Merge branch 'master' into cq_mpsc_based

2 files changed, 40 insertions, 7 deletions

diff --git a/src/core/lib/debug/trace.c b/src/core/lib/debug/trace.c
index c56046785b..4dfea44c57 100644
--- a/src/core/lib/debug/trace.c
+++ b/src/core/lib/debug/trace.c
@@ -35,24 +35,31 @@
 
 #include <string.h>
 
-#include <grpc/grpc.h>
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 #include "src/core/lib/support/env.h"
 
+int grpc_tracer_set_enabled(const char *name, int enabled);
+
 typedef struct tracer {
   const char *name;
-  int *flag;
+  grpc_tracer_flag *flag;
   struct tracer *next;
 } tracer;
 static tracer *tracers;
 
-void grpc_register_tracer(const char *name, int *flag) {
+#ifdef GRPC_THREADSAFE_TRACER
+#define TRACER_SET(flag, on) gpr_atm_no_barrier_store(&(flag).value, (on))
+#else
+#define TRACER_SET(flag, on) (flag).value = (on)
+#endif
+
+void grpc_register_tracer(const char *name, grpc_tracer_flag *flag) {
   tracer *t = gpr_malloc(sizeof(*t));
   t->name = name;
   t->flag = flag;
   t->next = tracers;
-  *flag = 0;
+  TRACER_SET(*flag, false);
   tracers = t;
 }
 
@@ -121,13 +128,13 @@ int grpc_tracer_set_enabled(const char *name, int enabled) {
   tracer *t;
   if (0 == strcmp(name, "all")) {
     for (t = tracers; t; t = t->next) {
-      *t->flag = enabled;
+      TRACER_SET(*t->flag, enabled);
     }
   } else {
     int found = 0;
     for (t = tracers; t; t = t->next) {
       if (0 == strcmp(name, t->name)) {
-        *t->flag = enabled;
+        TRACER_SET(*t->flag, enabled);
         found = 1;
       }
     }
diff --git a/src/core/lib/debug/trace.h b/src/core/lib/debug/trace.h
index 7afc38db7e..ba432574d0 100644
--- a/src/core/lib/debug/trace.h
+++ b/src/core/lib/debug/trace.h
@@ -34,9 +34,35 @@
 #ifndef GRPC_CORE_LIB_DEBUG_TRACE_H
 #define GRPC_CORE_LIB_DEBUG_TRACE_H
 
+#include <grpc/support/atm.h>
 #include <grpc/support/port_platform.h>
+#include <stdbool.h>
 
-void grpc_register_tracer(const char *name, int *flag);
+#if defined(__has_feature)
+#if __has_feature(thread_sanitizer)
+#define GRPC_THREADSAFE_TRACER
+#endif
+#endif
+
+typedef struct {
+#ifdef GRPC_THREADSAFE_TRACER
+  gpr_atm value;
+#else
+  bool value;
+#endif
+} grpc_tracer_flag;
+
+#ifdef GRPC_THREADSAFE_TRACER
+#define GRPC_TRACER_ON(flag) (gpr_atm_no_barrier_load(&(flag).value) != 0)
+#define GRPC_TRACER_INITIALIZER(on) \
+  { (gpr_atm)(on) }
+#else
+#define GRPC_TRACER_ON(flag) ((flag).value)
+#define GRPC_TRACER_INITIALIZER(on) \
+  { (on) }
+#endif
+
+void grpc_register_tracer(const char *name, grpc_tracer_flag *flag);
 void grpc_tracer_init(const char *env_var_name);
 void grpc_tracer_shutdown(void);