Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  hrtimers: fix inconsistent lock state on resume in hres_timers_resume
  time-sched.c: tick_nohz_update_jiffies should be static
  locking, hpet: annotate false positive warning
  kernel/fork.c: unused variable 'ret'
  itimers: remove the per-cpu-ish-ness

9 files changed, 57 insertions, 111 deletions

diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index cd759ad90690..bb2e0f0975ae 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -628,7 +628,7 @@ static int hpet_cpuhp_notify(struct notifier_block *n,
 
         switch (action & 0xf) {
         case CPU_ONLINE:
-                INIT_DELAYED_WORK(&work.work, hpet_work);
+                INIT_DELAYED_WORK_ON_STACK(&work.work, hpet_work);
                 init_completion(&work.complete);
                 /* FIXME: add schedule_work_on() */
                 schedule_delayed_work_on(cpu, &work.work, 0);
diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index 2f3c2d4ef73b..ea0ea1a4c36f 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -48,6 +48,12 @@ extern struct fs_struct init_fs;
         .posix_timers    = LIST_HEAD_INIT(sig.posix_timers),            \
         .cpu_timers     = INIT_CPU_TIMERS(sig.cpu_timers),              \
         .rlim           = INIT_RLIMITS,                                 \
+        .cputime        = { .totals = {                                 \
+                .utime = cputime_zero,                                  \
+                .stime = cputime_zero,                                  \
+                .sum_exec_runtime = 0,                                  \
+                .lock = __SPIN_LOCK_UNLOCKED(sig.cputime.totals.lock),  \
+        }, },                                                           \
 }
 
 extern struct nsproxy init_nsproxy;
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 4cae9b81a1f8..c20943eabb4c 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -450,6 +450,7 @@ struct task_cputime {
         cputime_t utime;
         cputime_t stime;
         unsigned long long sum_exec_runtime;
+        spinlock_t lock;
 };
 /* Alternate field names when used to cache expirations. */
 #define prof_exp        stime
@@ -465,7 +466,7 @@ struct task_cputime {
  * used for thread group CPU clock calculations.
  */
 struct thread_group_cputime {
-        struct task_cputime *totals;
+        struct task_cputime totals;
 };
 
 /*
@@ -2180,24 +2181,30 @@ static inline int spin_needbreak(spinlock_t *lock)
  * Thread group CPU time accounting.
  */
 
-extern int thread_group_cputime_alloc(struct task_struct *);
-extern void thread_group_cputime(struct task_struct *, struct task_cputime *);
-
-static inline void thread_group_cputime_init(struct signal_struct *sig)
+static inline
+void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
 {
-        sig->cputime.totals = NULL;
+        struct task_cputime *totals = &tsk->signal->cputime.totals;
+        unsigned long flags;
+
+        spin_lock_irqsave(&totals->lock, flags);
+        *times = *totals;
+        spin_unlock_irqrestore(&totals->lock, flags);
 }
 
-static inline int thread_group_cputime_clone_thread(struct task_struct *curr)
+static inline void thread_group_cputime_init(struct signal_struct *sig)
 {
-        if (curr->signal->cputime.totals)
-                return 0;
-        return thread_group_cputime_alloc(curr);
+        sig->cputime.totals = (struct task_cputime){
+                .utime = cputime_zero,
+                .stime = cputime_zero,
+                .sum_exec_runtime = 0,
+        };
+
+        spin_lock_init(&sig->cputime.totals.lock);
 }
 
 static inline void thread_group_cputime_free(struct signal_struct *sig)
 {
-        free_percpu(sig->cputime.totals);
 }
 
 /*
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index b36291130f22..47151c8495aa 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -118,6 +118,12 @@ struct execute_work {
                 init_timer(&(_work)->timer);                    \
         } while (0)
 
+#define INIT_DELAYED_WORK_ON_STACK(_work, _func)                \
+        do {                                                    \
+                INIT_WORK(&(_work)->work, (_func));             \
+                init_timer_on_stack(&(_work)->timer);           \
+        } while (0)
+
 #define INIT_DELAYED_WORK_DEFERRABLE(_work, _func)                      \
         do {                                                    \
                 INIT_WORK(&(_work)->work, (_func));             \
diff --git a/kernel/fork.c b/kernel/fork.c
index bf0cef8bbdf2..242a706e7721 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -817,17 +817,17 @@ static void posix_cpu_timers_init_group(struct signal_struct *sig)
 static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
 {
         struct signal_struct *sig;
-        int ret;
 
         if (clone_flags & CLONE_THREAD) {
-                ret = thread_group_cputime_clone_thread(current);
-                if (likely(!ret)) {
-                        atomic_inc(&current->signal->count);
-                        atomic_inc(&current->signal->live);
-                }
-                return ret;
+                atomic_inc(&current->signal->count);
+                atomic_inc(&current->signal->live);
+                return 0;
         }
         sig = kmem_cache_alloc(signal_cachep, GFP_KERNEL);
+
+        if (sig)
+                posix_cpu_timers_init_group(sig);
+
         tsk->signal = sig;
         if (!sig)
                 return -ENOMEM;
@@ -864,8 +864,6 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
         memcpy(sig->rlim, current->signal->rlim, sizeof sig->rlim);
         task_unlock(current->group_leader);
 
-        posix_cpu_timers_init_group(sig);
-
         acct_init_pacct(&sig->pacct);
 
         tty_audit_fork(sig);
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 2dc30c59c5fd..f33afb0407bc 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -614,7 +614,9 @@ void clock_was_set(void)
  */
 void hres_timers_resume(void)
 {
-        /* Retrigger the CPU local events: */
+        WARN_ONCE(!irqs_disabled(),
+                  KERN_INFO "hres_timers_resume() called with IRQs enabled!");
+
         retrigger_next_event(NULL);
 }
 
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index 157de3a47832..fa07da94d7be 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -10,76 +10,6 @@
 #include <linux/kernel_stat.h>
 
 /*
- * Allocate the thread_group_cputime structure appropriately and fill in the
- * current values of the fields.  Called from copy_signal() via
- * thread_group_cputime_clone_thread() when adding a second or subsequent