kernel: implement some more system calls

These are needed to demonstrate the Philosophers demo with threads
running in user mode.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>

include/kernel.h

@@ -599,7 +599,7 @@ extern FUNC_NORETURN void k_thread_user_mode_enter(k_thread_entry_t entry,
  *
  * @return N/A
  */
-extern void k_sleep(s32_t duration);
+__syscall void k_sleep(s32_t duration);
 
 /**
  * @brief Cause the current thread to busy wait.
@@ -640,7 +640,7 @@ extern void k_wakeup(k_tid_t thread);
  *
  * @return ID of current thread.
  */
-extern k_tid_t k_current_get(void);
+__syscall k_tid_t k_current_get(void);
 
 /**
  * @brief Cancel thread performing a delayed start.
@@ -779,7 +779,7 @@ struct _static_thread_data {
  *
  * @return Priority of @a thread.
  */
-extern int  k_thread_priority_get(k_tid_t thread);
+__syscall int k_thread_priority_get(k_tid_t thread);
 
 /**
  * @brief Set a thread's priority.
@@ -1414,7 +1414,7 @@ static inline void k_disable_sys_clock_always_on(void)
  *
  * @return Current uptime.
  */
-extern u32_t k_uptime_get_32(void);
+__syscall u32_t k_uptime_get_32(void);
 
 /**
  * @brief Get elapsed time.

kernel/sched.c

@@ -10,6 +10,7 @@
 #include <ksched.h>
 #include <wait_q.h>
 #include <misc/util.h>
+#include <syscall_handler.h>
 
 /* the only struct _kernel instance */
 struct _kernel _kernel = {0};
@@ -257,11 +258,26 @@ int __must_switch_threads(void)
 #endif
 }
 
-int  k_thread_priority_get(k_tid_t thread)
+int _impl_k_thread_priority_get(k_tid_t thread)
 {
 	return thread->base.prio;
 }
 
+#ifdef CONFIG_USERSPACE
+u32_t _handler_k_thread_priority_get(u32_t arg1, u32_t arg2, u32_t arg3,
+				     u32_t arg4, u32_t arg5, u32_t arg6,
+				     void *ssf)
+{
+	struct k_thread *thread;
+
+	_SYSCALL_ARG1;
+
+	thread = (struct k_thread *)arg1;
+	_SYSCALL_IS_OBJ(thread, K_OBJ_THREAD, 0, ssf);
+	return (u32_t)_impl_k_thread_priority_get(thread);
+}
+#endif
+
 void k_thread_priority_set(k_tid_t tid, int prio)
 {
 	/*
@@ -322,7 +338,7 @@ void k_yield(void)
 	}
 }
 
-void k_sleep(s32_t duration)
+void _impl_k_sleep(s32_t duration)
 {
 #ifdef CONFIG_MULTITHREADING
 	/* volatile to guarantee that irq_lock() is executed after ticks is
@@ -352,6 +368,19 @@ void k_sleep(s32_t duration)
 #endif
 }
 
+#ifdef CONFIG_USERSPACE
+u32_t _handler_k_sleep(u32_t arg1, u32_t arg2, u32_t arg3,
+		       u32_t arg4, u32_t arg5, u32_t arg6, void *ssf)
+{
+	_SYSCALL_ARG1;
+
+	_SYSCALL_VERIFY(arg1 != K_FOREVER, ssf);
+	_impl_k_sleep(arg1);
+
+	return 0;
+}
+#endif
+
 void k_wakeup(k_tid_t thread)
 {
 	int key = irq_lock();
@@ -376,11 +405,21 @@ void k_wakeup(k_tid_t thread)
 	}
 }
 
-k_tid_t k_current_get(void)
+k_tid_t _impl_k_current_get(void)
 {
 	return _current;
 }
 
+#ifdef CONFIG_USERSPACE
+u32_t _handler_k_current_get(u32_t arg1, u32_t arg2, u32_t arg3, u32_t arg4,
+			     u32_t arg5, u32_t arg6, void *ssf)
+{
+	_SYSCALL_ARG0;
+
+	return (u32_t)_impl_k_current_get();
+}
+#endif
+
 #ifdef CONFIG_TIMESLICING
 extern s32_t _time_slice_duration;    /* Measured in ms */
 extern s32_t _time_slice_elapsed;     /* Measured in ms */

kernel/sys_clock.c

@@ -12,6 +12,7 @@
 #include <linker/sections.h>
 #include <wait_q.h>
 #include <drivers/system_timer.h>
+#include <syscall_handler.h>
 
 #ifdef CONFIG_SYS_CLOCK_EXISTS
 #ifdef _NON_OPTIMIZED_TICKS_PER_SEC
@@ -68,7 +69,7 @@ u32_t _tick_get_32(void)
 }
 FUNC_ALIAS(_tick_get_32, sys_tick_get_32, u32_t);
 
-u32_t k_uptime_get_32(void)
+u32_t _impl_k_uptime_get_32(void)
 {
 #ifdef CONFIG_TICKLESS_KERNEL
 	__ASSERT(_sys_clock_always_on,
@@ -77,6 +78,19 @@ u32_t k_uptime_get_32(void)
 	return __ticks_to_ms(_tick_get_32());
 }
 
+#ifdef CONFIG_USERSPACE
+u32_t _handler_k_uptime_get_32(u32_t arg1, u32_t arg2, u32_t arg3,
+			       u32_t arg4, u32_t arg5, u32_t arg6, void *ssf)
+{
+	_SYSCALL_ARG0;
+
+#ifdef CONFIG_TICKLESS_KERNEL
+	_SYSCALL_VERIFY(_sys_clock_always_on, ssf);
+#endif
+	return _impl_k_uptime_get_32();
+}
+#endif
+
 /**
  *
  * @brief Return the current system tick count