Add tracer for pending tags

4 files changed, 38 insertions, 1 deletions

diff --git a/src/core/lib/iomgr/error.h b/src/core/lib/iomgr/error.h
index e02b12f2f4..bc7781250e 100644
--- a/src/core/lib/iomgr/error.h
+++ b/src/core/lib/iomgr/error.h
@@ -148,7 +148,7 @@ grpc_error *grpc_error_create(const char *file, int line, const char *desc,
 #define GRPC_ERROR_CREATE_REFERENCING(desc, errs, count) \
   grpc_error_create(__FILE__, __LINE__, desc, errs, count)
 
-#define GRPC_ERROR_REFCOUNT_DEBUG
+//#define GRPC_ERROR_REFCOUNT_DEBUG
 #ifdef GRPC_ERROR_REFCOUNT_DEBUG
 grpc_error *grpc_error_ref(grpc_error *err, const char *file, int line,
                            const char *func);
diff --git a/src/core/lib/surface/completion_queue.c b/src/core/lib/surface/completion_queue.c
index 2412f78a06..5654b86d8b 100644
--- a/src/core/lib/surface/completion_queue.c
+++ b/src/core/lib/surface/completion_queue.c
@@ -39,6 +39,7 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/atm.h>
 #include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
 #include <grpc/support/time.h>
 
 #include "src/core/lib/iomgr/pollset.h"
@@ -50,6 +51,9 @@
 #include "src/core/lib/surface/event_string.h"
 
 int grpc_trace_operation_failures;
+#ifndef NDEBUG
+int grpc_trace_pending_tags;
+#endif
 
 typedef struct {
   grpc_pollset_worker **worker;
@@ -338,6 +342,25 @@ static bool cq_is_next_finished(grpc_exec_ctx *exec_ctx, void *arg) {
   return gpr_time_cmp(a->deadline, gpr_now(a->deadline.clock_type)) < 0;
 }
 
+#ifndef NDEBUG
+static void dump_pending_tags(grpc_completion_queue *cc) {
+  if (!grpc_trace_pending_tags) return;
+
+  gpr_strvec v;
+  gpr_strvec_init(&v);
+  gpr_strvec_add(&v, gpr_strdup("PENDING TAGS:"));
+  for (size_t i = 0; i < cc->outstanding_tag_count; i++) {
+    char *s;
+    gpr_asprintf(&s, " %p", cc->outstanding_tags[i]);
+    gpr_strvec_add(&v, s);
+  }
+  char *out = gpr_strvec_flatten(&v, NULL);
+  gpr_strvec_destroy(&v);
+  gpr_log(GPR_DEBUG, "%s", out);
+  gpr_free(out);
+}
+#endif
+
 grpc_event grpc_completion_queue_next(grpc_completion_queue *cc,
                                       gpr_timespec deadline, void *reserved) {
   grpc_event ret;
@@ -357,6 +380,10 @@ grpc_event grpc_completion_queue_next(grpc_completion_queue *cc,
           reserved));
   GPR_ASSERT(!reserved);
 
+#ifndef NDEBUG
+  dump_pending_tags(cc);
+#endif
+
   deadline = gpr_convert_clock_type(deadline, GPR_CLOCK_MONOTONIC);
 
   cq_is_finished_arg is_finished_arg = {cc, deadline, NULL, NULL};
@@ -510,6 +537,10 @@ grpc_event grpc_completion_queue_pluck(grpc_completion_queue *cc, void *tag,
   }
   GPR_ASSERT(!reserved);
 
+#ifndef NDEBUG
+  dump_pending_tags(cc);
+#endif
+
   deadline = gpr_convert_clock_type(deadline, GPR_CLOCK_MONOTONIC);
 
   cq_is_finished_arg is_finished_arg = {cc, deadline, NULL, tag};
diff --git a/src/core/lib/surface/completion_queue.h b/src/core/lib/surface/completion_queue.h
index 3049284f68..e9d840df77 100644
--- a/src/core/lib/surface/completion_queue.h
+++ b/src/core/lib/surface/completion_queue.h
@@ -44,6 +44,9 @@
 extern int grpc_cq_pluck_trace;
 extern int grpc_cq_event_timeout_trace;
 extern int grpc_trace_operation_failures;
+#ifndef NDEBUG
+extern int grpc_trace_pending_tags;
+#endif
 
 typedef struct grpc_cq_completion {
   /** user supplied tag */
diff --git a/src/core/lib/surface/init.c b/src/core/lib/surface/init.c
index edda0c85fa..ac111253ef 100644
--- a/src/core/lib/surface/init.c
+++ b/src/core/lib/surface/init.c
@@ -173,6 +173,9 @@ void grpc_init(void) {
     // Default timeout trace to 1
     grpc_cq_event_timeout_trace = 1;
     grpc_register_tracer("op_failure", &grpc_trace_operation_failures);
+#ifndef NDEBUG
+    grpc_register_tracer("pending_tags", &grpc_trace_pending_tags);
+#endif
     grpc_security_pre_init();
     grpc_iomgr_init();
     grpc_executor_init();