signal: sys_rt_sigtimedwait: simplify the timeout logic

No functional changes, cleanup compat_sys_rt_sigtimedwait() and
sys_rt_sigtimedwait().

Calculate the timeout before we take ->siglock, this simplifies and
lessens the code. Use timespec_valid() to check the timespec.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Matt Fleming <matt.fleming@linux.intel.com>
This commit is contained in:
Oleg Nesterov 2011-04-27 21:24:19 +02:00
parent bb7efee2ca
commit fe0faa005d
2 changed files with 36 additions and 48 deletions

View File

@ -893,7 +893,7 @@ compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
int sig;
struct timespec t;
siginfo_t info;
long ret, timeout = 0;
long ret, timeout;
if (sigsetsize != sizeof(sigset_t))
return -EINVAL;
@ -904,36 +904,30 @@ compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
sigdelsetmask(&s,sigmask(SIGKILL)|sigmask(SIGSTOP));
signotset(&s);
timeout = MAX_SCHEDULE_TIMEOUT;
if (uts) {
if (get_compat_timespec (&t, uts))
return -EFAULT;
if (t.tv_nsec >= 1000000000L || t.tv_nsec < 0
|| t.tv_sec < 0)
if (!timespec_valid(&t))
return -EINVAL;
timeout = timespec_to_jiffies(&t) + (t.tv_sec || t.tv_nsec);
}
spin_lock_irq(&current->sighand->siglock);
sig = dequeue_signal(current, &s, &info);
if (!sig) {
timeout = MAX_SCHEDULE_TIMEOUT;
if (uts)
timeout = timespec_to_jiffies(&t)
+(t.tv_sec || t.tv_nsec);
if (timeout) {
current->real_blocked = current->blocked;
sigandsets(&current->blocked, &current->blocked, &s);
if (!sig && timeout) {
current->real_blocked = current->blocked;
sigandsets(&current->blocked, &current->blocked, &s);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
timeout = schedule_timeout_interruptible(timeout);
timeout = schedule_timeout_interruptible(timeout);
spin_lock_irq(&current->sighand->siglock);
sig = dequeue_signal(current, &s, &info);
current->blocked = current->real_blocked;
siginitset(&current->real_blocked, 0);
recalc_sigpending();
}
spin_lock_irq(&current->sighand->siglock);
sig = dequeue_signal(current, &s, &info);
current->blocked = current->real_blocked;
siginitset(&current->real_blocked, 0);
recalc_sigpending();
}
spin_unlock_irq(&current->sighand->siglock);
@ -943,7 +937,7 @@ compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
if (copy_siginfo_to_user32(uinfo, &info))
ret = -EFAULT;
}
}else {
} else {
ret = timeout?-EINTR:-EAGAIN;
}
return ret;

View File

@ -2519,7 +2519,7 @@ SYSCALL_DEFINE4(rt_sigtimedwait, const sigset_t __user *, uthese,
sigset_t these;
struct timespec ts;
siginfo_t info;
long timeout = 0;
long timeout;
/* XXX: Don't preclude handling different sized sigset_t's. */
if (sigsetsize != sizeof(sigset_t))
@ -2535,41 +2535,35 @@ SYSCALL_DEFINE4(rt_sigtimedwait, const sigset_t __user *, uthese,
sigdelsetmask(&these, sigmask(SIGKILL)|sigmask(SIGSTOP));
signotset(&these);
timeout = MAX_SCHEDULE_TIMEOUT;
if (uts) {
if (copy_from_user(&ts, uts, sizeof(ts)))
return -EFAULT;
if (ts.tv_nsec >= 1000000000L || ts.tv_nsec < 0
|| ts.tv_sec < 0)
if (!timespec_valid(&ts))
return -EINVAL;
timeout = timespec_to_jiffies(&ts) + (ts.tv_sec || ts.tv_nsec);
}
spin_lock_irq(&current->sighand->siglock);
sig = dequeue_signal(current, &these, &info);
if (!sig) {
timeout = MAX_SCHEDULE_TIMEOUT;
if (uts)
timeout = (timespec_to_jiffies(&ts)
+ (ts.tv_sec || ts.tv_nsec));
if (!sig && timeout) {
/*
* None ready -- temporarily unblock those we're
* interested while we are sleeping in so that we'll
* be awakened when they arrive.
*/
current->real_blocked = current->blocked;
sigandsets(&current->blocked, &current->blocked, &these);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
if (timeout) {
/*
* None ready -- temporarily unblock those we're
* interested while we are sleeping in so that we'll
* be awakened when they arrive.
*/
current->real_blocked = current->blocked;
sigandsets(&current->blocked, &current->blocked, &these);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
timeout = schedule_timeout_interruptible(timeout);
timeout = schedule_timeout_interruptible(timeout);
spin_lock_irq(&current->sighand->siglock);
sig = dequeue_signal(current, &these, &info);
current->blocked = current->real_blocked;
siginitset(&current->real_blocked, 0);
recalc_sigpending();
}
spin_lock_irq(&current->sighand->siglock);
sig = dequeue_signal(current, &these, &info);
current->blocked = current->real_blocked;
siginitset(&current->real_blocked, 0);
recalc_sigpending();
}
spin_unlock_irq(&current->sighand->siglock);