Merge branch 'master'

3 files changed, 41 insertions, 31 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index 4897977a1f4b..3b25b182d2be 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -825,6 +825,14 @@ fastcall NORET_TYPE void do_exit(long code)
 
         tsk->flags |= PF_EXITING;
 
+        /*
+         * Make sure we don't try to process any timer firings
+         * while we are already exiting.
+         */
+        tsk->it_virt_expires = cputime_zero;
+        tsk->it_prof_expires = cputime_zero;
+        tsk->it_sched_expires = 0;
+
         if (unlikely(in_atomic()))
                 printk(KERN_INFO "note: %s[%d] exited with preempt_count %d\n",
                                 current->comm, current->pid,
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index b15462b17a58..bf374fceb39c 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -91,7 +91,7 @@ static inline union cpu_time_count cpu_time_sub(clockid_t which_clock,
  * Update expiry time from increment, and increase overrun count,
  * given the current clock sample.
  */
-static inline void bump_cpu_timer(struct k_itimer *timer,
+static void bump_cpu_timer(struct k_itimer *timer,
                                   union cpu_time_count now)
 {
         int i;
@@ -110,7 +110,7 @@ static inline void bump_cpu_timer(struct k_itimer *timer,
                 for (i = 0; incr < delta - incr; i++)
                         incr = incr << 1;
                 for (; i >= 0; incr >>= 1, i--) {
-                        if (delta <= incr)
+                        if (delta < incr)
                                 continue;
                         timer->it.cpu.expires.sched += incr;
                         timer->it_overrun += 1 << i;
@@ -128,7 +128,7 @@ static inline void bump_cpu_timer(struct k_itimer *timer,
                 for (i = 0; cputime_lt(incr, cputime_sub(delta, incr)); i++)
                              incr = cputime_add(incr, incr);
                 for (; i >= 0; incr = cputime_halve(incr), i--) {
-                        if (cputime_le(delta, incr))
+                        if (cputime_lt(delta, incr))
                                 continue;
                         timer->it.cpu.expires.cpu =
                                 cputime_add(timer->it.cpu.expires.cpu, incr);
@@ -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);
@@ -576,17 +579,15 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now)
         listpos = head;
         if (CPUCLOCK_WHICH(timer->it_clock) == CPUCLOCK_SCHED) {
                 list_for_each_entry(next, head, entry) {
-                        if (next->expires.sched > nt->expires.sched) {
-                                listpos = &next->entry;
+                        if (next->expires.sched > nt->expires.sched)
                                 break;
-                        }
+                        listpos = &next->entry;
                 }
         } else {
                 list_for_each_entry(next, head, entry) {
-                        if (cputime_gt(next->expires.cpu, nt->expires.cpu)) {
-                                listpos = &next->entry;
+                        if (cputime_gt(next->expires.cpu, nt->expires.cpu))
                                 break;
-                        }
+                        listpos = &next->entry;
                 }
         }
         list_add(&nt->entry, listpos);
@@ -1206,7 +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);
         }
 }
@@ -1295,30 +1296,30 @@ void run_posix_cpu_timers(struct task_struct *tsk)
 
 #undef  UNEXPIRED
 
+        BUG_ON(tsk->exit_state);
+
         /*
          * Double-check with locks held.
          */
         read_lock(&tasklist_lock);
-        if (likely(tsk->signal != NULL)) {
-                spin_lock(&tsk->sighand->siglock);
+        spin_lock(&tsk->sighand->siglock);
 
-                /*
-                 * Here we take off tsk->cpu_timers[N] and tsk->signal->cpu_timers[N]
-                 * all the timers that are firing, and put them on the firing list.
-                 */
-                check_thread_timers(tsk, &firing);
-                check_process_timers(tsk, &firing);
+        /*
+         * Here we take off tsk->cpu_timers[N] and tsk->signal->cpu_timers[N]
+         * all the timers that are firing, and put them on the firing list.
+         */
+        check_thread_timers(tsk, &firing);
+        check_process_timers(tsk, &firing);
 
-                /*
-                 * We must release these locks before taking any timer's lock.
-                 * There is a potential race with timer deletion here, as the
-                 * siglock now protects our private firing list.  We have set
-                 * the firing flag in each timer, so that a deletion attempt
-                 * that gets the timer lock before we do will give it up and
-                 * spin until we've taken care of that timer below.
-                 */
-                spin_unlock(&tsk->sighand->siglock);
-        }
+        /*
+         * We must release these locks before taking any timer's lock.
+         * There is a potential race with timer deletion here, as the
+         * siglock now protects our private firing list.  We have set
+         * the firing flag in each timer, so that a deletion attempt
+         * that gets the timer lock before we do will give it up and
+         * spin until we've taken care of that timer below.
+         */
+        spin_unlock(&tsk->sighand->siglock);
         read_unlock(&tasklist_lock);
 
         /*
diff --git a/kernel/sched.c b/kernel/sched.c
index 1f31a528fdba..1e5cafdf4e27 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3879,6 +3879,7 @@ EXPORT_SYMBOL(cpu_present_map);
 
 #ifndef CONFIG_SMP
 cpumask_t cpu_online_map = CPU_MASK_ALL;
+EXPORT_SYMBOL_GPL(cpu_online_map);
 cpumask_t cpu_possible_map = CPU_MASK_ALL;
 #endif