diff options
| -rw-r--r-- | kernel/itimer.c | 37 |
1 files changed, 16 insertions, 21 deletions
diff --git a/kernel/itimer.c b/kernel/itimer.c index a72cb0e5aa4..7c1b25e25e4 100644 --- a/kernel/itimer.c +++ b/kernel/itimer.c @@ -112,28 +112,11 @@ asmlinkage long sys_getitimer(int which, struct itimerval __user *value) 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 inc = p->signal->it_real_incr; send_group_sig_info(SIGALRM, SEND_SIG_PRIV, p); @@ -141,14 +124,23 @@ void it_real_fn(unsigned long __data) * 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. + * Note, we KNOW we are (or should be) at a jiffie edge here so + * we don't need the +1 stuff. Also, we want to use the prior + * expire value so as to not "slip" a jiffie if we are late. + * Deal with requesting a time prior to "now" here rather than + * in add_timer. */ - it_real_arm(p, p->signal->it_real_incr); + if (!inc) + return; + while (time_before_eq(p->signal->real_timer.expires, jiffies)) + p->signal->real_timer.expires += inc; + add_timer(&p->signal->real_timer); } int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue) { struct task_struct *tsk = current; - unsigned long val, interval; + unsigned long val, interval, expires; cputime_t cval, cinterval, nval, ninterval; switch (which) { @@ -164,7 +156,10 @@ again: } tsk->signal->it_real_incr = timeval_to_jiffies(&value->it_interval); - it_real_arm(tsk, timeval_to_jiffies(&value->it_value)); + expires = timeval_to_jiffies(&value->it_value); + if (expires) + mod_timer(&tsk->signal->real_timer, + jiffies + 1 + expires); spin_unlock_irq(&tsk->sighand->siglock); if (ovalue) { jiffies_to_timeval(val, &ovalue->it_value); |