16 files changed, 228 insertions, 98 deletions

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 5a54ff42874e..e14db9c089b9 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2351,7 +2351,7 @@ static void cgroup_lock_hierarchy(struct cgroupfs_root *root)
         for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
                 struct cgroup_subsys *ss = subsys[i];
                 if (ss->root == root)
-                        mutex_lock_nested(&ss->hierarchy_mutex, i);
+                        mutex_lock(&ss->hierarchy_mutex);
         }
 }
 
@@ -2637,6 +2637,7 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss)
         BUG_ON(!list_empty(&init_task.tasks));
 
         mutex_init(&ss->hierarchy_mutex);
+        lockdep_set_class(&ss->hierarchy_mutex, &ss->subsys_key);
         ss->active = 1;
 }
 
diff --git a/kernel/exit.c b/kernel/exit.c
index f80dec3f1875..efd30ccf3858 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -118,6 +118,8 @@ static void __exit_signal(struct task_struct *tsk)
                  * We won't ever get here for the group leader, since it
                  * will have been the last reference on the signal_struct.
                  */
+                sig->utime = cputime_add(sig->utime, task_utime(tsk));
+                sig->stime = cputime_add(sig->stime, task_stime(tsk));
                 sig->gtime = cputime_add(sig->gtime, task_gtime(tsk));
                 sig->min_flt += tsk->min_flt;
                 sig->maj_flt += tsk->maj_flt;
@@ -126,6 +128,7 @@ static void __exit_signal(struct task_struct *tsk)
                 sig->inblock += task_io_get_inblock(tsk);
                 sig->oublock += task_io_get_oublock(tsk);
                 task_io_accounting_add(&sig->ioac, &tsk->ioac);
+                sig->sum_sched_runtime += tsk->se.sum_exec_runtime;
                 sig = NULL; /* Marker for below. */
         }
 
diff --git a/kernel/fork.c b/kernel/fork.c
index 6d5dbb7a13e2..a66fbde20715 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -851,13 +851,14 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
         sig->tty_old_pgrp = NULL;
         sig->tty = NULL;
 
-        sig->cutime = sig->cstime = cputime_zero;
+        sig->utime = sig->stime = sig->cutime = sig->cstime = cputime_zero;
         sig->gtime = cputime_zero;
         sig->cgtime = cputime_zero;
         sig->nvcsw = sig->nivcsw = sig->cnvcsw = sig->cnivcsw = 0;
         sig->min_flt = sig->maj_flt = sig->cmin_flt = sig->cmaj_flt = 0;
         sig->inblock = sig->oublock = sig->cinblock = sig->coublock = 0;
         task_io_accounting_init(&sig->ioac);
+        sig->sum_sched_runtime = 0;
         taskstats_tgid_init(sig);
 
         task_lock(current->group_leader);
@@ -1094,7 +1095,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 #ifdef CONFIG_DEBUG_MUTEXES
         p->blocked_on = NULL; /* not blocked yet */
 #endif
-        if (unlikely(ptrace_reparented(current)))
+        if (unlikely(current->ptrace))
                 ptrace_fork(p, clone_flags);
 
         /* Perform scheduler related setup. Assign this task to a CPU. */
diff --git a/kernel/itimer.c b/kernel/itimer.c
index 6a5fe93dd8bd..58762f7077ec 100644
--- a/kernel/itimer.c
+++ b/kernel/itimer.c
@@ -62,7 +62,7 @@ int do_getitimer(int which, struct itimerval *value)
                         struct task_cputime cputime;
                         cputime_t utime;
 
-                        thread_group_cputime(tsk, &cputime);
+                        thread_group_cputimer(tsk, &cputime);
                         utime = cputime.utime;
                         if (cputime_le(cval, utime)) { /* about to fire */
                                 cval = jiffies_to_cputime(1);
@@ -82,7 +82,7 @@ int do_getitimer(int which, struct itimerval *value)
                         struct task_cputime times;
                         cputime_t ptime;
 
-                        thread_group_cputime(tsk, &times);
+                        thread_group_cputimer(tsk, &times);
                         ptime = cputime_add(times.utime, times.stime);
                         if (cputime_le(cval, ptime)) { /* about to fire */
                                 cval = jiffies_to_cputime(1);
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index fa07da94d7be..2313a4cc14ea 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -230,6 +230,71 @@ static int cpu_clock_sample(const clockid_t which_clock, struct task_struct *p,
         return 0;
 }
 
+void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
+{
+        struct sighand_struct *sighand;
+        struct signal_struct *sig;
+        struct task_struct *t;
+
+        *times = INIT_CPUTIME;
+
+        rcu_read_lock();
+        sighand = rcu_dereference(tsk->sighand);
+        if (!sighand)
+                goto out;
+
+        sig = tsk->signal;
+
+        t = tsk;
+        do {
+                times->utime = cputime_add(times->utime, t->utime);
+                times->stime = cputime_add(times->stime, t->stime);
+                times->sum_exec_runtime += t->se.sum_exec_runtime;
+
+                t = next_thread(t);
+        } while (t != tsk);
+
+        times->utime = cputime_add(times->utime, sig->utime);
+        times->stime = cputime_add(times->stime, sig->stime);
+        times->sum_exec_runtime += sig->sum_sched_runtime;
+out:
+        rcu_read_unlock();
+}
+
+static void update_gt_cputime(struct task_cputime *a, struct task_cputime *b)
+{
+        if (cputime_gt(b->utime, a->utime))
+                a->utime = b->utime;
+
+        if (cputime_gt(b->stime, a->stime))
+                a->stime = b->stime;
+
+        if (b->sum_exec_runtime > a->sum_exec_runtime)
+                a->sum_exec_runtime = b->sum_exec_runtime;
+}
+
+void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times)
+{
+        struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
+        struct task_cputime sum;
+        unsigned long flags;
+
+        spin_lock_irqsave(&cputimer->lock, flags);
+        if (!cputimer->running) {
+                cputimer->running = 1;
+                /*
+                 * The POSIX timer interface allows for absolute time expiry
+                 * values through the TIMER_ABSTIME flag, therefore we have
+                 * to synchronize the timer to the clock every time we start
+                 * it.
+                 */
+                thread_group_cputime(tsk, &sum);
+                update_gt_cputime(&cputimer->cputime, &sum);
+        }
+        *times = cputimer->cputime;
+        spin_unlock_irqrestore(&cputimer->lock, flags);
+}
+
 /*
  * Sample a process (thread group) clock for the given group_leader task.
  * Must be called with tasklist_lock held for reading.
@@ -457,7 +522,7 @@ void posix_cpu_timers_exit_group(struct task_struct *tsk)
 {
         struct task_cputime cputime;
 
-        thread_group_cputime(tsk, &cputime);
+        thread_group_cputimer(tsk, &cputime);
         cleanup_timers(tsk->signal->cpu_timers,
                        cputime.utime, cputime.stime, cputime.sum_exec_runtime);
 }
@@ -964,6 +1029,19 @@ static void check_thread_timers(struct task_struct *tsk,
         }
 }
 
+static void stop_process_timers(struct task_struct *tsk)
+{
+        struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
+        unsigned long flags;
+
+        if (!cputimer->running)
+                return;
+
+        spin_lock_irqsave(&cputimer->lock, flags);
+        cputimer->running = 0;
+        spin_unlock_irqrestore(&cputimer->lock, flags);
+}
+
 /*
  * Check for any per-thread CPU timers that have fired and move them
  * off the tsk->*_timers list onto the firing list.  Per-thread timers
@@ -987,13 +1065,15 @@ static void check_process_timers(struct task_struct *tsk,
             sig->rlim[RLIMIT_CPU].rlim_cur == RLIM_INFINITY &&
             list_empty(&timers[CPUCLOCK_VIRT]) &&
             cputime_eq(sig->it_virt_expires, cputime_zero) &&
-            list_empty(&timers[CPUCLOCK_SCHED]))
+            list_empty(&timers[CPUCLOCK_SCHED])) {
+                stop_process_timers(tsk);
                 return;
+        }
 
         /*
          * Collect the current process totals.
          */
-        thread_group_cputime(tsk, &cputime);
+        thread_group_cputimer(tsk, &cputime);
         utime = cputime.utime;
         ptime = cputime_add(utime, cputime.stime);
         sum_sched_runtime = cputime.sum_exec_runtime;
@@ -1259,7 +1339,7 @@ static inline int fastpath_timer_check(struct task_struct *tsk)
         if (!task_cputime_zero(&sig->cputime_expires)) {
                 struct task_cputime group_sample;
 
-                thread_group_cputime(tsk, &group_sample);
+                thread_group_cputimer(tsk, &group_sample);
                 if (task_cputime_expired(&group_sample, &sig->cputime_expires))
                         return 1;
         }
@@ -1329,6 +1409,33 @@ void run_posix_cpu_timers(struct task_struct *tsk)
 }
 
 /*
+ * Sample a process (thread group) timer for the given group_leader task.
+ * Must be called with tasklist_lock held for reading.
+ */
+static int cpu_timer_sample_group(const clockid_t which_clock,
+                                  struct task_struct *p,
+                                  union cpu_time_count *cpu)
+{
+        struct task_cputime cputime;
+
+        thread_group_cputimer(p, &cputime);
+        switch (CPUCLOCK_WHICH(which_clock)) {
+        default:
+                return -EINVAL;
+        case CPUCLOCK_PROF:
+                cpu->cpu = cputime_add(cputime.utime, cputime.stime);
+                break;
+        case CPUCLOCK_VIRT:
+                cpu->cpu = cputime.utime;
+                break;
+        case CPUCLOCK_SCHED:
+                cpu->sched = cputime.sum_exec_runtime + task_delta_exec(p);
+                break;
+        }
+        return 0;
+}
+
+/*
  * Set one of the process-wide special case CPU timers.
  * The tsk->sighand->siglock must be held by the caller.
  * The *newval argument is relative and we update it to be absolute, *oldval
@@ -1341,7 +1448,7 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx,
         struct list_head *head;
 
         BUG_ON(clock_idx == CPUCLOCK_SCHED);
-        cpu_clock_sample_group(clock_idx, tsk, &now);
+        cpu_timer_sample_group(clock_idx, tsk, &now);
 
         if (oldval) {
                 if (!cputime_eq(*oldval, cputime_zero)) {
diff --git a/kernel/sched.c b/kernel/sched.c
index 1ffb89514871..5dc3b0a5d35a 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2266,16 +2266,6 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
         if (!sched_feat(SYNC_WAKEUPS))
                 sync = 0;
 
-        if (!sync) {
-                if (current->se.avg_overlap < sysctl_sched_migration_cost &&
-                          p->se.avg_overlap < sysctl_sched_migration_cost)
-                        sync = 1;
-        } else {
-                if (current->se.avg_overlap >= sysctl_sched_migration_cost ||
-                          p->se.avg_overlap >= sysctl_sched_migration_cost)
-                        sync = 0;
-        }
-
 #ifdef CONFIG_SMP
         if (sched_feat(LB_WAKEUP_UPDATE)) {
                 struct sched_domain *sd;
@@ -3890,19 +3880,24 @@ int select_nohz_load_balancer(int stop_tick)
         int cpu = smp_processor_id();
 
         if (stop_tick) {
-                cpumask_set_cpu(cpu, nohz.cpu_mask);
                 cpu_rq(cpu)->in_nohz_recently = 1;
 
-                /*
-                 * If we are going offline and still the leader, give up!
-                 */
-                if (!cpu_active(cpu) &&
-                    atomic_read(&nohz.load_balancer) == cpu) {
+                if (!cpu_active(cpu)) {
+                        if (atomic_read(&nohz.load_balancer) != cpu)
+                                return 0;
+
+                        /*
+                         * If we are going offline and still the leader,
+                         * give up!
+                         */
                         if (atomic_cmpxchg(&nohz.load_balancer, cpu, -1) != cpu)
                                 BUG();
+
                         return 0;
                 }
 
+                cpumask_set_cpu(cpu, nohz.cpu_mask);
+
                 /* time for ilb owner also to sleep */
                 if (cpumask_weight(nohz.cpu_mask) == num_online_cpus()) {
                         if (atomic_read(&nohz.load_balancer) == cpu)
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index a7e50ba185ac..0566f2a03c42 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -1191,15 +1191,20 @@ wake_affine(struct sched_domain *this_sd, struct rq *this_rq,
             int idx, unsigned long load, unsigned long this_load,
             unsigned int imbalance)
 {
+        struct task_struct *curr = this_rq->curr;
+        struct task_group *tg;
         unsigned long tl = this_load;
         unsigned long tl_per_task;
-        struct task_group *tg;
         unsigned long weight;
         int balanced;
 
         if (!(this_sd->flags & SD_WAKE_AFFINE) || !sched_feat(AFFINE_WAKEUPS))
                 return 0;
 
+        if (sync && (curr->se.avg_overlap > sysctl_sched_migration_cost ||
+                        p->se.avg_overlap > sysctl_sched_migration_cost))
+                sync = 0;
+
         /*
          * If sync wakeup then subtract the (maximum possible)
          * effect of the currently running task from the load
@@ -1426,7 +1431,9 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int sync)
         if (!sched_feat(WAKEUP_PREEMPT))
                 return;
 
-        if (sched_feat(WAKEUP_OVERLAP) && sync) {
+        if (sched_feat(WAKEUP_OVERLAP) && (sync ||
+                        (se->avg_overlap < sysctl_sched_migration_cost &&
+                         pse->avg_overlap < sysctl_sched_migration_cost))) {
                 resched_task(curr);
                 return;
         }
diff --git a/kernel/sched_stats.h b/kernel/sched_stats.h
index 8ab0cef8ecab..a8f93dd374e1 100644
--- a/kernel/sched_stats.h
+++ b/kernel/sched_stats.h
@@ -296,19 +296,21 @@ sched_info_switch(struct task_struct *prev, struct task_struct *next)
 static inline void account_group_user_time(struct task_struct *tsk,
                                            cputime_t cputime)
 {
-        struct task_cputime *times;
-        struct signal_struct *sig;
+        struct thread_group_cputimer *cputimer;
 
         /* tsk == current, ensure it is safe to use ->signal */
         if (unlikely(tsk->exit_state))
                 return;
 
-        sig = tsk->signal;
-        times = &sig->cputime.totals;
+        cputimer = &tsk->signal->cputimer;
 
-        spin_lock(&times->lock);
-        times->utime = cputime_add(times->utime, cputime);
-        spin_unlock(&times->lock);
+        if (!cputimer->running)
+                return;
+
+        spin_lock(&cputimer->lock);
+        cputimer->cputime.utime =
+                cputime_add(cputimer->cputime.utime, cputime);
+        spin_unlock(&cputimer->lock);
 }
 
 /**
@@ -324,19 +326,21 @@ static inline void account_group_user_time(struct task_struct *tsk,
 static inline void account_group_system_time(struct task_struct *tsk,
                                              cputime_t cputime)
 {
-        struct task_cputime *times;
-        struct signal_struct *sig;
+        struct thread_group_cputimer *cputimer;
 
         /* tsk == current, ensure it is safe to use ->signal */
         if (unlikely(tsk->exit_state))
                 return;
 
-        sig = tsk->signal;
-        times = &sig->cputime.totals;
+        cputimer = &tsk->signal->cputimer;
+
+        if (!cputimer->running)
+                return;
 
-        spin_lock(&times->lock);
-        times->stime = cputime_add(times->stime, cputime);
-        spin_unlock(&times->lock);
+        spin_lock(&cputimer->lock);
+        cputimer->cputime.stime =
+                cputime_add(cputimer->cputime.stime, cputime);
+        spin_unlock(&cputimer->lock);
 }
 
 /**
@@ -352,7 +356,7 @@ static inline void account_group_system_time(struct task_struct *tsk,
 static inline void account_group_exec_runtime(struct task_struct *tsk,
                                               unsigned long long ns)
 {
-        struct task_cputime *times;
+        struct thread_group_cputimer *cputimer;
         struct signal_struct *sig;
 
         sig = tsk->signal;
@@ -361,9 +365,12 @@ static inline void account_group_exec_runtime(struct task_struct *tsk,
         if (unlikely(!sig))
                 return;
 
-        times = &sig->cputime.totals;
+        cputimer = &sig->cputimer;
+
+        if (!cputimer->running)
+                return;
 
-        spin_lock(&times->lock);
-        times->sum_exec_runtime += ns;
-        spin_unlock(&times->lock);
+        spin_lock(&cputimer->lock);
+        cputimer->cputime.sum_exec_runtime += ns;
+        spin_unlock(&cputimer->lock);
 }
diff --git a/kernel/signal.c b/kernel/signal.c
index b6b36768b758..2a74fe87c0dd 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1367,7 +1367,6 @@ int do_notify_parent(struct task_struct *tsk, int sig)
         struct siginfo info;
         unsigned long flags;
         struct sighand_struct *psig;
-        struct task_cputime cputime;
         int ret = sig;
 
         BUG_ON(sig == -1);
@@ -1397,9 +1396,10 @@ int do_notify_parent(struct task_struct *tsk, int sig)
         info.si_uid = __task_cred(tsk)->uid;
         rcu_read_unlock();
 
-        thread_group_cputime(tsk, &cputime);
-        info.si_utime = cputime_to_jiffies(cputime.utime);
-        info.si_stime = cputime_to_jiffies(cputime.stime);
+        info.si_utime = cputime_to_clock_t(cputime_add(tsk->utime,
+                                tsk->signal->utime));
+        info.si_stime = cputime_to_clock_t(cputime_add(tsk->stime,
+                                tsk->signal->stime));
 
         info.si_status = tsk->exit_code & 0x7f;
         if (tsk->exit_code & 0x80)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 790f9d785663..c5ef44ff850f 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -101,6 +101,7 @@ static int two = 2;
 
 static int zero;
 static int one = 1;
+static unsigned long one_ul = 1;
 static int one_hundred = 100;
 
 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
@@ -974,7 +975,7 @@ static struct ctl_table vm_table[] = {
                 .mode           = 0644,
                 .proc_handler   = &dirty_background_bytes_handler,
                 .strategy       = &sysctl_intvec,
-                .extra1         = &one,
+                .extra1         = &one_ul,
         },
         {
                 .ctl_name       = VM_DIRTY_RATIO,
@@ -995,7 +996,7 @@ static struct ctl_table vm_table[] = {
                 .mode           = 0644,
                 .proc_handler   = &dirty_bytes_handler,
                 .strategy       = &sysctl_intvec,
-                .extra1         = &one,
+                .extra1         = &one_ul,
         },
         {
                 .procname       = "dirty_writeback_centisecs",
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 53ba3a6d16d0..a3901b550c93 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -59,7 +59,7 @@ enum {
         RB_BUFFERS_DISABLED     = 1 << RB_BUFFERS_DISABLED_BIT,
 };
 
-static long ring_buffer_flags __read_mostly = RB_BUFFERS_ON;
+static unsigned long ring_buffer_flags __read_mostly = RB_BUFFERS_ON;
 
 /**
  * tracing_on - enable all tracing buffers
@@ -91,7 +91,7 @@ EXPORT_SYMBOL_GPL(tracing_off);
  * tracing_off_permanent - permanently disable ring buffers
  *
  * This function, once called, will disable all ring buffers
- * permanenty.
+ * permanently.
  */
 void tracing_off_permanent(void)
 {
@@ -210,7 +210,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_event_data);
 
 struct buffer_data_page {
         u64              time_stamp;    /* page time stamp */
-        local_t          commit;        /* write commited index */
+        local_t          commit;        /* write committed index */
         unsigned char    data[];        /* data of buffer page */
 };
 
@@ -260,7 +260,7 @@ struct ring_buffer_per_cpu {
         struct list_head                pages;
         struct buffer_page              *head_page;     /* read from head */
         struct buffer_page              *tail_page;     /* write to tail */
-        struct buffer_page              *commit_page;   /* commited pages */
+        struct buffer_page              *commit_page;   /* committed pages */
         struct buffer_page              *reader_page;
         unsigned long                   overrun;
         unsigned long                   entries;
@@ -273,8 +273,8 @@ struct ring_buffer {
         unsigned                        pages;
         unsigned                        flags;
         int                             cpus;
-        cpumask_var_t                   cpumask;
         atomic_t                        record_disabled;
+        cpumask_var_t                   cpumask;
 
         struct mutex                    mutex;
 
@@ -303,7 +303,7 @@ struct ring_buffer_iter {
  * check_pages - integrity check of buffer pages
  * @cpu_buffer: CPU buffer with pages to test
  *
- * As a safty measure we check to make sure the data pages have not
+ * As a safety measure we check to make sure the data pages have not
  * been corrupted.
  */
 static int rb_check_pages(struct ring_buffer_per_cpu *cpu_buffer)
@@ -2332,13 +2332,14 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
 EXPORT_SYMBOL_GPL(ring_buffer_swap_cpu);
 
 static void rb_remove_entries(struct ring_buffer_per_cpu *cpu_buffer,
-                              struct buffer_data_page *bpage)
+                              struct buffer_data_page *bpage,
+                              unsigned int offset)
 {
         struct ring_buffer_event *event;
         unsigned long head;
 
         __raw_spin_lock(&cpu_buffer->lock);
-        for (head = 0; head < local_read(&bpage->commit);
+        for (head = offset; head < local_read(&bpage->commit);
              head += rb_event_length(event)) {
 
                 event = __rb_data_page_index(bpage, head);
@@ -2406,12 +2407,12 @@ void ring_buffer_free_read_page(struct ring_buffer *buffer, void *data)
  * to swap with a page in the ring buffer.
  *
  * for example:
- *      rpage = ring_buffer_alloc_page(buffer);
+ *      rpage = ring_buffer_alloc_read_page(buffer);
  *      if (!rpage)
  *              return error;
  *      ret = ring_buffer_read_page(buffer, &rpage, cpu, 0);
- *      if (ret)
- *              process_page(rpage);
+ *      if (ret >= 0)
+ *              process_page(rpage, ret);
  *
  * When @full is set, the function will not return true unless
  * the writer is off the reader page.
@@ -2422,8 +2423,8 @@ void ring_buffer_free_read_page(struct ring_buffer *buffer, void *data)
  *  responsible for that.
  *
  * Returns:
- *  1 if data has been transferred
- *  0 if no data has been transferred.
+ *  >=0 if data has been transferred, returns the offset of consumed data.
+ *  <0 if no data has been transferred.
  */
 int ring_buffer_read_page(struct ring_buffer *buffer,
                             void **data_page, int cpu, int full)
@@ -2432,7 +2433,8 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
         struct ring_buffer_event *event;
         struct buffer_data_page *bpage;
         unsigned long flags;
-        int ret = 0;
+        unsigned int read;
+        int ret = -1;
 
         if (!data_page)
                 return 0;
@@ -2454,25 +2456,29 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
         /* check for data */
         if (!local_read(&cpu_buffer->reader_page->page->commit))
                 goto out;
+
+        read = cpu_buffer->reader_page->read;
         /*
          * If the writer is already off of the read page, then simply
          * switch the read page with the given page. Otherwise
          * we need to copy the data from the reader to the writer.
          */
         if (cpu_buffer->reader_page == cpu_buffer->commit_page) {
-                unsigned int read = cpu_buffer->reader_page->read;
+                unsigned int commit = rb_page_commit(cpu_buffer->reader_page);
+                struct buffer_data_page *rpage = cpu_buffer->reader_page->page;
 
                 if (full)
                         goto out;
                 /* The writer is still on the reader page, we must copy */
-                bpage = cpu_buffer->reader_page->page;
-                memcpy(bpage->data,
-                       cpu_buffer->reader_page->page->data + read,
-                       local_read(&bpage->commit) - read);
+                memcpy(bpage->data + read, rpage->data + read, commit - read);
 
                 /* consume what was read */
-                cpu_buffer->reader_page += read;
+                cpu_buffer->reader_page->read = commit;
 
+                /* update bpage */
+                local_set(&bpage->commit, commit);
+                if (!read)
+                        bpage->time_stamp = rpage->time_stamp;
         } else {
                 /* swap the pages */
                 rb_init_page(bpage);
@@ -2481,10 +2487,10 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
                 cpu_buffer->reader_page->read = 0;
                 *data_page = bpage;
         }
-        ret = 1;
+        ret = read;
 
         /* update the entry counter */
-        rb_remove_entries(cpu_buffer, bpage);
+        rb_remove_entries(cpu_buffer, bpage, read);
  out:
         spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
 
@@ -2495,7 +2501,7 @@ static ssize_t
 rb_simple_read(struct file *filp, char __user *ubuf,
                size_t cnt, loff_t *ppos)
 {
-        long *p = filp->private_data;
+        unsigned long *p = filp->private_data;
         char buf[64];
         int r;
 
@@ -2511,9 +2517,9 @@ static ssize_t
 rb_simple_write(struct file *filp, const char __user *ubuf,
                 size_t cnt, loff_t *ppos)
 {
-        long *p = filp->private_data;
+        unsigned long *p = filp->private_data;
         char buf[64];
-        long val;
+        unsigned long val;
         int ret;
 
         if (cnt >= sizeof(buf))
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index d89821283b47..95f99a7abf2f 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -80,7 +80,7 @@ static int dummy_set_flag(u32 old_flags, u32 bit, int set)
  * of the tracer is successful. But that is the only place that sets
  * this back to zero.
  */
-int tracing_disabled = 1;
+static int tracing_disabled = 1;
 
 static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled);
 
@@ -459,6 +459,8 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
  * Register a new plugin tracer.
  */
 int register_tracer(struct tracer *type)
+__releases(kernel_lock)
+__acquires(kernel_lock)
 {
         struct tracer *t;
         int len;
@@ -626,7 +628,7 @@ static int cmdline_idx;
 static DEFINE_SPINLOCK(trace_cmdline_lock);
 
 /* temporary disable recording */
-atomic_t trace_record_cmdline_disabled __read_mostly;
+static atomic_t trace_record_cmdline_disabled __read_mostly;
 
 static void trace_init_cmdlines(void)
 {
@@ -983,10 +985,12 @@ static void ftrace_trace_userstack(struct trace_array *tr,
 #endif
 }
 
-void __trace_userstack(struct trace_array *tr, unsigned long flags)
+#ifdef UNUSED
+static void __trace_userstack(struct trace_array *tr, unsigned long flags)
 {
         ftrace_trace_userstack(tr, flags, preempt_count());
 }
+#endif /* UNUSED */
 
 static void
 ftrace_trace_special(void *__tr,
@@ -1720,7 +1724,7 @@ int tracing_open_generic(struct inode *inode, struct file *filp)
         return 0;
 }
 
-int tracing_release(struct inode *inode, struct file *file)
+static int tracing_release(struct inode *inode, struct file *file)
 {
         struct seq_file *m = (struct seq_file *)file->private_data;
         struct trace_iterator *iter = m->private;
@@ -1963,7 +1967,7 @@ tracing_trace_options_read(struct file *filp, char __user *ubuf,
         struct tracer_opt *trace_opts = current_trace->flags->opts;
 
 
-        /* calulate max size */
+        /* calculate max size */
         for (i = 0; trace_options[i]; i++) {
                 len += strlen(trace_options[i]);
                 len += 3; /* "no" and space */
@@ -2145,7 +2149,7 @@ tracing_ctrl_write(struct file *filp, const char __user *ubuf,
 {
         struct trace_array *tr = filp->private_data;
         char buf[64];
-        long val;
+        unsigned long val;
         int ret;
 
         if (cnt >= sizeof(buf))
@@ -2293,9 +2297,9 @@ static ssize_t
 tracing_max_lat_write(struct file *filp, const char __user *ubuf,
                       size_t cnt, loff_t *ppos)
 {
-        long *ptr = filp->private_data;
+        unsigned long *ptr = filp->private_data;
         char buf[64];
-        long val;
+        unsigned long val;
         int ret;
 
         if (cnt >= sizeof(buf))
diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c
index f8ae2c50e01d..c2e68d440c4d 100644
--- a/kernel/trace/trace_branch.c
+++ b/kernel/trace/trace_branch.c
@@ -91,8 +91,6 @@ void trace_likely_condition(struct ftrace_branch_data *f, int val, int expect)
 
 int enable_branch_tracing(struct trace_array *tr)
 {
-        int ret = 0;
-
         mutex_lock(&branch_tracing_mutex);
         branch_tracer = tr;
         /*
@@ -103,7 +101,7 @@ int enable_branch_tracing(struct trace_array *tr)
         branch_tracing_enabled++;
         mutex_unlock(&branch_tracing_mutex);
 
-        return ret;
+        return 0;
 }
 
 void disable_branch_tracing(void)
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 782ec0fdf453..519a0cab1530 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -186,30 +186,30 @@ verif_pid(struct trace_seq *s, pid_t pid, int cpu, pid_t *last_pids_cpu)
         ret = trace_seq_printf(s,
                 " ------------------------------------------\n");
         if (!ret)
-                TRACE_TYPE_PARTIAL_LINE;
+                return TRACE_TYPE_PARTIAL_LINE;
 
         ret = print_graph_cpu(s, cpu);
         if (ret == TRACE_TYPE_PARTIAL_LINE)
-                TRACE_TYPE_PARTIAL_LINE;
+                return TRACE_TYPE_PARTIAL_LINE;
 
         ret = print_graph_proc(s, prev_pid);
         if (ret == TRACE_TYPE_PARTIAL_LINE)
-                TRACE_TYPE_PARTIAL_LINE;
+                return TRACE_TYPE_PARTIAL_LINE;
 
         ret = trace_seq_printf(s, " => ");
         if (!ret)
-                TRACE_TYPE_PARTIAL_LINE;
+                return TRACE_TYPE_PARTIAL_LINE;
 
         ret = print_graph_proc(s, pid);
         if (ret == TRACE_TYPE_PARTIAL_LINE)
-                TRACE_TYPE_PARTIAL_LINE;
+                return TRACE_TYPE_PARTIAL_LINE;
 
         ret = trace_seq_printf(s,
                 "\n ------------------------------------------\n\n");
         if (!ret)
-                TRACE_TYPE_PARTIAL_LINE;
+                return TRACE_TYPE_PARTIAL_LINE;
 
-        return ret;
+        return TRACE_TYPE_HANDLED;
 }
 
 static struct ftrace_graph_ret_entry *
diff --git a/kernel/trace/trace_hw_branches.c b/kernel/trace/trace_hw_branches.c
index e3e7db61c067..0794dd33f27b 100644
--- a/kernel/trace/trace_hw_branches.c
+++ b/kernel/trace/trace_hw_branches.c
@@ -75,7 +75,7 @@ static void bts_trace_start(struct trace_array *tr)
 }
 
 /*
- * Start tracing on the current cpu.
+ * Stop tracing on the current cpu.
  * The argument is ignored.
  *
  * pre: bts_tracer_mutex must be locked.
diff --git a/kernel/trace/trace_sysprof.c b/kernel/trace/trace_sysprof.c
index 9902c15997ad..7c9a2d82a7d8 100644
--- a/kernel/trace/trace_sysprof.c
+++ b/kernel/trace/trace_sysprof.c
@@ -88,7 +88,7 @@ static void backtrace_address(void *data, unsigned long addr, int reliable)
         }
 }
 
-const static struct stacktrace_ops backtrace_ops = {
+static const struct stacktrace_ops backtrace_ops = {
         .warning                = backtrace_warning,
         .warning_symbol         = backtrace_warning_symbol,
         .stack                  = backtrace_stack,