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Ignore whitespace Rev 3473 → Rev 3474

/branches/dynload/kernel/generic/src/udebug/udebug.c
32,8 → 32,10
 
/**
* @file
* @brief Udebug.
* @brief Udebug hooks and data structure management.
*
* Udebug is an interface that makes userspace debuggers possible.
*
* Functions in this file are executed directly in each thread, which
* may or may not be the subject of debugging. The udebug_stoppable_begin/end()
* functions are also executed in the clock interrupt handler. To avoid
63,6 → 65,11
atomic_dec(&THREAD->udebug.int_lock);
}
 
/** Initialize udebug part of task structure.
*
* Called as part of task structure initialization.
* @param ut Pointer to the structure to initialize.
*/
void udebug_task_init(udebug_task_t *ut)
{
mutex_initialize(&ut->lock, MUTEX_PASSIVE);
72,6 → 79,11
ut->evmask = 0;
}
 
/** Initialize udebug part of thread structure.
*
* Called as part of thread structure initialization.
* @param ut Pointer to the structure to initialize.
*/
void udebug_thread_initialize(udebug_thread_t *ut)
{
mutex_initialize(&ut->lock, MUTEX_PASSIVE);
89,6 → 101,14
ut->cur_event = 0; /* none */
}
 
/** Wait for a GO message.
*
* When a debugging event occurs in a thread or the thread is stopped,
* this function is called to block the thread until a GO message
* is received.
*
* @param wq The wait queue used by the thread to wait for GO messages.
*/
static void udebug_wait_for_go(waitq_t *wq)
{
int rc;
104,10 → 124,13
 
/** Do a preliminary check that a debugging session is in progress.
*
* This only requires the THREAD->udebug.lock mutex (and not
* TASK->udebug.lock mutex). For an undebugged task, this will
* never block (while there could be collisions by different threads
* on the TASK mutex), thus improving SMP perormance for undebugged tasks.
* This only requires the THREAD->udebug.lock mutex (and not TASK->udebug.lock
* mutex). For an undebugged task, this will never block (while there could be
* collisions by different threads on the TASK mutex), thus improving SMP
* perormance for undebugged tasks.
*
* @return True if the thread was in a debugging session when the function
* checked, false otherwise.
*/
static bool udebug_thread_precheck(void)
{
120,6 → 143,16
return res;
}
 
/** Start of stoppable section.
*
* A stoppable section is a section of code where if the thread can be stoped. In other words,
* if a STOP operation is issued, the thread is guaranteed not to execute
* any userspace instructions until the thread is resumed.
*
* Having stoppable sections is better than having stopping points, since
* a thread can be stopped even when it is blocked indefinitely in a system
* call (whereas it would not reach any stopping point).
*/
void udebug_stoppable_begin(void)
{
int nsc;
188,6 → 221,11
mutex_unlock(&TASK->udebug.lock);
}
 
/** End of a stoppable section.
*
* This is the point where the thread will block if it is stopped.
* (As, by definition, a stopped thread must not leave its stoppable section).
*/
void udebug_stoppable_end(void)
{
/* Early check for undebugged tasks */
258,6 → 296,11
udebug_int_unlock();
}
 
/** Syscall event hook.
*
* Must be called before and after servicing a system call. This generates
* a SYSCALL_B or SYSCALL_E event, depending on the value of @a end_variant.
*/
void udebug_syscall_event(unative_t a1, unative_t a2, unative_t a3,
unative_t a4, unative_t a5, unative_t a6, unative_t id, unative_t rc,
bool end_variant)
322,6 → 365,14
udebug_int_unlock();
}
 
/** Thread-creation event hook.
*
* Must be called when a new userspace thread is created in the debugged
* task. Generates a THREAD_B event.
*
* @param t Structure of the thread being created. Not locked, as the
* thread is not executing yet.
*/
void udebug_thread_b_event(struct thread *t)
{
call_t *call;
371,6 → 422,11
udebug_int_unlock();
}
 
/** Thread-termination event hook.
*
* Must be called when the current thread is terminating.
* Generates a THREAD_E event.
*/
void udebug_thread_e_event(void)
{
call_t *call;
417,8 → 473,12
/**
* Terminate task debugging session.
*
* \param ta->udebug.lock must be already locked.
* \return Zero on success or negative error code.
* Gracefully terminates the debugging session for a task. If the debugger
* is still waiting for events on some threads, it will receive a
* FINISHED event for each of them.
*
* @param ta Task structure. ta->udebug.lock must be already locked.
* @return Zero on success or negative error code.
*/
int udebug_task_cleanup(struct task *ta)
{
469,7 → 529,8
/* Answer GO call */
LOG("answer GO call with EVENT_FINISHED\n");
IPC_SET_RETVAL(t->udebug.go_call->data, 0);
IPC_SET_ARG1(t->udebug.go_call->data, UDEBUG_EVENT_FINISHED);
IPC_SET_ARG1(t->udebug.go_call->data,
UDEBUG_EVENT_FINISHED);
 
ipc_answer(&ta->answerbox, t->udebug.go_call);
t->udebug.go_call = NULL;