[PATCH] Yet more posix-cpu-timer fixes

This just makes sure that a thread's expiry times can't get reset after
it clears them in do_exit.

This is what allowed us to re-introduce the stricter BUG_ON() check in
a362f463a6d316d14daed0f817e151835ce97ff7.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index ea1aca5..bf374fc 100644 (file)
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -497,7 +497,7 @@ static void process_timer_rebalance(struct task_struct *p,
                left = cputime_div(cputime_sub(expires.cpu, val.cpu),
                                   nthreads);
                do {
-                       if (!unlikely(t->exit_state)) {
+                       if (!unlikely(t->flags & PF_EXITING)) {
                                ticks = cputime_add(prof_ticks(t), left);
                                if (cputime_eq(t->it_prof_expires,
                                               cputime_zero) ||
@@ -512,7 +512,7 @@ static void process_timer_rebalance(struct task_struct *p,
                left = cputime_div(cputime_sub(expires.cpu, val.cpu),
                                   nthreads);
                do {
-                       if (!unlikely(t->exit_state)) {
+                       if (!unlikely(t->flags & PF_EXITING)) {
                                ticks = cputime_add(virt_ticks(t), left);
                                if (cputime_eq(t->it_virt_expires,
                                               cputime_zero) ||
@@ -527,7 +527,7 @@ static void process_timer_rebalance(struct task_struct *p,
                nsleft = expires.sched - val.sched;
                do_div(nsleft, nthreads);
                do {
-                       if (!unlikely(t->exit_state)) {
+                       if (!unlikely(t->flags & PF_EXITING)) {
                                ns = t->sched_time + nsleft;
                                if (t->it_sched_expires == 0 ||
                                    t->it_sched_expires > ns) {
@@ -566,6 +566,9 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now)
        struct cpu_timer_list *next;
        unsigned long i;
 
+       if (CPUCLOCK_PERTHREAD(timer->it_clock) && (p->flags & PF_EXITING))
+               return;
+
        head = (CPUCLOCK_PERTHREAD(timer->it_clock) ?
                p->cpu_timers : p->signal->cpu_timers);
        head += CPUCLOCK_WHICH(timer->it_clock);
@@ -1204,7 +1207,7 @@ static void check_process_timers(struct task_struct *tsk,
 
                        do {
                                t = next_thread(t);
-                       } while (unlikely(t->exit_state));
+                       } while (unlikely(t->flags & PF_EXITING));
                } while (t != tsk);
        }
 }