VPP-598: tcp stack initial commit

Change-Id: I49e5ce0aae6e4ff634024387ceaf7dbc432a0351
Signed-off-by: Dave Barach <dave@barachs.net>
Signed-off-by: Florin Coras <fcoras@cisco.com>

7 files changed, 1395 insertions, 7 deletions

diff --git a/src/svm/ssvm.c b/src/svm/ssvm.c
index 6f409eb6..6cda1f27 100644
--- a/src/svm/ssvm.c
+++ b/src/svm/ssvm.c
@@ -169,6 +169,22 @@ re_map_it:
   return 0;
 }
 
+void
+ssvm_delete (ssvm_private_t * ssvm)
+{
+  u8 *fn;
+
+  fn = format (0, "/dev/shm/%s%c", ssvm->name, 0);
+
+  /* Throw away the backing file */
+  if (unlink ((char *) fn) < 0)
+    clib_unix_warning ("unlink segment '%s'", ssvm->name);
+
+  munmap ((void *) ssvm->requested_va, ssvm->ssvm_size);
+  vec_free (fn);
+}
+
+
 /*
  * fd.io coding-style-patch-verification: ON
  *
diff --git a/src/svm/ssvm.h b/src/svm/ssvm.h
index 9e61b9a0..bccfc164 100644
--- a/src/svm/ssvm.h
+++ b/src/svm/ssvm.h
@@ -38,7 +38,10 @@
 #include <vppinfra/pool.h>
 #include <vppinfra/format.h>
 
-#define MMAP_PAGESIZE (4<<10)
+#ifndef MMAP_PAGESIZE
+#define MMAP_PAGESIZE (clib_mem_get_page_size())
+#endif
+
 #define SSVM_N_OPAQUE 7
 
 typedef struct
@@ -125,12 +128,12 @@ ssvm_pop_heap (void *oldheap)
 }
 
 #define foreach_ssvm_api_error                  \
-_(NO_NAME, "No shared segment name", -10)       \
-_(NO_SIZE, "Size not set (master)", -11)        \
-_(CREATE_FAILURE, "Create failed", -12)		\
-_(SET_SIZE, "Set size failed", -13)		\
-_(MMAP, "mmap failed", -14)			\
-_(SLAVE_TIMEOUT, "Slave map timeout", -15)
+_(NO_NAME, "No shared segment name", -100)      \
+_(NO_SIZE, "Size not set (master)", -101)       \
+_(CREATE_FAILURE, "Create failed", -102)        \
+_(SET_SIZE, "Set size failed", -103)		\
+_(MMAP, "mmap failed", -104)			\
+_(SLAVE_TIMEOUT, "Slave map timeout", -105)
 
 typedef enum
 {
@@ -143,6 +146,7 @@ typedef enum
 
 int ssvm_master_init (ssvm_private_t * ssvm, u32 master_index);
 int ssvm_slave_init (ssvm_private_t * ssvm, int timeout_in_seconds);
+void ssvm_delete (ssvm_private_t * ssvm);
 
 #endif /* __included_ssvm_h__ */
 
diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c
new file mode 100644
index 00000000..11f90193
--- /dev/null
+++ b/src/svm/svm_fifo.c
@@ -0,0 +1,568 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "svm_fifo.h"
+
+/** create an svm fifo, in the current heap. Fails vs blow up the process */
+svm_fifo_t *
+svm_fifo_create (u32 data_size_in_bytes)
+{
+  svm_fifo_t *f;
+  pthread_mutexattr_t attr;
+  pthread_condattr_t cattr;
+
+  f = clib_mem_alloc_aligned_or_null (sizeof (*f) + data_size_in_bytes,
+				      CLIB_CACHE_LINE_BYTES);
+  if (f == 0)
+    return 0;
+
+  memset (f, 0, sizeof (*f) + data_size_in_bytes);
+  f->nitems = data_size_in_bytes;
+  f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX;
+
+  memset (&attr, 0, sizeof (attr));
+  memset (&cattr, 0, sizeof (cattr));
+
+  if (pthread_mutexattr_init (&attr))
+    clib_unix_warning ("mutexattr_init");
+  if (pthread_mutexattr_setpshared (&attr, PTHREAD_PROCESS_SHARED))
+    clib_unix_warning ("pthread_mutexattr_setpshared");
+  if (pthread_mutex_init (&f->mutex, &attr))
+    clib_unix_warning ("mutex_init");
+  if (pthread_mutexattr_destroy (&attr))
+    clib_unix_warning ("mutexattr_destroy");
+  if (pthread_condattr_init (&cattr))
+    clib_unix_warning ("condattr_init");
+  if (pthread_condattr_setpshared (&cattr, PTHREAD_PROCESS_SHARED))
+    clib_unix_warning ("condattr_setpshared");
+  if (pthread_cond_init (&f->condvar, &cattr))
+    clib_unix_warning ("cond_init1");
+  if (pthread_condattr_destroy (&cattr))
+    clib_unix_warning ("cond_init2");
+
+  return (f);
+}
+
+always_inline ooo_segment_t *
+ooo_segment_new (svm_fifo_t * f, u32 start, u32 length)
+{
+  ooo_segment_t *s;
+
+  pool_get (f->ooo_segments, s);
+
+  s->fifo_position = start;
+  s->length = length;
+
+  s->prev = s->next = OOO_SEGMENT_INVALID_INDEX;
+
+  return s;
+}
+
+always_inline void
+ooo_segment_del (svm_fifo_t * f, u32 index)
+{
+  ooo_segment_t *cur, *prev = 0, *next = 0;
+  cur = pool_elt_at_index (f->ooo_segments, index);
+
+  if (cur->next != OOO_SEGMENT_INVALID_INDEX)
+    {
+      next = pool_elt_at_index (f->ooo_segments, cur->next);
+      next->prev = cur->prev;
+    }
+
+  if (cur->prev != OOO_SEGMENT_INVALID_INDEX)
+    {
+      prev = pool_elt_at_index (f->ooo_segments, cur->prev);
+      prev->next = cur->next;
+    }
+  else
+    {
+      f->ooos_list_head = cur->next;
+    }
+
+  pool_put (f->ooo_segments, cur);
+}
+
+/**
+ * Add segment to fifo's out-of-order segment list. Takes care of merging
+ * adjacent segments and removing overlapping ones.
+ */
+static void
+ooo_segment_add (svm_fifo_t * f, u32 offset, u32 length)
+{
+  ooo_segment_t *s, *new_s, *prev, *next, *it;
+  u32 new_index, position, end_offset, s_sof, s_eof, s_index;
+
+  position = (f->tail + offset) % f->nitems;
+  end_offset = offset + length;
+
+  if (f->ooos_list_head == OOO_SEGMENT_INVALID_INDEX)
+    {
+      s = ooo_segment_new (f, position, length);
+      f->ooos_list_head = s - f->ooo_segments;
+      f->ooos_newest = f->ooos_list_head;
+      return;
+    }
+
+  /* Find first segment that starts after new segment */
+  s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
+  while (s->next != OOO_SEGMENT_INVALID_INDEX
+	 && ooo_segment_offset (f, s) <= offset)
+    s = pool_elt_at_index (f->ooo_segments, s->next);
+
+  s_index = s - f->ooo_segments;
+  s_sof = ooo_segment_offset (f, s);
+  s_eof = ooo_segment_end_offset (f, s);
+
+  /* No overlap, add before current segment */
+  if (end_offset < s_sof)
+    {
+      new_s = ooo_segment_new (f, position, length);
+      new_index = new_s - f->ooo_segments;
+
+      /* Pool might've moved, get segment again */
+      s = pool_elt_at_index (f->ooo_segments, s_index);
+
+      if (s->prev != OOO_SEGMENT_INVALID_INDEX)
+	{
+	  new_s->prev = s->prev;
+
+	  prev = pool_elt_at_index (f->ooo_segments, new_s->prev);
+	  prev->next = new_index;
+	}
+      else
+	{
+	  /* New head */
+	  f->ooos_list_head = new_index;
+	}
+
+      new_s->next = s - f->ooo_segments;
+      s->prev = new_index;
+      f->ooos_newest = new_index;
+      return;
+    }
+  /* No overlap, add after current segment */
+  else if (s_eof < offset)
+    {
+      new_s = ooo_segment_new (f, position, length);
+      new_index = new_s - f->ooo_segments;
+
+      /* Pool might've moved, get segment again */
+      s = pool_elt_at_index (f->ooo_segments, s_index);
+
+      if (s->next != OOO_SEGMENT_INVALID_INDEX)
+	{
+	  new_s->next = s->next;
+
+	  next = pool_elt_at_index (f->ooo_segments, new_s->next);
+	  next->prev = new_index;
+	}
+
+      new_s->prev = s - f->ooo_segments;
+      s->next = new_index;
+      f->ooos_newest = new_index;
+
+      return;
+    }
+
+  /*
+   * Merge needed
+   */
+
+  /* Merge at head */
+  if (offset <= s_sof)
+    {
+      /* If we have a previous, check if we overlap */
+      if (s->prev != OOO_SEGMENT_INVALID_INDEX)
+	{
+	  prev = pool_elt_at_index (f->ooo_segments, s->prev);
+
+	  /* New segment merges prev and current. Remove previous and
+	   * update position of current. */
+	  if (ooo_segment_end_offset (f, prev) >= offset)
+	    {
+	      s->fifo_position = prev->fifo_position;
+	      s->length = s_eof - ooo_segment_offset (f, prev);
+	      ooo_segment_del (f, s->prev);
+	    }
+	}
+      else
+	{
+	  s->fifo_position = position;
+	  s->length = s_eof - ooo_segment_offset (f, s);
+	}
+
+      /* The new segment's tail may cover multiple smaller ones */
+      if (s_eof < end_offset)
+	{
+	  /* Remove segments completely covered */
+	  it = (s->next != OOO_SEGMENT_INVALID_INDEX) ?
+	    pool_elt_at_index (f->ooo_segments, s->next) : 0;
+	  while (it && ooo_segment_end_offset (f, it) < end_offset)
+	    {
+	      next = (it->next != OOO_SEGMENT_INVALID_INDEX) ?
+		pool_elt_at_index (f->ooo_segments, it->next) : 0;
+	      ooo_segment_del (f, it - f->ooo_segments);
+	      it = next;
+	    }
+
+	  /* Update length. Segment's start might have changed. */
+	  s->length = end_offset - ooo_segment_offset (f, s);
+
+	  /* If partial overlap with last, merge */
+	  if (it && ooo_segment_offset (f, it) < end_offset)
+	    {
+	      s->length +=
+		it->length - (ooo_segment_offset (f, it) - end_offset);
+	      ooo_segment_del (f, it - f->ooo_segments);
+	    }
+	}
+    }
+  /* Last but overlapping previous */
+  else if (s_eof <= end_offset)
+    {
+      s->length = end_offset - ooo_segment_offset (f, s);
+    }
+  /* New segment completely covered by current one */
+  else
+    {
+      /* Do Nothing */
+    }
+
+  /* Most recently updated segment */
+  f->ooos_newest = s - f->ooo_segments;
+}
+
+/**
+ * Removes segments that can now be enqueued because the fifo's tail has
+ * advanced. Returns the number of bytes added to tail.
+ */
+static int
+ooo_segment_try_collect (svm_fifo_t * f, u32 n_bytes_enqueued)
+{
+  ooo_segment_t *s;
+  u32 index, bytes = 0, diff;
+
+  s = pool_elt_at_index (f->ooo_segments, f->ooos_list_head);
+
+  /* If last tail update overlaps one/multiple ooo segments, remove them */
+  diff = (f->nitems + f->tail - s->fifo_position) % f->nitems;
+  while (0 < diff && diff < n_bytes_enqueued)
+    {
+      /* Segment end is beyond the tail. Advance tail and be done */
+      if (diff < s->length)
+	{
+	  f->tail += s->length - diff;
+	  f->tail %= f->nitems;
+	  break;
+	}
+      /* If we have next go on */
+      else if (s->next != OOO_SEGMENT_INVALID_INDEX)
+	{
+	  index = s - f->ooo_segments;
+	  s = pool_elt_at_index (f->ooo_segments, s->next);
+	  diff = (f->nitems + f->tail - s->fifo_position) % f->nitems;
+	  ooo_segment_del (f, index);
+	}
+      /* End of search */
+      else
+	{
+	  break;
+	}
+    }
+
+  /* If tail is adjacent to an ooo segment, 'consume' it */
+  if (diff == 0)
+    {
+      bytes = ((f->nitems - f->cursize) >= s->length) ? s->length :
+	f->nitems - f->cursize;
+
+      f->tail += bytes;
+      f->tail %= f->nitems;
+
+      ooo_segment_del (f, s - f->ooo_segments);
+    }
+
+  return bytes;
+}
+
+static int
+svm_fifo_enqueue_internal (svm_fifo_t * f,
+			   int pid, u32 max_bytes, u8 * copy_from_here)
+{
+  u32 total_copy_bytes, first_copy_bytes, second_copy_bytes;
+  u32 cursize, nitems;
+
+  if (PREDICT_FALSE (f->cursize == f->nitems))
+    return -2;			/* fifo stuffed */
+
+  /* read cursize, which can only decrease while we're working */
+  cursize = f->cursize;
+  nitems = f->nitems;
+
+  /* Number of bytes we're going to copy */
+  total_copy_bytes = (nitems - cursize) < max_bytes ?
+    (nitems - cursize) : max_bytes;
+
+  if (PREDICT_TRUE (copy_from_here != 0))
+    {
+      /* Number of bytes in first copy segment */
+      first_copy_bytes = ((nitems - f->tail) < total_copy_bytes)
+	? (nitems - f->tail) : total_copy_bytes;
+
+      clib_memcpy (&f->data[f->tail], copy_from_here, first_copy_bytes);
+      f->tail += first_copy_bytes;
+      f->tail = (f->tail == nitems) ? 0 : f->tail;
+
+      /* Number of bytes in second copy segment, if any */
+      second_copy_bytes = total_copy_bytes - first_copy_bytes;
+      if (second_copy_bytes)
+	{
+	  clib_memcpy (&f->data[f->tail], copy_from_here + first_copy_bytes,
+		       second_copy_bytes);
+	  f->tail += second_copy_bytes;
+	  f->tail = (f->tail == nitems) ? 0 : f->tail;
+	}
+    }
+  else
+    {
+      /* Account for a zero-copy enqueue done elsewhere */
+      ASSERT (max_bytes <= (nitems - cursize));
+      f->tail += max_bytes;
+      f->tail = f->tail % nitems;
+      total_copy_bytes = max_bytes;
+    }
+
+  /* Any out-of-order segments to collect? */
+  if (PREDICT_FALSE (f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX))
+    total_copy_bytes += ooo_segment_try_collect (f, total_copy_bytes);
+
+  /* Atomically increase the queue length */
+  __sync_fetch_and_add (&f->cursize, total_copy_bytes);
+
+  return (total_copy_bytes);
+}
+
+int
+svm_fifo_enqueue_nowait (svm_fifo_t * f,
+			 int pid, u32 max_bytes, u8 * copy_from_here)
+{
+  return svm_fifo_enqueue_internal (f, pid, max_bytes, copy_from_here);
+}
+
+/** Enqueue a future segment.
+ * Two choices: either copies the entire segment, or copies nothing
+ * Returns 0 of the entire segment was copied
+ * Returns -1 if none of the segment was copied due to lack of space
+ */
+
+static int
+svm_fifo_enqueue_with_offset_internal2 (svm_fifo_t * f,
+					int pid,
+					u32 offset,
+					u32 required_bytes,
+					u8 * copy_from_here)
+{
+  u32 total_copy_bytes, first_copy_bytes, second_copy_bytes;
+  u32 cursize, nitems;
+  u32 tail_plus_offset;
+
+  ASSERT (offset > 0);
+
+  /* read cursize, which can only decrease while we're working */
+  cursize = f->cursize;
+  nitems = f->nitems;
+
+  /* Will this request fit? */
+  if ((required_bytes + offset) > (nitems - cursize))
+    return -1;
+
+  ooo_segment_add (f, offset, required_bytes);
+
+  /* Number of bytes we're going to copy */
+  total_copy_bytes = required_bytes;
+  tail_plus_offset = (f->tail + offset) % nitems;
+
+  /* Number of bytes in first copy segment */
+  first_copy_bytes = ((nitems - tail_plus_offset) < total_copy_bytes)
+    ? (nitems - tail_plus_offset) : total_copy_bytes;
+
+  clib_memcpy (&f->data[tail_plus_offset], copy_from_here, first_copy_bytes);
+
+  /* Number of bytes in second copy segment, if any */
+  second_copy_bytes = total_copy_bytes - first_copy_bytes;
+  if (second_copy_bytes)
+    {
+      tail_plus_offset += first_copy_bytes;
+      tail_plus_offset %= nitems;
+
+      ASSERT (tail_plus_offset == 0);
+
+      clib_memcpy (&f->data[tail_plus_offset],
+		   copy_from_here + first_copy_bytes, second_copy_bytes);
+    }
+
+  return (0);
+}
+
+
+int
+svm_fifo_enqueue_with_offset (svm_fifo_t * f,
+			      int pid,
+			      u32 offset,
+			      u32 required_bytes, u8 * copy_from_here)
+{
+  return svm_fifo_enqueue_with_offset_internal2
+    (f, pid, offset, required_bytes, copy_from_here);
+}
+
+
+static int
+svm_fifo_dequeue_internal2 (svm_fifo_t * f,
+			    int pid, u32 max_bytes, u8 * copy_here)
+{
+  u32 total_copy_bytes, first_copy_bytes, second_copy_bytes;
+  u32 cursize, nitems;
+
+  if (PREDICT_FALSE (f->cursize == 0))
+    return -2;			/* nothing in the fifo */
+
+  /* read cursize, which can only increase while we're working */
+  cursize = f->cursize;
+  nitems = f->nitems;
+
+  /* Number of bytes we're going to copy */
+  total_copy_bytes = (cursize < max_bytes) ? cursize : max_bytes;
+
+  if (PREDICT_TRUE (copy_here != 0))
+    {
+      /* Number of bytes in first copy segment */
+      first_copy_bytes = ((nitems - f->head) < total_copy_bytes)
+	? (nitems - f->head) : total_copy_bytes;
+      clib_memcpy (copy_here, &f->data[f->head], first_copy_bytes);
+      f->head += first_copy_bytes;
+      f->head = (f->head == nitems) ? 0 : f->head;
+
+      /* Number of bytes in second copy segment, if any */
+      second_copy_bytes = total_copy_bytes - first_copy_bytes;
+      if (second_copy_bytes)
+	{
+	  clib_memcpy (copy_here + first_copy_bytes,
+		       &f->data[f->head], second_copy_bytes);
+	  f->head += second_copy_bytes;
+	  f->head = (f->head == nitems) ? 0 : f->head;
+	}
+    }
+  else
+    {
+      /* Account for a zero-copy dequeue done elsewhere */
+      ASSERT (max_bytes <= cursize);
+      f->head += max_bytes;
+      f->head = f->head % nitems;
+      cursize -= max_bytes;
+      total_copy_bytes = max_bytes;
+    }
+
+  __sync_fetch_and_sub (&f->cursize, total_copy_bytes);
+
+  return (total_copy_bytes);
+}
+
+int
+svm_fifo_dequeue_nowait (svm_fifo_t * f,
+			 int pid, u32 max_bytes, u8 * copy_here)
+{
+  return svm_fifo_dequeue_internal2 (f, pid, max_bytes, copy_here);
+}
+
+int
+svm_fifo_peek (svm_fifo_t * f, int pid, u32 offset, u32 max_bytes,
+	       u8 * copy_here)
+{
+  u32 total_copy_bytes, first_copy_bytes, second_copy_bytes;
+  u32 cursize, nitems;
+
+  if (PREDICT_FALSE (f->cursize == 0))
+    return -2;			/* nothing in the fifo */
+
+  /* read cursize, which can only increase while we're working */
+  cursize = f->cursize;
+  nitems = f->nitems;
+
+  /* Number of bytes we're going to copy */
+  total_copy_bytes = (cursize < max_bytes) ? cursize : max_bytes;
+
+  if (PREDICT_TRUE (copy_here != 0))
+    {
+      /* Number of bytes in first copy segment */
+      first_copy_bytes =
+	((nitems - f->head) < total_copy_bytes) ?
+	(nitems - f->head) : total_copy_bytes;
+      clib_memcpy (copy_here, &f->data[f->head], first_copy_bytes);
+
+      /* Number of bytes in second copy segment, if any */
+      second_copy_bytes = total_copy_bytes - first_copy_bytes;
+      if (second_copy_bytes)
+	{
+	  clib_memcpy (copy_here + first_copy_bytes, &f->data[0],
+		       second_copy_bytes);
+	}
+    }
+  return total_copy_bytes;
+}
+
+int
+svm_fifo_dequeue_drop (svm_fifo_t * f, int pid, u32 max_bytes)
+{
+  u32 total_drop_bytes, first_drop_bytes, second_drop_bytes;
+  u32 cursize, nitems;
+
+  if (PREDICT_FALSE (f->cursize == 0))
+    return -2;			/* nothing in the fifo */
+
+  /* read cursize, which can only increase while we're working */
+  cursize = f->cursize;
+  nitems = f->nitems;
+
+  /* Number of bytes we're going to drop */
+  total_drop_bytes = (cursize < max_bytes) ? cursize : max_bytes;
+
+  /* Number of bytes in first copy segment */
+  first_drop_bytes =
+    ((nitems - f->head) < total_drop_bytes) ?
+    (nitems - f->head) : total_drop_bytes;
+  f->head += first_drop_bytes;
+  f->head = (f->head == nitems) ? 0 : f->head;
+
+  /* Number of bytes in second drop segment, if any */
+  second_drop_bytes = total_drop_bytes - first_drop_bytes;
+  if (second_drop_bytes)
+    {
+      f->head += second_drop_bytes;
+      f->head = (f->head == nitems) ? 0 : f->head;
+    }
+
+  __sync_fetch_and_sub (&f->cursize, total_drop_bytes);
+
+  return total_drop_bytes;
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/svm/svm_fifo.h b/src/svm/svm_fifo.h
new file mode 100644
index 00000000..70624b74
--- /dev/null
+++ b/src/svm/svm_fifo.h
@@ -0,0 +1,157 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef __included_ssvm_fifo_h__
+#define __included_ssvm_fifo_h__
+
+#include <vppinfra/clib.h>
+#include <vppinfra/vec.h>
+#include <vppinfra/mheap.h>
+#include <vppinfra/heap.h>
+#include <vppinfra/pool.h>
+#include <vppinfra/format.h>
+#include <pthread.h>
+
+typedef enum
+{
+  SVM_FIFO_TAG_NOT_HELD = 0,
+  SVM_FIFO_TAG_DEQUEUE,
+  SVM_FIFO_TAG_ENQUEUE,
+} svm_lock_tag_t;
+
+/** Out-of-order segment */
+typedef struct
+{
+  u32 next;	/**< Next linked-list element pool index */
+  u32 prev;	/**< Previous linked-list element pool index */
+
+  u32 fifo_position;	/**< Start of segment, normalized*/
+  u32 length;		/**< Length of segment */
+} ooo_segment_t;
+
+#define OOO_SEGMENT_INVALID_INDEX ((u32)~0)
+
+typedef struct
+{
+  pthread_mutex_t mutex;	/* 8 bytes */
+  pthread_cond_t condvar;	/* 8 bytes */
+  u32 owner_pid;
+  svm_lock_tag_t tag;
+  volatile u32 cursize;
+  u32 nitems;
+
+  /* Backpointers */
+  u32 server_session_index;
+  u32 client_session_index;
+  u8 server_thread_index;
+  u8 client_thread_index;
+    CLIB_CACHE_LINE_ALIGN_MARK (end_shared);
+  u32 head;
+    CLIB_CACHE_LINE_ALIGN_MARK (end_consumer);
+
+  /* producer */
+  u32 tail;
+
+  ooo_segment_t *ooo_segments;	/**< Pool of ooo segments */
+  u32 ooos_list_head;		/**< Head of out-of-order linked-list */
+  u32 ooos_newest;		/**< Last segment to have been updated */
+
+    CLIB_CACHE_LINE_ALIGN_MARK (data);
+} svm_fifo_t;
+
+static inline int
+svm_fifo_lock (svm_fifo_t * f, u32 pid, u32 tag, int nowait)
+{
+  if (PREDICT_TRUE (nowait == 0))
+    pthread_mutex_lock (&f->mutex);
+  else
+    {
+      if (pthread_mutex_trylock (&f->mutex))
+	return -1;
+    }
+  f->owner_pid = pid;
+  f->tag = tag;
+  return 0;
+}
+
+static inline void
+svm_fifo_unlock (svm_fifo_t * f)
+{
+  f->owner_pid = 0;
+  f->tag = 0;
+  CLIB_MEMORY_BARRIER ();
+  pthread_mutex_unlock (&f->mutex);
+}
+
+static inline u32
+svm_fifo_max_dequeue (svm_fifo_t * f)
+{
+  return f->cursize;
+}
+
+static inline u32
+svm_fifo_max_enqueue (svm_fifo_t * f)
+{
+  return f->nitems - f->cursize;
+}
+
+static inline u8
+svm_fifo_has_ooo_data (svm_fifo_t * f)
+{
+  return f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX;
+}
+
+svm_fifo_t *svm_fifo_create (u32 data_size_in_bytes);
+
+int svm_fifo_enqueue_nowait (svm_fifo_t * f, int pid, u32 max_bytes,
+			     u8 * copy_from_here);
+
+int svm_fifo_enqueue_with_offset (svm_fifo_t * f, int pid,
+				  u32 offset, u32 required_bytes,
+				  u8 * copy_from_here);
+
+int svm_fifo_dequeue_nowait (svm_fifo_t * f, int pid, u32 max_bytes,
+			     u8 * copy_here);
+
+int svm_fifo_peek (svm_fifo_t * f, int pid, u32 offset, u32 max_bytes,
+		   u8 * copy_here);
+int svm_fifo_dequeue_drop (svm_fifo_t * f, int pid, u32 max_bytes);
+
+always_inline ooo_segment_t *
+svm_fifo_newest_ooo_segment (svm_fifo_t * f)
+{
+  return f->ooo_segments + f->ooos_newest;
+}
+
+always_inline u32
+ooo_segment_offset (svm_fifo_t * f, ooo_segment_t * s)
+{
+  return ((f->nitems + s->fifo_position - f->tail) % f->nitems);
+}
+
+always_inline u32
+ooo_segment_end_offset (svm_fifo_t * f, ooo_segment_t * s)
+{
+  return ((f->nitems + s->fifo_position + s->length - f->tail) % f->nitems);
+}
+
+#endif /* __included_ssvm_fifo_h__ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/svm/svm_fifo_segment.c b/src/svm/svm_fifo_segment.c
new file mode 100644
index 00000000..acabb3bd
--- /dev/null
+++ b/src/svm/svm_fifo_segment.c
@@ -0,0 +1,193 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <svm/svm_fifo_segment.h>
+
+svm_fifo_segment_main_t svm_fifo_segment_main;
+
+/** (master) create an svm fifo segment */
+int
+svm_fifo_segment_create (svm_fifo_segment_create_args_t * a)
+{
+  int rv;
+  svm_fifo_segment_private_t *s;
+  svm_fifo_segment_main_t *sm = &svm_fifo_segment_main;
+  ssvm_shared_header_t *sh;
+  svm_fifo_segment_header_t *fsh;
+  void *oldheap;
+
+  /* Allocate a fresh segment */
+  pool_get (sm->segments, s);
+  memset (s, 0, sizeof (*s));
+
+  s->ssvm.ssvm_size = a->segment_size;
+  s->ssvm.i_am_master = 1;
+  s->ssvm.my_pid = getpid ();
+  s->ssvm.name = (u8 *) a->segment_name;
+  s->ssvm.requested_va = sm->next_baseva;
+
+  rv = ssvm_master_init (&s->ssvm, s - sm->segments);
+
+  if (rv)
+    {
+      _vec_len (s) = vec_len (s) - 1;
+      return (rv);
+    }
+
+  /* Note; requested_va updated due to seg base addr randomization */
+  sm->next_baseva = s->ssvm.requested_va + a->segment_size;
+
+  sh = s->ssvm.sh;
+  oldheap = ssvm_push_heap (sh);
+
+  /* Set up svm_fifo_segment shared header */
+  fsh = clib_mem_alloc (sizeof (*fsh));
+  memset (fsh, 0, sizeof (*fsh));
+  sh->opaque[0] = fsh;
+  s->h = fsh;
+  fsh->segment_name = format (0, "%s%c", a->segment_name, 0);
+
+  /* Avoid vec_add1(...) failure when adding a fifo, etc. */
+  vec_validate (fsh->fifos, 64);
+  _vec_len (fsh->fifos) = 0;
+
+  ssvm_pop_heap (oldheap);
+
+  sh->ready = 1;
+  a->new_segment_index = s - sm->segments;
+  return (0);
+}
+
+/** (slave) attach to an svm fifo segment */
+int
+svm_fifo_segment_attach (svm_fifo_segment_create_args_t * a)
+{
+  int rv;
+  svm_fifo_segment_private_t *s;
+  svm_fifo_segment_main_t *sm = &svm_fifo_segment_main;
+  ssvm_shared_header_t *sh;
+  svm_fifo_segment_header_t *fsh;
+
+  /* Allocate a fresh segment */
+  pool_get (sm->segments, s);
+
+  memset (s, 0, sizeof (*s));
+
+  s->ssvm.ssvm_size = a->segment_size;
+  s->ssvm.my_pid = getpid ();
+  s->ssvm.name = (u8 *) a->segment_name;
+  s->ssvm.requested_va = sm->next_baseva;
+
+  rv = ssvm_slave_init (&s->ssvm, sm->timeout_in_seconds);
+
+  if (rv)
+    {
+      _vec_len (s) = vec_len (s) - 1;
+      return (rv);
+    }
+
+  /* Fish the segment header */
+  sh = s->ssvm.sh;
+  fsh = (svm_fifo_segment_header_t *) sh->opaque[0];
+  s->h = fsh;
+
+  a->new_segment_index = s - sm->segments;
+  return (0);
+}
+
+void
+svm_fifo_segment_delete (svm_fifo_segment_private_t * s)
+{
+  svm_fifo_segment_main_t *sm = &svm_fifo_segment_main;
+  ssvm_delete (&s->ssvm);
+  pool_put (sm->segments, s);
+}
+
+svm_fifo_t *
+svm_fifo_segment_alloc_fifo (svm_fifo_segment_private_t * s,
+			     u32 data_size_in_bytes)
+{
+  ssvm_shared_header_t *sh;
+  svm_fifo_segment_header_t *fsh;
+  svm_fifo_t *f;
+  void *oldheap;
+
+  sh = s->ssvm.sh;
+  fsh = (svm_fifo_segment_header_t *) sh->opaque[0];
+  oldheap = ssvm_push_heap (sh);
+
+  /* Note: this can fail, in which case: create another segment */
+  f = svm_fifo_create (data_size_in_bytes);
+  if (f == 0)
+    {
+      ssvm_pop_heap (oldheap);
+      return (0);
+    }
+
+  vec_add1 (fsh->fifos, f);
+
+  ssvm_pop_heap (oldheap);
+  return (f);
+}
+
+void
+svm_fifo_segment_free_fifo (svm_fifo_segment_private_t * s, svm_fifo_t * f)
+{
+  ssvm_shared_header_t *sh;
+  svm_fifo_segment_header_t *fsh;
+  void *oldheap;
+  int i;
+
+  sh = s->ssvm.sh;
+  fsh = (svm_fifo_segment_header_t *) sh->opaque[0];
+  oldheap = ssvm_push_heap (sh);
+
+  for (i = 0; i < vec_len (fsh->fifos); i++)
+    {
+      if (fsh->fifos[i] == f)
+	{
+	  vec_delete (fsh->fifos, 1, i);
+	  goto found;
+	}
+    }
+  clib_warning ("fifo 0x%llx not found in fifo table...", f);
+
+found:
+  clib_mem_free (f);
+  ssvm_pop_heap (oldheap);
+}
+
+void
+svm_fifo_segment_init (u64 baseva, u32 timeout_in_seconds)
+{
+  svm_fifo_segment_main_t *sm = &svm_fifo_segment_main;
+
+  sm->next_baseva = baseva;
+  sm->timeout_in_seconds = timeout_in_seconds;
+}
+
+u32
+svm_fifo_segment_index (svm_fifo_segment_private_t * s)
+{
+  return s - svm_fifo_segment_main.segments;
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/svm/svm_fifo_segment.h b/src/svm/svm_fifo_segment.h
new file mode 100644
index 00000000..793fa7c8
--- /dev/null
+++ b/src/svm/svm_fifo_segment.h
@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef __included_ssvm_fifo_segment_h__
+#define __included_ssvm_fifo_segment_h__
+
+#include "svm_fifo.h"
+#include "ssvm.h"
+
+typedef struct
+{
+  volatile svm_fifo_t **fifos;
+  u8 *segment_name;
+} svm_fifo_segment_header_t;
+
+typedef struct
+{
+  ssvm_private_t ssvm;
+  svm_fifo_segment_header_t *h;
+} svm_fifo_segment_private_t;
+
+typedef struct
+{
+  /** pool of segments */
+  svm_fifo_segment_private_t *segments;
+  /* Where to put the next one */
+  u64 next_baseva;
+  u32 timeout_in_seconds;
+} svm_fifo_segment_main_t;
+
+extern svm_fifo_segment_main_t svm_fifo_segment_main;
+
+typedef struct
+{
+  char *segment_name;
+  u32 segment_size;
+  u32 new_segment_index;
+} svm_fifo_segment_create_args_t;
+
+static inline svm_fifo_segment_private_t *
+svm_fifo_get_segment (u32 segment_index)
+{
+  svm_fifo_segment_main_t *ssm = &svm_fifo_segment_main;
+  return vec_elt_at_index (ssm->segments, segment_index);
+}
+
+#define foreach_ssvm_fifo_segment_api_error             \
+_(OUT_OF_SPACE, "Out of space in segment", -200)
+
+typedef enum
+{
+#define _(n,s,c) SSVM_FIFO_SEGMENT_API_ERROR_##n = c,
+  foreach_ssvm_fifo_segment_api_error
+#undef _
+} ssvm_fifo_segment_api_error_enum_t;
+
+int svm_fifo_segment_create (svm_fifo_segment_create_args_t * a);
+int svm_fifo_segment_attach (svm_fifo_segment_create_args_t * a);
+void svm_fifo_segment_delete (svm_fifo_segment_private_t * s);
+
+svm_fifo_t *svm_fifo_segment_alloc_fifo (svm_fifo_segment_private_t * s,
+					 u32 data_size_in_bytes);
+void svm_fifo_segment_free_fifo (svm_fifo_segment_private_t * s,
+				 svm_fifo_t * f);
+
+void svm_fifo_segment_init (u64 baseva, u32 timeout_in_seconds);
+
+u32 svm_fifo_segment_index (svm_fifo_segment_private_t * s);
+
+#endif /* __included_ssvm_fifo_segment_h__ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/svm/test_svm_fifo1.c b/src/svm/test_svm_fifo1.c
new file mode 100644
index 00000000..355653df
--- /dev/null
+++ b/src/svm/test_svm_fifo1.c
@@ -0,0 +1,361 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "svm_fifo_segment.h"
+
+clib_error_t *
+hello_world (int verbose)
+{
+  svm_fifo_segment_create_args_t _a, *a = &_a;
+  svm_fifo_segment_private_t *sp;
+  svm_fifo_t *f;
+  int rv;
+  u8 *test_data;
+  u8 *retrieved_data = 0;
+  clib_error_t *error = 0;
+  int pid = getpid ();
+
+  memset (a, 0, sizeof (*a));
+
+  a->segment_name = "fifo-test1";
+  a->segment_size = 256 << 10;
+
+  rv = svm_fifo_segment_create (a);
+
+  if (rv)
+    return clib_error_return (0, "svm_fifo_segment_create returned %d", rv);
+
+  sp = svm_fifo_get_segment (a->new_segment_index);
+
+  f = svm_fifo_segment_alloc_fifo (sp, 4096);
+
+  if (f == 0)
+    return clib_error_return (0, "svm_fifo_segment_alloc_fifo failed");
+
+  test_data = format (0, "Hello world%c", 0);
+  vec_validate (retrieved_data, vec_len (test_data) - 1);
+
+  while (svm_fifo_max_enqueue (f) >= vec_len (test_data))
+    svm_fifo_enqueue_nowait (f, pid, vec_len (test_data), test_data);
+
+  while (svm_fifo_max_dequeue (f) >= vec_len (test_data))
+    svm_fifo_dequeue_nowait (f, pid, vec_len (retrieved_data),
+			     retrieved_data);
+
+  while (svm_fifo_max_enqueue (f) >= vec_len (test_data))
+    svm_fifo_enqueue_nowait (f, pid, vec_len (test_data), test_data);
+
+  while (svm_fifo_max_dequeue (f) >= vec_len (test_data))
+    svm_fifo_dequeue_nowait (f, pid, vec_len (retrieved_data),
+			     retrieved_data);
+
+  if (!memcmp (retrieved_data, test_data, vec_len (test_data)))
+    error = clib_error_return (0, "data test OK, got '%s'", retrieved_data);
+  else
+    error = clib_error_return (0, "data test FAIL!");
+
+  svm_fifo_segment_free_fifo (sp, f);
+
+  return error;
+}
+
+clib_error_t *
+master (int verbose)
+{
+  svm_fifo_segment_create_args_t _a, *a = &_a;
+  svm_fifo_segment_private_t *sp;
+  svm_fifo_t *f;
+  int rv;
+  u8 *test_data;
+  u8 *retrieved_data = 0;
+  int i;
+  int pid = getpid ();
+
+  memset (a, 0, sizeof (*a));
+
+  a->segment_name = "fifo-test1";
+  a->segment_size = 256 << 10;
+
+  rv = svm_fifo_segment_create (a);
+
+  if (rv)
+    return clib_error_return (0, "svm_fifo_segment_create returned %d", rv);
+
+  sp = svm_fifo_get_segment (a->new_segment_index);
+
+  f = svm_fifo_segment_alloc_fifo (sp, 4096);
+
+  if (f == 0)
+    return clib_error_return (0, "svm_fifo_segment_alloc_fifo failed");
+
+  test_data = format (0, "Hello world%c", 0);
+  vec_validate (retrieved_data, vec_len (test_data) - 1);
+
+  for (i = 0; i < 1000; i++)
+    svm_fifo_enqueue_nowait (f, pid, vec_len (test_data), test_data);
+
+  return clib_error_return (0, "master (enqueue) done");
+}
+
+clib_error_t *
+mempig (int verbose)
+{
+  svm_fifo_segment_create_args_t _a, *a = &_a;
+  svm_fifo_segment_private_t *sp;
+  svm_fifo_t *f;
+  svm_fifo_t **flist = 0;
+  int rv;
+  int i;
+
+  memset (a, 0, sizeof (*a));
+
+  a->segment_name = "fifo-test1";
+  a->segment_size = 256 << 10;
+
+  rv = svm_fifo_segment_create (a);
+
+  if (rv)
+    return clib_error_return (0, "svm_fifo_segment_create returned %d", rv);
+
+  sp = svm_fifo_get_segment (a->new_segment_index);
+
+  for (i = 0; i < 1000; i++)
+    {
+      f = svm_fifo_segment_alloc_fifo (sp, 4096);
+      if (f == 0)
+	break;
+      vec_add1 (flist, f);
+    }
+
+  fformat (stdout, "Try #1: created %d fifos...\n", vec_len (flist));
+  for (i = 0; i < vec_len (flist); i++)
+    {
+      f = flist[i];
+      svm_fifo_segment_free_fifo (sp, f);
+    }
+
+  _vec_len (flist) = 0;
+
+  for (i = 0; i < 1000; i++)
+    {
+      f = svm_fifo_segment_alloc_fifo (sp, 4096);
+      if (f == 0)
+	break;
+      vec_add1 (flist, f);
+    }
+
+  fformat (stdout, "Try #2: created %d fifos...\n", vec_len (flist));
+  for (i = 0; i < vec_len (flist); i++)
+    {
+      f = flist[i];
+      svm_fifo_segment_free_fifo (sp, f);
+    }
+
+  return 0;
+}
+
+clib_error_t *
+offset (int verbose)
+{
+  svm_fifo_segment_create_args_t _a, *a = &_a;
+  svm_fifo_segment_private_t *sp;
+  svm_fifo_t *f;
+  int rv;
+  u32 *test_data = 0;
+  u32 *recovered_data = 0;
+  int i;
+  int pid = getpid ();
+
+  memset (a, 0, sizeof (*a));
+
+  a->segment_name = "fifo-test1";
+  a->segment_size = 256 << 10;
+
+  rv = svm_fifo_segment_create (a);
+
+  if (rv)
+    return clib_error_return (0, "svm_fifo_segment_create returned %d", rv);
+
+  sp = svm_fifo_get_segment (a->new_segment_index);
+
+  f = svm_fifo_segment_alloc_fifo (sp, 200 << 10);
+
+  if (f == 0)
+    return clib_error_return (0, "svm_fifo_segment_alloc_fifo failed");
+
+  for (i = 0; i < (3 * 1024); i++)
+    vec_add1 (test_data, i);
+
+  /* Enqueue the first 1024 u32's */
+  svm_fifo_enqueue_nowait (f, pid, 4096 /* bytes to enqueue */ ,
+			   (u8 *) test_data);
+
+  /* Enqueue the third 1024 u32's 2048 ahead of the current tail */
+  svm_fifo_enqueue_with_offset (f, pid, 4096, 4096, (u8 *) & test_data[2048]);
+
+  /* Enqueue the second 1024 u32's at the current tail */
+  svm_fifo_enqueue_nowait (f, pid, 4096 /* bytes to enqueue */ ,
+			   (u8 *) & test_data[1024]);
+
+  vec_validate (recovered_data, (3 * 1024) - 1);
+
+  svm_fifo_dequeue_nowait (f, pid, 3 * 4096, (u8 *) recovered_data);
+
+  for (i = 0; i < (3 * 1024); i++)
+    {
+      if (recovered_data[i] != test_data[i])
+	{
+	  clib_warning ("[%d] expected %d recovered %d", i,
+			test_data[i], recovered_data[i]);
+	  return clib_error_return (0, "offset test FAILED");
+	}
+    }
+
+  return clib_error_return (0, "offset test OK");
+}
+
+clib_error_t *
+slave (int verbose)
+{
+  svm_fifo_segment_create_args_t _a, *a = &_a;
+  svm_fifo_segment_private_t *sp;
+  svm_fifo_segment_header_t *fsh;
+  svm_fifo_t *f;
+  ssvm_shared_header_t *sh;
+  int rv;
+  u8 *test_data;
+  u8 *retrieved_data = 0;
+  int pid = getpid ();
+  int i;
+
+  memset (a, 0, sizeof (*a));
+
+  a->segment_name = "fifo-test1";
+
+  rv = svm_fifo_segment_attach (a);
+
+  if (rv)
+    return clib_error_return (0, "svm_fifo_segment_attach returned %d", rv);
+
+  sp = svm_fifo_get_segment (a->new_segment_index);
+  sh = sp->ssvm.sh;
+  fsh = (svm_fifo_segment_header_t *) sh->opaque[0];
+
+  /* might wanna wait.. */
+  f = (svm_fifo_t *) fsh->fifos[0];
+
+  /* Lazy bastards united */
+  test_data = format (0, "Hello world%c", 0);
+  vec_validate (retrieved_data, vec_len (test_data) - 1);
+
+  for (i = 0; i < 1000; i++)
+    {
+      svm_fifo_dequeue_nowait (f, pid, vec_len (retrieved_data),
+			       retrieved_data);
+      if (memcmp (retrieved_data, test_data, vec_len (retrieved_data)))
+	return clib_error_return (0, "retrieved data incorrect, '%s'",
+				  retrieved_data);
+    }
+
+  return clib_error_return (0, "slave (dequeue) done");
+}
+
+
+int
+test_ssvm_fifo1 (unformat_input_t * input)
+{
+  clib_error_t *error = 0;
+  int verbose = 0;
+  int test_id = 0;
+
+  svm_fifo_segment_init (0x200000000ULL, 20);
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "verbose %d", &verbose))
+	;
+      else if (unformat (input, "verbose"))
+	verbose = 1;
+      else if (unformat (input, "master"))
+	test_id = 1;
+      else if (unformat (input, "slave"))
+	test_id = 2;
+      else if (unformat (input, "mempig"))
+	test_id = 3;
+      else if (unformat (input, "offset"))
+	test_id = 4;
+      else
+	{
+	  error = clib_error_create ("unknown input `%U'\n",
+				     format_unformat_error, input);
+	  goto out;
+	}
+    }
+
+  switch (test_id)
+    {
+    case 0:
+      error = hello_world (verbose);
+      break;
+
+    case 1:
+      error = master (verbose);
+      break;
+
+    case 2:
+      error = slave (verbose);
+      break;
+
+    case 3:
+      error = mempig (verbose);
+      break;
+
+    case 4:
+      error = offset (verbose);
+      break;
+
+    default:
+      error = clib_error_return (0, "test id %d unknown", test_id);
+      break;
+    }
+
+out:
+  if (error)
+    clib_error_report (error);
+
+  return 0;
+}
+
+
+
+int
+main (int argc, char *argv[])
+{
+  unformat_input_t i;
+  int r;
+
+  unformat_init_command_line (&i, argv);
+  r = test_ssvm_fifo1 (&i);
+  unformat_free (&i);
+  return r;
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */