Inter-component Interfaces: HyThread Struct Reference


Public Attributes
void *	reserved
uint32	request
	Number of requests made for this thread, it includes both suspend requests and safe point callback requests.
int16	disable_count
	Field indicating that thread can safely be suspended.
hythread_group_t	group
	Group for this thread.
void *	thread_local_storage [10]
	Array representing thread local storage.
hythread_library_t	library
	Each thread keeps a pointer to the library it belongs to.
uint32	suspend_count
	Number of suspend requests made for this thread.
hythread_event_callback_proc	safepoint_callback
	Function to be executed at safepoint upon thread resume.
hysem_t	resume_event
	Event used to notify suspended thread that it needs to wake up.
hythread_t	next
	Points to the next thread within the group.
hythread_t	prev
	Points to the last thread within the group.
osthread_t	os_handle
	Handle to OS thread.
hymutex_t	mutex
	Thread local lock, used to serialize thread state;.
hythread_monitor_t	monitor
	Monitor used to implement wait function for sleep/park;.
hycond_t *	current_condition
	Current conditional variable thread is waiting on (used for interrupting).
IDATA	state
	Thread state.
int	priority
	Hint for scheduler about thread priority.
char	java_status
	Flag illustrates that java thread status.
char	need_to_free
	Release indicator.
UDATA	stacksize
	Size of thread's stack, set on creation.
uint32	interrupted
	Flag of interruption.
hythread_monitor_t	waited_monitor
	Monitor this thread is waiting on now.
IDATA	thread_id
	ID for this thread.

Member Data Documentation

void* HyThread.reserved

uint32 HyThread.request

Number of requests made for this thread, it includes both suspend requests and safe point callback requests.

The field is modified by atomic operations.

Increment in functions: 1. send_suspend_request()

sets suspend request for a given thread 2. hythread_set_safepoint_callback()
sets safe point callback request for a given thread

Decrement in functions: 1. hythread_resume()

removes suspend request for a given thread 2. hythread_exception_safe_point()
removes safe point callback request for current thread

int16 HyThread.disable_count

Field indicating that thread can safely be suspended.

Safe suspension is enabled on value 0.

The disable_count is increased/decreaded in hythread_suspend_disable()/hythread_suspend_enable() function for current thread only.

Also disable_count could be reset to value 0 and restored in hythread_set_suspend_disable()/hythread_set_suspend_disable() function for current thread only.

Function hythread_exception_safe_point() sets disable_count to value 1 before safe point callback function calling and restores it after the call.

Function thread_safe_point_impl() sets disable_count to value 0 before entering to the safe point and restores it after exitting.

hythread_group_t HyThread.group

Group for this thread.

Different groups are needed in order to be able to quickly iterate over the specific group. Examples are: Java threads, GC private threads. Equal to the address of the head of the list of threads for this group.

void* HyThread.thread_local_storage[10]

Array representing thread local storage.

hythread_library_t HyThread.library

Each thread keeps a pointer to the library it belongs to.

uint32 HyThread.suspend_count

Number of suspend requests made for this thread.

The field is modified by atomic operations.

After increment/decrement of suspend_count, request field should be incremented/decremented too.

hythread_event_callback_proc HyThread.safepoint_callback

Function to be executed at safepoint upon thread resume.

Field is set in hythread_set_safepoint_callback() function and reset hythread_exception_safe_point() function.

After set/reset of safepoint_callback, request field should be incremented/decremented too.