Add GC.stat about pages swept by sweep thread

Author: etiennebarrie

gc/default/default.c

@@ -648,6 +648,8 @@ typedef struct rb_objspace {
         struct timespec ruby_thread_sweep_cpu_start_time;
         struct timespec ruby_thread_sweep_wall_start_time;
 #endif
+        size_t pages_swept_by_sweep_thread;
+        size_t pages_swept_by_sweep_thread_had_deferred_free_objects;
 
         /* Weak references */
         size_t weak_references_count;
@@ -4556,6 +4558,10 @@ gc_pre_sweep_page(rb_objspace_t *objspace, rb_heap_t *heap, struct heap_page *pa
         }
         p += BITS_BITLENGTH * BASE_SLOT_SIZE;
     }
+    objspace->profile.pages_swept_by_sweep_thread++;
+    if (page->pre_deferred_free_slots > 0) {
+        objspace->profile.pages_swept_by_sweep_thread_had_deferred_free_objects++;
+    }
     psweep_debug(1, "[sweep] gc_pre_sweep_page(heap:%p page:%p) done, deferred free:%d\n", heap, page, page->pre_deferred_free_slots);
 }
 
@@ -9124,6 +9130,8 @@ enum gc_stat_sym {
     gc_stat_sym_remembered_wb_unprotected_objects_limit,
     gc_stat_sym_old_objects,
     gc_stat_sym_old_objects_limit,
+    gc_stat_sym_pages_swept_by_sweep_thread,
+    gc_stat_sym_pages_swept_by_sweep_thread_had_deferred_free_objects,
 #if RGENGC_ESTIMATE_OLDMALLOC
     gc_stat_sym_oldmalloc_increase_bytes,
     gc_stat_sym_oldmalloc_increase_bytes_limit,
@@ -9175,6 +9183,8 @@ setup_gc_stat_symbols(void)
         S(remembered_wb_unprotected_objects_limit);
         S(old_objects);
         S(old_objects_limit);
+        S(pages_swept_by_sweep_thread);
+        S(pages_swept_by_sweep_thread_had_deferred_free_objects);
 #if RGENGC_ESTIMATE_OLDMALLOC
         S(oldmalloc_increase_bytes);
         S(oldmalloc_increase_bytes_limit);
@@ -9257,6 +9267,8 @@ rb_gc_impl_stat(void *objspace_ptr, VALUE hash_or_sym)
     SET(remembered_wb_unprotected_objects_limit, objspace->rgengc.uncollectible_wb_unprotected_objects_limit);
     SET(old_objects, objspace->rgengc.old_objects);
     SET(old_objects_limit, objspace->rgengc.old_objects_limit);
+    SET(pages_swept_by_sweep_thread, objspace->profile.pages_swept_by_sweep_thread);
+    SET(pages_swept_by_sweep_thread_had_deferred_free_objects, objspace->profile.pages_swept_by_sweep_thread_had_deferred_free_objects);
 #if RGENGC_ESTIMATE_OLDMALLOC
     SET(oldmalloc_increase_bytes, objspace->malloc_counters.oldmalloc_increase);
     SET(oldmalloc_increase_bytes_limit, objspace->rgengc.oldmalloc_increase_limit);