session: cleanup segment manager and fifo segment

Change-Id: I984f347fb465c0c405cef668d8690457e81788e2
Signed-off-by: Florin Coras <fcoras@cisco.com>
diff --git a/src/svm/CMakeLists.txt b/src/svm/CMakeLists.txt
index ab6f7f7..7664014 100644
--- a/src/svm/CMakeLists.txt
+++ b/src/svm/CMakeLists.txt
@@ -16,23 +16,23 @@
 ##############################################################################
 add_vpp_library(svm
   SOURCES
+  fifo_segment.c
+  message_queue.c
+  queue.c
   svm.c
   ssvm.c
   svm_fifo.c
-  svm_fifo_segment.c
-  queue.c
-  message_queue.c
 
   MULTIARCH_SOURCES
   svm_fifo.c
 
   INSTALL_HEADERS
+  fifo_segment.h
+  message_queue.h
+  queue.h
   ssvm.h
   svm_common.h
   svm_fifo.h
-  svm_fifo_segment.h
-  queue.h
-  message_queue.h
   svm.h
   svmdb.h
 
diff --git a/src/svm/fifo_segment.c b/src/svm/fifo_segment.c
new file mode 100644
index 0000000..6bf2634
--- /dev/null
+++ b/src/svm/fifo_segment.c
@@ -0,0 +1,639 @@
+/*
+ * Copyright (c) 2016-2019 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>
+
+/**
+ * Initialize fifo segment shared header
+ */
+int
+fifo_segment_init (fifo_segment_t * fs)
+{
+  fifo_segment_header_t *fsh;
+  ssvm_shared_header_t *sh;
+  void *oldheap;
+
+  sh = fs->ssvm.sh;
+  oldheap = ssvm_push_heap (sh);
+
+  fsh = clib_mem_alloc (sizeof (*fsh));
+  clib_memset (fsh, 0, sizeof (*fsh));
+  fs->h = sh->opaque[0] = fsh;
+
+  ssvm_pop_heap (oldheap);
+
+  sh->ready = 1;
+  return (0);
+}
+
+/**
+ * Create a fifo segment in process-private memory
+ */
+static int
+fifo_segment_create_process_private (fifo_segment_main_t * sm,
+				     fifo_segment_create_args_t * a)
+{
+  u32 pagesize = clib_mem_get_page_size ();
+  ssvm_shared_header_t *sh;
+  fifo_segment_t *s;
+  u32 rnd_size = 0;
+  u8 *heap;
+
+  pool_get (sm->segments, s);
+  clib_memset (s, 0, sizeof (*s));
+
+  rnd_size = (a->segment_size + (pagesize - 1)) & ~pagesize;
+
+#if USE_DLMALLOC == 0
+  heap = mheap_alloc (0, rnd_size);
+  if (heap == 0)
+    {
+      clib_unix_warning ("mheap alloc");
+      pool_put (sm->segments, s);
+      return -1;
+    }
+  {
+    mheap_t *heap_header;
+    heap_header = mheap_header (heap);
+    heap_header->flags |= MHEAP_FLAG_THREAD_SAFE;
+  }
+#else
+  heap = create_mspace (rnd_size, 1 /* locked */ );
+#endif
+
+  s->ssvm.ssvm_size = rnd_size;
+  s->ssvm.i_am_master = 1;
+  s->ssvm.my_pid = getpid ();
+  s->ssvm.name = format (0, "%s%c", a->segment_name, 0);
+  s->ssvm.requested_va = ~0;
+
+  /* Allocate a [sic] shared memory header, in process memory... */
+  sh = clib_mem_alloc_aligned (sizeof (*sh), CLIB_CACHE_LINE_BYTES);
+  s->ssvm.sh = sh;
+
+  clib_memset (sh, 0, sizeof (*sh));
+  sh->heap = heap;
+
+  fifo_segment_init (s);
+  vec_add1 (a->new_segment_indices, s - sm->segments);
+
+  return (0);
+}
+
+/**
+ * Create a fifo segment and initialize as master
+ */
+int
+fifo_segment_create (fifo_segment_main_t * sm, fifo_segment_create_args_t * a)
+{
+  fifo_segment_t *s;
+  int rv;
+
+  if (a->segment_type == SSVM_SEGMENT_PRIVATE)
+    return fifo_segment_create_process_private (sm, a);
+
+  /* Allocate a fresh segment */
+  pool_get (sm->segments, s);
+  clib_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 = format (0, "%s%c", a->segment_name, 0);
+  s->ssvm.requested_va = sm->next_baseva;
+
+  if ((rv = ssvm_master_init (&s->ssvm, a->segment_type)))
+    {
+      pool_put (sm->segments, s);
+      return (rv);
+    }
+
+  /* Note: requested_va updated due to seg base addr randomization */
+  sm->next_baseva = s->ssvm.sh->ssvm_va + a->segment_size;
+
+  fifo_segment_init (s);
+  vec_add1 (a->new_segment_indices, s - sm->segments);
+  return (0);
+}
+
+/**
+ * Attach as slave to a fifo segment
+ */
+int
+fifo_segment_attach (fifo_segment_main_t * sm, fifo_segment_create_args_t * a)
+{
+  fifo_segment_t *s;
+  int rv;
+
+  pool_get_zero (sm->segments, s);
+
+  s->ssvm.ssvm_size = a->segment_size;
+  s->ssvm.my_pid = getpid ();
+  s->ssvm.name = format (0, "%s%c", a->segment_name, 0);
+  s->ssvm.requested_va = sm->next_baseva;
+  if (a->segment_type == SSVM_SEGMENT_MEMFD)
+    s->ssvm.fd = a->memfd_fd;
+  else
+    s->ssvm.attach_timeout = sm->timeout_in_seconds;
+
+  if ((rv = ssvm_slave_init (&s->ssvm, a->segment_type)))
+    {
+      _vec_len (s) = vec_len (s) - 1;
+      return (rv);
+    }
+
+  /* Fish the segment header */
+  s->h = s->ssvm.sh->opaque[0];
+
+  vec_add1 (a->new_segment_indices, s - sm->segments);
+  return (0);
+}
+
+void
+fifo_segment_delete (fifo_segment_main_t * sm, fifo_segment_t * s)
+{
+  ssvm_delete (&s->ssvm);
+  clib_memset (s, 0xfe, sizeof (*s));
+  pool_put (sm->segments, s);
+}
+
+u32
+fifo_segment_index (fifo_segment_main_t * sm, fifo_segment_t * s)
+{
+  return s - sm->segments;
+}
+
+void *
+svm_fifo_segment_heap (fifo_segment_t * seg)
+{
+  return seg->ssvm.sh->heap;
+}
+
+fifo_segment_t *
+fifo_segment_get_segment (fifo_segment_main_t * sm, u32 segment_index)
+{
+  return pool_elt_at_index (sm->segments, segment_index);
+}
+
+void
+fifo_segment_info (fifo_segment_t * seg, char **address, size_t * size)
+{
+  if (ssvm_type (&seg->ssvm) == SSVM_SEGMENT_PRIVATE)
+    {
+#if USE_DLMALLOC == 0
+      mheap_t *heap_header;
+
+      *address = pointer_to_uword (seg->ssvm.sh->heap);
+      heap_header = mheap_header (seg->ssvm.sh->heap);
+      *size = heap_header->max_size;
+#else
+      mspace_get_address_and_size (seg->ssvm.sh->heap, address, size);
+#endif
+    }
+  else
+    {
+      *address = (char *) seg->ssvm.sh->ssvm_va;
+      *size = seg->ssvm.ssvm_size;
+    }
+}
+
+void
+fifo_segment_main_init (fifo_segment_main_t * sm, u64 baseva,
+			u32 timeout_in_seconds)
+{
+  sm->next_baseva = baseva;
+  sm->timeout_in_seconds = timeout_in_seconds;
+}
+
+static void
+fifo_init_for_segment (fifo_segment_header_t * fsh, svm_fifo_t * f,
+		       u32 size, u32 fl_index)
+{
+  f->freelist_index = fl_index;
+  f->default_chunk.start_byte = 0;
+  f->default_chunk.length = size;
+  f->default_chunk.next = f->start_chunk = f->end_chunk = &f->default_chunk;
+  f->head_chunk = f->tail_chunk = f->ooo_enq = f->ooo_deq = f->start_chunk;
+  f->next = fsh->free_fifos[fl_index];
+  fsh->free_fifos[fl_index] = f;
+}
+
+static inline int
+fs_free_list_for_size (u32 size)
+{
+  return max_log2 (size) - max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE);
+}
+
+static inline int
+fs_fifo_size_is_valid (u32 size)
+{
+  /*
+   * 4K minimum. It's not likely that anything good will happen
+   * with a smaller FIFO.
+   */
+  return size >= FIFO_SEGMENT_MIN_FIFO_SIZE
+    && size <= FIFO_SEGMENT_MAX_FIFO_SIZE;
+}
+
+static void
+allocate_new_fifo_batch (fifo_segment_header_t * fsh,
+			 u32 data_size_in_bytes, int chunk_size)
+{
+  u32 size, rounded_data_size;
+  int i, fl_index;
+  u8 *fifos_mem;
+  svm_fifo_t *f;
+
+  rounded_data_size = (1 << (max_log2 (data_size_in_bytes)));
+  fl_index = fs_free_list_for_size (data_size_in_bytes);
+
+  /* Calculate space requirement $$$ round-up data_size_in_bytes */
+  size = (sizeof (*f) + rounded_data_size) * chunk_size;
+
+  /* Allocate fifo space. May fail. */
+  fifos_mem = clib_mem_alloc_aligned_at_offset (size, CLIB_CACHE_LINE_BYTES,
+						0 /* align_offset */ ,
+						0 /* os_out_of_memory */ );
+
+  /* Out of space.. */
+  if (fifos_mem == 0)
+    return;
+
+  /* Carve fifo space */
+  for (i = 0; i < chunk_size; i++)
+    {
+      f = (svm_fifo_t *) fifos_mem;
+      fifo_init_for_segment (fsh, f, rounded_data_size, fl_index);
+      fifos_mem += sizeof (*f) + rounded_data_size;
+    }
+}
+
+/**
+ * Allocate fifo in fifo segment
+ */
+svm_fifo_t *
+fifo_segment_alloc_fifo (fifo_segment_t * fs, u32 data_bytes,
+			 fifo_segment_ftype_t ftype)
+{
+  fifo_segment_header_t *fsh;
+  ssvm_shared_header_t *sh;
+  svm_fifo_t *f = 0;
+  void *oldheap;
+  int fl_index;
+
+  if (!fs_fifo_size_is_valid (data_bytes))
+    {
+      clib_warning ("fifo size out of range %d", data_bytes);
+      return 0;
+    }
+
+  fl_index = fs_free_list_for_size (data_bytes);
+
+  sh = fs->ssvm.sh;
+  ssvm_lock_non_recursive (sh, 1);
+
+  fsh = (fifo_segment_header_t *) sh->opaque[0];
+  vec_validate_init_empty (fsh->free_fifos, fl_index, 0);
+  f = fsh->free_fifos[fl_index];
+
+  /* Try to allocate batch of fifos */
+  if (PREDICT_FALSE (!f))
+    {
+      oldheap = ssvm_push_heap (sh);
+      allocate_new_fifo_batch (fsh, data_bytes,
+			       FIFO_SEGMENT_ALLOC_BATCH_SIZE);
+      ssvm_pop_heap (oldheap);
+      f = fsh->free_fifos[fl_index];
+    }
+  if (PREDICT_TRUE (f != 0))
+    {
+      fsh->free_fifos[fl_index] = f->next;
+      /* (re)initialize the fifo, as in svm_fifo_create */
+      memset (f, 0, sizeof (*f));
+      svm_fifo_init (f, data_bytes);
+      goto found;
+    }
+
+  /* Failed to allocate batch, try just one fifo. This can also fail,
+   * in which case, create another segment */
+  oldheap = ssvm_push_heap (sh);
+  f = svm_fifo_create (data_bytes);
+  ssvm_pop_heap (oldheap);
+
+  if (PREDICT_FALSE (f == 0))
+    goto done;
+
+  f->freelist_index = fl_index;
+
+found:
+  /* If rx fifo type add to active fifos list. When cleaning up segment,
+   * we need a list of active sessions that should be disconnected. Since
+   * both rx and tx fifos keep pointers to the session, it's enough to track
+   * only one. */
+  if (ftype == FIFO_SEGMENT_RX_FIFO)
+    {
+      if (fsh->fifos)
+	{
+	  fsh->fifos->prev = f;
+	  f->next = fsh->fifos;
+	}
+      fsh->fifos = f;
+      f->flags |= SVM_FIFO_F_LL_TRACKED;
+    }
+  fsh->n_active_fifos++;
+
+done:
+  ssvm_unlock_non_recursive (sh);
+  return (f);
+}
+
+/**
+ * Free fifo allocated in fifo segment
+ */
+void
+fifo_segment_free_fifo (fifo_segment_t * s, svm_fifo_t * f)
+{
+  fifo_segment_header_t *fsh;
+  ssvm_shared_header_t *sh;
+  int fl_index;
+
+  ASSERT (f->refcnt > 0);
+
+  if (--f->refcnt > 0)
+    return;
+
+  sh = s->ssvm.sh;
+  fsh = (fifo_segment_header_t *) sh->opaque[0];
+  fl_index = f->freelist_index;
+
+  ASSERT (fl_index < vec_len (fsh->free_fifos));
+
+  ssvm_lock_non_recursive (sh, 2);
+
+  /* Remove from active list. Only rx fifos are tracked */
+  if (f->flags & SVM_FIFO_F_LL_TRACKED)
+    {
+      if (f->prev)
+	f->prev->next = f->next;
+      else
+	fsh->fifos = f->next;
+      if (f->next)
+	f->next->prev = f->prev;
+      f->flags &= ~SVM_FIFO_F_LL_TRACKED;
+    }
+
+  /* Add to free list */
+  f->next = fsh->free_fifos[fl_index];
+  f->prev = 0;
+  fsh->free_fifos[fl_index] = f;
+
+  if (CLIB_DEBUG)
+    {
+      f->master_session_index = ~0;
+      f->master_thread_index = ~0;
+    }
+
+  fsh->n_active_fifos--;
+  ssvm_unlock_non_recursive (sh);
+}
+
+/**
+ * Pre-allocates fifo pairs in fifo segment
+ */
+void
+fifo_segment_preallocate_fifo_pairs (fifo_segment_t * fs,
+				     u32 rx_fifo_size, u32 tx_fifo_size,
+				     u32 * n_fifo_pairs)
+{
+  u32 rx_rounded_data_size, tx_rounded_data_size, pair_size;
+  u32 rx_fifos_size, tx_fifos_size, pairs_to_allocate;
+  ssvm_shared_header_t *sh = fs->ssvm.sh;
+  fifo_segment_header_t *fsh = fs->h;
+  int i, rx_fl_index, tx_fl_index;
+  u8 *rx_fifo_mem, *tx_fifo_mem;
+  uword space_available;
+  void *oldheap;
+  svm_fifo_t *f;
+
+  /* Parameter check */
+  if (rx_fifo_size == 0 || tx_fifo_size == 0 || *n_fifo_pairs == 0)
+    return;
+
+  if (!fs_fifo_size_is_valid (rx_fifo_size))
+    {
+      clib_warning ("rx fifo_size out of range %d", rx_fifo_size);
+      return;
+    }
+
+  if (!fs_fifo_size_is_valid (tx_fifo_size))
+    {
+      clib_warning ("tx fifo_size out of range %d", tx_fifo_size);
+      return;
+    }
+
+  rx_rounded_data_size = (1 << (max_log2 (rx_fifo_size)));
+  rx_fl_index = fs_free_list_for_size (rx_fifo_size);
+  tx_rounded_data_size = (1 << (max_log2 (tx_fifo_size)));
+  tx_fl_index = fs_free_list_for_size (tx_fifo_size);
+
+  /* Calculate space requirements */
+  pair_size = 2 * sizeof (*f) + rx_rounded_data_size + tx_rounded_data_size;
+#if USE_DLMALLOC == 0
+  space_available = fs->ssvm.ssvm_size - mheap_bytes (sh->heap);
+#else
+  space_available = fs->ssvm.ssvm_size - mspace_usable_size (sh->heap);
+#endif
+
+  pairs_to_allocate = clib_min (space_available / pair_size, *n_fifo_pairs);
+  rx_fifos_size = (sizeof (*f) + rx_rounded_data_size) * pairs_to_allocate;
+  tx_fifos_size = (sizeof (*f) + tx_rounded_data_size) * pairs_to_allocate;
+
+  vec_validate_init_empty (fsh->free_fifos,
+			   clib_max (rx_fl_index, tx_fl_index), 0);
+
+  oldheap = ssvm_push_heap (sh);
+
+  /* Allocate rx and tx fifo memory. May fail. */
+  rx_fifo_mem = clib_mem_alloc_aligned_at_offset (rx_fifos_size,
+						  CLIB_CACHE_LINE_BYTES,
+						  0 /* align_offset */ ,
+						  0 /* os_out_of_memory */ );
+  tx_fifo_mem = clib_mem_alloc_aligned_at_offset (tx_fifos_size,
+						  CLIB_CACHE_LINE_BYTES,
+						  0 /* align_offset */ ,
+						  0 /* os_out_of_memory */ );
+
+  /* Make sure it worked. Clean up if it didn't... */
+  if (rx_fifo_mem == 0 || tx_fifo_mem == 0)
+    {
+      rx_fifo_mem ? clib_mem_free (rx_fifo_mem) : clib_mem_free (tx_fifo_mem);
+      clib_warning ("fifo preallocation failure: rx size %d tx size %u "
+		    "npairs %d", rx_fifo_size, tx_fifo_size, *n_fifo_pairs);
+      ssvm_pop_heap (oldheap);
+      return;
+    }
+
+  /* Carve rx and tx fifo memory */
+  for (i = 0; i < pairs_to_allocate; i++)
+    {
+      f = (svm_fifo_t *) rx_fifo_mem;
+      fifo_init_for_segment (fsh, f, rx_rounded_data_size, rx_fl_index);
+      rx_fifo_mem += sizeof (*f) + rx_rounded_data_size;
+
+      f = (svm_fifo_t *) tx_fifo_mem;
+      fifo_init_for_segment (fsh, f, tx_rounded_data_size, tx_fl_index);
+      tx_fifo_mem += sizeof (*f) + tx_rounded_data_size;
+    }
+
+  /* Account for the pairs allocated */
+  *n_fifo_pairs -= pairs_to_allocate;
+  ssvm_pop_heap (oldheap);
+}
+
+/**
+ * Get number of active fifos
+ */
+u32
+fifo_segment_num_fifos (fifo_segment_t * fs)
+{
+  return fs->h->n_active_fifos;
+}
+
+u32
+fifo_segment_num_free_fifos (fifo_segment_t * fs, u32 fifo_size_in_bytes)
+{
+  u32 count = 0, rounded_data_size, fl_index;
+  fifo_segment_header_t *fsh;
+  ssvm_shared_header_t *sh;
+  svm_fifo_t *f;
+  int i;
+
+  sh = fs->ssvm.sh;
+  fsh = (fifo_segment_header_t *) sh->opaque[0];
+
+  /* Count all free fifos? */
+  if (fifo_size_in_bytes == ~0)
+    {
+      for (i = 0; i < vec_len (fsh->free_fifos); i++)
+	{
+	  f = fsh->free_fifos[i];
+	  if (f == 0)
+	    continue;
+
+	  while (f)
+	    {
+	      f = f->next;
+	      count++;
+	    }
+	}
+      return count;
+    }
+
+  rounded_data_size = (1 << (max_log2 (fifo_size_in_bytes)));
+  fl_index = fs_free_list_for_size (rounded_data_size);
+
+  if (fl_index >= vec_len (fsh->free_fifos))
+    return 0;
+
+  f = fsh->free_fifos[fl_index];
+  if (f == 0)
+    return 0;
+
+  while (f)
+    {
+      f = f->next;
+      count++;
+    }
+  return count;
+}
+
+u8
+fifo_segment_has_fifos (fifo_segment_t * fs)
+{
+  return fs->h->fifos != 0;
+}
+
+svm_fifo_t *
+fifo_segment_get_fifo_list (fifo_segment_t * fs)
+{
+  return fs->h->fifos;
+}
+
+u8 *
+format_fifo_segment_type (u8 * s, va_list * args)
+{
+  fifo_segment_t *sp;
+  sp = va_arg (*args, fifo_segment_t *);
+  ssvm_segment_type_t st = ssvm_type (&sp->ssvm);
+
+  if (st == SSVM_SEGMENT_PRIVATE)
+    s = format (s, "%s", "private-heap");
+  else if (st == SSVM_SEGMENT_MEMFD)
+    s = format (s, "%s", "memfd");
+  else if (st == SSVM_SEGMENT_SHM)
+    s = format (s, "%s", "shm");
+  else
+    s = format (s, "%s", "unknown");
+  return s;
+}
+
+/**
+ * Segment format function
+ */
+u8 *
+format_fifo_segment (u8 * s, va_list * args)
+{
+  fifo_segment_t *sp = va_arg (*args, fifo_segment_t *);
+  int verbose __attribute__ ((unused)) = va_arg (*args, int);
+  fifo_segment_header_t *fsh = sp->h;
+  u32 count, indent;
+  svm_fifo_t *f;
+  int i;
+
+  indent = format_get_indent (s) + 2;
+#if USE_DLMALLOC == 0
+  s = format (s, "%U segment heap: %U\n", format_white_space, indent,
+	      format_mheap, svm_fifo_segment_heap (sp), verbose);
+  s = format (s, "%U segment has %u active fifos\n",
+	      format_white_space, indent, fifo_segment_num_fifos (sp));
+#endif
+
+  for (i = 0; i < vec_len (fsh->free_fifos); i++)
+    {
+      f = fsh->free_fifos[i];
+      if (f == 0)
+	continue;
+      count = 0;
+      while (f)
+	{
+	  f = f->next;
+	  count++;
+	}
+
+      s = format (s, "%U%-5u Kb: %u free",
+		  format_white_space, indent + 2,
+		  1 << (i + max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE) - 10),
+		  count);
+    }
+  return s;
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/svm/fifo_segment.h b/src/svm/fifo_segment.h
new file mode 100644
index 0000000..cc0ff3a
--- /dev/null
+++ b/src/svm/fifo_segment.h
@@ -0,0 +1,139 @@
+/*
+ * Copyright (c) 2016-2019 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_fifo_segment_h__
+#define __included_fifo_segment_h__
+
+#include <svm/ssvm.h>
+#include <svm/svm_fifo.h>
+
+typedef enum
+{
+  FIFO_SEGMENT_FTYPE_NONE = -1,
+  FIFO_SEGMENT_RX_FIFO = 0,
+  FIFO_SEGMENT_TX_FIFO,
+  FIFO_SEGMENT_N_FTYPES
+} fifo_segment_ftype_t;
+
+#define FIFO_SEGMENT_MIN_FIFO_SIZE 4096	/* 4kB min fifo size */
+#define FIFO_SEGMENT_MAX_FIFO_SIZE (2 << 30)	/* 2GB max fifo size */
+#define FIFO_SEGMENT_ALLOC_BATCH_SIZE 32	/* Allocation quantum */
+
+typedef enum fifo_segment_flags_
+{
+  FIFO_SEGMENT_F_IS_PREALLOCATED = 1 << 0,
+  FIFO_SEGMENT_F_WILL_DELETE = 1 << 1,
+} fifo_segment_flags_t;
+
+typedef struct
+{
+  svm_fifo_t *fifos;		/**< Linked list of active RX fifos */
+  svm_fifo_t **free_fifos;	/**< Freelists, by fifo size  */
+  u32 n_active_fifos;		/**< Number of active fifos */
+  u8 flags;			/**< Segment flags */
+} fifo_segment_header_t;
+
+typedef struct
+{
+  ssvm_private_t ssvm;		/**< ssvm segment data */
+  fifo_segment_header_t *h;	/**< fifo segment data */
+} fifo_segment_t;
+
+typedef struct
+{
+  fifo_segment_t *segments;	/**< pool of fifo segments */
+  u64 next_baseva;		/**< Where to put the next one */
+  u32 timeout_in_seconds;	/**< Time to wait during attach */
+} fifo_segment_main_t;
+
+typedef struct
+{
+  ssvm_segment_type_t segment_type;	/**< type of segment requested */
+  u32 segment_size;			/**< size of the segment */
+  int memfd_fd;				/**< fd for memfd segments */
+  char *segment_name;			/**< segment name */
+  u32 *new_segment_indices;		/**< return vec of new seg indices */
+} fifo_segment_create_args_t;
+
+#define fifo_segment_flags(_fs) _fs->h->flags
+
+int fifo_segment_init (fifo_segment_t * fs);
+int fifo_segment_create (fifo_segment_main_t * sm,
+			 fifo_segment_create_args_t * a);
+int fifo_segment_attach (fifo_segment_main_t * sm,
+			 fifo_segment_create_args_t * a);
+void fifo_segment_delete (fifo_segment_main_t * sm, fifo_segment_t * fs);
+fifo_segment_t *fifo_segment_get_segment (fifo_segment_main_t * sm,
+					  u32 fs_index);
+u32 fifo_segment_index (fifo_segment_main_t * sm, fifo_segment_t * fs);
+void fifo_segment_info (fifo_segment_t * seg, char **address, size_t * size);
+
+/**
+ * Allocate fifo in fifo segment
+ *
+ * @param fs		fifo segment
+ * @param data_bytes	size of default fifo chunk in bytes
+ * @param ftype		fifo type @ref fifo_segment_ftype_t
+ * @return		new fifo or 0 if alloc failed
+ */
+svm_fifo_t *fifo_segment_alloc_fifo (fifo_segment_t * fs,
+				     u32 data_bytes,
+				     fifo_segment_ftype_t ftype);
+
+/**
+ * Free fifo allocated in fifo segment
+ *
+ * @param fs		fifo segment
+ * @param f		fifo to be freed
+ */
+void fifo_segment_free_fifo (fifo_segment_t * fs, svm_fifo_t * f);
+
+/**
+ * Pre-allocates fifo pairs in fifo segment
+ *
+ * The number of fifos pre-allocated is the minimum of the requested number
+ * of pairs and the maximum number that fit within the segment. If the maximum
+ * is hit, the number of fifo pairs requested is updated by subtracting the
+ * number of fifos that have been successfully allocated.
+ *
+ * @param fs		fifo segment
+ * @param rx_fifo_size	data size of rx fifos
+ * @param tx_fifo_size	data size of tx fifos
+ * @param n_fifo_pairs	number of pairs requested. Prior to returning, this
+ * 			is decremented by the the number of pairs allocated.
+ */
+void fifo_segment_preallocate_fifo_pairs (fifo_segment_t * fs,
+					  u32 rx_fifo_size,
+					  u32 tx_fifo_size,
+					  u32 * n_fifo_pairs);
+u8 fifo_segment_has_fifos (fifo_segment_t * fs);
+svm_fifo_t *fifo_segment_get_fifo_list (fifo_segment_t * fs);
+u32 fifo_segment_num_fifos (fifo_segment_t * fs);
+u32 fifo_segment_num_free_fifos (fifo_segment_t * fs, u32 fifo_size_in_bytes);
+
+void fifo_segment_main_init (fifo_segment_main_t * sm, u64 baseva,
+			     u32 timeout_in_seconds);
+
+format_function_t format_fifo_segment;
+format_function_t format_fifo_segment_type;
+
+#endif /* __included_fifo_segment_h__ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c
index a335519..eafe497 100644
--- a/src/svm/svm_fifo.c
+++ b/src/svm/svm_fifo.c
@@ -882,7 +882,7 @@
 }
 
 int
-svm_fifo_segments (svm_fifo_t * f, svm_fifo_segment_t * fs)
+svm_fifo_segments (svm_fifo_t * f, svm_fifo_seg_t * fs)
 {
   u32 cursize, head, tail, head_idx;
 
@@ -914,7 +914,7 @@
 }
 
 void
-svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_segment_t * fs)
+svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_seg_t * fs)
 {
   u32 head, head_idx;
 
diff --git a/src/svm/svm_fifo.h b/src/svm/svm_fifo.h
index 619d609..4f2f619 100644
--- a/src/svm/svm_fifo.h
+++ b/src/svm/svm_fifo.h
@@ -67,6 +67,7 @@
 {
   SVM_FIFO_F_SIZE_UPDATE = 1 << 0,
   SVM_FIFO_F_MULTI_CHUNK = 1 << 1,
+  SVM_FIFO_F_LL_TRACKED = 1 << 2,
 } svm_fifo_flag_t;
 
 typedef struct _svm_fifo
@@ -124,11 +125,11 @@
   SVM_FIFO_FULL = -2,
 } svm_fifo_err_t;
 
-typedef struct svm_fifo_segment_
+typedef struct svm_fifo_seg_
 {
   u8 *data;
   u32 len;
-} svm_fifo_segment_t;
+} svm_fifo_seg_t;
 
 #if SVM_FIFO_TRACE
 #define svm_fifo_trace_add(_f, _s, _l, _t)		\
@@ -352,8 +353,8 @@
 int svm_fifo_peek (svm_fifo_t * f, u32 offset, u32 max_bytes, u8 * copy_here);
 int svm_fifo_dequeue_drop (svm_fifo_t * f, u32 max_bytes);
 void svm_fifo_dequeue_drop_all (svm_fifo_t * f);
-int svm_fifo_segments (svm_fifo_t * f, svm_fifo_segment_t * fs);
-void svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_segment_t * fs);
+int svm_fifo_segments (svm_fifo_t * f, svm_fifo_seg_t * fs);
+void svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_seg_t * fs);
 void svm_fifo_init_pointers (svm_fifo_t * f, u32 head, u32 tail);
 void svm_fifo_clone (svm_fifo_t * df, svm_fifo_t * sf);
 void svm_fifo_overwrite_head (svm_fifo_t * f, u8 * data, u32 len);
diff --git a/src/svm/svm_fifo_segment.c b/src/svm/svm_fifo_segment.c
deleted file mode 100644
index 8a8bd4a..0000000
--- a/src/svm/svm_fifo_segment.c
+++ /dev/null
@@ -1,668 +0,0 @@
-/*
- * Copyright (c) 2016-2019 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>
-
-static void
-fifo_init_for_segment (svm_fifo_segment_header_t * fsh, u8 * fifo_space,
-		       u32 size, u32 freelist_index)
-{
-  svm_fifo_t *f;
-
-  f = (svm_fifo_t *) fifo_space;
-  f->freelist_index = freelist_index;
-  f->default_chunk.start_byte = 0;
-  f->default_chunk.length = size;
-  f->default_chunk.next = f->start_chunk = f->end_chunk = &f->default_chunk;
-  f->head_chunk = f->tail_chunk = f->ooo_enq = f->ooo_deq = f->start_chunk;
-  f->next = fsh->free_fifos[freelist_index];
-  fsh->free_fifos[freelist_index] = f;
-}
-
-static void
-allocate_new_fifo_chunk (svm_fifo_segment_header_t * fsh,
-			 u32 data_size_in_bytes, int chunk_size)
-{
-  int freelist_index;
-  u32 size;
-  u8 *fifo_space;
-  u32 rounded_data_size;
-  svm_fifo_t *f;
-  int i;
-
-  rounded_data_size = (1 << (max_log2 (data_size_in_bytes)));
-  freelist_index = max_log2 (rounded_data_size)
-    - max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE);
-
-  /* Calculate space requirement $$$ round-up data_size_in_bytes */
-  size = (sizeof (*f) + rounded_data_size) * chunk_size;
-
-  /* Allocate fifo space. May fail. */
-  fifo_space = clib_mem_alloc_aligned_at_offset
-    (size, CLIB_CACHE_LINE_BYTES, 0 /* align_offset */ ,
-     0 /* os_out_of_memory */ );
-
-  /* Out of space.. */
-  if (fifo_space == 0)
-    return;
-
-  /* Carve fifo space */
-  for (i = 0; i < chunk_size; i++)
-    {
-      fifo_init_for_segment (fsh, fifo_space, rounded_data_size,
-			     freelist_index);
-      fifo_space += sizeof (*f) + rounded_data_size;
-    }
-}
-
-/**
- * Pre-allocates fifo pairs in fifo segment
- *
- * The number of fifos pre-allocated is the minimum of the requested number
- * of pairs and the maximum number that fit within the segment. If the maximum
- * is hit, the number of fifo pairs requested is updated by subtracting the
- * number of fifos that have been successfully allocated.
- */
-void
-svm_fifo_segment_preallocate_fifo_pairs (svm_fifo_segment_private_t * s,
-					 u32 rx_fifo_size, u32 tx_fifo_size,
-					 u32 * n_fifo_pairs)
-{
-  u32 rx_rounded_data_size, tx_rounded_data_size, pair_size;
-  u32 rx_fifos_size, tx_fifos_size, pairs_to_allocate;
-  int rx_freelist_index, tx_freelist_index;
-  ssvm_shared_header_t *sh = s->ssvm.sh;
-  svm_fifo_segment_header_t *fsh = s->h;
-  u8 *rx_fifo_space, *tx_fifo_space;
-  uword space_available;
-  void *oldheap;
-  svm_fifo_t *f;
-  int i;
-
-  /* Parameter check */
-  if (rx_fifo_size == 0 || tx_fifo_size == 0 || *n_fifo_pairs == 0)
-    return;
-
-  if (rx_fifo_size < FIFO_SEGMENT_MIN_FIFO_SIZE ||
-      rx_fifo_size > FIFO_SEGMENT_MAX_FIFO_SIZE)
-    {
-      clib_warning ("rx fifo_size out of range %d", rx_fifo_size);
-      return;
-    }
-
-  if (tx_fifo_size < FIFO_SEGMENT_MIN_FIFO_SIZE ||
-      tx_fifo_size > FIFO_SEGMENT_MAX_FIFO_SIZE)
-    {
-      clib_warning ("tx fifo_size out of range %d", rx_fifo_size);
-      return;
-    }
-
-  rx_rounded_data_size = (1 << (max_log2 (rx_fifo_size)));
-  rx_freelist_index = max_log2 (rx_fifo_size)
-    - max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE);
-  tx_rounded_data_size = (1 << (max_log2 (tx_fifo_size)));
-  tx_freelist_index = max_log2 (tx_fifo_size)
-    - max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE);
-
-  /* Calculate space requirements */
-  pair_size = 2 * sizeof (*f) + rx_rounded_data_size + tx_rounded_data_size;
-#if USE_DLMALLOC == 0
-  space_available = s->ssvm.ssvm_size - mheap_bytes (sh->heap);
-#else
-  space_available = s->ssvm.ssvm_size - mspace_usable_size (sh->heap);
-#endif
-
-  pairs_to_allocate = clib_min (space_available / pair_size, *n_fifo_pairs);
-  rx_fifos_size = (sizeof (*f) + rx_rounded_data_size) * pairs_to_allocate;
-  tx_fifos_size = (sizeof (*f) + tx_rounded_data_size) * pairs_to_allocate;
-
-  vec_validate_init_empty (fsh->free_fifos,
-			   clib_max (rx_freelist_index, tx_freelist_index),
-			   0);
-
-  oldheap = ssvm_push_heap (sh);
-  /* Allocate rx fifo space. May fail. */
-  rx_fifo_space = clib_mem_alloc_aligned_at_offset
-    (rx_fifos_size, CLIB_CACHE_LINE_BYTES, 0 /* align_offset */ ,
-     0 /* os_out_of_memory */ );
-
-  /* Same for TX */
-  tx_fifo_space = clib_mem_alloc_aligned_at_offset
-    (tx_fifos_size, CLIB_CACHE_LINE_BYTES, 0 /* align_offset */ ,
-     0 /* os_out_of_memory */ );
-
-  /* Make sure it worked. Clean up if it didn't... */
-  if (rx_fifo_space == 0 || tx_fifo_space == 0)
-    {
-      if (rx_fifo_space)
-	clib_mem_free (rx_fifo_space);
-      else
-	clib_warning ("rx fifo preallocation failure: size %d npairs %d",
-		      rx_fifo_size, *n_fifo_pairs);
-
-      if (tx_fifo_space)
-	clib_mem_free (tx_fifo_space);
-      else
-	clib_warning ("tx fifo preallocation failure: size %d nfifos %d",
-		      tx_fifo_size, *n_fifo_pairs);
-      ssvm_pop_heap (oldheap);
-      return;
-    }
-
-  /* Carve rx fifo space */
-  for (i = 0; i < pairs_to_allocate; i++)
-    {
-      fifo_init_for_segment (fsh, rx_fifo_space, rx_rounded_data_size,
-			     rx_freelist_index);
-      rx_fifo_space += sizeof (*f) + rx_rounded_data_size;
-    }
-  /* Carve tx fifo space */
-  for (i = 0; i < pairs_to_allocate; i++)
-    {
-      fifo_init_for_segment (fsh, tx_fifo_space, tx_rounded_data_size,
-			     tx_freelist_index);
-      tx_fifo_space += sizeof (*f) + tx_rounded_data_size;
-    }
-
-  /* Account for the pairs allocated */
-  *n_fifo_pairs -= pairs_to_allocate;
-  ssvm_pop_heap (oldheap);
-}
-
-/**
- * Initialize svm fifo segment shared header
- */
-int
-svm_fifo_segment_init (svm_fifo_segment_private_t * s)
-{
-  svm_fifo_segment_header_t *fsh;
-  ssvm_shared_header_t *sh;
-  void *oldheap;
-
-  sh = s->ssvm.sh;
-  oldheap = ssvm_push_heap (sh);
-
-  fsh = clib_mem_alloc (sizeof (*fsh));
-  clib_memset (fsh, 0, sizeof (*fsh));
-  s->h = sh->opaque[0] = fsh;
-
-  ssvm_pop_heap (oldheap);
-
-  sh->ready = 1;
-  return (0);
-}
-
-/**
- * Create an svm fifo segment and initialize as master
- */
-int
-svm_fifo_segment_create (svm_fifo_segment_main_t * sm,
-			 svm_fifo_segment_create_args_t * a)
-{
-  svm_fifo_segment_private_t *s;
-  int rv;
-
-  /* Allocate a fresh segment */
-  pool_get (sm->segments, s);
-  clib_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 = format (0, "%s%c", a->segment_name, 0);
-  s->ssvm.requested_va = sm->next_baseva;
-
-  if ((rv = ssvm_master_init (&s->ssvm, a->segment_type)))
-    {
-      pool_put (sm->segments, s);
-      return (rv);
-    }
-
-  /* Note: requested_va updated due to seg base addr randomization */
-  sm->next_baseva = s->ssvm.sh->ssvm_va + a->segment_size;
-
-  svm_fifo_segment_init (s);
-  vec_add1 (a->new_segment_indices, s - sm->segments);
-  return (0);
-}
-
-/**
- * Create an svm fifo segment in process-private memory
- */
-int
-svm_fifo_segment_create_process_private (svm_fifo_segment_main_t * sm,
-					 svm_fifo_segment_create_args_t * a)
-{
-  svm_fifo_segment_private_t *s;
-  ssvm_shared_header_t *sh;
-  u32 rnd_size = 0;
-  u8 *heap;
-  u32 pagesize = clib_mem_get_page_size ();
-
-  pool_get (sm->segments, s);
-  clib_memset (s, 0, sizeof (*s));
-
-  rnd_size = (a->segment_size + (pagesize - 1)) & ~pagesize;
-
-#if USE_DLMALLOC == 0
-  heap = mheap_alloc (0, rnd_size);
-  if (heap == 0)
-    {
-      clib_unix_warning ("mheap alloc");
-      pool_put (sm->segments, s);
-      return -1;
-    }
-  {
-    mheap_t *heap_header;
-    heap_header = mheap_header (heap);
-    heap_header->flags |= MHEAP_FLAG_THREAD_SAFE;
-  }
-#else
-  heap = create_mspace (rnd_size, 1 /* locked */ );
-#endif
-
-  s->ssvm.ssvm_size = rnd_size;
-  s->ssvm.i_am_master = 1;
-  s->ssvm.my_pid = getpid ();
-  s->ssvm.name = format (0, "%s%c", a->segment_name, 0);
-  s->ssvm.requested_va = ~0;
-
-  /* Allocate a [sic] shared memory header, in process memory... */
-  sh = clib_mem_alloc_aligned (sizeof (*sh), CLIB_CACHE_LINE_BYTES);
-  s->ssvm.sh = sh;
-
-  clib_memset (sh, 0, sizeof (*sh));
-  sh->heap = heap;
-
-  svm_fifo_segment_init (s);
-  vec_add1 (a->new_segment_indices, s - sm->segments);
-
-  return (0);
-}
-
-/**
- * Attach as slave to an svm fifo segment
- */
-int
-svm_fifo_segment_attach (svm_fifo_segment_main_t * sm,
-			 svm_fifo_segment_create_args_t * a)
-{
-  svm_fifo_segment_private_t *s;
-  int rv;
-
-  /* Allocate a fresh segment */
-  pool_get (sm->segments, s);
-  clib_memset (s, 0, sizeof (*s));
-
-  s->ssvm.ssvm_size = a->segment_size;
-  s->ssvm.my_pid = getpid ();
-  s->ssvm.name = format (0, "%s%c", a->segment_name, 0);
-  s->ssvm.requested_va = sm->next_baseva;
-  if (a->segment_type == SSVM_SEGMENT_MEMFD)
-    s->ssvm.fd = a->memfd_fd;
-  else
-    s->ssvm.attach_timeout = sm->timeout_in_seconds;
-
-  if ((rv = ssvm_slave_init (&s->ssvm, a->segment_type)))
-    {
-      _vec_len (s) = vec_len (s) - 1;
-      return (rv);
-    }
-
-  /* Fish the segment header */
-  s->h = s->ssvm.sh->opaque[0];
-
-  vec_add1 (a->new_segment_indices, s - sm->segments);
-  return (0);
-}
-
-void
-svm_fifo_segment_delete (svm_fifo_segment_main_t * sm,
-			 svm_fifo_segment_private_t * s)
-{
-  ssvm_delete (&s->ssvm);
-  clib_memset (s, 0xfe, sizeof (*s));
-  pool_put (sm->segments, s);
-}
-
-/**
- * Allocate fifo in svm segment
- */
-svm_fifo_t *
-svm_fifo_segment_alloc_fifo (svm_fifo_segment_private_t * fs,
-			     u32 data_size_in_bytes,
-			     svm_fifo_segment_freelist_t list_index)
-{
-  ssvm_shared_header_t *sh;
-  svm_fifo_segment_header_t *fsh;
-  svm_fifo_t *f = 0;
-  void *oldheap;
-  int freelist_index;
-
-  /*
-   * 4K minimum. It's not likely that anything good will happen
-   * with a smaller FIFO.
-   */
-  if (data_size_in_bytes < FIFO_SEGMENT_MIN_FIFO_SIZE ||
-      data_size_in_bytes > FIFO_SEGMENT_MAX_FIFO_SIZE)
-    {
-      clib_warning ("fifo size out of range %d", data_size_in_bytes);
-      return 0;
-    }
-
-  freelist_index = max_log2 (data_size_in_bytes)
-    - max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE);
-
-  sh = fs->ssvm.sh;
-  ssvm_lock_non_recursive (sh, 1);
-  fsh = (svm_fifo_segment_header_t *) sh->opaque[0];
-
-  switch (list_index)
-    {
-    case FIFO_SEGMENT_RX_FREELIST:
-    case FIFO_SEGMENT_TX_FREELIST:
-      vec_validate_init_empty (fsh->free_fifos, freelist_index, 0);
-      f = fsh->free_fifos[freelist_index];
-      if (PREDICT_FALSE (!f))
-	{
-	  oldheap = ssvm_push_heap (sh);
-	  allocate_new_fifo_chunk (fsh, data_size_in_bytes,
-				   FIFO_SEGMENT_ALLOC_CHUNK_SIZE);
-	  ssvm_pop_heap (oldheap);
-	  f = fsh->free_fifos[freelist_index];
-	}
-      if (PREDICT_TRUE (f != 0))
-	{
-	  fsh->free_fifos[freelist_index] = f->next;
-	  /* (re)initialize the fifo, as in svm_fifo_create */
-	  clib_memset (f, 0, sizeof (*f));
-	  svm_fifo_init (f, data_size_in_bytes);
-	  goto found;
-	}
-      break;
-    case FIFO_SEGMENT_FREELIST_NONE:
-      break;
-
-    default:
-      clib_warning ("ignore bogus freelist %d", list_index);
-      break;
-    }
-
-  /* Catch all that allocates just one fifo. Note: this can fail,
-   * in which case: create another segment */
-  oldheap = ssvm_push_heap (sh);
-  f = svm_fifo_create (data_size_in_bytes);
-  ssvm_pop_heap (oldheap);
-  if (PREDICT_FALSE (f == 0))
-    goto done;
-  f->freelist_index = freelist_index;
-
-found:
-  /* If rx_freelist add to active fifos list. When cleaning up segment,
-   * we need a list of active sessions that should be disconnected. Since
-   * both rx and tx fifos keep pointers to the session, it's enough to track
-   * only one. */
-  if (list_index == FIFO_SEGMENT_RX_FREELIST)
-    {
-      if (fsh->fifos)
-	{
-	  fsh->fifos->prev = f;
-	  f->next = fsh->fifos;
-	}
-      fsh->fifos = f;
-    }
-  fsh->n_active_fifos++;
-
-done:
-  ssvm_unlock_non_recursive (sh);
-  return (f);
-}
-
-void
-svm_fifo_segment_free_fifo (svm_fifo_segment_private_t * s, svm_fifo_t * f,
-			    svm_fifo_segment_freelist_t list_index)
-{
-  ssvm_shared_header_t *sh;
-  svm_fifo_segment_header_t *fsh;
-  int freelist_index;
-
-  ASSERT (f->refcnt > 0);
-
-  if (--f->refcnt > 0)
-    return;
-
-  sh = s->ssvm.sh;
-  fsh = (svm_fifo_segment_header_t *) sh->opaque[0];
-
-  freelist_index = f->freelist_index;
-
-  ASSERT (freelist_index < vec_len (fsh->free_fifos));
-
-  ssvm_lock_non_recursive (sh, 2);
-
-  switch (list_index)
-    {
-    case FIFO_SEGMENT_RX_FREELIST:
-      /* Remove from active list */
-      if (f->prev)
-	f->prev->next = f->next;
-      else
-	fsh->fifos = f->next;
-      if (f->next)
-	f->next->prev = f->prev;
-      /* Fall through: we add only rx fifos to active pool */
-    case FIFO_SEGMENT_TX_FREELIST:
-      /* Add to free list */
-      f->next = fsh->free_fifos[freelist_index];
-      f->prev = 0;
-      fsh->free_fifos[freelist_index] = f;
-      break;
-    case FIFO_SEGMENT_FREELIST_NONE:
-      break;
-
-    default:
-      clib_warning ("ignore bogus freelist %d", list_index);
-      break;
-    }
-
-  if (CLIB_DEBUG)
-    {
-      f->master_session_index = ~0;
-      f->master_thread_index = ~0;
-    }
-
-  fsh->n_active_fifos--;
-  ssvm_unlock_non_recursive (sh);
-}
-
-void
-svm_fifo_segment_main_init (svm_fifo_segment_main_t * sm, u64 baseva,
-			    u32 timeout_in_seconds)
-{
-  sm->next_baseva = baseva;
-  sm->timeout_in_seconds = timeout_in_seconds;
-}
-
-u32
-svm_fifo_segment_index (svm_fifo_segment_main_t * sm,
-			svm_fifo_segment_private_t * s)
-{
-  return s - sm->segments;
-}
-
-/**
- * Retrieve svm segments pool. Used only for debug purposes.
- */
-svm_fifo_segment_private_t *
-svm_fifo_segment_segments_pool (svm_fifo_segment_main_t * sm)
-{
-  return sm->segments;
-}
-
-/**
- * Get number of active fifos
- */
-u32
-svm_fifo_segment_num_fifos (svm_fifo_segment_private_t * fifo_segment)
-{
-  return fifo_segment->h->n_active_fifos;
-}
-
-u32
-svm_fifo_segment_num_free_fifos (svm_fifo_segment_private_t * fifo_segment,
-				 u32 fifo_size_in_bytes)
-{
-  ssvm_shared_header_t *sh;
-  svm_fifo_segment_header_t *fsh;
-  svm_fifo_t *f;
-  int i;
-  u32 count = 0, rounded_data_size, freelist_index;
-
-  sh = fifo_segment->ssvm.sh;
-  fsh = (svm_fifo_segment_header_t *) sh->opaque[0];
-
-  /* Count all free fifos? */
-  if (fifo_size_in_bytes == ~0)
-    {
-      for (i = 0; i < vec_len (fsh->free_fifos); i++)
-	{
-	  f = fsh->free_fifos[i];
-	  if (f == 0)
-	    continue;
-
-	  while (f)
-	    {
-	      f = f->next;
-	      count++;
-	    }
-	}
-      return count;
-    }
-
-  rounded_data_size = (1 << (max_log2 (fifo_size_in_bytes)));
-  freelist_index = max_log2 (rounded_data_size)
-    - max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE);
-
-  if (freelist_index >= vec_len (fsh->free_fifos))
-    return 0;
-
-  f = fsh->free_fifos[freelist_index];
-  if (f == 0)
-    return 0;
-
-  while (f)
-    {
-      f = f->next;
-      count++;
-    }
-  return count;
-}
-
-void
-svm_fifo_segment_info (svm_fifo_segment_private_t * seg, char **address,
-		       size_t * size)
-{
-  if (ssvm_type (&seg->ssvm) == SSVM_SEGMENT_PRIVATE)
-    {
-#if USE_DLMALLOC == 0
-      mheap_t *heap_header;
-
-      *address = pointer_to_uword (seg->ssvm.sh->heap);
-      heap_header = mheap_header (seg->ssvm.sh->heap);
-      *size = heap_header->max_size;
-#else
-      mspace_get_address_and_size (seg->ssvm.sh->heap, address, size);
-#endif
-    }
-  else
-    {
-      *address = (char *) seg->ssvm.sh->ssvm_va;
-      *size = seg->ssvm.ssvm_size;
-    }
-}
-
-void *
-svm_fifo_segment_heap (svm_fifo_segment_private_t * seg)
-{
-  return seg->ssvm.sh->heap;
-}
-
-u8 *
-format_svm_fifo_segment_type (u8 * s, va_list * args)
-{
-  svm_fifo_segment_private_t *sp;
-  sp = va_arg (*args, svm_fifo_segment_private_t *);
-  ssvm_segment_type_t st = ssvm_type (&sp->ssvm);
-
-  if (st == SSVM_SEGMENT_PRIVATE)
-    s = format (s, "%s", "private-heap");
-  else if (st == SSVM_SEGMENT_MEMFD)
-    s = format (s, "%s", "memfd");
-  else if (st == SSVM_SEGMENT_SHM)
-    s = format (s, "%s", "shm");
-  else
-    s = format (s, "%s", "unknown");
-  return s;
-}
-
-/**
- * Segment format function
- */
-u8 *
-format_svm_fifo_segment (u8 * s, va_list * args)
-{
-  svm_fifo_segment_private_t *sp
-    = va_arg (*args, svm_fifo_segment_private_t *);
-  int verbose __attribute__ ((unused)) = va_arg (*args, int);
-  svm_fifo_segment_header_t *fsh = sp->h;
-  u32 count, indent;
-  svm_fifo_t *f;
-  int i;
-
-  indent = format_get_indent (s) + 2;
-#if USE_DLMALLOC == 0
-  s = format (s, "%U segment heap: %U\n", format_white_space, indent,
-	      format_mheap, svm_fifo_segment_heap (sp), verbose);
-  s = format (s, "%U segment has %u active fifos\n",
-	      format_white_space, indent, svm_fifo_segment_num_fifos (sp));
-#endif
-
-  for (i = 0; i < vec_len (fsh->free_fifos); i++)
-    {
-      f = fsh->free_fifos[i];
-      if (f == 0)
-	continue;
-      count = 0;
-      while (f)
-	{
-	  f = f->next;
-	  count++;
-	}
-
-      s = format (s, "%U%-5u Kb: %u free",
-		  format_white_space, indent + 2,
-		  1 << (i + max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE) - 10),
-		  count);
-    }
-  return s;
-}
-
-/*
- * 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
deleted file mode 100644
index d4d4809..0000000
--- a/src/svm/svm_fifo_segment.h
+++ /dev/null
@@ -1,136 +0,0 @@
-/*
- * Copyright (c) 2016-2019 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/ssvm.h>
-#include <svm/svm_fifo.h>
-#include <vppinfra/lock.h>
-
-typedef enum
-{
-  FIFO_SEGMENT_FREELIST_NONE = -1,
-  FIFO_SEGMENT_RX_FREELIST = 0,
-  FIFO_SEGMENT_TX_FREELIST,
-  FIFO_SEGMENT_N_FREELISTS
-} svm_fifo_segment_freelist_t;
-
-#define FIFO_SEGMENT_MIN_FIFO_SIZE 4096
-#define FIFO_SEGMENT_MAX_FIFO_SIZE (2 << 30)	/* 2GB max fifo size */
-#define FIFO_SEGMENT_ALLOC_CHUNK_SIZE 32	/* Allocation quantum */
-
-#define FIFO_SEGMENT_F_IS_PREALLOCATED	(1 << 0)
-#define FIFO_SEGMENT_F_WILL_DELETE	(1 << 1)
-
-typedef struct
-{
-  svm_fifo_t *fifos;		/**< Linked list of active RX fifos */
-  svm_fifo_t **free_fifos;	/**< Freelists, by fifo size  */
-  u32 n_active_fifos;		/**< Number of active fifos */
-  u8 flags;			/**< Segment flags */
-} svm_fifo_segment_header_t;
-
-typedef struct
-{
-  ssvm_private_t ssvm;
-  svm_fifo_segment_header_t *h;
-} svm_fifo_segment_private_t;
-
-typedef struct
-{
-  volatile u32 lock;
-
-  /** 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;
-
-typedef struct
-{
-  ssvm_segment_type_t segment_type;
-  char *segment_name;
-  u32 segment_size;
-  u32 *new_segment_indices;
-  int memfd_fd;
-} svm_fifo_segment_create_args_t;
-
-#define svm_fifo_segment_flags(_seg) _seg->h->flags
-
-static inline svm_fifo_segment_private_t *
-svm_fifo_segment_get_segment (svm_fifo_segment_main_t * sm, u32 segment_index)
-{
-  return pool_elt_at_index (sm->segments, segment_index);
-}
-
-static inline u8
-svm_fifo_segment_has_fifos (svm_fifo_segment_private_t * fifo_segment)
-{
-  return fifo_segment->h->fifos != 0;
-}
-
-static inline svm_fifo_t *
-svm_fifo_segment_get_fifo_list (svm_fifo_segment_private_t * fifo_segment)
-{
-  return fifo_segment->h->fifos;
-}
-
-int svm_fifo_segment_init (svm_fifo_segment_private_t * s);
-int svm_fifo_segment_create (svm_fifo_segment_main_t * sm,
-			     svm_fifo_segment_create_args_t * a);
-int svm_fifo_segment_create_process_private (svm_fifo_segment_main_t * sm,
-					     svm_fifo_segment_create_args_t
-					     *);
-void svm_fifo_segment_preallocate_fifo_pairs (svm_fifo_segment_private_t * s,
-					      u32 rx_fifo_size,
-					      u32 tx_fifo_size,
-					      u32 * n_fifo_pairs);
-int svm_fifo_segment_attach (svm_fifo_segment_main_t * sm,
-			     svm_fifo_segment_create_args_t * a);
-void svm_fifo_segment_delete (svm_fifo_segment_main_t * sm,
-			      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,
-					 svm_fifo_segment_freelist_t index);
-void svm_fifo_segment_free_fifo (svm_fifo_segment_private_t * s,
-				 svm_fifo_t * f,
-				 svm_fifo_segment_freelist_t index);
-void svm_fifo_segment_main_init (svm_fifo_segment_main_t * sm, u64 baseva,
-				 u32 timeout_in_seconds);
-u32 svm_fifo_segment_index (svm_fifo_segment_main_t * sm,
-			    svm_fifo_segment_private_t * s);
-u32 svm_fifo_segment_num_fifos (svm_fifo_segment_private_t * fifo_segment);
-u32 svm_fifo_segment_num_free_fifos (svm_fifo_segment_private_t *
-				     fifo_segment, u32 fifo_size_in_bytes);
-void svm_fifo_segment_info (svm_fifo_segment_private_t * seg, char **address,
-			    size_t * size);
-
-svm_fifo_segment_private_t
-  * svm_fifo_segment_segments_pool (svm_fifo_segment_main_t * sm);
-
-format_function_t format_svm_fifo_segment;
-format_function_t format_svm_fifo_segment_type;
-
-#endif /* __included_ssvm_fifo_segment_h__ */
-
-/*
- * fd.io coding-style-patch-verification: ON
- *
- * Local Variables:
- * eval: (c-set-style "gnu")
- * End:
- */