stats: refactor

Type: refactor
Change-Id: Ifd533a095d979dc55bfbe5fac7e0b7510a4d900c
Signed-off-by: Damjan Marion <damarion@cisco.com>

8 files changed, 1381 insertions, 0 deletions

diff --git a/src/vlib/stats/cli.c b/src/vlib/stats/cli.c
new file mode 100644
index 00000000000..4d7026b5995
--- /dev/null
+++ b/src/vlib/stats/cli.c
@@ -0,0 +1,125 @@
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright(c) 2022 Cisco Systems, Inc.
+ */
+
+#include <vlib/vlib.h>
+#include <vlib/stats/stats.h>
+
+static int
+name_sort_cmp (void *a1, void *a2)
+{
+  vlib_stats_entry_t *n1 = a1;
+  vlib_stats_entry_t *n2 = a2;
+
+  return strcmp ((char *) n1->name, (char *) n2->name);
+}
+
+static u8 *
+format_stat_dir_entry (u8 *s, va_list *args)
+{
+  vlib_stats_entry_t *ep = va_arg (*args, vlib_stats_entry_t *);
+  char *type_name;
+  char *format_string;
+
+  format_string = "%-74s %-10s %10lld";
+
+  switch (ep->type)
+    {
+    case STAT_DIR_TYPE_SCALAR_INDEX:
+      type_name = "ScalarPtr";
+      break;
+
+    case STAT_DIR_TYPE_COUNTER_VECTOR_SIMPLE:
+    case STAT_DIR_TYPE_COUNTER_VECTOR_COMBINED:
+      type_name = "CMainPtr";
+      break;
+
+    case STAT_DIR_TYPE_ERROR_INDEX:
+      type_name = "ErrIndex";
+      break;
+
+    case STAT_DIR_TYPE_NAME_VECTOR:
+      type_name = "NameVector";
+      break;
+
+    case STAT_DIR_TYPE_EMPTY:
+      type_name = "empty";
+      break;
+
+    case STAT_DIR_TYPE_SYMLINK:
+      type_name = "Symlink";
+      break;
+
+    default:
+      type_name = "illegal!";
+      break;
+    }
+
+  return format (s, format_string, ep->name, type_name, 0);
+}
+static clib_error_t *
+show_stat_segment_command_fn (vlib_main_t *vm, unformat_input_t *input,
+			      vlib_cli_command_t *cmd)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  vlib_stats_entry_t *show_data;
+  int i;
+
+  int verbose = 0;
+
+  if (unformat (input, "verbose"))
+    verbose = 1;
+
+  /* Lock even as reader, as this command doesn't handle epoch changes */
+  vlib_stats_segment_lock ();
+  show_data = vec_dup (sm->directory_vector);
+  vlib_stats_segment_unlock ();
+
+  vec_sort_with_function (show_data, name_sort_cmp);
+
+  vlib_cli_output (vm, "%-74s %10s %10s", "Name", "Type", "Value");
+
+  for (i = 0; i < vec_len (show_data); i++)
+    {
+      vlib_stats_entry_t *ep = vec_elt_at_index (show_data, i);
+
+      if (ep->type == STAT_DIR_TYPE_EMPTY)
+	continue;
+
+      vlib_cli_output (vm, "%-100U", format_stat_dir_entry,
+		       vec_elt_at_index (show_data, i));
+    }
+
+  if (verbose)
+    {
+      ASSERT (sm->heap);
+      vlib_cli_output (vm, "%U", format_clib_mem_heap, sm->heap,
+		       0 /* verbose */);
+    }
+
+  return 0;
+}
+
+static clib_error_t *
+show_stat_segment_hash_command_fn (vlib_main_t *vm, unformat_input_t *input,
+				   vlib_cli_command_t *cmd)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  char *name;
+  u32 i;
+  hash_foreach_mem (name, i, sm->directory_vector_by_name,
+		    ({ vlib_cli_output (vm, "%d: %s\n", i, name); }));
+  return 0;
+}
+
+VLIB_CLI_COMMAND (show_stat_segment_hash_command, static) = {
+  .path = "show statistics hash",
+  .short_help = "show statistics hash",
+  .function = show_stat_segment_hash_command_fn,
+};
+
+VLIB_CLI_COMMAND (show_stat_segment_command, static) = {
+  .path = "show statistics segment",
+  .short_help = "show statistics segment [verbose]",
+  .function = show_stat_segment_command_fn,
+};
diff --git a/src/vlib/stats/collector.c b/src/vlib/stats/collector.c
new file mode 100644
index 00000000000..cc348bbf3ad
--- /dev/null
+++ b/src/vlib/stats/collector.c
@@ -0,0 +1,192 @@
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright(c) 2022 Cisco Systems, Inc.
+ */
+
+#include <vlib/vlib.h>
+#include <vlib/unix/unix.h>
+#include <vlib/stats/stats.h>
+
+static void
+stat_validate_counter_vector2 (vlib_stats_entry_t *ep, u32 max1, u32 max2)
+{
+  counter_t **counters = ep->data;
+  int i;
+  vec_validate_aligned (counters, max1, CLIB_CACHE_LINE_BYTES);
+  for (i = 0; i <= max1; i++)
+    vec_validate_aligned (counters[i], max2, CLIB_CACHE_LINE_BYTES);
+
+  ep->data = counters;
+}
+
+static void
+stat_validate_counter_vector (vlib_stats_entry_t *ep, u32 max)
+{
+  vlib_thread_main_t *tm = vlib_get_thread_main ();
+  ASSERT (tm->n_vlib_mains > 0);
+  stat_validate_counter_vector2 (ep, tm->n_vlib_mains, max);
+}
+
+static inline void
+update_node_counters (vlib_stats_segment_t *sm)
+{
+  vlib_main_t **stat_vms = 0;
+  vlib_node_t ***node_dups = 0;
+  int i, j;
+  static u32 no_max_nodes = 0;
+
+  vlib_node_get_nodes (0 /* vm, for barrier sync */,
+		       (u32) ~0 /* all threads */, 1 /* include stats */,
+		       0 /* barrier sync */, &node_dups, &stat_vms);
+
+  u32 l = vec_len (node_dups[0]);
+  u8 *symlink_name = 0;
+
+  /*
+   * Extend performance nodes if necessary
+   */
+  if (l > no_max_nodes)
+    {
+      void *oldheap = clib_mem_set_heap (sm->heap);
+      vlib_stats_segment_lock ();
+
+      stat_validate_counter_vector (
+	&sm->directory_vector[STAT_COUNTER_NODE_CLOCKS], l - 1);
+      stat_validate_counter_vector (
+	&sm->directory_vector[STAT_COUNTER_NODE_VECTORS], l - 1);
+      stat_validate_counter_vector (
+	&sm->directory_vector[STAT_COUNTER_NODE_CALLS], l - 1);
+      stat_validate_counter_vector (
+	&sm->directory_vector[STAT_COUNTER_NODE_SUSPENDS], l - 1);
+
+      vec_validate (sm->nodes, l - 1);
+      vlib_stats_entry_t *ep;
+      ep = &sm->directory_vector[STAT_COUNTER_NODE_NAMES];
+      ep->data = sm->nodes;
+
+      /* Update names dictionary */
+      vlib_node_t **nodes = node_dups[0];
+      int i;
+      for (i = 0; i < vec_len (nodes); i++)
+	{
+	  vlib_node_t *n = nodes[i];
+	  u8 *s = format (0, "%v%c", n->name, 0);
+	  if (sm->nodes[n->index])
+	    vec_free (sm->nodes[n->index]);
+	  sm->nodes[n->index] = s;
+
+	  oldheap = clib_mem_set_heap (oldheap);
+#define _(E, t, name, p)                                                      \
+  vlib_stats_add_symlink (STAT_COUNTER_##E, n->index, "/nodes/%U/" #name,     \
+			  format_vlib_stats_symlink, s);
+	  foreach_stat_segment_node_counter_name
+#undef _
+	    oldheap = clib_mem_set_heap (oldheap);
+	}
+
+      vlib_stats_segment_unlock ();
+      clib_mem_set_heap (oldheap);
+      no_max_nodes = l;
+    }
+
+  for (j = 0; j < vec_len (node_dups); j++)
+    {
+      vlib_node_t **nodes = node_dups[j];
+
+      for (i = 0; i < vec_len (nodes); i++)
+	{
+	  counter_t **counters;
+	  counter_t *c;
+	  vlib_node_t *n = nodes[i];
+
+	  if (j == 0)
+	    {
+	      if (strncmp ((char *) sm->nodes[n->index], (char *) n->name,
+			   strlen ((char *) sm->nodes[n->index])))
+		{
+		  u32 vector_index;
+		  void *oldheap = clib_mem_set_heap (sm->heap);
+		  vlib_stats_segment_lock ();
+		  u8 *s = format (0, "%v%c", n->name, 0);
+		  clib_mem_set_heap (oldheap);
+#define _(E, t, name, p)                                                      \
+  vec_reset_length (symlink_name);                                            \
+  symlink_name = format (symlink_name, "/nodes/%U/" #name,                    \
+			 format_vlib_stats_symlink, sm->nodes[n->index]);     \
+  vector_index = vlib_stats_find_entry_index ("%v", symlink_name);            \
+  ASSERT (vector_index != -1);                                                \
+  vlib_stats_rename_symlink (vector_index, "/nodes/%U/" #name,                \
+			     format_vlib_stats_symlink, s);
+		  foreach_stat_segment_node_counter_name
+#undef _
+		    vec_free (symlink_name);
+		  clib_mem_set_heap (sm->heap);
+		  vec_free (sm->nodes[n->index]);
+		  sm->nodes[n->index] = s;
+		  vlib_stats_segment_unlock ();
+		  clib_mem_set_heap (oldheap);
+		}
+	    }
+
+	  counters = sm->directory_vector[STAT_COUNTER_NODE_CLOCKS].data;
+	  c = counters[j];
+	  c[n->index] = n->stats_total.clocks - n->stats_last_clear.clocks;
+
+	  counters = sm->directory_vector[STAT_COUNTER_NODE_VECTORS].data;
+	  c = counters[j];
+	  c[n->index] = n->stats_total.vectors - n->stats_last_clear.vectors;
+
+	  counters = sm->directory_vector[STAT_COUNTER_NODE_CALLS].data;
+	  c = counters[j];
+	  c[n->index] = n->stats_total.calls - n->stats_last_clear.calls;
+
+	  counters = sm->directory_vector[STAT_COUNTER_NODE_SUSPENDS].data;
+	  c = counters[j];
+	  c[n->index] = n->stats_total.suspends - n->stats_last_clear.suspends;
+	}
+      vec_free (node_dups[j]);
+    }
+  vec_free (node_dups);
+  vec_free (stat_vms);
+}
+
+static void
+do_stat_segment_updates (vlib_main_t *vm, vlib_stats_segment_t *sm)
+{
+  if (sm->node_counters_enabled)
+    update_node_counters (sm);
+
+  vlib_stats_collector_t *c;
+  pool_foreach (c, sm->collectors)
+    {
+      vlib_stats_collector_data_t data = {
+	.entry_index = c->entry_index,
+	.vector_index = c->vector_index,
+	.private_data = c->private_data,
+	.entry = sm->directory_vector + c->entry_index,
+      };
+      c->fn (&data);
+    }
+
+  /* Heartbeat, so clients detect we're still here */
+  sm->directory_vector[STAT_COUNTER_HEARTBEAT].value++;
+}
+
+static uword
+stat_segment_collector_process (vlib_main_t *vm, vlib_node_runtime_t *rt,
+				vlib_frame_t *f)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+
+  while (1)
+    {
+      do_stat_segment_updates (vm, sm);
+      vlib_process_suspend (vm, sm->update_interval);
+    }
+  return 0; /* or not */
+}
+
+VLIB_REGISTER_NODE (stat_segment_collector, static) = {
+  .function = stat_segment_collector_process,
+  .name = "statseg-collector-process",
+  .type = VLIB_NODE_TYPE_PROCESS,
+};
diff --git a/src/vlib/stats/format.c b/src/vlib/stats/format.c
new file mode 100644
index 00000000000..419ff6b4657
--- /dev/null
+++ b/src/vlib/stats/format.c
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright(c) 2022 Cisco Systems, Inc.
+ */
+
+#include <vlib/vlib.h>
+#include <vlib/unix/unix.h>
+#include <vlib/stats/stats.h>
+
+u8 *
+format_vlib_stats_symlink (u8 *s, va_list *args)
+{
+  char *input = va_arg (*args, char *);
+  char *modified_input = vec_dup (input);
+  int i;
+  u8 *result;
+
+  for (i = 0; i < strlen (modified_input); i++)
+    if (modified_input[i] == '/')
+      modified_input[i] = '_';
+
+  result = format (s, "%s", modified_input);
+  vec_free (modified_input);
+  return result;
+}
diff --git a/src/vlib/stats/init.c b/src/vlib/stats/init.c
new file mode 100644
index 00000000000..d81916a288d
--- /dev/null
+++ b/src/vlib/stats/init.c
@@ -0,0 +1,246 @@
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright(c) 2022 Cisco Systems, Inc.
+ */
+
+#include <vlib/vlib.h>
+#include <vlib/unix/unix.h>
+#include <vlib/stats/stats.h>
+
+#define STAT_SEGMENT_SOCKET_FILENAME "stats.sock"
+
+static void
+vector_rate_collector_fn (vlib_stats_collector_data_t *d)
+{
+  vlib_main_t *this_vlib_main;
+  counter_t **counters = d->entry->data;
+  counter_t *cb = counters[0];
+  f64 vector_rate = 0.0;
+  u32 i, n_threads = vlib_get_n_threads ();
+
+  vlib_stats_validate_counter_vector (d->entry_index, n_threads - 1);
+
+  for (i = 0; i < n_threads; i++)
+    {
+      f64 this_vector_rate;
+      this_vlib_main = vlib_get_main_by_index (i);
+
+      this_vector_rate = vlib_internal_node_vector_rate (this_vlib_main);
+      vlib_clear_internal_node_vector_rate (this_vlib_main);
+
+      cb[i] = this_vector_rate;
+      vector_rate += this_vector_rate;
+    }
+
+  /* And set the system average rate */
+  vector_rate /= (f64) (i > 1 ? i - 1 : 1);
+  vlib_stats_set_gauge (d->private_data, vector_rate);
+}
+
+clib_error_t *
+vlib_stats_init (vlib_main_t *vm)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  vlib_stats_shared_header_t *shared_header;
+  vlib_stats_collector_reg_t reg = {};
+
+  void *oldheap;
+  uword memory_size, sys_page_sz;
+  int mfd;
+  char *mem_name = "stat segment";
+  void *heap, *memaddr;
+
+  memory_size = sm->memory_size;
+  if (memory_size == 0)
+    memory_size = STAT_SEGMENT_DEFAULT_SIZE;
+
+  if (sm->log2_page_sz == CLIB_MEM_PAGE_SZ_UNKNOWN)
+    sm->log2_page_sz = CLIB_MEM_PAGE_SZ_DEFAULT;
+
+  mfd = clib_mem_vm_create_fd (sm->log2_page_sz, mem_name);
+
+  if (mfd == -1)
+    return clib_error_return (0, "stat segment memory fd failure: %U",
+			      format_clib_error, clib_mem_get_last_error ());
+  /* Set size */
+  if ((ftruncate (mfd, memory_size)) == -1)
+    {
+      close (mfd);
+      return clib_error_return (0, "stat segment ftruncate failure");
+    }
+
+  memaddr = clib_mem_vm_map_shared (0, memory_size, mfd, 0, mem_name);
+
+  if (memaddr == CLIB_MEM_VM_MAP_FAILED)
+    return clib_error_return (0, "stat segment mmap failure");
+
+  sys_page_sz = clib_mem_get_page_size ();
+
+  heap =
+    clib_mem_create_heap (((u8 *) memaddr) + sys_page_sz,
+			  memory_size - sys_page_sz, 1 /* locked */, mem_name);
+  sm->heap = heap;
+  sm->memfd = mfd;
+
+  sm->directory_vector_by_name = hash_create_string (0, sizeof (uword));
+  sm->shared_header = shared_header = memaddr;
+
+  shared_header->version = STAT_SEGMENT_VERSION;
+  shared_header->base = memaddr;
+
+  sm->stat_segment_lockp = clib_mem_alloc (sizeof (clib_spinlock_t));
+  clib_spinlock_init (sm->stat_segment_lockp);
+
+  oldheap = clib_mem_set_heap (sm->heap);
+
+  /* Set up the name to counter-vector hash table */
+  sm->directory_vector = 0;
+
+  shared_header->epoch = 1;
+
+  /* Scalar stats and node counters */
+  vec_validate (sm->directory_vector, STAT_COUNTERS - 1);
+#define _(E, t, n, p)                                                         \
+  strcpy (sm->directory_vector[STAT_COUNTER_##E].name, p "/" #n);             \
+  sm->directory_vector[STAT_COUNTER_##E].type = STAT_DIR_TYPE_##t;
+  foreach_stat_segment_counter_name
+#undef _
+    /* Save the vector in the shared segment, for clients */
+    shared_header->directory_vector = sm->directory_vector;
+
+  clib_mem_set_heap (oldheap);
+
+  vlib_stats_register_mem_heap (heap);
+
+  reg.collect_fn = vector_rate_collector_fn;
+  reg.private_data = vlib_stats_add_gauge ("/sys/vector_rate");
+  reg.entry_index =
+    vlib_stats_add_counter_vector ("/sys/vector_rate_per_worker");
+  vlib_stats_register_collector_fn (&reg);
+  vlib_stats_validate_counter_vector (reg.entry_index, vlib_get_n_threads ());
+
+  return 0;
+}
+
+static clib_error_t *
+statseg_config (vlib_main_t *vm, unformat_input_t *input)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  sm->update_interval = 10.0;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "socket-name %s", &sm->socket_name))
+	;
+      /* DEPRECATE: default (does nothing) */
+      else if (unformat (input, "default"))
+	;
+      else if (unformat (input, "size %U", unformat_memory_size,
+			 &sm->memory_size))
+	;
+      else if (unformat (input, "page-size %U", unformat_log2_page_size,
+			 &sm->log2_page_sz))
+	;
+      else if (unformat (input, "per-node-counters on"))
+	sm->node_counters_enabled = 1;
+      else if (unformat (input, "per-node-counters off"))
+	sm->node_counters_enabled = 0;
+      else if (unformat (input, "update-interval %f", &sm->update_interval))
+	;
+      else
+	return clib_error_return (0, "unknown input `%U'",
+				  format_unformat_error, input);
+    }
+
+  /*
+   * NULL-terminate socket name string
+   * clib_socket_init()->socket_config() use C str*
+   */
+  if (vec_len (sm->socket_name))
+    vec_terminate_c_string (sm->socket_name);
+
+  return 0;
+}
+
+VLIB_EARLY_CONFIG_FUNCTION (statseg_config, "statseg");
+
+/*
+ * Accept connection on the socket and exchange the fd for the shared
+ * memory segment.
+ */
+static clib_error_t *
+stats_socket_accept_ready (clib_file_t *uf)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  clib_error_t *err;
+  clib_socket_t client = { 0 };
+
+  err = clib_socket_accept (sm->socket, &client);
+  if (err)
+    {
+      clib_error_report (err);
+      return err;
+    }
+
+  /* Send the fd across and close */
+  err = clib_socket_sendmsg (&client, 0, 0, &sm->memfd, 1);
+  if (err)
+    clib_error_report (err);
+  clib_socket_close (&client);
+
+  return 0;
+}
+
+static clib_error_t *
+stats_segment_socket_init (void)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  clib_error_t *error;
+  clib_socket_t *s = clib_mem_alloc (sizeof (clib_socket_t));
+
+  memset (s, 0, sizeof (clib_socket_t));
+  s->config = (char *) sm->socket_name;
+  s->flags = CLIB_SOCKET_F_IS_SERVER | CLIB_SOCKET_F_SEQPACKET |
+	     CLIB_SOCKET_F_ALLOW_GROUP_WRITE | CLIB_SOCKET_F_PASSCRED;
+
+  if ((error = clib_socket_init (s)))
+    return error;
+
+  clib_file_t template = { 0 };
+  template.read_function = stats_socket_accept_ready;
+  template.file_descriptor = s->fd;
+  template.description = format (0, "stats segment listener %s", s->config);
+  clib_file_add (&file_main, &template);
+
+  sm->socket = s;
+
+  return 0;
+}
+
+static clib_error_t *
+stats_segment_socket_exit (vlib_main_t *vm)
+{
+  /*
+   * cleanup the listener socket on exit.
+   */
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  unlink ((char *) sm->socket_name);
+  return 0;
+}
+
+VLIB_MAIN_LOOP_EXIT_FUNCTION (stats_segment_socket_exit);
+
+static clib_error_t *
+statseg_init (vlib_main_t *vm)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+
+  /* set default socket file name when statseg config stanza is empty. */
+  if (!vec_len (sm->socket_name))
+    sm->socket_name = format (0, "%s/%s%c", vlib_unix_get_runtime_dir (),
+			      STAT_SEGMENT_SOCKET_FILENAME, 0);
+  return stats_segment_socket_init ();
+}
+
+VLIB_INIT_FUNCTION (statseg_init) = {
+  .runs_after = VLIB_INITS ("unix_input_init", "linux_epoll_input_init"),
+};
diff --git a/src/vlib/stats/provider_mem.c b/src/vlib/stats/provider_mem.c
new file mode 100644
index 00000000000..d52ea4aa0e5
--- /dev/null
+++ b/src/vlib/stats/provider_mem.c
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright(c) 2022 Cisco Systems, Inc.
+ */
+
+#include <vlib/vlib.h>
+#include <vlib/unix/unix.h>
+#include <vlib/stats/stats.h>
+
+static clib_mem_heap_t **memory_heaps_vec;
+
+enum
+{
+  STAT_MEM_TOTAL = 0,
+  STAT_MEM_USED,
+  STAT_MEM_FREE,
+  STAT_MEM_USED_MMAP,
+  STAT_MEM_TOTAL_ALLOC,
+  STAT_MEM_FREE_CHUNKS,
+  STAT_MEM_RELEASABLE,
+} stat_mem_usage_e;
+
+/*
+ * Called from the stats periodic process to update memory counters.
+ */
+static void
+stat_provider_mem_usage_update_fn (vlib_stats_collector_data_t *d)
+{
+  clib_mem_usage_t usage;
+  clib_mem_heap_t *heap;
+  counter_t **counters = d->entry->data;
+  counter_t *cb;
+
+  heap = vec_elt (memory_heaps_vec, d->private_data);
+  clib_mem_get_heap_usage (heap, &usage);
+  cb = counters[0];
+  cb[STAT_MEM_TOTAL] = usage.bytes_total;
+  cb[STAT_MEM_USED] = usage.bytes_used;
+  cb[STAT_MEM_FREE] = usage.bytes_free;
+  cb[STAT_MEM_USED_MMAP] = usage.bytes_used_mmap;
+  cb[STAT_MEM_TOTAL_ALLOC] = usage.bytes_max;
+  cb[STAT_MEM_FREE_CHUNKS] = usage.bytes_free_reclaimed;
+  cb[STAT_MEM_RELEASABLE] = usage.bytes_overhead;
+}
+
+/*
+ * Provide memory heap counters.
+ * Two dimensional array of heap index and per-heap gauges.
+ */
+void
+vlib_stats_register_mem_heap (clib_mem_heap_t *heap)
+{
+  vlib_stats_collector_reg_t r = {};
+  u32 idx;
+
+  vec_add1 (memory_heaps_vec, heap);
+
+  r.entry_index = idx = vlib_stats_add_counter_vector ("/mem/%s", heap->name);
+  vlib_stats_validate_counter_vector (idx, STAT_MEM_RELEASABLE);
+
+  /* Create symlink */
+  vlib_stats_add_symlink (idx, STAT_MEM_TOTAL, "/mem/%s/used", heap->name);
+  vlib_stats_add_symlink (idx, STAT_MEM_USED, "/mem/%s/total", heap->name);
+  vlib_stats_add_symlink (idx, STAT_MEM_FREE, "/mem/%s/free", heap->name);
+
+  r.private_data = vec_len (memory_heaps_vec) - 1;
+  r.collect_fn = stat_provider_mem_usage_update_fn;
+  vlib_stats_register_collector_fn (&r);
+}
diff --git a/src/vlib/stats/shared.h b/src/vlib/stats/shared.h
new file mode 100644
index 00000000000..d2d5d49cc54
--- /dev/null
+++ b/src/vlib/stats/shared.h
@@ -0,0 +1,52 @@
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright(c) 2022 Cisco Systems, Inc.
+ */
+
+#ifndef included_stat_segment_shared_h
+#define included_stat_segment_shared_h
+
+typedef enum
+{
+  STAT_DIR_TYPE_ILLEGAL = 0,
+  STAT_DIR_TYPE_SCALAR_INDEX,
+  STAT_DIR_TYPE_COUNTER_VECTOR_SIMPLE,
+  STAT_DIR_TYPE_COUNTER_VECTOR_COMBINED,
+  STAT_DIR_TYPE_ERROR_INDEX,
+  STAT_DIR_TYPE_NAME_VECTOR,
+  STAT_DIR_TYPE_EMPTY,
+  STAT_DIR_TYPE_SYMLINK,
+} stat_directory_type_t;
+
+typedef struct
+{
+  stat_directory_type_t type;
+  union
+  {
+    struct
+    {
+      uint32_t index1;
+      uint32_t index2;
+    };
+    uint64_t index;
+    uint64_t value;
+    void *data;
+    uint8_t **string_vector;
+  };
+#define VLIB_STATS_MAX_NAME_SZ 128
+  char name[VLIB_STATS_MAX_NAME_SZ];
+} vlib_stats_entry_t;
+
+/*
+ * Shared header first in the shared memory segment.
+ */
+typedef struct
+{
+  uint64_t version;
+  void *base;
+  volatile uint64_t epoch;
+  volatile uint64_t in_progress;
+  volatile vlib_stats_entry_t *directory_vector;
+  volatile uint64_t **error_vector;
+} vlib_stats_shared_header_t;
+
+#endif /* included_stat_segment_shared_h */
diff --git a/src/vlib/stats/stats.c b/src/vlib/stats/stats.c
new file mode 100644
index 00000000000..19edaf0866d
--- /dev/null
+++ b/src/vlib/stats/stats.c
@@ -0,0 +1,514 @@
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright(c) 2022 Cisco Systems, Inc.
+ */
+
+#include <vlib/vlib.h>
+#include <vlib/stats/stats.h>
+
+vlib_stats_main_t vlib_stats_main;
+
+/*
+ *  Used only by VPP writers
+ */
+
+void
+vlib_stats_segment_lock (void)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  clib_spinlock_lock (sm->stat_segment_lockp);
+  sm->shared_header->in_progress = 1;
+}
+
+void
+vlib_stats_segment_unlock (void)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  sm->shared_header->epoch++;
+  sm->shared_header->in_progress = 0;
+  clib_spinlock_unlock (sm->stat_segment_lockp);
+}
+
+/*
+ * Change heap to the stats shared memory segment
+ */
+void *
+vlib_stats_set_heap ()
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+
+  ASSERT (sm && sm->shared_header);
+  return clib_mem_set_heap (sm->heap);
+}
+
+u32
+vlib_stats_find_entry_index (char *fmt, ...)
+{
+  u8 *name;
+  va_list va;
+
+  va_start (va, fmt);
+  name = va_format (0, fmt, &va);
+  va_end (va);
+  vec_add1 (name, 0);
+
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  hash_pair_t *hp = hash_get_pair (sm->directory_vector_by_name, name);
+  vec_free (name);
+  return hp ? hp->value[0] : STAT_SEGMENT_INDEX_INVALID;
+}
+
+static void
+hash_set_str_key_alloc (uword **h, const char *key, uword v)
+{
+  int size = strlen (key) + 1;
+  void *copy = clib_mem_alloc (size);
+  clib_memcpy_fast (copy, key, size);
+  hash_set_mem (*h, copy, v);
+}
+
+static void
+hash_unset_str_key_free (uword **h, const char *key)
+{
+  hash_pair_t *hp = hash_get_pair_mem (*h, key);
+  if (hp)
+    {
+      void *_k = uword_to_pointer (hp->key, void *);
+      hash_unset_mem (*h, _k);
+      clib_mem_free (_k);
+    }
+}
+
+u32
+vlib_stats_create_counter (vlib_stats_entry_t *e)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  void *oldheap;
+  u32 index = ~0;
+  int i;
+
+  oldheap = clib_mem_set_heap (sm->heap);
+  vec_foreach_index_backwards (i, sm->directory_vector)
+    if (sm->directory_vector[i].type == STAT_DIR_TYPE_EMPTY)
+      {
+	index = i;
+	break;
+      }
+
+  index = index == ~0 ? vec_len (sm->directory_vector) : index;
+
+  vec_validate (sm->directory_vector, index);
+  sm->directory_vector[index] = *e;
+
+  clib_mem_set_heap (oldheap);
+  hash_set_str_key_alloc (&sm->directory_vector_by_name, e->name, index);
+
+  return index;
+}
+
+void
+vlib_stats_remove_entry (u32 entry_index)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  vlib_stats_entry_t *e = vlib_stats_get_entry (sm, entry_index);
+  void *oldheap;
+  counter_t **c;
+  u32 i;
+
+  if (entry_index >= vec_len (sm->directory_vector))
+    return;
+
+  oldheap = clib_mem_set_heap (sm->heap);
+
+  switch (e->type)
+    {
+    case STAT_DIR_TYPE_NAME_VECTOR:
+      for (i = 0; i < vec_len (e->string_vector); i++)
+	vec_free (e->string_vector[i]);
+      vec_free (e->string_vector);
+      break;
+
+    case STAT_DIR_TYPE_COUNTER_VECTOR_SIMPLE:
+      c = e->data;
+      e->data = 0;
+      for (i = 0; i < vec_len (c); i++)
+	vec_free (c[i]);
+      vec_free (c);
+      break;
+
+    case STAT_DIR_TYPE_SCALAR_INDEX:
+    case STAT_DIR_TYPE_SYMLINK:
+      break;
+    default:
+      ASSERT (0);
+    }
+
+  clib_mem_set_heap (oldheap);
+  hash_unset_str_key_free (&sm->directory_vector_by_name, e->name);
+
+  memset (e, 0, sizeof (*e));
+  e->type = STAT_DIR_TYPE_EMPTY;
+}
+
+static void
+vlib_stats_set_entry_name (vlib_stats_entry_t *e, char *s)
+{
+  u32 i, len = VLIB_STATS_MAX_NAME_SZ - 1;
+
+  for (i = 0; i < len; i++)
+    {
+      e->name[i] = s[i];
+      if (s[i] == 0)
+	return;
+    }
+  ASSERT (i < VLIB_STATS_MAX_NAME_SZ - 1);
+  s[i] = 0;
+}
+
+void
+vlib_stats_update_counter (void *cm_arg, u32 cindex,
+			   stat_directory_type_t type)
+{
+  vlib_simple_counter_main_t *cm = (vlib_simple_counter_main_t *) cm_arg;
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  vlib_stats_shared_header_t *shared_header = sm->shared_header;
+  char *stat_segment_name;
+  vlib_stats_entry_t e = { 0 };
+
+  /* Not all counters have names / hash-table entries */
+  if (!cm->name && !cm->stat_segment_name)
+    return;
+
+  ASSERT (shared_header);
+
+  vlib_stats_segment_lock ();
+
+  /* Lookup hash-table is on the main heap */
+  stat_segment_name = cm->stat_segment_name ? cm->stat_segment_name : cm->name;
+
+  u32 vector_index = vlib_stats_find_entry_index ("%s", stat_segment_name);
+
+  /* Update the vector */
+  if (vector_index == STAT_SEGMENT_INDEX_INVALID)
+    {
+      vlib_stats_set_entry_name (&e, stat_segment_name);
+      e.type = type;
+      vector_index = vlib_stats_create_counter (&e);
+    }
+
+  vlib_stats_entry_t *ep = &sm->directory_vector[vector_index];
+  ep->data = cm->counters;
+
+  /* Reset the client hash table pointer, since it WILL change! */
+  shared_header->directory_vector = sm->directory_vector;
+
+  vlib_stats_segment_unlock ();
+}
+
+void
+vlib_stats_register_error_index (u64 *em_vec, u64 index, char *fmt, ...)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  vlib_stats_shared_header_t *shared_header = sm->shared_header;
+  vlib_stats_entry_t e = {};
+  va_list va;
+  u8 *name;
+
+  va_start (va, fmt);
+  name = va_format (0, fmt, &va);
+  va_end (va);
+
+  ASSERT (shared_header);
+
+  vlib_stats_segment_lock ();
+  u32 vector_index = vlib_stats_find_entry_index ("%v", name);
+
+  if (vector_index == STAT_SEGMENT_INDEX_INVALID)
+    {
+      vec_add1 (name, 0);
+      vlib_stats_set_entry_name (&e, (char *) name);
+      e.type = STAT_DIR_TYPE_ERROR_INDEX;
+      e.index = index;
+      vector_index = vlib_stats_create_counter (&e);
+
+      /* Warn clients to refresh any pointers they might be holding */
+      shared_header->directory_vector = sm->directory_vector;
+    }
+
+  vlib_stats_segment_unlock ();
+  vec_free (name);
+}
+
+void
+vlib_stats_update_error_vector (u64 *error_vector, u32 thread_index, int lock)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  vlib_stats_shared_header_t *shared_header = sm->shared_header;
+  void *oldheap = clib_mem_set_heap (sm->heap);
+
+  ASSERT (shared_header);
+
+  if (lock)
+    vlib_stats_segment_lock ();
+
+  /* Reset the client hash table pointer, since it WILL change! */
+  vec_validate (sm->error_vector, thread_index);
+  sm->error_vector[thread_index] = error_vector;
+
+  shared_header->error_vector = sm->error_vector;
+  shared_header->directory_vector = sm->directory_vector;
+
+  if (lock)
+    vlib_stats_segment_unlock ();
+  clib_mem_set_heap (oldheap);
+}
+
+void
+vlib_stats_delete_cm (void *cm_arg)
+{
+  vlib_simple_counter_main_t *cm = (vlib_simple_counter_main_t *) cm_arg;
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  vlib_stats_entry_t *e;
+
+  /* Not all counters have names / hash-table entries */
+  if (!cm->name && !cm->stat_segment_name)
+    return;
+
+  vlib_stats_segment_lock ();
+
+  /* Lookup hash-table is on the main heap */
+  char *stat_segment_name =
+    cm->stat_segment_name ? cm->stat_segment_name : cm->name;
+  u32 index = vlib_stats_find_entry_index ("%s", stat_segment_name);
+
+  e = &sm->directory_vector[index];
+
+  hash_unset_str_key_free (&sm->directory_vector_by_name, e->name);
+
+  memset (e, 0, sizeof (*e));
+  e->type = STAT_DIR_TYPE_EMPTY;
+
+  vlib_stats_segment_unlock ();
+}
+
+static u32
+vlib_stats_new_entry_internal (stat_directory_type_t t, u8 *name)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  vlib_stats_shared_header_t *shared_header = sm->shared_header;
+  vlib_stats_entry_t e = { .type = t };
+
+  ASSERT (shared_header);
+
+  u32 vector_index = vlib_stats_find_entry_index ("%v", name);
+  if (vector_index != STAT_SEGMENT_INDEX_INVALID) /* Already registered */
+    {
+      vector_index = ~0;
+      goto done;
+    }
+
+  vec_add1 (name, 0);
+  vlib_stats_set_entry_name (&e, (char *) name);
+
+  vlib_stats_segment_lock ();
+  vector_index = vlib_stats_create_counter (&e);
+
+  shared_header->directory_vector = sm->directory_vector;
+
+  vlib_stats_segment_unlock ();
+
+done:
+  vec_free (name);
+  return vector_index;
+}
+
+u32
+vlib_stats_add_gauge (char *fmt, ...)
+{
+  va_list va;
+  u8 *name;
+
+  va_start (va, fmt);
+  name = va_format (0, fmt, &va);
+  va_end (va);
+  return vlib_stats_new_entry_internal (STAT_DIR_TYPE_SCALAR_INDEX, name);
+}
+
+void
+vlib_stats_set_gauge (u32 index, u64 value)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+
+  ASSERT (index < vec_len (sm->directory_vector));
+  sm->directory_vector[index].value = value;
+}
+
+u32
+vlib_stats_add_timestamp (char *fmt, ...)
+{
+  va_list va;
+  u8 *name;
+
+  va_start (va, fmt);
+  name = va_format (0, fmt, &va);
+  va_end (va);
+  return vlib_stats_new_entry_internal (STAT_DIR_TYPE_SCALAR_INDEX, name);
+}
+
+void
+vlib_stats_set_timestamp (u32 entry_index, f64 value)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+
+  ASSERT (entry_index < vec_len (sm->directory_vector));
+  sm->directory_vector[entry_index].value = value;
+}
+
+u32
+vlib_stats_add_string_vector (char *fmt, ...)
+{
+  va_list va;
+  u8 *name;
+
+  va_start (va, fmt);
+  name = va_format (0, fmt, &va);
+  va_end (va);
+  return vlib_stats_new_entry_internal (STAT_DIR_TYPE_NAME_VECTOR, name);
+}
+
+void
+vlib_stats_set_string_vector (u32 entry_index, u32 vector_index, char *fmt,
+			      ...)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  vlib_stats_entry_t *e = vlib_stats_get_entry (sm, entry_index);
+  va_list va;
+  void *oldheap;
+
+  oldheap = clib_mem_set_heap (sm->heap);
+  vlib_stats_segment_lock ();
+
+  vec_validate (e->string_vector, vector_index);
+  vec_reset_length (e->string_vector[vector_index]);
+
+  va_start (va, fmt);
+  e->string_vector[vector_index] =
+    va_format (e->string_vector[vector_index], fmt, &va);
+  va_end (va);
+
+  vlib_stats_segment_unlock ();
+  clib_mem_set_heap (oldheap);
+}
+
+u32
+vlib_stats_add_counter_vector (char *fmt, ...)
+{
+  va_list va;
+  u8 *name;
+
+  va_start (va, fmt);
+  name = va_format (0, fmt, &va);
+  va_end (va);
+  return vlib_stats_new_entry_internal (STAT_DIR_TYPE_COUNTER_VECTOR_SIMPLE,
+					name);
+}
+
+void
+vlib_stats_validate_counter_vector (u32 entry_index, u32 vector_index)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  vlib_stats_entry_t *e = vlib_stats_get_entry (sm, entry_index);
+  void *oldheap;
+  counter_t **c = e->data;
+
+  if (vec_len (c) > 0 && vec_len (c[0]) > vector_index)
+    return;
+
+  oldheap = clib_mem_set_heap (sm->heap);
+  vlib_stats_segment_lock ();
+
+  vec_validate_aligned (c, 0, CLIB_CACHE_LINE_BYTES);
+  vec_validate_aligned (c[0], vector_index, CLIB_CACHE_LINE_BYTES);
+  e->data = c;
+
+  vlib_stats_segment_unlock ();
+  clib_mem_set_heap (oldheap);
+}
+
+u32
+vlib_stats_add_symlink (u32 entry_index, u32 vector_index, char *fmt, ...)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  vlib_stats_shared_header_t *shared_header = sm->shared_header;
+  vlib_stats_entry_t e;
+  va_list va;
+  u8 *name;
+
+  ASSERT (shared_header);
+  ASSERT (entry_index < vec_len (sm->directory_vector));
+
+  va_start (va, fmt);
+  name = va_format (0, fmt, &va);
+  va_end (va);
+
+  if (vlib_stats_find_entry_index ("%v", name) == STAT_SEGMENT_INDEX_INVALID)
+    {
+      vec_add1 (name, 0);
+      vlib_stats_set_entry_name (&e, (char *) name);
+      e.type = STAT_DIR_TYPE_SYMLINK;
+      e.index1 = entry_index;
+      e.index2 = vector_index;
+      vector_index = vlib_stats_create_counter (&e);
+
+      /* Warn clients to refresh any pointers they might be holding */
+      shared_header->directory_vector = sm->directory_vector;
+    }
+  else
+    vector_index = ~0;
+
+  vec_free (name);
+  return vector_index;
+}
+
+void
+vlib_stats_rename_symlink (u64 entry_index, char *fmt, ...)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  vlib_stats_entry_t *e = vlib_stats_get_entry (sm, entry_index);
+  va_list va;
+  u8 *new_name;
+
+  hash_unset_str_key_free (&sm->directory_vector_by_name, e->name);
+
+  va_start (va, fmt);
+  new_name = va_format (0, fmt, &va);
+  va_end (va);
+
+  vec_add1 (new_name, 0);
+  vlib_stats_set_entry_name (e, (char *) new_name);
+  hash_set_str_key_alloc (&sm->directory_vector_by_name, e->name, entry_index);
+  vec_free (new_name);
+}
+
+f64
+vlib_stats_get_segment_update_rate (void)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  return sm->update_interval;
+}
+
+void
+vlib_stats_register_collector_fn (vlib_stats_collector_reg_t *reg)
+{
+  vlib_stats_segment_t *sm = vlib_stats_get_segment ();
+  vlib_stats_collector_t *c;
+
+  ASSERT (reg->entry_index != ~0);
+
+  pool_get_zero (sm->collectors, c);
+  c->fn = reg->collect_fn;
+  c->entry_index = reg->entry_index;
+  c->vector_index = reg->vector_index;
+  c->private_data = reg->private_data;
+
+  return;
+}
diff --git a/src/vlib/stats/stats.h b/src/vlib/stats/stats.h
new file mode 100644
index 00000000000..25d7c4ba484
--- /dev/null
+++ b/src/vlib/stats/stats.h
@@ -0,0 +1,160 @@
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright(c) 2022 Cisco Systems, Inc.
+ */
+
+#ifndef included_stats_stats_h
+#define included_stats_stats_h
+
+#include <vppinfra/socket.h>
+#include <vppinfra/lock.h>
+#include <vlib/stats/shared.h>
+
+/* Default stat segment 32m */
+#define STAT_SEGMENT_DEFAULT_SIZE (32 << 20)
+
+/* Shared segment memory layout version */
+#define STAT_SEGMENT_VERSION 2
+
+#define STAT_SEGMENT_INDEX_INVALID UINT32_MAX
+
+typedef enum
+{
+  STAT_COUNTER_HEARTBEAT = 0,
+  STAT_COUNTER_LAST_STATS_CLEAR,
+  STAT_COUNTER_NODE_CLOCKS,
+  STAT_COUNTER_NODE_VECTORS,
+  STAT_COUNTER_NODE_CALLS,
+  STAT_COUNTER_NODE_SUSPENDS,
+  STAT_COUNTER_NODE_NAMES,
+  STAT_COUNTERS
+} stat_segment_counter_t;
+
+#define foreach_stat_segment_node_counter_name                                \
+  _ (NODE_CLOCKS, COUNTER_VECTOR_SIMPLE, clocks, "/sys/node")                 \
+  _ (NODE_VECTORS, COUNTER_VECTOR_SIMPLE, vectors, "/sys/node")               \
+  _ (NODE_CALLS, COUNTER_VECTOR_SIMPLE, calls, "/sys/node")                   \
+  _ (NODE_SUSPENDS, COUNTER_VECTOR_SIMPLE, suspends, "/sys/node")
+
+#define foreach_stat_segment_counter_name                                     \
+  _ (LAST_STATS_CLEAR, SCALAR_INDEX, last_stats_clear, "/sys")                \
+  _ (HEARTBEAT, SCALAR_INDEX, heartbeat, "/sys")                              \
+  _ (NODE_NAMES, NAME_VECTOR, names, "/sys/node")                             \
+  foreach_stat_segment_node_counter_name
+
+typedef struct
+{
+  u32 entry_index;
+  u32 vector_index;
+  u64 private_data;
+  vlib_stats_entry_t *entry;
+} vlib_stats_collector_data_t;
+
+typedef void (*vlib_stats_collector_fn_t) (vlib_stats_collector_data_t *);
+
+typedef struct
+{
+  vlib_stats_collector_fn_t collect_fn;
+  u32 entry_index;
+  u32 vector_index;
+  u64 private_data;
+} vlib_stats_collector_reg_t;
+
+typedef struct
+{
+  vlib_stats_collector_fn_t fn;
+  u32 entry_index;
+  u32 vector_index;
+  u64 private_data;
+} vlib_stats_collector_t;
+
+typedef struct
+{
+  /* internal, does not point to shared memory */
+  vlib_stats_collector_t *collectors;
+
+  /* statistics segment */
+  uword *directory_vector_by_name;
+  vlib_stats_entry_t *directory_vector;
+  volatile u64 **error_vector;
+  u8 **nodes;
+
+  /* Update interval */
+  f64 update_interval;
+
+  clib_spinlock_t *stat_segment_lockp;
+  clib_socket_t *socket;
+  u8 *socket_name;
+  ssize_t memory_size;
+  clib_mem_page_sz_t log2_page_sz;
+  u8 node_counters_enabled;
+  void *heap;
+  vlib_stats_shared_header_t
+    *shared_header; /* pointer to shared memory segment */
+  int memfd;
+
+} vlib_stats_segment_t;
+
+typedef struct
+{
+  vlib_stats_segment_t segment;
+} vlib_stats_main_t;
+
+extern vlib_stats_main_t vlib_stats_main;
+
+static_always_inline vlib_stats_segment_t *
+vlib_stats_get_segment ()
+{
+  return &vlib_stats_main.segment;
+}
+
+static_always_inline vlib_stats_entry_t *
+vlib_stats_get_entry (vlib_stats_segment_t *sm, u32 entry_index)
+{
+  vlib_stats_entry_t *e;
+  ASSERT (entry_index < vec_len (sm->directory_vector));
+  e = sm->directory_vector + entry_index;
+  ASSERT (e->type != STAT_DIR_TYPE_EMPTY && e->type != STAT_DIR_TYPE_ILLEGAL);
+  return e;
+}
+
+clib_error_t *vlib_stats_init (vlib_main_t *vm);
+void *vlib_stats_set_heap ();
+void vlib_stats_update_counter (void *, u32, stat_directory_type_t);
+void vlib_stats_register_error_index (u64 *em_vec, u64 index, char *fmt, ...);
+void vlib_stats_update_error_vector (u64 *error_vector, u32 thread_index,
+				     int lock);
+void vlib_stats_segment_lock (void);
+void vlib_stats_segment_unlock (void);
+void vlib_stats_delete_cm (void *);
+void vlib_stats_register_mem_heap (clib_mem_heap_t *);
+f64 vlib_stats_get_segment_update_rate (void);
+
+/* gauge */
+u32 vlib_stats_add_gauge (char *fmt, ...);
+void vlib_stats_set_gauge (u32 entry_index, u64 value);
+
+/* timestamp */
+u32 vlib_stats_add_timestamp (char *fmt, ...);
+void vlib_stats_set_timestamp (u32 entry_index, f64 value);
+
+/* vector */
+u32 vlib_stats_add_counter_vector (char *fmt, ...);
+void vlib_stats_validate_counter_vector (u32 entry_index, u32 vector_index);
+
+/* string vector */
+u32 vlib_stats_add_string_vector (char *fmt, ...);
+void vlib_stats_set_string_vector (u32 entry_index, u32 vector_index,
+				   char *fmt, ...);
+
+/* symlink */
+u32 vlib_stats_add_symlink (u32 entry_index, u32 vector_index, char *fmt, ...);
+void vlib_stats_rename_symlink (u64 entry_index, char *fmt, ...);
+
+/* common to all types */
+void vlib_stats_remove_entry (u32 entry_index);
+u32 vlib_stats_find_entry_index (char *fmt, ...);
+void vlib_stats_register_collector_fn (vlib_stats_collector_reg_t *r);
+
+format_function_t format_vlib_stats_symlink;
+
+#endif