vcl: add apis that expos fifo as buffer

[vpp.git] / src / svm / svm_fifo.c

diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c
index dbdb813..0c258b4 100644 (file)
--- a/src/svm/svm_fifo.c
+++ b/src/svm/svm_fifo.c
@@ -174,11 +174,12 @@ format_svm_fifo (u8 * s, va_list * args)
 
   s = format (s, "cursize %u nitems %u has_event %d\n",
              f->cursize, f->nitems, f->has_event);
-  s = format (s, " head %d tail %d\n", f->head, f->tail);
+  s = format (s, " head %d tail %d segment manager %u\n", f->head, f->tail,
+             f->segment_manager);
 
   if (verbose > 1)
     s = format
-      (s, " server session %d thread %d client session %d thread %d\n",
+      (s, " vpp session %d thread %d app session %d thread %d\n",
        f->master_session_index, f->master_thread_index,
        f->client_session_index, f->client_thread_index);
 
@@ -827,6 +828,60 @@ svm_fifo_dequeue_drop (svm_fifo_t * f, u32 max_bytes)
   return total_drop_bytes;
 }
 
+void
+svm_fifo_dequeue_drop_all (svm_fifo_t * f)
+{
+  f->head = f->tail;
+  __sync_fetch_and_sub (&f->cursize, f->cursize);
+}
+
+int
+svm_fifo_segments (svm_fifo_t * f, svm_fifo_segment_t * fs)
+{
+  u32 cursize, nitems;
+
+  /* read cursize, which can only increase while we're working */
+  cursize = svm_fifo_max_dequeue (f);
+  if (PREDICT_FALSE (cursize == 0))
+    return -2;
+
+  nitems = f->nitems;
+
+  fs[0].len = ((nitems - f->head) < cursize) ? (nitems - f->head) : cursize;
+  fs[0].data = f->data + f->head;
+
+  if (fs[0].len < cursize)
+    {
+      fs[1].len = cursize - fs[0].len;
+      fs[1].data = f->data;
+    }
+  else
+    {
+      fs[1].len = 0;
+      fs[1].data = 0;
+    }
+  return cursize;
+}
+
+void
+svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_segment_t * fs)
+{
+  u32 total_drop_bytes;
+
+  ASSERT (fs[0].data == f->data + f->head);
+  if (fs[1].len)
+    {
+      f->head = fs[1].len;
+      total_drop_bytes = fs[0].len + fs[1].len;
+    }
+  else
+    {
+      f->head = (f->head + fs[0].len) % f->nitems;
+      total_drop_bytes = fs[0].len;
+    }
+  __sync_fetch_and_sub (&f->cursize, total_drop_bytes);
+}
+
 u32
 svm_fifo_number_ooo_segments (svm_fifo_t * f)
 {