Classes
struct	modm_context_t
	The fiber context stores information about the stack More...

Functions
void	modm_context_init (modm_context_t ctx, uintptr_t bottom, uintptr_t *top, uintptr_t fn, uintptr_t arg)

void	modm_context_reset (modm_context_t *ctx)

uintptr_t	modm_context_start (modm_context_t *to)

void	modm_context_jump (modm_context_t from, modm_context_t to)

void modm_noreturn	modm_context_end (uintptr_t retval)

void	modm_context_stack_watermark (modm_context_t *ctx)

size_t	modm_context_stack_usage (const modm_context_t *ctx)

Detailed Description

These functions implement the underlying architecture specific operations to initialize, start, yield, and end fibers. These can be used to implement an alternative scheduling strategy or use fibers outside of modm.

Function Documentation

void modm_noreturn modm_context_end ( uintptr_t retval )

Switches control from the fiber context back to the main context. Control flow then continues in the main context by returning from the modm_context_start() function.

void modm_context_init	(	modm_context_t *	ctx,
		uintptr_t *	bottom,
		uintptr_t *	top,
		uintptr_t	fn,
		uintptr_t	arg
	)

Initializes the context with the function pointer and argument stored at the top. The ctx->sp is set to two uintptr_t below the top. Must be called only once to initialize the stack.

Parameters

fn	function pointer to a `void(*)(uintptr_t)` function.

void modm_context_jump	(	modm_context_t *	from,
		modm_context_t *	to
	)

Pushes the context onto the from->sp and pops the context from the to->sp to jump from one fiber to the next.

void modm_context_reset ( modm_context_t * ctx )

Resets the context stack pointer to the correct offset in preparation for jumping into the fiber. Must be called after initialization, but every time the function is started from the beginning.

size_t modm_context_stack_usage ( const modm_context_t * ctx )

Returns the stack usage by searching from the bottom of the stack for the watermark level. You may call this function at any point after calling modm_context_stack_watermark().

void modm_context_stack_watermark ( modm_context_t * ctx )

Zeros the register file and watermarks the rest of the stack. You may call this function before or after modm_context_reset(), however, NOT while the fiber is running!

uintptr_t modm_context_start ( modm_context_t * to )

Switches control from the main context to the fiber context. This initializes the hardware and then jumps from the caller context into the to fiber.

Classes

Functions

Detailed Description

Function Documentation