CACHE_LINE_SIZE / \
+ sizeof(struct vring_packed_desc))
+#define PACKED_BATCH_MASK (PACKED_BATCH_SIZE - 1)
+
+#ifdef VHOST_GCC_UNROLL_PRAGMA
+#define vhost_for_each_try_unroll(iter, val, size) _Pragma("GCC unroll 4") \
+ for (iter = val; iter < size; iter++)
+#endif
+
+#ifdef VHOST_CLANG_UNROLL_PRAGMA
+#define vhost_for_each_try_unroll(iter, val, size) _Pragma("unroll 4") \
+ for (iter = val; iter < size; iter++)
+#endif
+
+#ifdef VHOST_ICC_UNROLL_PRAGMA
+#define vhost_for_each_try_unroll(iter, val, size) _Pragma("unroll (4)") \
+ for (iter = val; iter < size; iter++)
+#endif
+
+#ifndef vhost_for_each_try_unroll
+#define vhost_for_each_try_unroll(iter, val, num) \
+ for (iter = val; iter < num; iter++)
+#endif
+
/**
* Structure contains buffer address, length and descriptor index
* from vring to do scatter RX.