STATS: Dynamically mapped shared memory segment

Move from using a hash to a vector with offsets into shared memory.
Limit exposure of VPP data structures and include files to
external stats library and applications.

Change-Id: Ic06129f12d10cf4c4946a86d9bc734eacff2c7da
Signed-off-by: Ole Troan <ot@cisco.com>

1 files changed, 97 insertions, 0 deletions

diff --git a/src/vpp/stats/stat_segment.h b/src/vpp/stats/stat_segment.h
new file mode 100644
index 00000000000..0efd45ac5f0
--- /dev/null
+++ b/src/vpp/stats/stat_segment.h
@@ -0,0 +1,97 @@
+/*
+ * Copyright (c) 2018 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_stat_segment_h
+#define included_stat_segment_h
+
+#include <stdatomic.h>
+
+/* Default socket to exchange segment fd */
+#define STAT_SEGMENT_SOCKET_FILE "/run/vpp/stats.sock"
+
+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_directory_type_t;
+
+typedef enum
+{
+ STAT_COUNTER_VECTOR_RATE = 0,
+ STAT_COUNTER_INPUT_RATE,
+ STAT_COUNTER_LAST_UPDATE,
+ STAT_COUNTER_LAST_STATS_CLEAR,
+ STAT_COUNTER_HEARTBEAT,
+ STAT_COUNTER_NODE_CLOCKS,
+ STAT_COUNTER_NODE_VECTORS,
+ STAT_COUNTER_NODE_CALLS,
+ STAT_COUNTER_NODE_SUSPENDS,
+ STAT_COUNTERS
+} stat_segment_counter_t;
+
+#define foreach_stat_segment_counter_name			\
+  _(VECTOR_RATE, SCALAR_INDEX, vector_rate,)			\
+  _(INPUT_RATE, SCALAR_INDEX, input_rate,)			\
+  _(LAST_UPDATE, SCALAR_INDEX, last_update,)			\
+  _(LAST_STATS_CLEAR, SCALAR_INDEX, last_stats_clear,)		\
+  _(HEARTBEAT, SCALAR_INDEX, heartbeat,)			\
+  _(NODE_CLOCKS, COUNTER_VECTOR_SIMPLE, clocks, /node)		\
+  _(NODE_VECTORS, COUNTER_VECTOR_SIMPLE, vectors, /node)	\
+  _(NODE_CALLS, COUNTER_VECTOR_SIMPLE, calls, /node)		\
+  _(NODE_SUSPENDS, COUNTER_VECTOR_SIMPLE, suspends, /node)
+
+typedef struct
+{
+  stat_directory_type_t type;
+  union {
+    uint64_t offset;
+    uint64_t index;
+    uint64_t value;
+  };
+  uint64_t offset_vector;
+  char name[128]; // TODO change this to pointer to "somewhere"
+} stat_segment_directory_entry_t;
+
+/* Default stat segment 32m */
+#define STAT_SEGMENT_DEFAULT_SIZE	(32<<20)
+
+/*
+ * Shared header first in the shared memory segment.
+ */
+typedef struct
+{
+  atomic_int_fast64_t epoch;
+  atomic_int_fast64_t in_progress;
+  atomic_int_fast64_t directory_offset;
+  atomic_int_fast64_t error_offset;
+  atomic_int_fast64_t stats_offset;
+} stat_segment_shared_header_t;
+
+static inline uint64_t
+stat_segment_offset (void *start, void *data)
+{
+  return (char *) data - (char *) start;
+}
+
+static inline void *
+stat_segment_pointer (void *start, uint64_t offset)
+{
+  return ((char *) start + offset);
+}
+
+#endif