stats: refactor header files

Performant stat segment scraping involves caching the results of
stat_segment_ls (...) and directly fishing counter data from the
shared-memory segment.

To do that, we need to publish several things previously hidden,
declared in stat_client.c:

o stat_client_main_t typedef
o stat_segment_access_t typedef
o stat_segment_access_start inline function
o stat_segment_access_end inline function

Type: refactor

Signed-off-by: Dave Barach <dave@barachs.net>
Change-Id: I3175e3d1f1fd8ea816336a584565179d1972115c

1 files changed, 41 insertions, 12 deletions

diff --git a/src/vpp-api/client/stat_client.h b/src/vpp-api/client/stat_client.h
index 10b54c8d601..97a21dd0004 100644
--- a/src/vpp-api/client/stat_client.h
+++ b/src/vpp-api/client/stat_client.h
@@ -23,24 +23,14 @@
 #include <stdint.h>
 #include <unistd.h>
 #include <vlib/counter_types.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_directory_type_t;
+#include <stdbool.h>
+#include <vpp/stats/stat_segment_shared.h>
 
 /* Default socket to exchange segment fd */
 /* TODO: Get from runtime directory */
 #define STAT_SEGMENT_SOCKET_FILE "/run/vpp/stats.sock"
 #define STAT_SEGMENT_SOCKET_FILENAME "stats.sock"
 
-typedef struct stat_client_main_t stat_client_main_t;
-
 typedef struct
 {
   char *name;
@@ -55,6 +45,16 @@ typedef struct
   };
 } stat_segment_data_t;
 
+typedef struct
+{
+  uint64_t current_epoch;
+  stat_segment_shared_header_t *shared_header;
+  stat_segment_directory_entry_t *directory_vector;
+  ssize_t memory_size;
+} stat_client_main_t;
+
+extern stat_client_main_t stat_client_main;
+
 stat_client_main_t *stat_client_get (void);
 void stat_client_free (stat_client_main_t * sm);
 int stat_segment_connect_r (const char *socket_name, stat_client_main_t * sm);
@@ -83,6 +83,35 @@ char *stat_segment_index_to_name (uint32_t index);
 uint64_t stat_segment_version (void);
 uint64_t stat_segment_version_r (stat_client_main_t * sm);
 
+typedef struct
+{
+  uint64_t epoch;
+} stat_segment_access_t;
+
+static inline void
+stat_segment_access_start (stat_segment_access_t * sa,
+			   stat_client_main_t * sm)
+{
+  stat_segment_shared_header_t *shared_header = sm->shared_header;
+  sa->epoch = shared_header->epoch;
+  while (shared_header->in_progress != 0)
+    ;
+  sm->directory_vector = (stat_segment_directory_entry_t *)
+    stat_segment_pointer (sm->shared_header,
+			  sm->shared_header->directory_offset);
+}
+
+static inline bool
+stat_segment_access_end (stat_segment_access_t * sa, stat_client_main_t * sm)
+{
+  stat_segment_shared_header_t *shared_header = sm->shared_header;
+
+  if (shared_header->epoch != sa->epoch || shared_header->in_progress)
+    return false;
+  return true;
+}
+
+
 #endif /* included_stat_client_h */
 
 /*