X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fvlib%2Fbuffer_funcs.h;h=cc56db7762ca1fece75fafef0e97b090346469fc;hb=75e7d1301475d49311d14e202936c62df0c07d10;hp=1ea3c0829b8f3b9440e1e11377ea6331ebb3feb4;hpb=cef87f1a5eb4d69cf11ce1cd3c5506edcfba74c4;p=vpp.git

diff --git a/src/vlib/buffer_funcs.h b/src/vlib/buffer_funcs.h
index 1ea3c0829b8..cc56db7762c 100644
--- a/src/vlib/buffer_funcs.h
+++ b/src/vlib/buffer_funcs.h
@@ -222,9 +222,9 @@ void vlib_buffer_validate_alloc_free (vlib_main_t * vm, u32 * buffers,
 				      expected_state);
 
 always_inline vlib_buffer_known_state_t
-vlib_buffer_is_known (vlib_main_t * vm, u32 buffer_index)
+vlib_buffer_is_known (u32 buffer_index)
 {
-  vlib_buffer_main_t *bm = vm->buffer_main;
+  vlib_buffer_main_t *bm = vlib_global_main.buffer_main;
 
   clib_spinlock_lock (&bm->buffer_known_hash_lockp);
   uword *p = hash_get (bm->buffer_known_hash, buffer_index);
@@ -233,11 +233,11 @@ vlib_buffer_is_known (vlib_main_t * vm, u32 buffer_index)
 }
 
 always_inline void
-vlib_buffer_set_known_state (vlib_main_t * vm,
-			     u32 buffer_index,
+vlib_buffer_set_known_state (u32 buffer_index,
 			     vlib_buffer_known_state_t state)
 {
-  vlib_buffer_main_t *bm = vm->buffer_main;
+  vlib_buffer_main_t *bm = vlib_global_main.buffer_main;
+
   clib_spinlock_lock (&bm->buffer_known_hash_lockp);
   hash_set (bm->buffer_known_hash, buffer_index, state);
   clib_spinlock_unlock (&bm->buffer_known_hash_lockp);
@@ -344,6 +344,35 @@ vlib_buffer_alloc (vlib_main_t * vm, u32 * buffers, u32 n_buffers)
 					   VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
 }
 
+/** \brief Allocate buffers into ring
+
+    @param vm - (vlib_main_t *) vlib main data structure pointer
+    @param buffers - (u32 * ) buffer index ring
+    @param start - (u32) first slot in the ring
+    @param ring_size - (u32) ring size
+    @param n_buffers - (u32) number of buffers requested
+    @return - (u32) number of buffers actually allocated, may be
+    less than the number requested or zero
+*/
+always_inline u32
+vlib_buffer_alloc_to_ring (vlib_main_t * vm, u32 * ring, u32 start,
+			   u32 ring_size, u32 n_buffers)
+{
+  u32 n_alloc;
+
+  ASSERT (n_buffers <= ring_size);
+
+  if (PREDICT_TRUE (start + n_buffers <= ring_size))
+    return vlib_buffer_alloc (vm, ring + start, n_buffers);
+
+  n_alloc = vlib_buffer_alloc (vm, ring + start, ring_size - start);
+
+  if (PREDICT_TRUE (n_alloc == ring_size - start))
+    n_alloc += vlib_buffer_alloc (vm, ring, n_buffers - n_alloc);
+
+  return n_alloc;
+}
+
 /** \brief Free buffers
     Frees the entire buffer chain for each buffer
 
@@ -975,6 +1004,68 @@ vlib_validate_buffer_set_in_use (vlib_buffer_t * b, u32 expected)
 #endif
 }
 
+/** minimum data size of first buffer in a buffer chain */
+#define VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE (256)
+
+/**
+ * @brief compress buffer chain in a way where the first buffer is at least
+ * VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE long
+ *
+ * @param[in] vm - vlib_main
+ * @param[in,out] first - first buffer in chain
+ * @param[in,out] discard_vector - vector of buffer indexes which were removed
+ * from the chain
+ */
+always_inline void
+vlib_buffer_chain_compress (vlib_main_t * vm,
+			    vlib_buffer_t * first, u32 ** discard_vector)
+{
+  if (first->current_length >= VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE ||
+      !(first->flags & VLIB_BUFFER_NEXT_PRESENT))
+    {
+      /* this is already big enough or not a chain */
+      return;
+    }
+  /* probe free list to find allocated buffer size to avoid overfill */
+  u32 index;
+  vlib_buffer_free_list_t *free_list =
+    vlib_buffer_get_buffer_free_list (vm, first, &index);
+
+  u32 want_first_size = clib_min (VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE,
+				  free_list->n_data_bytes -
+				  first->current_data);
+  do
+    {
+      vlib_buffer_t *second = vlib_get_buffer (vm, first->next_buffer);
+      u32 need = want_first_size - first->current_length;
+      u32 amount_to_copy = clib_min (need, second->current_length);
+      clib_memcpy (((u8 *) vlib_buffer_get_current (first)) +
+		   first->current_length,
+		   vlib_buffer_get_current (second), amount_to_copy);
+      first->current_length += amount_to_copy;
+      vlib_buffer_advance (second, amount_to_copy);
+      if (first->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID)
+	{
+	  first->total_length_not_including_first_buffer -= amount_to_copy;
+	}
+      if (!second->current_length)
+	{
+	  vec_add1 (*discard_vector, first->next_buffer);
+	  if (second->flags & VLIB_BUFFER_NEXT_PRESENT)
+	    {
+	      first->next_buffer = second->next_buffer;
+	    }
+	  else
+	    {
+	      first->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
+	    }
+	  second->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
+	}
+    }
+  while ((first->current_length < want_first_size) &&
+	 (first->flags & VLIB_BUFFER_NEXT_PRESENT));
+}
+
 #endif /* included_vlib_buffer_funcs_h */
 
 /*