blocking_region_begin  100 thread.c       static void inline blocking_region_begin(rb_thread_t *th, struct rb_blocking_region_buffer *region,
blocking_region_begin  124 thread.c           blocking_region_begin(__th, &__region, ubf, ubfarg); \
blocking_region_begin  984 thread.c           blocking_region_begin(th, region, ubf_select, th);
blocking_region_begin 1123 thread.c           blocking_region_begin(th, brb, prev_unblock.func, prev_unblock.arg);