handle uninitialized buffer during profile peek

Author: IanButterworth

src/signal-handling.c

@@ -29,6 +29,52 @@ static const    uint64_t GIGA = 1000000000ULL;
 JL_DLLEXPORT void jl_profile_stop_timer(void);
 JL_DLLEXPORT int jl_profile_start_timer(void);
 
+///////////////////////
+// Utility functions //
+///////////////////////
+JL_DLLEXPORT int jl_profile_init(size_t maxsize, uint64_t delay_nsec)
+{
+    bt_size_max = maxsize;
+    nsecprof = delay_nsec;
+    if (bt_data_prof != NULL)
+        free((void*)bt_data_prof);
+    bt_data_prof = (jl_bt_element_t*) calloc(maxsize, sizeof(jl_bt_element_t));
+    if (bt_data_prof == NULL && maxsize > 0)
+        return -1;
+    bt_size_cur = 0;
+    return 0;
+}
+
+JL_DLLEXPORT uint8_t *jl_profile_get_data(void)
+{
+    return (uint8_t*) bt_data_prof;
+}
+
+JL_DLLEXPORT size_t jl_profile_len_data(void)
+{
+    return bt_size_cur;
+}
+
+JL_DLLEXPORT size_t jl_profile_maxlen_data(void)
+{
+    return bt_size_max;
+}
+
+JL_DLLEXPORT uint64_t jl_profile_delay_nsec(void)
+{
+    return nsecprof;
+}
+
+JL_DLLEXPORT void jl_profile_clear_data(void)
+{
+    bt_size_cur = 0;
+}
+
+JL_DLLEXPORT int jl_profile_is_running(void)
+{
+    return running;
+}
+
 // Any function that acquires this lock must be either a unmanaged thread
 // or in the GC safe region and must NOT allocate anything through the GC
 // while holding this lock.
@@ -426,52 +472,6 @@ void jl_critical_error(int sig, bt_context_t *context, jl_task_t *ct)
     jl_gc_debug_critical_error();
 }
 
-///////////////////////
-// Utility functions //
-///////////////////////
-JL_DLLEXPORT int jl_profile_init(size_t maxsize, uint64_t delay_nsec)
-{
-    bt_size_max = maxsize;
-    nsecprof = delay_nsec;
-    if (bt_data_prof != NULL)
-        free((void*)bt_data_prof);
-    bt_data_prof = (jl_bt_element_t*) calloc(maxsize, sizeof(jl_bt_element_t));
-    if (bt_data_prof == NULL && maxsize > 0)
-        return -1;
-    bt_size_cur = 0;
-    return 0;
-}
-
-JL_DLLEXPORT uint8_t *jl_profile_get_data(void)
-{
-    return (uint8_t*) bt_data_prof;
-}
-
-JL_DLLEXPORT size_t jl_profile_len_data(void)
-{
-    return bt_size_cur;
-}
-
-JL_DLLEXPORT size_t jl_profile_maxlen_data(void)
-{
-    return bt_size_max;
-}
-
-JL_DLLEXPORT uint64_t jl_profile_delay_nsec(void)
-{
-    return nsecprof;
-}
-
-JL_DLLEXPORT void jl_profile_clear_data(void)
-{
-    bt_size_cur = 0;
-}
-
-JL_DLLEXPORT int jl_profile_is_running(void)
-{
-    return running;
-}
-
 #ifdef __cplusplus
 }
 #endif

src/signals-unix.c

@@ -698,6 +698,14 @@ void trigger_profile_peek(void)
     jl_safe_printf("\n======================================================================================\n");
     jl_safe_printf("Information request received. A stacktrace will print followed by a %.1f second profile\n", profile_peek_duration);
     jl_safe_printf("======================================================================================\n");
+    if (bt_size_max == 0){
+        // If the buffer hasn't been initialized, initialize with default size
+        // Keep these values synchronized with Profile.default_init()
+        if (jl_profile_init(10000000 * jl_n_threads, 1000000) == -1){
+            jl_safe_printf("ERROR: could not initialize the profile buffer");
+            return;
+        }
+    }
     bt_size_cur = 0; // clear profile buffer
     if (jl_profile_start_timer() < 0)
         jl_safe_printf("ERROR: Could not start profile timer\n");

stdlib/Profile/src/Profile.jl

@@ -138,6 +138,7 @@ function default_init()
         n = 1_000_000
         delay = 0.01
     else
+        # Keep these values synchronized with trigger_profile_peek
         n = 10_000_000
         delay = 0.001
     end