interrupt_exec

introduce
- rb_threadptr_interrupt_exec
- rb_ractor_interrupt_exec

to intercept the thread/ractor execution.

internal/thread.h

@@ -82,4 +82,25 @@ RUBY_SYMBOL_EXPORT_END
 int rb_threadptr_execute_interrupts(struct rb_thread_struct *th, int blocking_timing);
 bool rb_thread_mn_schedulable(VALUE thread);
 
+// interrupt exec
+
+typedef VALUE (rb_interrupt_exec_func_t)(void *data);
+
+enum rb_interrupt_exec_flag {
+    rb_interrupt_exec_flag_none = 0x00,
+    rb_interrupt_exec_flag_value_data = 0x01,
+};
+
+// interrupt the target_th and run func.
+struct rb_ractor_struct;
+
+void rb_threadptr_interrupt_exec(struct rb_thread_struct *target_th,
+                                 rb_interrupt_exec_func_t *func, void *data, enum rb_interrupt_exec_flag flags);
+
+// create a thread in the target_r and run func on the created thread.
+void rb_ractor_interrupt_exec(struct rb_ractor_struct *target_r,
+                              rb_interrupt_exec_func_t *func, void *data, enum rb_interrupt_exec_flag flags);
+
+void rb_threadptr_interrupt_exec_task_mark(struct rb_thread_struct *th);
+
 #endif /* INTERNAL_THREAD_H */

thread.c

@@ -342,25 +342,33 @@ unblock_function_clear(rb_thread_t *th)
 }
 
 static void
-rb_threadptr_interrupt_common(rb_thread_t *th, int trap)
+threadptr_interrupt_locked(rb_thread_t *th, bool trap)
 {
+    // th->interrupt_lock should be acquired here
+
     RUBY_DEBUG_LOG("th:%u trap:%d", rb_th_serial(th), trap);
 
+    if (trap) {
+        RUBY_VM_SET_TRAP_INTERRUPT(th->ec);
+    }
+    else {
+        RUBY_VM_SET_INTERRUPT(th->ec);
+    }
+
+    if (th->unblock.func != NULL) {
+        (th->unblock.func)(th->unblock.arg);
+    }
+    else {
+        /* none */
+    }
+}
+
+static void
+threadptr_interrupt(rb_thread_t *th, int trap)
+{
     rb_native_mutex_lock(&th->interrupt_lock);
     {
-        if (trap) {
+        threadptr_interrupt_locked(th, trap);
-            RUBY_VM_SET_TRAP_INTERRUPT(th->ec);
-        }
-        else {
-            RUBY_VM_SET_INTERRUPT(th->ec);
-        }
-
-        if (th->unblock.func != NULL) {
-            (th->unblock.func)(th->unblock.arg);
-        }
-        else {
-            /* none */
-        }
     }
     rb_native_mutex_unlock(&th->interrupt_lock);
 }
@@ -369,13 +377,13 @@ void
 rb_threadptr_interrupt(rb_thread_t *th)
 {
     RUBY_DEBUG_LOG("th:%u", rb_th_serial(th));
-    rb_threadptr_interrupt_common(th, 0);
+    threadptr_interrupt(th, false);
 }
 
 static void
 threadptr_trap_interrupt(rb_thread_t *th)
 {
-    rb_threadptr_interrupt_common(th, 1);
+    threadptr_interrupt(th, true);
 }
 
 static void
@@ -490,6 +498,7 @@ rb_thread_terminate_all(rb_thread_t *th)
 }
 
 void rb_threadptr_root_fiber_terminate(rb_thread_t *th);
+static void threadptr_interrupt_exec_cleanup(rb_thread_t *th);
 
 static void
 thread_cleanup_func_before_exec(void *th_ptr)
@@ -500,6 +509,7 @@ thread_cleanup_func_before_exec(void *th_ptr)
     // The thread stack doesn't exist in the forked process:
     th->ec->machine.stack_start = th->ec->machine.stack_end = NULL;
 
+    threadptr_interrupt_exec_cleanup(th);
     rb_threadptr_root_fiber_terminate(th);
 }
 
@@ -2418,6 +2428,8 @@ threadptr_get_interrupts(rb_thread_t *th)
     return interrupt & (rb_atomic_t)~ec->interrupt_mask;
 }
 
+static void threadptr_interrupt_exec_exec(rb_thread_t *th);
+
 int
 rb_threadptr_execute_interrupts(rb_thread_t *th, int blocking_timing)
 {
@@ -2449,17 +2461,29 @@ rb_threadptr_execute_interrupts(rb_thread_t *th, int blocking_timing)
             rb_postponed_job_flush(th->vm);
         }
 
-        /* signal handling */
+        if (trap_interrupt) {
-        if (trap_interrupt && (th == th->vm->ractor.main_thread)) {
+            /* signal handling */
-            enum rb_thread_status prev_status = th->status;
+            if (th == th->vm->ractor.main_thread) {
+                enum rb_thread_status prev_status = th->status;
 
-            th->status = THREAD_RUNNABLE;
+                th->status = THREAD_RUNNABLE;
-            {
+                {
-                while ((sig = rb_get_next_signal()) != 0) {
+                    while ((sig = rb_get_next_signal()) != 0) {
-                    ret |= rb_signal_exec(th, sig);
+                        ret |= rb_signal_exec(th, sig);
+                    }
                 }
+                th->status = prev_status;
+            }
+
+            if (!ccan_list_empty(&th->interrupt_exec_tasks)) {
+                enum rb_thread_status prev_status = th->status;
+
+                th->status = THREAD_RUNNABLE;
+                {
+                    threadptr_interrupt_exec_exec(th);
+                }
+                th->status = prev_status;
             }
-            th->status = prev_status;
         }
 
         /* exception from another thread */
@@ -4700,6 +4724,7 @@ rb_thread_atfork_internal(rb_thread_t *th, void (*atfork)(rb_thread_t *, const r
 
     /* may be held by any thread in parent */
     rb_native_mutex_initialize(&th->interrupt_lock);
+    ccan_list_head_init(&th->interrupt_exec_tasks);
 
     vm->fork_gen++;
     rb_ractor_sleeper_threads_clear(th->ractor);
@@ -5920,3 +5945,120 @@ rb_internal_thread_specific_set(VALUE thread_val, rb_internal_thread_specific_ke
 
     th->specific_storage[key] = data;
 }
+
+// interrupt_exec
+
+struct rb_interrupt_exec_task {
+    struct ccan_list_node node;
+
+    rb_interrupt_exec_func_t *func;
+    void *data;
+    enum rb_interrupt_exec_flag flags;
+};
+
+void
+rb_threadptr_interrupt_exec_task_mark(rb_thread_t *th)
+{
+    struct rb_interrupt_exec_task *task;
+
+    ccan_list_for_each(&th->interrupt_exec_tasks, task, node) {
+        if (task->flags & rb_interrupt_exec_flag_value_data) {
+            rb_gc_mark((VALUE)task->data);
+        }
+    }
+}
+
+// native thread safe
+// th should be available
+void
+rb_threadptr_interrupt_exec(rb_thread_t *th, rb_interrupt_exec_func_t *func, void *data, enum rb_interrupt_exec_flag flags)
+{
+    // should not use ALLOC
+    struct rb_interrupt_exec_task *task = ALLOC(struct rb_interrupt_exec_task);
+    *task = (struct rb_interrupt_exec_task) {
+        .flags = flags,
+        .func = func,
+        .data = data,
+    };
+
+    rb_native_mutex_lock(&th->interrupt_lock);
+    {
+        ccan_list_add_tail(&th->interrupt_exec_tasks, &task->node);
+        threadptr_interrupt_locked(th, true);
+    }
+    rb_native_mutex_unlock(&th->interrupt_lock);
+}
+
+static void
+threadptr_interrupt_exec_exec(rb_thread_t *th)
+{
+    while (1) {
+        struct rb_interrupt_exec_task *task;
+
+        rb_native_mutex_lock(&th->interrupt_lock);
+        {
+            task = ccan_list_pop(&th->interrupt_exec_tasks, struct rb_interrupt_exec_task, node);
+        }
+        rb_native_mutex_unlock(&th->interrupt_lock);
+
+        if (task) {
+            (*task->func)(task->data);
+            ruby_xfree(task);
+        }
+        else {
+            break;
+        }
+    }
+}
+
+static void
+threadptr_interrupt_exec_cleanup(rb_thread_t *th)
+{
+    rb_native_mutex_lock(&th->interrupt_lock);
+    {
+        struct rb_interrupt_exec_task *task;
+
+        while ((task = ccan_list_pop(&th->interrupt_exec_tasks, struct rb_interrupt_exec_task, node)) != NULL) {
+            ruby_xfree(task);
+        }
+    }
+    rb_native_mutex_unlock(&th->interrupt_lock);
+}
+
+struct interrupt_ractor_new_thread_data {
+    rb_interrupt_exec_func_t *func;
+    void *data;
+};
+
+static VALUE
+interrupt_ractor_new_thread_func(void *data)
+{
+    struct interrupt_ractor_new_thread_data d = *(struct interrupt_ractor_new_thread_data *)data;
+    ruby_xfree(data);
+
+    d.func(d.data);
+    return Qnil;
+}
+
+static VALUE
+interrupt_ractor_func(void *data)
+{
+    rb_thread_create(interrupt_ractor_new_thread_func, data);
+    return Qnil;
+}
+
+// native thread safe
+// func/data should be native thread safe
+void
+rb_ractor_interrupt_exec(struct rb_ractor_struct *target_r,
+                         rb_interrupt_exec_func_t *func, void *data, enum rb_interrupt_exec_flag flags)
+{
+    struct interrupt_ractor_new_thread_data *d = ALLOC(struct interrupt_ractor_new_thread_data);
+
+    d->func = func;
+    d->data = data;
+    rb_thread_t *main_th = target_r->threads.main;
+    rb_threadptr_interrupt_exec(main_th, interrupt_ractor_func, d, flags);
+
+    // TODO MEMO: we can create a new thread in a ractor, but not sure how to do that now.
+}

vm.c

@@ -3491,6 +3491,8 @@ thread_mark(void *ptr)
 
     rb_gc_mark(th->scheduler);
 
+    rb_threadptr_interrupt_exec_task_mark(th);
+
     RUBY_MARK_LEAVE("thread");
 }
 
@@ -3644,6 +3646,8 @@ th_init(rb_thread_t *th, VALUE self, rb_vm_t *vm)
     th->report_on_exception = vm->thread_report_on_exception;
     th->ext_config.ractor_safe = true;
 
+    ccan_list_head_init(&th->interrupt_exec_tasks);
+
 #if USE_RUBY_DEBUG_LOG
     static rb_atomic_t thread_serial = 1;
     th->serial = RUBY_ATOMIC_FETCH_ADD(thread_serial, 1);

vm_core.h

@@ -1156,6 +1156,7 @@ typedef struct rb_thread_struct {
     struct rb_unblock_callback unblock;
     VALUE locking_mutex;
     struct rb_mutex_struct *keeping_mutexes;
+    struct ccan_list_head interrupt_exec_tasks;
 
     struct rb_waiting_list *join_list;