/*
* Clean out CPU timers still ticking when a thread exited. The task
* pointer is cleared, and the expiry time is replaced with the residual
* time for later timer_gettime calls to return.
* This must be called with the siglock held.
*/
static void cleanup_timers(struct list_head *head,
cputime_t utime, cputime_t stime,
unsigned long long sum_exec_runtime)
{
cputime_t ptime = utime + stime;
cleanup_timers_list(head, cputime_to_expires(ptime));
cleanup_timers_list(++head, cputime_to_expires(utime));
cleanup_timers_list(++head, sum_exec_runtime);
}
static inline unsigned long long virt_ticks(struct task_struct *p)
{
cputime_t utime, stime;
task_cputime(p, &utime, &stime);
return cputime_to_expires(utime);
}
/*
* Sample a process (thread group) timer for the given group_leader task.
* Must be called with task sighand lock held for safe while_each_thread()
* traversal.
*/
static int cpu_timer_sample_group(const clockid_t which_clock,
struct task_struct *p,
unsigned long long *sample)
{
struct task_cputime cputime;
thread_group_cputimer(p, &cputime);
switch (CPUCLOCK_WHICH(which_clock)) {
default:
return -EINVAL;
case CPUCLOCK_PROF:
*sample = cputime_to_expires(cputime.utime + cputime.stime);
break;
case CPUCLOCK_VIRT:
*sample = cputime_to_expires(cputime.utime);
break;
case CPUCLOCK_SCHED:
*sample = cputime.sum_exec_runtime;
break;
}
return 0;
}
static inline unsigned long long
timespec_to_sample(const clockid_t which_clock, const struct timespec *tp)
{
unsigned long long ret;
ret = 0; /* high half always zero when .cpu used */
if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) {
ret = (unsigned long long)tp->tv_sec * NSEC_PER_SEC + tp->tv_nsec;
} else {
ret = cputime_to_expires(timespec_to_cputime(tp));
}
return ret;
}