kernel: thread_monitor: reafactor and remove duplicate code

Refactor code and remove duplication, same code almost being repeated 4
times.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>

kernel/thread_monitor.c

@@ -34,110 +34,77 @@ void z_thread_monitor_exit(struct k_thread *thread)
 	k_spin_unlock(&z_thread_monitor_lock, key);
 }
 
-
-void k_thread_foreach(k_thread_user_cb_t user_cb, void *user_data)
+/*
+ * Helper function to iterate over threads with optional filtering and locking behavior.
+ */
+static void thread_foreach_helper(k_thread_user_cb_t user_cb, void *user_data,
+		bool unlocked, bool filter_by_cpu, unsigned int cpu)
 {
 	struct k_thread *thread;
 	k_spinlock_key_t key;
 
 	__ASSERT(user_cb != NULL, "user_cb can not be NULL");
 
-	/*
-	 * Lock is needed to make sure that the _kernel.threads is not being
-	 * modified by the user_cb either directly or indirectly.
-	 * The indirect ways are through calling k_thread_create and
-	 * k_thread_abort from user_cb.
-	 */
-	key = k_spin_lock(&z_thread_monitor_lock);
+	if (filter_by_cpu) {
+		__ASSERT(cpu < CONFIG_MP_MAX_NUM_CPUS, "cpu filter out of bounds");
+	}
 
-	SYS_PORT_TRACING_FUNC_ENTER(k_thread, foreach);
+	key = k_spin_lock(&z_thread_monitor_lock);
 
 	for (thread = _kernel.threads; thread; thread = thread->next_thread) {
-		user_cb(thread, user_data);
-	}
+		/* cpu is only defined when SMP=y*/
+#ifdef CONFIG_SMP
+		bool on_cpu = (thread->base.cpu == cpu);
+#else
+		bool on_cpu = false;
+#endif
+		if (filter_by_cpu && !on_cpu) {
+			continue;
+		}
 
-	SYS_PORT_TRACING_FUNC_EXIT(k_thread, foreach);
+		if (unlocked) {
+			k_spin_unlock(&z_thread_monitor_lock, key);
+			user_cb(thread, user_data);
+			key = k_spin_lock(&z_thread_monitor_lock);
+		} else {
+			user_cb(thread, user_data);
+		}
+	}
 
 	k_spin_unlock(&z_thread_monitor_lock, key);
 }
 
-void k_thread_foreach_unlocked(k_thread_user_cb_t user_cb, void *user_data)
+/*
+ * Public API functions using the helper.
+ */
+void k_thread_foreach(k_thread_user_cb_t user_cb, void *user_data)
 {
-	struct k_thread *thread;
-	k_spinlock_key_t key;
-
-	__ASSERT(user_cb != NULL, "user_cb can not be NULL");
-
-	key = k_spin_lock(&z_thread_monitor_lock);
+	SYS_PORT_TRACING_FUNC_ENTER(k_thread, foreach);
+	thread_foreach_helper(user_cb, user_data, false, false, 0);
+	SYS_PORT_TRACING_FUNC_EXIT(k_thread, foreach);
+}
 
+void k_thread_foreach_unlocked(k_thread_user_cb_t user_cb, void *user_data)
+{
 	SYS_PORT_TRACING_FUNC_ENTER(k_thread, foreach_unlocked);
-
-	for (thread = _kernel.threads; thread; thread = thread->next_thread) {
-		k_spin_unlock(&z_thread_monitor_lock, key);
-		user_cb(thread, user_data);
-		key = k_spin_lock(&z_thread_monitor_lock);
-	}
-
+	thread_foreach_helper(user_cb, user_data, true, false, 0);
 	SYS_PORT_TRACING_FUNC_EXIT(k_thread, foreach_unlocked);
-
-	k_spin_unlock(&z_thread_monitor_lock, key);
-
 }
 
 #ifdef CONFIG_SMP
 void k_thread_foreach_filter_by_cpu(unsigned int cpu, k_thread_user_cb_t user_cb,
-				  void *user_data)
+		void *user_data)
 {
-	struct k_thread *thread;
-	k_spinlock_key_t key;
-
-	__ASSERT(user_cb != NULL, "user_cb can not be NULL");
-	__ASSERT(cpu < CONFIG_MP_MAX_NUM_CPUS, "cpu filter out of bounds");
-
-	/*
-	 * Lock is needed to make sure that the _kernel.threads is not being
-	 * modified by the user_cb either directly or indirectly.
-	 * The indirect ways are through calling k_thread_create and
-	 * k_thread_abort from user_cb.
-	 */
-	key = k_spin_lock(&z_thread_monitor_lock);
-
 	SYS_PORT_TRACING_FUNC_ENTER(k_thread, foreach);
-
-	for (thread = _kernel.threads; thread; thread = thread->next_thread) {
-		if (thread->base.cpu == cpu) {
-			user_cb(thread, user_data);
-		}
-	}
-
+	thread_foreach_helper(user_cb, user_data, false, true, cpu);
 	SYS_PORT_TRACING_FUNC_EXIT(k_thread, foreach);
-
-	k_spin_unlock(&z_thread_monitor_lock, key);
 }
 
 void k_thread_foreach_unlocked_filter_by_cpu(unsigned int cpu, k_thread_user_cb_t user_cb,
-					     void *user_data)
+		void *user_data)
 {
-	struct k_thread *thread;
-	k_spinlock_key_t key;
-
-	__ASSERT(user_cb != NULL, "user_cb can not be NULL");
-	__ASSERT(cpu < CONFIG_MP_MAX_NUM_CPUS, "cpu filter out of bounds");
-
-	key = k_spin_lock(&z_thread_monitor_lock);
-
 	SYS_PORT_TRACING_FUNC_ENTER(k_thread, foreach_unlocked);
-
-	for (thread = _kernel.threads; thread; thread = thread->next_thread) {
-		if (thread->base.cpu == cpu) {
-			k_spin_unlock(&z_thread_monitor_lock, key);
-			user_cb(thread, user_data);
-			key = k_spin_lock(&z_thread_monitor_lock);
-		}
-	}
-
+	thread_foreach_helper(user_cb, user_data, true, true, cpu);
 	SYS_PORT_TRACING_FUNC_EXIT(k_thread, foreach_unlocked);
-
-	k_spin_unlock(&z_thread_monitor_lock, key);
 }
 #endif /* CONFIG_SMP */