kernel: remove legacy fields in _kernel

UP should just use _kernel.cpus[0].

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

arch/arc/include/swap_macros.h

@@ -307,13 +307,13 @@
 	ld \reg2, [\reg1, ___cpu_t_nested_OFFSET]
 #else
 	mov \reg1, _kernel
-	ld \reg2, [\reg1, ___kernel_t_nested_OFFSET]
+	ld \reg2, [\reg1, _kernel_offset_to_nested]
 #endif
 	add \reg2, \reg2, 1
 #ifdef CONFIG_SMP
 	st \reg2, [\reg1, ___cpu_t_nested_OFFSET]
 #else
-	st \reg2, [\reg1, ___kernel_t_nested_OFFSET]
+	st \reg2, [\reg1, _kernel_offset_to_nested]
 #endif
 	cmp \reg2, 1
 .endm
@@ -329,13 +329,13 @@
 	ld \reg2, [\reg1, ___cpu_t_nested_OFFSET]
 #else
 	mov \reg1, _kernel
-	ld \reg2, [\reg1, ___kernel_t_nested_OFFSET]
+	ld \reg2, [\reg1, _kernel_offset_to_nested]
 #endif
 	sub \reg2, \reg2, 1
 #ifdef CONFIG_SMP
 	st \reg2, [\reg1, ___cpu_t_nested_OFFSET]
 #else
-	st \reg2, [\reg1, ___kernel_t_nested_OFFSET]
+	st \reg2, [\reg1, _kernel_offset_to_nested]
 #endif
 .endm
 

arch/arm/include/aarch64/exc.h

@@ -34,7 +34,7 @@ extern void z_arm64_offload(void);
 
 static ALWAYS_INLINE bool arch_is_in_isr(void)
 {
-	return _kernel.nested != 0U;
+	return _kernel.cpus[0].nested != 0U;
 }
 
 

arch/nios2/core/irq_manage.c

@@ -85,7 +85,7 @@ void _enter_irq(u32_t ipending)
 	read_timer_start_of_isr();
 #endif
 
-	_kernel.nested++;
+	_kernel.cpus[0].nested++;
 
 #ifdef CONFIG_IRQ_OFFLOAD
 	z_irq_do_offload();
@@ -113,7 +113,7 @@ void _enter_irq(u32_t ipending)
 #endif
 	}
 
-	_kernel.nested--;
+	_kernel.cpus[0].nested--;
 #ifdef CONFIG_STACK_SENTINEL
 	z_check_stack_sentinel();
 #endif

arch/nios2/include/kernel_arch_func.h

@@ -43,7 +43,7 @@ FUNC_NORETURN void z_nios2_fatal_error(unsigned int reason,
 
 static inline bool arch_is_in_isr(void)
 {
-	return _kernel.nested != 0U;
+	return _kernel.cpus[0].nested != 0U;
 }
 
 #ifdef CONFIG_IRQ_OFFLOAD

arch/posix/core/swap.c

@@ -22,16 +22,16 @@
 int arch_swap(unsigned int key)
 {
 	/*
-	 * struct k_thread * _kernel.current is the currently runnig thread
+	 * struct k_thread * _current is the currently runnig thread
 	 * struct k_thread * _kernel.ready_q.cache contains the next thread to
 	 * run (cannot be NULL)
 	 *
 	 * Here a "real" arch would save all processor registers, stack pointer
 	 * and so forth.  But we do not need to do so because we use posix
 	 * threads => those are all nicely kept by the native OS kernel
 	 */
-	_kernel.current->callee_saved.key = key;
-	_kernel.current->callee_saved.retval = -EAGAIN;
+	_current->callee_saved.key = key;
+	_current->callee_saved.retval = -EAGAIN;
 
 	/* retval may be modified with a call to
 	 * arch_thread_return_value_set()
@@ -43,10 +43,10 @@ int arch_swap(unsigned int key)
 
 	posix_thread_status_t *this_thread_ptr  =
 		(posix_thread_status_t *)
-		_kernel.current->callee_saved.thread_status;
+		_current->callee_saved.thread_status;
 
 
-	_kernel.current = _kernel.ready_q.cache;
+	_current = _kernel.ready_q.cache;
 
 	/*
 	 * Here a "real" arch would load all processor registers for the thread
@@ -59,9 +59,9 @@ int arch_swap(unsigned int key)
 
 	/* When we continue, _kernel->current points back to this thread */
 
-	irq_unlock(_kernel.current->callee_saved.key);
+	irq_unlock(_current->callee_saved.key);
 
-	return _kernel.current->callee_saved.retval;
+	return _current->callee_saved.retval;
 }
 
 
@@ -83,7 +83,7 @@ void arch_switch_to_main_thread(struct k_thread *main_thread,
 
 	sys_trace_thread_switched_out();
 
-	_kernel.current = _kernel.ready_q.cache;
+	_current = _kernel.ready_q.cache;
 
 	sys_trace_thread_switched_in();
 

arch/posix/include/kernel_arch_func.h

@@ -41,7 +41,7 @@ arch_thread_return_value_set(struct k_thread *thread, unsigned int value)
 
 static inline bool arch_is_in_isr(void)
 {
-	return _kernel.nested != 0U;
+	return _kernel.cpus[0].nested != 0U;
 }
 
 #endif /* _ASMLANGUAGE */

arch/riscv/core/isr.S

@@ -270,7 +270,7 @@ is_interrupt:
 	RV_OP_STOREREG t0, 0x00(sp)
 
 on_irq_stack:
-	/* Increment _kernel.nested variable */
+	/* Increment _kernel.cpus[0].nested variable */
 	lw t3, _kernel_offset_to_nested(t2)
 	addi t3, t3, 1
 	sw t3, _kernel_offset_to_nested(t2)
@@ -337,7 +337,7 @@ on_thread_stack:
 	/* Get reference to _kernel */
 	la t1, _kernel
 
-	/* Decrement _kernel.nested variable */
+	/* Decrement _kernel.cpus[0].nested variable */
 	lw t2, _kernel_offset_to_nested(t1)
 	addi t2, t2, -1
 	sw t2, _kernel_offset_to_nested(t1)

arch/riscv/include/kernel_arch_func.h

@@ -37,7 +37,7 @@ FUNC_NORETURN void z_riscv_fatal_error(unsigned int reason,
 
 static inline bool arch_is_in_isr(void)
 {
-	return _kernel.nested != 0U;
+	return _kernel.cpus[0].nested != 0U;
 }
 
 #ifdef CONFIG_IRQ_OFFLOAD

arch/x86/include/kernel_arch_func.h

@@ -31,7 +31,7 @@ static inline bool arch_is_in_isr(void)
 	__asm__ volatile ("popf");
 	return ret;
 #else
-	return _kernel.nested != 0U;
+	return _kernel.cpus[0].nested != 0U;
 #endif
 }
 

boards/posix/native_posix/irq_handler.c

@@ -76,11 +76,11 @@ void posix_irq_handler(void)
 		return;
 	}
 
-	if (_kernel.nested == 0) {
+	if (_kernel.cpus[0].nested == 0) {
 		may_swap = 0;
 	}
 
-	_kernel.nested++;
+	_kernel.cpus[0].nested++;
 
 	while ((irq_nbr = hw_irq_ctrl_get_highest_prio_irq()) != -1) {
 		int last_current_running_prio = hw_irq_ctrl_get_cur_prio();
@@ -96,7 +96,7 @@ void posix_irq_handler(void)
 		hw_irq_ctrl_set_cur_prio(last_current_running_prio);
 	}
 
-	_kernel.nested--;
+	_kernel.cpus[0].nested--;
 
 	/* Call swap if all the following is true:
 	 * 1) may_swap was enabled

boards/posix/nrf52_bsim/irq_handler.c

@@ -133,11 +133,11 @@ void posix_irq_handler(void)
 		return;
 	}
 
-	if (_kernel.nested == 0) {
+	if (_kernel.cpus[0].nested == 0) {
 		may_swap = 0;
 	}
 
-	_kernel.nested++;
+	_kernel.cpus[0].nested++;
 
 	while ((irq_nbr = hw_irq_ctrl_get_highest_prio_irq()) != -1) {
 		int last_current_running_prio = hw_irq_ctrl_get_cur_prio();
@@ -153,7 +153,7 @@ void posix_irq_handler(void)
 		hw_irq_ctrl_set_cur_prio(last_current_running_prio);
 	}
 
-	_kernel.nested--;
+	_kernel.cpus[0].nested--;
 
 	/* Call swap if all the following is true:
 	 * 1) may_swap was enabled

include/arch/x86/ia32/arch.h

@@ -253,7 +253,7 @@ static inline void arch_isr_direct_header(void)
 	/* We're not going to unlock IRQs, but we still need to increment this
 	 * so that arch_is_in_isr() works
 	 */
-	++_kernel.nested;
+	++_kernel.cpus[0].nested;
 }
 
 /*
@@ -269,15 +269,15 @@ static inline void arch_isr_direct_footer(int swap)
 #if defined(CONFIG_TRACING)
 	sys_trace_isr_exit();
 #endif
-	--_kernel.nested;
+	--_kernel.cpus[0].nested;
 
 	/* Call swap if all the following is true:
 	 *
 	 * 1) swap argument was enabled to this function
 	 * 2) We are not in a nested interrupt
 	 * 3) Next thread to run in the ready queue is not this thread
 	 */
-	if (swap != 0 && _kernel.nested == 0 &&
+	if (swap != 0 && _kernel.cpus[0].nested == 0 &&
 	    _kernel.ready_q.cache != _current) {
 		unsigned int flags;
 

include/kernel_structs.h

@@ -133,25 +133,7 @@ struct _cpu {
 typedef struct _cpu _cpu_t;
 
 struct z_kernel {
-	/* For compatibility with pre-SMP code, union the first CPU
-	 * record with the legacy fields so code can continue to use
-	 * the "_kernel.XXX" expressions and assembly offsets.
-	 */
-	union {
-		struct _cpu cpus[CONFIG_MP_NUM_CPUS];
-#ifndef CONFIG_SMP
-		struct {
-			/* nested interrupt count */
-			u32_t nested;
-
-			/* interrupt stack pointer base */
-			char *irq_stack;
-
-			/* currently scheduled thread */
-			struct k_thread *current;
-		};
-#endif
-	};
+	struct _cpu cpus[CONFIG_MP_NUM_CPUS];
 
 #ifdef CONFIG_SYS_CLOCK_EXISTS
 	/* queue of timeouts */
@@ -204,7 +186,7 @@ bool z_smp_cpu_mobile(void);
 
 #else
 #define _current_cpu (&_kernel.cpus[0])
-#define _current _kernel.current
+#define _current _kernel.cpus[0].current
 #endif
 
 #define _timeout_q _kernel.timeout_q

kernel/include/kernel_offsets.h

@@ -23,12 +23,6 @@
 
 GEN_ABS_SYM_BEGIN(_OffsetAbsSyms)
 
-#ifndef CONFIG_SMP
-GEN_OFFSET_SYM(_kernel_t, current);
-GEN_OFFSET_SYM(_kernel_t, nested);
-GEN_OFFSET_SYM(_kernel_t, irq_stack);
-#endif
-
 GEN_OFFSET_SYM(_cpu_t, current);
 GEN_OFFSET_SYM(_cpu_t, nested);
 GEN_OFFSET_SYM(_cpu_t, irq_stack);

kernel/include/offsets_short.h

@@ -13,15 +13,18 @@
 /* kernel */
 
 /* main */
-
+#ifndef CONFIG_SMP
+/* Relies on _kernel.cpu being the first member of _kernel and having 1 element
+ */
 #define _kernel_offset_to_nested \
-	(___kernel_t_nested_OFFSET)
+	(___cpu_t_nested_OFFSET)
 
 #define _kernel_offset_to_irq_stack \
-	(___kernel_t_irq_stack_OFFSET)
+	(___cpu_t_irq_stack_OFFSET)
 
 #define _kernel_offset_to_current \
-	(___kernel_t_current_OFFSET)
+	(___cpu_t_current_OFFSET)
+#endif /* CONFIG_SMP */
 
 #define _kernel_offset_to_idle \
 	(___kernel_t_idle_OFFSET)

subsys/debug/openocd.c

@@ -25,6 +25,10 @@ enum {
 	OPENOCD_OFFSET_T_COOP_FLOAT,
 };
 
+#if CONFIG_MP_NUM_CPUS > 1
+#error "This code doesn't work properly with multiple CPUs enabled"
+#endif
+
 /* Forward-compatibility notes: 1) Only append items to this table; otherwise
  * OpenOCD versions that expect less items will read garbage values.
  * 2) Avoid incompatible changes that affect the interpretation of existing
@@ -36,7 +40,7 @@ __attribute__((used, section(".openocd_dbg")))
 size_t _kernel_openocd_offsets[] = {
 	/* Version 0 starts */
 	[OPENOCD_OFFSET_VERSION] = 1,
-	[OPENOCD_OFFSET_K_CURR_THREAD] = offsetof(struct z_kernel, current),
+	[OPENOCD_OFFSET_K_CURR_THREAD] = offsetof(struct _cpu, current),
 	[OPENOCD_OFFSET_K_THREADS] = offsetof(struct z_kernel, threads),
 	[OPENOCD_OFFSET_T_ENTRY] = offsetof(struct k_thread, entry),
 	[OPENOCD_OFFSET_T_NEXT_THREAD] = offsetof(struct k_thread, next_thread),