Stack Traces

API for managing stack backtracing More...

Files
file	stack.h
	Stack functions.

Macros
#define	THD_STACK_ALIGNMENT   8
	Required alignment for stack.
#define	THD_STACK_SIZE   32768
	Default thread stack size.
#define	THD_KERNEL_STACK_SIZE   (64 * 1024)
	Main/kernel thread's stack size.

Functions
static __always_inline uintptr_t	arch_get_ret_addr (void)
	DC specific "function" to get the return address from the current function.
static __always_inline uintptr_t	arch_get_fptr (void)
	DC specific "function" to get the frame pointer from the current function.
static uintptr_t	arch_fptr_ret_addr (uintptr_t fptr)
	Pass in a frame pointer value to get the return address for the given frame.
static uintptr_t	arch_fptr_next (uintptr_t fptr)
	Pass in a frame pointer value to get the previous frame pointer for the given frame.
bool	arch_stk_unwind_step (uintptr_t sp, uintptr_t *ret_addr_out, uintptr_t *next_sp_out)
	Find the next return address by scanning the stack.
void	arch_stk_setup (kthread_t *nt)
	Set up new stack before running.
void	arch_stk_trace (int n)
	Do a stack trace from the current function.
void	arch_stk_trace_at (uintptr_t sp, size_t n)
	Do a stack trace from the given stack pointer.

Detailed Description

API for managing stack backtracing

Macro Definition Documentation

THD_KERNEL_STACK_SIZE

#define THD_KERNEL_STACK_SIZE   (64 * 1024)

Main/kernel thread's stack size.

THD_STACK_ALIGNMENT

#define THD_STACK_ALIGNMENT   8

Required alignment for stack.

THD_STACK_SIZE

#define THD_STACK_SIZE   32768

Default thread stack size.

Function Documentation

arch_fptr_next()

static uintptr_t arch_fptr_next ( uintptr_t fptr )

inlinestatic

Pass in a frame pointer value to get the previous frame pointer for the given frame.

Parameters

fptr	The frame pointer to look at.

Returns

The previous frame pointer.

References arch_fptr_ret_addr().

arch_fptr_ret_addr()

static uintptr_t arch_fptr_ret_addr ( uintptr_t fptr )

inlinestatic

Pass in a frame pointer value to get the return address for the given frame.

Parameters

fptr	The frame pointer to look at.

Returns

The return address of the pointer.

Referenced by arch_fptr_next().

arch_get_fptr()

static __always_inline uintptr_t arch_get_fptr ( void )

static

DC specific "function" to get the frame pointer from the current function.

Returns

The frame pointer from the current function.

Note

This only works if you don't disable frame pointers.

arch_get_ret_addr()

static __always_inline uintptr_t arch_get_ret_addr ( void )

static

DC specific "function" to get the return address from the current function.

Returns

The return address of the current function.

Referenced by __stack_chk_fail().

arch_stk_setup()

void arch_stk_setup

(

kthread_t *

nt

)

Set up new stack before running.

This function does nothing as it is unnecessary on Dreamcast.

Parameters

nt	A pointer to the new thread for which a stack is to be set up.

arch_stk_trace()

void arch_stk_trace

(

int

n

)

Do a stack trace from the current function.

This function does a stack trace from the current function, printing the results to stdout. This is used, for instance, when an assertion fails in assert().

Parameters

n	The number of frames to leave off. Each frame is a jump to subroutine or branch to subroutine. assert() leaves off 2 frames, for reference.

See also

arch_stk_trace_at

Referenced by depth_recurse(), do_work(), and main().

arch_stk_trace_at()

void arch_stk_trace_at	(	uintptr_t	sp,
		size_t	n )

Do a stack trace from the given stack pointer.

This function does a stack trace from the specified stack pointer, printing the results to stdout. This could be used for doing something like stack tracing a main thread from inside an IRQ handler.

Parameters

sp	The stack pointer to start scanning from.
n	The number of frames to leave off.

arch_stk_unwind_step()

bool arch_stk_unwind_step	(	uintptr_t	sp,
		uintptr_t *	ret_addr_out,
		uintptr_t *	next_sp_out )

Find the next return address by scanning the stack.

Scans upward from the given stack pointer for saved PR values validated as return addresses from call instructions.

Parameters

sp	Stack pointer to start scanning from.
ret_addr_out	On success, receives the found return address.
next_sp_out	On success, receives the stack position to continue scanning from.

Returns

true if a return address was found.