#include <linux/interrupt.h>
#include <linux/syscalls.h>
#include <linux/time.h>
+#include <linux/posix-timers.h>
#include <asm/uaccess.h>
+static unsigned long it_real_value(struct signal_struct *sig)
+{
+ unsigned long val = 0;
+ if (timer_pending(&sig->real_timer)) {
+ val = sig->real_timer.expires - jiffies;
+
+ /* look out for negative/zero itimer.. */
+ if ((long) val <= 0)
+ val = 1;
+ }
+ return val;
+}
+
int do_getitimer(int which, struct itimerval *value)
{
- register unsigned long val;
+ struct task_struct *tsk = current;
+ unsigned long interval, val;
+ cputime_t cinterval, cval;
switch (which) {
case ITIMER_REAL:
- val = 0;
- /*
- * FIXME! This needs to be atomic, in case the kernel timer happens!
- */
- if (timer_pending(¤t->real_timer)) {
- val = current->real_timer.expires - jiffies;
-
- /* look out for negative/zero itimer.. */
- if ((long) val <= 0)
- val = 1;
- }
+ spin_lock_irq(&tsk->sighand->siglock);
+ interval = tsk->signal->it_real_incr;
+ val = it_real_value(tsk->signal);
+ spin_unlock_irq(&tsk->sighand->siglock);
jiffies_to_timeval(val, &value->it_value);
- jiffies_to_timeval(current->it_real_incr, &value->it_interval);
+ jiffies_to_timeval(interval, &value->it_interval);
break;
case ITIMER_VIRTUAL:
- cputime_to_timeval(current->it_virt_value, &value->it_value);
- cputime_to_timeval(current->it_virt_incr, &value->it_interval);
+ read_lock(&tasklist_lock);
+ spin_lock_irq(&tsk->sighand->siglock);
+ cval = tsk->signal->it_virt_expires;
+ cinterval = tsk->signal->it_virt_incr;
+ if (!cputime_eq(cval, cputime_zero)) {
+ struct task_struct *t = tsk;
+ cputime_t utime = tsk->signal->utime;
+ do {
+ utime = cputime_add(utime, t->utime);
+ t = next_thread(t);
+ } while (t != tsk);
+ if (cputime_le(cval, utime)) { /* about to fire */
+ cval = jiffies_to_cputime(1);
+ } else {
+ cval = cputime_sub(cval, utime);
+ }
+ }
+ spin_unlock_irq(&tsk->sighand->siglock);
+ read_unlock(&tasklist_lock);
+ cputime_to_timeval(cval, &value->it_value);
+ cputime_to_timeval(cinterval, &value->it_interval);
break;
case ITIMER_PROF:
- cputime_to_timeval(current->it_prof_value, &value->it_value);
- cputime_to_timeval(current->it_prof_incr, &value->it_interval);
+ read_lock(&tasklist_lock);
+ spin_lock_irq(&tsk->sighand->siglock);
+ cval = tsk->signal->it_prof_expires;
+ cinterval = tsk->signal->it_prof_incr;
+ if (!cputime_eq(cval, cputime_zero)) {
+ struct task_struct *t = tsk;
+ cputime_t ptime = cputime_add(tsk->signal->utime,
+ tsk->signal->stime);
+ do {
+ ptime = cputime_add(ptime,
+ cputime_add(t->utime,
+ t->stime));
+ t = next_thread(t);
+ } while (t != tsk);
+ if (cputime_le(cval, ptime)) { /* about to fire */
+ cval = jiffies_to_cputime(1);
+ } else {
+ cval = cputime_sub(cval, ptime);
+ }
+ }
+ spin_unlock_irq(&tsk->sighand->siglock);
+ read_unlock(&tasklist_lock);
+ cputime_to_timeval(cval, &value->it_value);
+ cputime_to_timeval(cinterval, &value->it_interval);
break;
default:
return(-EINVAL);
return 0;
}
-/* SMP: Only we modify our itimer values. */
asmlinkage long sys_getitimer(int which, struct itimerval __user *value)
{
int error = -EFAULT;
return error;
}
+/*
+ * Called with P->sighand->siglock held and P->signal->real_timer inactive.
+ * If interval is nonzero, arm the timer for interval ticks from now.
+ */
+static inline void it_real_arm(struct task_struct *p, unsigned long interval)
+{
+ p->signal->it_real_value = interval; /* XXX unnecessary field?? */
+ if (interval == 0)
+ return;
+ if (interval > (unsigned long) LONG_MAX)
+ interval = LONG_MAX;
+ /* the "+ 1" below makes sure that the timer doesn't go off before
+ * the interval requested. This could happen if
+ * time requested % (usecs per jiffy) is more than the usecs left
+ * in the current jiffy */
+ p->signal->real_timer.expires = jiffies + interval + 1;
+ add_timer(&p->signal->real_timer);
+}
+
void it_real_fn(unsigned long __data)
{
struct task_struct * p = (struct task_struct *) __data;
- unsigned long interval;
send_group_sig_info(SIGALRM, SEND_SIG_PRIV, p);
- interval = p->it_real_incr;
- if (interval) {
- if (interval > (unsigned long) LONG_MAX)
- interval = LONG_MAX;
- p->real_timer.expires = jiffies + interval;
- add_timer(&p->real_timer);
- }
+
+ /*
+ * Now restart the timer if necessary. We don't need any locking
+ * here because do_setitimer makes sure we have finished running
+ * before it touches anything.
+ */
+ it_real_arm(p, p->signal->it_real_incr);
}
int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue)
{
- unsigned long expire;
- cputime_t cputime;
- int k;
+ struct task_struct *tsk = current;
+ unsigned long val, interval;
+ cputime_t cval, cinterval, nval, ninterval;
- if (ovalue && (k = do_getitimer(which, ovalue)) < 0)
- return k;
switch (which) {
- case ITIMER_REAL:
- del_timer_sync(¤t->real_timer);
- expire = timeval_to_jiffies(&value->it_value);
- current->it_real_value = expire;
- current->it_real_incr =
- timeval_to_jiffies(&value->it_interval);
- if (!expire)
- break;
- if (expire > (unsigned long) LONG_MAX)
- expire = LONG_MAX;
- current->real_timer.expires = jiffies + expire;
- add_timer(¤t->real_timer);
- break;
- case ITIMER_VIRTUAL:
- cputime = timeval_to_cputime(&value->it_value);
- if (cputime_gt(cputime, cputime_zero))
- cputime = cputime_add(cputime,
- jiffies_to_cputime(1));
- current->it_virt_value = cputime;
- cputime = timeval_to_cputime(&value->it_interval);
- current->it_virt_incr = cputime;
- break;
- case ITIMER_PROF:
- cputime = timeval_to_cputime(&value->it_value);
- if (cputime_gt(cputime, cputime_zero))
- cputime = cputime_add(cputime,
- jiffies_to_cputime(1));
- current->it_prof_value = cputime;
- cputime = timeval_to_cputime(&value->it_interval);
- current->it_prof_incr = cputime;
- break;
- default:
- return -EINVAL;
+ case ITIMER_REAL:
+ spin_lock_irq(&tsk->sighand->siglock);
+ interval = tsk->signal->it_real_incr;
+ val = it_real_value(tsk->signal);
+ if (val)
+ del_timer_sync(&tsk->signal->real_timer);
+ tsk->signal->it_real_incr =
+ timeval_to_jiffies(&value->it_interval);
+ it_real_arm(tsk, timeval_to_jiffies(&value->it_value));
+ spin_unlock_irq(&tsk->sighand->siglock);
+ if (ovalue) {
+ jiffies_to_timeval(val, &ovalue->it_value);
+ jiffies_to_timeval(interval,
+ &ovalue->it_interval);
+ }
+ break;
+ case ITIMER_VIRTUAL:
+ nval = timeval_to_cputime(&value->it_value);
+ ninterval = timeval_to_cputime(&value->it_interval);
+ read_lock(&tasklist_lock);
+ spin_lock_irq(&tsk->sighand->siglock);
+ cval = tsk->signal->it_virt_expires;
+ cinterval = tsk->signal->it_virt_incr;
+ if (!cputime_eq(cval, cputime_zero) ||
+ !cputime_eq(nval, cputime_zero)) {
+ if (cputime_gt(nval, cputime_zero))
+ nval = cputime_add(nval,
+ jiffies_to_cputime(1));
+ set_process_cpu_timer(tsk, CPUCLOCK_VIRT,
+ &nval, &cval);
+ }
+ tsk->signal->it_virt_expires = nval;
+ tsk->signal->it_virt_incr = ninterval;
+ spin_unlock_irq(&tsk->sighand->siglock);
+ read_unlock(&tasklist_lock);
+ if (ovalue) {
+ cputime_to_timeval(cval, &ovalue->it_value);
+ cputime_to_timeval(cinterval, &ovalue->it_interval);
+ }
+ break;
+ case ITIMER_PROF:
+ nval = timeval_to_cputime(&value->it_value);
+ ninterval = timeval_to_cputime(&value->it_interval);
+ read_lock(&tasklist_lock);
+ spin_lock_irq(&tsk->sighand->siglock);
+ cval = tsk->signal->it_prof_expires;
+ cinterval = tsk->signal->it_prof_incr;
+ if (!cputime_eq(cval, cputime_zero) ||
+ !cputime_eq(nval, cputime_zero)) {
+ if (cputime_gt(nval, cputime_zero))
+ nval = cputime_add(nval,
+ jiffies_to_cputime(1));
+ set_process_cpu_timer(tsk, CPUCLOCK_PROF,
+ &nval, &cval);
+ }
+ tsk->signal->it_prof_expires = nval;
+ tsk->signal->it_prof_incr = ninterval;
+ spin_unlock_irq(&tsk->sighand->siglock);
+ read_unlock(&tasklist_lock);
+ if (ovalue) {
+ cputime_to_timeval(cval, &ovalue->it_value);
+ cputime_to_timeval(cinterval, &ovalue->it_interval);
+ }
+ break;
+ default:
+ return -EINVAL;
}
return 0;
}
-/* SMP: Again, only we play with our itimers, and signals are SMP safe
- * now so that is not an issue at all anymore.
- */
asmlinkage long sys_setitimer(int which,
struct itimerval __user *value,
struct itimerval __user *ovalue)
git://git.onelab.eu / linux-2.6.git / blobdiff