/*
* task_begin()
*
* Overview
* A process constructing a new task calls task_begin() to initialize the
* task, by attaching itself as a member.
*
* Return values
* None.
*
* Caller's context
* pidlock and p_lock must be held across the call to task_begin().
*/
void
task_begin(task_t *tk, proc_t *p)
{
timestruc_t ts;
task_usage_t *tu;
rctl_entity_p_t e;
ASSERT(MUTEX_HELD(&pidlock));
ASSERT(MUTEX_HELD(&p->p_lock));
mutex_enter(&tk->tk_usage_lock);
tu = tk->tk_usage;
gethrestime(&ts);
tu->tu_startsec = (uint64_t)ts.tv_sec;
tu->tu_startnsec = (uint64_t)ts.tv_nsec;
mutex_exit(&tk->tk_usage_lock);
/*
* Join process to the task as a member.
*/
task_attach(tk, p);
/*
* Now that the linkage from process to task is complete, do the
* required callback for the task rctl set.
*/
e.rcep_p.task = tk;
e.rcep_t = RCENTITY_TASK;
(void) rctl_set_dup(NULL, NULL, p, &e, tk->tk_rctls, NULL,
RCD_CALLBACK);
}
static struct snobj *handle_attach_task(struct snobj *q)
{
const char *m_name;
const char *tc_name;
task_id_t tid;
struct module *m;
struct task *t;
m_name = snobj_eval_str(q, "name");
if (!m_name)
return snobj_err(EINVAL, "Missing 'name' field");
if ((m = find_module(m_name)) == NULL)
return snobj_err(ENOENT, "No module '%s' found", m_name);
tid = snobj_eval_uint(q, "taskid");
if (tid >= MAX_TASKS_PER_MODULE)
return snobj_err(EINVAL, "'taskid' must be between 0 and %d",
MAX_TASKS_PER_MODULE - 1);
if ((t = m->tasks[tid]) == NULL)
return snobj_err(ENOENT, "Task %s:%hu does not exist",
m_name, tid);
tc_name = snobj_eval_str(q, "tc");
if (tc_name) {
struct tc *c;
c = ns_lookup(NS_TYPE_TC, tc_name);
if (!c)
return snobj_err(ENOENT, "No TC '%s' found", tc_name);
task_attach(t, c);
} else {
int wid; /* TODO: worker_id_t */
if (task_is_attached(t))
return snobj_err(EBUSY, "Task %s:%hu is already "
"attached to a TC", m_name, tid);
wid = snobj_eval_uint(q, "wid");
if (wid >= MAX_WORKERS)
return snobj_err(EINVAL, "'wid' must be between 0 and %d",
MAX_WORKERS - 1);
if (!is_worker_active(wid))
return snobj_err(EINVAL, "Worker %d does not exist", wid);
assign_default_tc(wid, t);
}
return NULL;
}