Log MI of every CI that was GCed

Author: d-netto

src/array.c

@@ -457,43 +457,13 @@ JL_DLLEXPORT jl_array_t *jl_pchar_to_array(const char *str, size_t len)
     return a;
 }
 
-uv_mutex_t array_to_string_print_lock;
-
-void jl_set_in_flight_bit_for_array_to_string(jl_array_t *a)
-{
-    uintptr_t msk = (1 << ARRAY_TO_STRING_IN_FLIGHT_BIT_OFFSET);
-    uintptr_t header = jl_atomic_fetch_or((_Atomic(uintptr_t) *)jl_astaggedvalue(a), msk);
-    if (header & msk) {
-        uv_mutex_lock(&array_to_string_print_lock);
-        // Race detected... Someone already set the in-flight bit.
-        jl_safe_printf("Race detected... Someone already set the in-flight bit.\n");
-        jlbacktracet(jl_current_task);
-        uv_mutex_unlock(&array_to_string_print_lock);
-    }
-}
-
-void jl_reset_in_flight_bit_for_array_to_string(jl_array_t *a)
-{
-    uintptr_t msk = (1 << ARRAY_TO_STRING_IN_FLIGHT_BIT_OFFSET);
-    uintptr_t header = jl_atomic_fetch_and((_Atomic(uintptr_t) *)jl_astaggedvalue(a), ~msk);
-    if (!(header & msk)) {
-        uv_mutex_lock(&array_to_string_print_lock);
-        // Race detected... Someone reset the in-flight bit before we could.
-        jl_safe_printf("Race detected... Someone reset the in-flight bit before we could.\n");
-        jlbacktracet(jl_current_task);
-        uv_mutex_unlock(&array_to_string_print_lock);
-    }
-}
-
 JL_DLLEXPORT jl_value_t *jl_array_to_string(jl_array_t *a)
 {
-    jl_set_in_flight_bit_for_array_to_string(a);
     size_t len = jl_array_len(a);
     if (len == 0) {
         // this may seem like purely an optimization (which it also is), but it
         // also ensures that calling `String(a)` doesn't corrupt a previous
         // string also created the same way, where `a = StringVector(_)`.
-        jl_reset_in_flight_bit_for_array_to_string(a);
         return jl_an_empty_string;
     }
     if (a->flags.how == 3 && a->offset == 0 && a->elsize == 1 &&
@@ -506,13 +476,11 @@ JL_DLLEXPORT jl_value_t *jl_array_to_string(jl_array_t *a)
             a->nrows = 0;
             a->length = 0;
             a->maxsize = 0;
-            jl_reset_in_flight_bit_for_array_to_string(a);
             return o;
         }
     }
     a->nrows = 0;
     a->length = 0;
-    jl_reset_in_flight_bit_for_array_to_string(a);
     return jl_pchar_to_string((const char*)jl_array_data(a), len);
 }
 

src/gc.c

@@ -1472,6 +1472,20 @@ static void gc_sweep_page(gc_page_profiler_serializer_t *s, jl_gc_pool_t *p, jl_
             int bits = v->bits.gc;
             // if an object is past `lim_newpages` then we can guarantee it's garbage
             if (!gc_marked(bits) || (char*)v >= lim_newpages) {
+                if (jl_is_method_instance(jl_valueof(v)) || jl_is_method(jl_valueof(v))) {
+                    if (!v->bits.obj_whose_gc_was_delayed) {
+                        v->bits.obj_whose_gc_was_delayed = 1;
+                        goto next_obj;
+                    }
+                }
+                if (jl_is_code_instance(jl_valueof(v))) {
+                    jl_code_instance_t *ci = (jl_code_instance_t*)jl_valueof(v);
+                    // Print the CI's method
+                    jl_method_instance_t *mi = ci->def;
+                    jl_method_t *m = mi->def.method;
+                    jl_(m);
+                    jl_safe_printf("=====\n");
+                }
                 *pfl = v;
                 pfl = &v->next;
                 pfl_begin = (pfl_begin != NULL) ? pfl_begin : pfl;
@@ -1485,6 +1499,7 @@ static void gc_sweep_page(gc_page_profiler_serializer_t *s, jl_gc_pool_t *p, jl_
                 has_marked |= gc_marked(bits);
                 freedall = 0;
             }
+        next_obj:
             v = (jl_taggedvalue_t*)((char*)v + osize);
         }
         assert(!freedall);

src/init.c

@@ -864,8 +864,6 @@ JL_DLLEXPORT void julia_init(JL_IMAGE_SEARCH rel)
 
 void jl_init_heartbeat(void);
 
-extern uv_mutex_t array_to_string_print_lock;
-
 static NOINLINE void _finish_julia_init(JL_IMAGE_SEARCH rel, jl_ptls_t ptls, jl_task_t *ct)
 {
     JL_TIMING(JULIA_INIT, JULIA_INIT);
@@ -913,8 +911,6 @@ static NOINLINE void _finish_julia_init(JL_IMAGE_SEARCH rel, jl_ptls_t ptls, jl_
     jl_start_gc_threads();
     uv_barrier_wait(&thread_init_done);
 
-    uv_mutex_init(&array_to_string_print_lock);
-
     jl_init_heartbeat();
 
     jl_gc_enable(1);

src/julia.h

@@ -98,8 +98,7 @@ struct _jl_taggedvalue_bits {
     // Bit to indicate whether a call to `jl_array_to_string` is in-flight
     // Mostly used to implement a poor-man's dynamic race detector.
     // See usage in `jl_array_to_string`.
-#define ARRAY_TO_STRING_IN_FLIGHT_BIT_OFFSET (3)
-    uintptr_t array_to_string_in_flight:1;
+    uintptr_t obj_whose_gc_was_delayed:1;
 #ifdef _P64
     uintptr_t tag:60;
 #else