diff --git a/kernel/sched.c b/kernel/sched.c
index 72d52a5854a68a..2827a41fd381bd 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -502,7 +502,7 @@ static void z_thread_halt(struct k_thread *thread, k_spinlock_key_t key,
 }
 
 
-void z_impl_k_thread_suspend(struct k_thread *thread)
+void z_impl_k_thread_suspend(k_tid_t thread)
 {
 	SYS_PORT_TRACING_OBJ_FUNC_ENTER(k_thread, suspend, thread);
 
@@ -524,7 +524,7 @@ void z_impl_k_thread_suspend(struct k_thread *thread)
 }
 
 #ifdef CONFIG_USERSPACE
-static inline void z_vrfy_k_thread_suspend(struct k_thread *thread)
+static inline void z_vrfy_k_thread_suspend(k_tid_t thread)
 {
 	K_OOPS(K_SYSCALL_OBJ(thread, K_OBJ_THREAD));
 	z_impl_k_thread_suspend(thread);
@@ -532,7 +532,7 @@ static inline void z_vrfy_k_thread_suspend(struct k_thread *thread)
 #include <zephyr/syscalls/k_thread_suspend_mrsh.c>
 #endif /* CONFIG_USERSPACE */
 
-void z_impl_k_thread_resume(struct k_thread *thread)
+void z_impl_k_thread_resume(k_tid_t thread)
 {
 	SYS_PORT_TRACING_OBJ_FUNC_ENTER(k_thread, resume, thread);
 
@@ -553,7 +553,7 @@ void z_impl_k_thread_resume(struct k_thread *thread)
 }
 
 #ifdef CONFIG_USERSPACE
-static inline void z_vrfy_k_thread_resume(struct k_thread *thread)
+static inline void z_vrfy_k_thread_resume(k_tid_t thread)
 {
 	K_OOPS(K_SYSCALL_OBJ(thread, K_OBJ_THREAD));
 	z_impl_k_thread_resume(thread);
@@ -1215,7 +1215,7 @@ static inline int32_t z_vrfy_k_sleep(k_timeout_t timeout)
 #include <zephyr/syscalls/k_sleep_mrsh.c>
 #endif /* CONFIG_USERSPACE */
 
-int32_t z_impl_k_usleep(int us)
+int32_t z_impl_k_usleep(int32_t us)
 {
 	int32_t ticks;
 
@@ -1232,7 +1232,7 @@ int32_t z_impl_k_usleep(int us)
 }
 
 #ifdef CONFIG_USERSPACE
-static inline int32_t z_vrfy_k_usleep(int us)
+static inline int32_t z_vrfy_k_usleep(int32_t us)
 {
 	return z_impl_k_usleep(us);
 }
@@ -1442,7 +1442,7 @@ void z_thread_abort(struct k_thread *thread)
 }
 
 #if !defined(CONFIG_ARCH_HAS_THREAD_ABORT)
-void z_impl_k_thread_abort(struct k_thread *thread)
+void z_impl_k_thread_abort(k_tid_t thread)
 {
 	SYS_PORT_TRACING_OBJ_FUNC_ENTER(k_thread, abort, thread);
 
diff --git a/kernel/thread.c b/kernel/thread.c
index e39ecd3d7c81a4..212a08085f1251 100644
--- a/kernel/thread.c
+++ b/kernel/thread.c
@@ -135,14 +135,14 @@ static inline int z_vrfy_k_thread_priority_get(k_tid_t thread)
 #include <zephyr/syscalls/k_thread_priority_get_mrsh.c>
 #endif /* CONFIG_USERSPACE */
 
-int z_impl_k_thread_name_set(struct k_thread *thread, const char *value)
+int z_impl_k_thread_name_set(k_tid_t thread, const char *str)
 {
 #ifdef CONFIG_THREAD_NAME
 	if (thread == NULL) {
 		thread = _current;
 	}
 
-	strncpy(thread->name, value, CONFIG_THREAD_MAX_NAME_LEN - 1);
+	strncpy(thread->name, str, CONFIG_THREAD_MAX_NAME_LEN - 1);
 	thread->name[CONFIG_THREAD_MAX_NAME_LEN - 1] = '\0';
 
 	SYS_PORT_TRACING_OBJ_FUNC(k_thread, name_set, thread, 0);
@@ -150,7 +150,7 @@ int z_impl_k_thread_name_set(struct k_thread *thread, const char *value)
 	return 0;
 #else
 	ARG_UNUSED(thread);
-	ARG_UNUSED(value);
+	ARG_UNUSED(str);
 
 	SYS_PORT_TRACING_OBJ_FUNC(k_thread, name_set, thread, -ENOSYS);
 
@@ -159,7 +159,7 @@ int z_impl_k_thread_name_set(struct k_thread *thread, const char *value)
 }
 
 #ifdef CONFIG_USERSPACE
-static inline int z_vrfy_k_thread_name_set(struct k_thread *thread, const char *str)
+static inline int z_vrfy_k_thread_name_set(k_tid_t thread, const char *str)
 {
 #ifdef CONFIG_THREAD_NAME
 	char name[CONFIG_THREAD_MAX_NAME_LEN];
@@ -340,7 +340,7 @@ void z_check_stack_sentinel(void)
 }
 #endif /* CONFIG_STACK_SENTINEL */
 
-void z_impl_k_thread_start(struct k_thread *thread)
+void z_impl_k_thread_start(k_tid_t thread)
 {
 	SYS_PORT_TRACING_OBJ_FUNC(k_thread, start, thread);
 
@@ -348,7 +348,7 @@ void z_impl_k_thread_start(struct k_thread *thread)
 }
 
 #ifdef CONFIG_USERSPACE
-static inline void z_vrfy_k_thread_start(struct k_thread *thread)
+static inline void z_vrfy_k_thread_start(k_tid_t thread)
 {
 	K_OOPS(K_SYSCALL_OBJ(thread, K_OBJ_THREAD));
 	return z_impl_k_thread_start(thread);