clang: Add annotations for thread safety check.

[sliver-openvswitch.git] / lib / vlog.h

diff --git a/lib/vlog.h b/lib/vlog.h
index ab746c8..901b3d3 100644 (file)
--- a/lib/vlog.h
+++ b/lib/vlog.h
@@ -17,11 +17,21 @@
 #ifndef VLOG_H
 #define VLOG_H 1
 
+/* Logging.
+ *
+ *
+ * Thread-safety
+ * =============
+ *
+ * Fully thread safe.
+ */
+
 #include <limits.h>
 #include <stdarg.h>
 #include <stdbool.h>
 #include <time.h>
 #include "compiler.h"
+#include "ovs-thread.h"
 #include "sat-math.h"
 #include "token-bucket.h"
 #include "util.h"
@@ -52,7 +62,7 @@ enum vlog_level vlog_get_level_val(const char *name);
 
 /* Facilities that we can log to. */
 #define VLOG_FACILITIES                                                 \
-    VLOG_FACILITY(SYSLOG, "%05N|%c%T|%p|%m")                            \
+    VLOG_FACILITY(SYSLOG, "ovs|%05N|%c%T|%p|%m")                            \
     VLOG_FACILITY(CONSOLE, "%D{%Y-%m-%dT%H:%M:%SZ}|%05N|%c%T|%p|%m")    \
     VLOG_FACILITY(FILE, "%D{%Y-%m-%dT%H:%M:%SZ}|%05N|%c%T|%p|%m")
 enum vlog_facility {
@@ -78,8 +88,8 @@ struct vlog_module {
 #if USE_LINKER_SECTIONS
 #define VLOG_DEFINE_MODULE(MODULE)                                      \
         VLOG_DEFINE_MODULE__(MODULE)                                    \
-        extern struct vlog_module *vlog_module_ptr_##MODULE;            \
-        struct vlog_module *vlog_module_ptr_##MODULE                    \
+        extern struct vlog_module *const vlog_module_ptr_##MODULE;      \
+        struct vlog_module *const vlog_module_ptr_##MODULE              \
             __attribute__((section("vlog_modules"))) = &VLM_##MODULE
 #else
 #define VLOG_DEFINE_MODULE(MODULE) extern struct vlog_module VLM_##MODULE
@@ -94,6 +104,7 @@ struct vlog_rate_limit {
     time_t first_dropped;       /* Time first message was dropped. */
     time_t last_dropped;        /* Time of most recent message drop. */
     unsigned int n_dropped;     /* Number of messages dropped. */
+    struct ovs_mutex mutex;     /* Mutual exclusion for rate limit. */
 };
 
 /* Number of tokens to emit a message.  We add 'rate' tokens per millisecond,
@@ -108,6 +119,7 @@ struct vlog_rate_limit {
             0,                              /* first_dropped */         \
             0,                              /* last_dropped */          \
             0,                              /* n_dropped */             \
+            OVS_ADAPTIVE_MUTEX_INITIALIZER  /* mutex */                 \
         }
 
 /* Configuring how each module logs messages. */
@@ -124,13 +136,11 @@ void vlog_set_verbosity(const char *arg);
 
 /* Configuring log facilities. */
 void vlog_set_pattern(enum vlog_facility, const char *pattern);
-const char *vlog_get_log_file(void);
 int vlog_set_log_file(const char *file_name);
 int vlog_reopen_log_file(void);
 
 /* Initialization. */
 void vlog_init(void);
-void vlog_exit(void);
 
 /* Functions for actual logging. */
 void vlog(const struct vlog_module *, enum vlog_level, const char *format, ...)
@@ -230,13 +240,13 @@ void vlog_usage(void);
             vlog_rate_limit(THIS_MODULE, level__, RL, __VA_ARGS__); \
         }                                                           \
     } while (0)
-#define VLOG_ONCE(LEVEL, ...)                       \
-    do {                                            \
-        static bool already_logged;                 \
-        if (!already_logged) {                      \
-            already_logged = true;                  \
-            vlog(THIS_MODULE, LEVEL, __VA_ARGS__);  \
-        }                                           \
+#define VLOG_ONCE(LEVEL, ...)                                           \
+    do {                                                                \
+        static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER; \
+        if (ovsthread_once_start(&once)) {                              \
+            vlog(THIS_MODULE, LEVEL, __VA_ARGS__);                      \
+            ovsthread_once_done(&once);                                 \
+        }                                                               \
     } while (0)
 
 #define VLOG_DEFINE_MODULE__(MODULE)                                    \