Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

Conflicts:
	net/sched/sch_hfsc.c
	net/sched/sch_htb.c
	net/sched/sch_tbf.c

14 files changed, 325 insertions, 232 deletions

diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index 31d766bf5d2e..8e42fec7686d 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -9,9 +9,6 @@ menu "IRQ subsystem"
 config GENERIC_HARDIRQS
        def_bool y
 
-config GENERIC_HARDIRQS_NO__DO_IRQ
-       def_bool y
-
 # Select this to disable the deprecated stuff
 config GENERIC_HARDIRQS_NO_DEPRECATED
        def_bool n
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index e2347eb63306..3540a7190122 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -118,114 +118,3 @@ irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action)
 
         return retval;
 }
-
-#ifndef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
-
-#ifdef CONFIG_ENABLE_WARN_DEPRECATED
-# warning __do_IRQ is deprecated. Please convert to proper flow handlers
-#endif
-
-/**
- * __do_IRQ - original all in one highlevel IRQ handler
- * @irq:        the interrupt number
- *
- * __do_IRQ handles all normal device IRQ's (the special
- * SMP cross-CPU interrupts have their own specific
- * handlers).
- *
- * This is the original x86 implementation which is used for every
- * interrupt type.
- */
-unsigned int __do_IRQ(unsigned int irq)
-{
-        struct irq_desc *desc = irq_to_desc(irq);
-        struct irqaction *action;
-        unsigned int status;
-
-        kstat_incr_irqs_this_cpu(irq, desc);
-
-        if (CHECK_IRQ_PER_CPU(desc->status)) {
-                irqreturn_t action_ret;
-
-                /*
-                 * No locking required for CPU-local interrupts:
-                 */
-                if (desc->irq_data.chip->ack)
-                        desc->irq_data.chip->ack(irq);
-                if (likely(!(desc->status & IRQ_DISABLED))) {
-                        action_ret = handle_IRQ_event(irq, desc->action);
-                        if (!noirqdebug)
-                                note_interrupt(irq, desc, action_ret);
-                }
-                desc->irq_data.chip->end(irq);
-                return 1;
-        }
-
-        raw_spin_lock(&desc->lock);
-        if (desc->irq_data.chip->ack)
-                desc->irq_data.chip->ack(irq);
-        /*
-         * REPLAY is when Linux resends an IRQ that was dropped earlier
-         * WAITING is used by probe to mark irqs that are being tested
-         */
-        status = desc->status & ~(IRQ_REPLAY | IRQ_WAITING);
-        status |= IRQ_PENDING; /* we _want_ to handle it */
-
-        /*
-         * If the IRQ is disabled for whatever reason, we cannot
-         * use the action we have.
-         */
-        action = NULL;
-        if (likely(!(status & (IRQ_DISABLED | IRQ_INPROGRESS)))) {
-                action = desc->action;
-                status &= ~IRQ_PENDING; /* we commit to handling */
-                status |= IRQ_INPROGRESS; /* we are handling it */
-        }
-        desc->status = status;
-
-        /*
-         * If there is no IRQ handler or it was disabled, exit early.
-         * Since we set PENDING, if another processor is handling
-         * a different instance of this same irq, the other processor
-         * will take care of it.
-         */
-        if (unlikely(!action))
-                goto out;
-
-        /*
-         * Edge triggered interrupts need to remember
-         * pending events.
-         * This applies to any hw interrupts that allow a second
-         * instance of the same irq to arrive while we are in do_IRQ
-         * or in the handler. But the code here only handles the _second_
-         * instance of the irq, not the third or fourth. So it is mostly
-         * useful for irq hardware that does not mask cleanly in an
-         * SMP environment.
-         */
-        for (;;) {
-                irqreturn_t action_ret;
-
-                raw_spin_unlock(&desc->lock);
-
-                action_ret = handle_IRQ_event(irq, action);
-                if (!noirqdebug)
-                        note_interrupt(irq, desc, action_ret);
-
-                raw_spin_lock(&desc->lock);
-                if (likely(!(desc->status & IRQ_PENDING)))
-                        break;
-                desc->status &= ~IRQ_PENDING;
-        }
-        desc->status &= ~IRQ_INPROGRESS;
-
-out:
-        /*
-         * The ->end() handler has to deal with interrupts which got
-         * disabled while the handler was running.
-         */
-        desc->irq_data.chip->end(irq);
-        raw_spin_unlock(&desc->lock);
-
-        return 1;
-}
-#endif
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 42ba65dff7d9..0d2058da80f5 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -2292,22 +2292,6 @@ mark_held_locks(struct task_struct *curr, enum mark_type mark)
 }
 
 /*
- * Debugging helper: via this flag we know that we are in
- * 'early bootup code', and will warn about any invalid irqs-on event:
- */
-static int early_boot_irqs_enabled;
-
-void early_boot_irqs_off(void)
-{
-        early_boot_irqs_enabled = 0;
-}
-
-void early_boot_irqs_on(void)
-{
-        early_boot_irqs_enabled = 1;
-}
-
-/*
  * Hardirqs will be enabled:
  */
 void trace_hardirqs_on_caller(unsigned long ip)
@@ -2319,7 +2303,7 @@ void trace_hardirqs_on_caller(unsigned long ip)
         if (unlikely(!debug_locks || current->lockdep_recursion))
                 return;
 
-        if (DEBUG_LOCKS_WARN_ON(unlikely(!early_boot_irqs_enabled)))
+        if (DEBUG_LOCKS_WARN_ON(unlikely(early_boot_irqs_disabled)))
                 return;
 
         if (unlikely(curr->hardirqs_enabled)) {
diff --git a/kernel/params.c b/kernel/params.c
index 08107d181758..0da1411222b9 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -719,9 +719,7 @@ void destroy_params(const struct kernel_param *params, unsigned num)
                         params[i].ops->free(params[i].arg);
 }
 
-static void __init kernel_add_sysfs_param(const char *name,
-                                          struct kernel_param *kparam,
-                                          unsigned int name_skip)
+static struct module_kobject * __init locate_module_kobject(const char *name)
 {
         struct module_kobject *mk;
         struct kobject *kobj;
@@ -729,10 +727,7 @@ static void __init kernel_add_sysfs_param(const char *name,
 
         kobj = kset_find_obj(module_kset, name);
         if (kobj) {
-                /* We already have one.  Remove params so we can add more. */
                 mk = to_module_kobject(kobj);
-                /* We need to remove it before adding parameters. */
-                sysfs_remove_group(&mk->kobj, &mk->mp->grp);
         } else {
                 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
                 BUG_ON(!mk);
@@ -743,15 +738,36 @@ static void __init kernel_add_sysfs_param(const char *name,
                                            "%s", name);
                 if (err) {
                         kobject_put(&mk->kobj);
-                        printk(KERN_ERR "Module '%s' failed add to sysfs, "
-                               "error number %d\n", name, err);
-                        printk(KERN_ERR "The system will be unstable now.\n");
-                        return;
+                        printk(KERN_ERR
+                                "Module '%s' failed add to sysfs, error number %d\n",
+                                name, err);
+                        printk(KERN_ERR
+                                "The system will be unstable now.\n");
+                        return NULL;
                 }
-                /* So that exit path is even. */
+
+                /* So that we hold reference in both cases. */
                 kobject_get(&mk->kobj);
         }
 
+        return mk;
+}
+
+static void __init kernel_add_sysfs_param(const char *name,
+                                          struct kernel_param *kparam,
+                                          unsigned int name_skip)
+{
+        struct module_kobject *mk;
+        int err;
+
+        mk = locate_module_kobject(name);
+        if (!mk)
+                return;
+
+        /* We need to remove old parameters before adding more. */
+        if (mk->mp)
+                sysfs_remove_group(&mk->kobj, &mk->mp->grp);
+
         /* These should not fail at boot. */
         err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
         BUG_ON(err);
@@ -796,6 +812,32 @@ static void __init param_sysfs_builtin(void)
         }
 }
 
+ssize_t __modver_version_show(struct module_attribute *mattr,
+                              struct module *mod, char *buf)
+{
+        struct module_version_attribute *vattr =
+                container_of(mattr, struct module_version_attribute, mattr);
+
+        return sprintf(buf, "%s\n", vattr->version);
+}
+
+extern struct module_version_attribute __start___modver[], __stop___modver[];
+
+static void __init version_sysfs_builtin(void)
+{
+        const struct module_version_attribute *vattr;
+        struct module_kobject *mk;
+        int err;
+
+        for (vattr = __start___modver; vattr < __stop___modver; vattr++) {
+                mk = locate_module_kobject(vattr->module_name);
+                if (mk) {
+                        err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
+                        kobject_uevent(&mk->kobj, KOBJ_ADD);
+                        kobject_put(&mk->kobj);
+                }
+        }
+}
 
 /* module-related sysfs stuff */
 
@@ -875,6 +917,7 @@ static int __init param_sysfs_init(void)
         }
         module_sysfs_initialized = 1;
 
+        version_sysfs_builtin();
         param_sysfs_builtin();
 
         return 0;
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 84522c796987..126a302c481c 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -2201,13 +2201,6 @@ find_lively_task_by_vpid(pid_t vpid)
         if (!task)
                 return ERR_PTR(-ESRCH);
 
-        /*
-         * Can't attach events to a dying task.
-         */
-        err = -ESRCH;
-        if (task->flags & PF_EXITING)
-                goto errout;
-
         /* Reuse ptrace permission checks for now. */
         err = -EACCES;
         if (!ptrace_may_access(task, PTRACE_MODE_READ))
@@ -2268,14 +2261,27 @@ retry:
 
                 get_ctx(ctx);
 
-                if (cmpxchg(&task->perf_event_ctxp[ctxn], NULL, ctx)) {
-                        /*
-                         * We raced with some other task; use
-                         * the context they set.
-                         */
+                err = 0;
+                mutex_lock(&task->perf_event_mutex);
+                /*
+                 * If it has already passed perf_event_exit_task().
+                 * we must see PF_EXITING, it takes this mutex too.
+                 */
+                if (task->flags & PF_EXITING)
+                        err = -ESRCH;
+                else if (task->perf_event_ctxp[ctxn])
+                        err = -EAGAIN;
+                else
+                        rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx);
+                mutex_unlock(&task->perf_event_mutex);
+
+                if (unlikely(err)) {
                         put_task_struct(task);
                         kfree(ctx);
-                        goto retry;
+
+                        if (err == -EAGAIN)
+                                goto retry;
+                        goto errout;
                 }
         }
 
@@ -5374,6 +5380,8 @@ free_dev:
         goto out;
 }
 
+static struct lock_class_key cpuctx_mutex;
+
 int perf_pmu_register(struct pmu *pmu, char *name, int type)
 {
         int cpu, ret;
@@ -5422,6 +5430,7 @@ skip_type:
 
                 cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu);
                 __perf_event_init_context(&cpuctx->ctx);
+                lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex);
                 cpuctx->ctx.type = cpu_context;
                 cpuctx->ctx.pmu = pmu;
                 cpuctx->jiffies_interval = 1;
@@ -6127,7 +6136,7 @@ static void perf_event_exit_task_context(struct task_struct *child, int ctxn)
          * scheduled, so we are now safe from rescheduling changing
          * our context.
          */
-        child_ctx = child->perf_event_ctxp[ctxn];
+        child_ctx = rcu_dereference_raw(child->perf_event_ctxp[ctxn]);
         task_ctx_sched_out(child_ctx, EVENT_ALL);
 
         /*
@@ -6440,11 +6449,6 @@ int perf_event_init_context(struct task_struct *child, int ctxn)
         unsigned long flags;
         int ret = 0;
 
-        child->perf_event_ctxp[ctxn] = NULL;
-
-        mutex_init(&child->perf_event_mutex);
-        INIT_LIST_HEAD(&child->perf_event_list);
-
         if (likely(!parent->perf_event_ctxp[ctxn]))
                 return 0;
 
@@ -6533,6 +6537,10 @@ int perf_event_init_task(struct task_struct *child)
 {
         int ctxn, ret;
 
+        memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp));
+        mutex_init(&child->perf_event_mutex);
+        INIT_LIST_HEAD(&child->perf_event_list);
+
         for_each_task_context_nr(ctxn) {
                 ret = perf_event_init_context(child, ctxn);
                 if (ret)
diff --git a/kernel/sched.c b/kernel/sched.c
index ea3e5eff3878..18d38e4ec7ba 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -553,9 +553,6 @@ struct rq {
         /* try_to_wake_up() stats */
         unsigned int ttwu_count;
         unsigned int ttwu_local;
-
-        /* BKL stats */
-        unsigned int bkl_count;
 #endif
 };
 
@@ -609,6 +606,9 @@ static inline struct task_group *task_group(struct task_struct *p)
         struct task_group *tg;
         struct cgroup_subsys_state *css;
 
+        if (p->flags & PF_EXITING)
+                return &root_task_group;
+
         css = task_subsys_state_check(p, cpu_cgroup_subsys_id,
                         lockdep_is_held(&task_rq(p)->lock));
         tg = container_of(css, struct task_group, css);
@@ -3887,7 +3887,7 @@ static inline void schedule_debug(struct task_struct *prev)
         schedstat_inc(this_rq(), sched_count);
 #ifdef CONFIG_SCHEDSTATS
         if (unlikely(prev->lock_depth >= 0)) {
-                schedstat_inc(this_rq(), bkl_count);
+                schedstat_inc(this_rq(), rq_sched_info.bkl_count);
                 schedstat_inc(prev, sched_info.bkl_count);
         }
 #endif
@@ -4871,7 +4871,8 @@ recheck:
                  * assigned.
                  */
                 if (rt_bandwidth_enabled() && rt_policy(policy) &&
-                                task_group(p)->rt_bandwidth.rt_runtime == 0) {
+                                task_group(p)->rt_bandwidth.rt_runtime == 0 &&
+                                !task_group_is_autogroup(task_group(p))) {
                         __task_rq_unlock(rq);
                         raw_spin_unlock_irqrestore(&p->pi_lock, flags);
                         return -EPERM;
@@ -8882,6 +8883,20 @@ cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
         }
 }
 
+static void
+cpu_cgroup_exit(struct cgroup_subsys *ss, struct task_struct *task)
+{
+        /*
+         * cgroup_exit() is called in the copy_process() failure path.
+         * Ignore this case since the task hasn't ran yet, this avoids
+         * trying to poke a half freed task state from generic code.
+         */
+        if (!(task->flags & PF_EXITING))
+                return;
+
+        sched_move_task(task);
+}
+
 #ifdef CONFIG_FAIR_GROUP_SCHED
 static int cpu_shares_write_u64(struct cgroup *cgrp, struct cftype *cftype,
                                 u64 shareval)
@@ -8954,6 +8969,7 @@ struct cgroup_subsys cpu_cgroup_subsys = {
         .destroy        = cpu_cgroup_destroy,
         .can_attach     = cpu_cgroup_can_attach,
         .attach         = cpu_cgroup_attach,
+        .exit           = cpu_cgroup_exit,
         .populate       = cpu_cgroup_populate,
         .subsys_id      = cpu_cgroup_subsys_id,
         .early_init     = 1,
diff --git a/kernel/sched_autogroup.c b/kernel/sched_autogroup.c
index 32a723b8f84c..9fb656283157 100644
--- a/kernel/sched_autogroup.c
+++ b/kernel/sched_autogroup.c
@@ -27,6 +27,11 @@ static inline void autogroup_destroy(struct kref *kref)
 {
         struct autogroup *ag = container_of(kref, struct autogroup, kref);
 
+#ifdef CONFIG_RT_GROUP_SCHED
+        /* We've redirected RT tasks to the root task group... */
+        ag->tg->rt_se = NULL;
+        ag->tg->rt_rq = NULL;
+#endif
         sched_destroy_group(ag->tg);
 }
 
@@ -55,6 +60,10 @@ static inline struct autogroup *autogroup_task_get(struct task_struct *p)
         return ag;
 }
 
+#ifdef CONFIG_RT_GROUP_SCHED
+static void free_rt_sched_group(struct task_group *tg);
+#endif
+
 static inline struct autogroup *autogroup_create(void)
 {
         struct autogroup *ag = kzalloc(sizeof(*ag), GFP_KERNEL);
@@ -72,6 +81,19 @@ static inline struct autogroup *autogroup_create(void)
         init_rwsem(&ag->lock);
         ag->id = atomic_inc_return(&autogroup_seq_nr);
         ag->tg = tg;
+#ifdef CONFIG_RT_GROUP_SCHED
+        /*
+         * Autogroup RT tasks are redirected to the root task group
+         * so we don't have to move tasks around upon policy change,
+         * or flail around trying to allocate bandwidth on the fly.
+         * A bandwidth exception in __sched_setscheduler() allows
+         * the policy change to proceed.  Thereafter, task_group()
+         * returns &root_task_group, so zero bandwidth is required.
+         */
+        free_rt_sched_group(tg);
+        tg->rt_se = root_task_group.rt_se;
+        tg->rt_rq = root_task_group.rt_rq;
+#endif
         tg->autogroup = ag;
 
         return ag;
@@ -106,6 +128,11 @@ task_wants_autogroup(struct task_struct *p, struct task_group *tg)
         return true;
 }
 
+static inline bool task_group_is_autogroup(struct task_group *tg)
+{
+        return tg != &root_task_group && tg->autogroup;
+}
+
 static inline struct task_group *
 autogroup_task_group(struct task_struct *p, struct task_group *tg)
 {
@@ -231,6 +258,11 @@ void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m)
 #ifdef CONFIG_SCHED_DEBUG
 static inline int autogroup_path(struct task_group *tg, char *buf, int buflen)
 {
+        int enabled = ACCESS_ONCE(sysctl_sched_autogroup_enabled);
+
+        if (!enabled || !tg->autogroup)
+                return 0;
+
         return snprintf(buf, buflen, "%s-%ld", "/autogroup", tg->autogroup->id);
 }
 #endif /* CONFIG_SCHED_DEBUG */
diff --git a/kernel/sched_autogroup.h b/kernel/sched_autogroup.h
index 5358e241cb20..7b859ffe5dad 100644
--- a/kernel/sched_autogroup.h
+++ b/kernel/sched_autogroup.h
@@ -15,6 +15,10 @@ autogroup_task_group(struct task_struct *p, struct task_group *tg);
 
 static inline void autogroup_init(struct task_struct *init_task) {  }
 static inline void autogroup_free(struct task_group *tg) { }
+static inline bool task_group_is_autogroup(struct task_group *tg)
+{
+        return 0;
+}
 
 static inline struct task_group *
 autogroup_task_group(struct task_struct *p, struct task_group *tg)
diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c
index 1dfae3d014b5..eb6cb8edd075 100644
--- a/kernel/sched_debug.c
+++ b/kernel/sched_debug.c
@@ -16,6 +16,8 @@
 #include <linux/kallsyms.h>
 #include <linux/utsname.h>
 
+static DEFINE_SPINLOCK(sched_debug_lock);
+
 /*
  * This allows printing both to /proc/sched_debug and
  * to the console
@@ -86,6 +88,26 @@ static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group
 }
 #endif
 
+#ifdef CONFIG_CGROUP_SCHED
+static char group_path[PATH_MAX];
+
+static char *task_group_path(struct task_group *tg)
+{
+        if (autogroup_path(tg, group_path, PATH_MAX))
+                return group_path;
+
+        /*
+         * May be NULL if the underlying cgroup isn't fully-created yet
+         */
+        if (!tg->css.cgroup) {
+                group_path[0] = '\0';
+                return group_path;
+        }
+        cgroup_path(tg->css.cgroup, group_path, PATH_MAX);
+        return group_path;
+}
+#endif
+
 static void
 print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
 {
@@ -108,6 +130,9 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
         SEQ_printf(m, "%15Ld %15Ld %15Ld.%06ld %15Ld.%06ld %15Ld.%06ld",
                 0LL, 0LL, 0LL, 0L, 0LL, 0L, 0LL, 0L);
 #endif
+#ifdef CONFIG_CGROUP_SCHED
+        SEQ_printf(m, " %s", task_group_path(task_group(p)));
+#endif
 
         SEQ_printf(m, "\n");
 }
@@ -144,7 +169,11 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
         struct sched_entity *last;
         unsigned long flags;
 
+#ifdef CONFIG_FAIR_GROUP_SCHED
+        SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, task_group_path(cfs_rq->tg));
+#else
         SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
+#endif
         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "exec_clock",
                         SPLIT_NS(cfs_rq->exec_clock));
 
@@ -191,7 +220,11 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 
 void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
 {
+#ifdef CONFIG_RT_GROUP_SCHED
+        SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, task_group_path(rt_rq->tg));
+#else
         SEQ_printf(m, "\nrt_rq[%d]:\n", cpu);
+#endif
 
 #define P(x) \
         SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
@@ -212,6 +245,7 @@ extern __read_mostly int sched_clock_running;
 static void print_cpu(struct seq_file *m, int cpu)
 {
         struct rq *rq = cpu_rq(cpu);
+        unsigned long flags;
 
 #ifdef CONFIG_X86
         {
@@ -262,14 +296,20 @@ static void print_cpu(struct seq_file *m, int cpu)
         P(ttwu_count);
         P(ttwu_local);
 
-        P(bkl_count);
+        SEQ_printf(m, "  .%-30s: %d\n", "bkl_count",
+                                rq->rq_sched_info.bkl_count);
 
 #undef P
+#undef P64
 #endif
+        spin_lock_irqsave(&sched_debug_lock, flags);
         print_cfs_stats(m, cpu);
         print_rt_stats(m, cpu);
 
+        rcu_read_lock();
         print_rq(m, rq, cpu);
+        rcu_read_unlock();
+        spin_unlock_irqrestore(&sched_debug_lock, flags);
 }
 
 static const char *sched_tunable_scaling_names[] = {
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index c62ebae65cf0..354769979c02 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -699,7 +699,8 @@ account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
         cfs_rq->nr_running--;
 }
 
-#if defined CONFIG_SMP && defined CONFIG_FAIR_GROUP_SCHED
+#ifdef CONFIG_FAIR_GROUP_SCHED
+# ifdef CONFIG_SMP
 static void update_cfs_rq_load_contribution(struct cfs_rq *cfs_rq,
                                             int global_update)
 {
@@ -762,6 +763,51 @@ static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update)
                 list_del_leaf_cfs_rq(cfs_rq);
 }
 
+static long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg,
+                                long weight_delta)
+{
+        long load_weight, load, shares;
+
+        load = cfs_rq->load.weight + weight_delta;
+
+        load_weight = atomic_read(&tg->load_weight);
+        load_weight -= cfs_rq->load_contribution;
+        load_weight += load;
+
+        shares = (tg->shares * load);
+        if (load_weight)
+                shares /= load_weight;
+
+        if (shares < MIN_SHARES)
+                shares = MIN_SHARES;
+        if (shares > tg->shares)
+                shares = tg->shares;
+
+        return shares;
+}
+
+static void update_entity_shares_tick(struct cfs_rq *cfs_rq)
+{
+        if (cfs_rq->load_unacc_exec_time > sysctl_sched_shares_window) {
+                update_cfs_load(cfs_rq, 0);
+                update_cfs_shares(cfs_rq, 0);
+        }
+}
+# else /* CONFIG_SMP */
+static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update)
+{
+}
+
+static inline long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg,
+                                long weight_delta)
+{
+        return tg->shares;
+}
+
+static inline void update_entity_shares_tick(struct cfs_rq *cfs_rq)
+{
+}
+# endif /* CONFIG_SMP */
 static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se,
                             unsigned long weight)
 {
@@ -782,7 +828,7 @@ static void update_cfs_shares(struct cfs_rq *cfs_rq, long weight_delta)
 {
         struct task_group *tg;
         struct sched_entity *se;
-        long load_weight, load, shares;
+        long shares;
 
         if (!cfs_rq)
                 return;
@@ -791,32 +837,14 @@ static void update_cfs_shares(struct cfs_rq *cfs_rq, long weight_delta)
         se = tg->se[cpu_of(rq_of(cfs_rq))];
         if (!se)
                 return;
-
-        load = cfs_rq->load.weight + weight_delta;
-
-        load_weight = atomic_read(&tg->load_weight);
-        load_weight -= cfs_rq->load_contribution;
-        load_weight += load;
-
-        shares = (tg->shares * load);
-        if (load_weight)
-                shares /= load_weight;
-
-        if (shares < MIN_SHARES)
-                shares = MIN_SHARES;
-        if (shares > tg->shares)
-                shares = tg->shares;
+#ifndef CONFIG_SMP
+        if (likely(se->load.weight == tg->shares))
+                return;
+#endif
+        shares = calc_cfs_shares(cfs_rq, tg, weight_delta);
 
         reweight_entity(cfs_rq_of(se), se, shares);
 }
-
-static void update_entity_shares_tick(struct cfs_rq *cfs_rq)
-{
-        if (cfs_rq->load_unacc_exec_time > sysctl_sched_shares_window) {
-                update_cfs_load(cfs_rq, 0);
-                update_cfs_shares(cfs_rq, 0);
-        }
-}
 #else /* CONFIG_FAIR_GROUP_SCHED */
 static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update)
 {
@@ -1062,6 +1090,9 @@ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
                 struct sched_entity *se = __pick_next_entity(cfs_rq);
                 s64 delta = curr->vruntime - se->vruntime;
 
+                if (delta < 0)
+                        return;
+
                 if (delta > ideal_runtime)
                         resched_task(rq_of(cfs_rq)->curr);
         }
@@ -1362,27 +1393,27 @@ static long effective_load(struct task_group *tg, int cpu, long wl, long wg)
                 return wl;
 
         for_each_sched_entity(se) {
-                long S, rw, s, a, b;
+                long lw, w;
 
-                S = se->my_q->tg->shares;
-                s = se->load.weight;
-                rw = se->my_q->load.weight;
+                tg = se->my_q->tg;
+                w = se->my_q->load.weight;
 
-                a = S*(rw + wl);
-                b = S*rw + s*wg;
+                /* use this cpu's instantaneous contribution */
+                lw = atomic_read(&tg->load_weight);
+                lw -= se->my_q->load_contribution;
+                lw += w + wg;
 
-                wl = s*(a-b);
+                wl += w;
 
-                if (likely(b))
-                        wl /= b;
+                if (lw > 0 && wl < lw)
+                        wl = (wl * tg->shares) / lw;
+                else
+                        wl = tg->shares;
 
-                /*
-                 * Assume the group is already running and will
-                 * thus already be accounted for in the weight.
-                 *
-                 * That is, moving shares between CPUs, does not
-                 * alter the group weight.
-                 */
+                /* zero point is MIN_SHARES */
+                if (wl < MIN_SHARES)
+                        wl = MIN_SHARES;
+                wl -= se->load.weight;
                 wg = 0;
         }
 
diff --git a/kernel/smp.c b/kernel/smp.c
index 4ec30e069987..9910744f0856 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -194,23 +194,52 @@ void generic_smp_call_function_interrupt(void)
          */
         list_for_each_entry_rcu(data, &call_function.queue, csd.list) {
                 int refs;
+                void (*func) (void *info);
 
-                if (!cpumask_test_and_clear_cpu(cpu, data->cpumask))
+                /*
+                 * Since we walk the list without any locks, we might
+                 * see an entry that was completed, removed from the
+                 * list and is in the process of being reused.
+                 *
+                 * We must check that the cpu is in the cpumask before
+                 * checking the refs, and both must be set before
+                 * executing the callback on this cpu.
+                 */
+
+                if (!cpumask_test_cpu(cpu, data->cpumask))
+                        continue;
+
+                smp_rmb();
+
+                if (atomic_read(&data->refs) == 0)
                         continue;
 
+                func = data->csd.func;                  /* for later warn */
                 data->csd.func(data->csd.info);
 
+                /*
+                 * If the cpu mask is not still set then it enabled interrupts,
+                 * we took another smp interrupt, and executed the function
+                 * twice on this cpu.  In theory that copy decremented refs.
+                 */
+                if (!cpumask_test_and_clear_cpu(cpu, data->cpumask)) {
+                        WARN(1, "%pS enabled interrupts and double executed\n",
+                             func);
+                        continue;
+                }
+
                 refs = atomic_dec_return(&data->refs);
                 WARN_ON(refs < 0);
-                if (!refs) {
-                        raw_spin_lock(&call_function.lock);
-                        list_del_rcu(&data->csd.list);
-                        raw_spin_unlock(&call_function.lock);
-                }
 
                 if (refs)
                         continue;
 
+                WARN_ON(!cpumask_empty(data->cpumask));
+
+                raw_spin_lock(&call_function.lock);
+                list_del_rcu(&data->csd.list);
+                raw_spin_unlock(&call_function.lock);
+
                 csd_unlock(&data->csd);
         }
 
@@ -430,7 +459,7 @@ void smp_call_function_many(const struct cpumask *mask,
          * can't happen.
          */
         WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled()
-                     && !oops_in_progress);
+                     && !oops_in_progress && !early_boot_irqs_disabled);
 
         /* So, what's a CPU they want? Ignoring this one. */
         cpu = cpumask_first_and(mask, cpu_online_mask);
@@ -454,11 +483,21 @@ void smp_call_function_many(const struct cpumask *mask,
 
         data = &__get_cpu_var(cfd_data);
         csd_lock(&data->csd);
+        BUG_ON(atomic_read(&data->refs) || !cpumask_empty(data->cpumask));
 
         data->csd.func = func;
         data->csd.info = info;
         cpumask_and(data->cpumask, mask, cpu_online_mask);
         cpumask_clear_cpu(this_cpu, data->cpumask);
+
+        /*
+         * To ensure the interrupt handler gets an complete view
+         * we order the cpumask and refs writes and order the read
+         * of them in the interrupt handler.  In addition we may
+         * only clear our own cpu bit from the mask.
+         */
+        smp_wmb();
+
         atomic_set(&data->refs, cpumask_weight(data->cpumask));
 
         raw_spin_lock_irqsave(&call_function.lock, flags);
@@ -533,17 +572,20 @@ void ipi_call_unlock_irq(void)
 #endif /* USE_GENERIC_SMP_HELPERS */
 
 /*
- * Call a function on all processors
+ * Call a function on all processors.  May be used during early boot while
+ * early_boot_irqs_disabled is set.  Use local_irq_save/restore() instead
+ * of local_irq_disable/enable().
  */
 int on_each_cpu(void (*func) (void *info), void *info, int wait)
 {
+        unsigned long flags;
         int ret = 0;
 
         preempt_disable();
         ret = smp_call_function(func, info, wait);
-        local_irq_disable();
+        local_irq_save(flags);
         func(info);
-        local_irq_enable();
+        local_irq_restore(flags);
         preempt_enable();
         return ret;
 }
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 3e216e01bbd1..c55ea2433471 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -642,8 +642,7 @@ static void tick_nohz_switch_to_nohz(void)
         }
         local_irq_enable();
 
-        printk(KERN_INFO "Switched to NOHz mode on CPU #%d\n",
-               smp_processor_id());
+        printk(KERN_INFO "Switched to NOHz mode on CPU #%d\n", smp_processor_id());
 }
 
 /*
@@ -795,8 +794,10 @@ void tick_setup_sched_timer(void)
         }
 
 #ifdef CONFIG_NO_HZ
-        if (tick_nohz_enabled)
+        if (tick_nohz_enabled) {
                 ts->nohz_mode = NOHZ_MODE_HIGHRES;
+                printk(KERN_INFO "Switched to NOHz mode on CPU #%d\n", smp_processor_id());
+        }
 #endif
 }
 #endif /* HIGH_RES_TIMERS */
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 5cf8c602b880..92b6e1e12d98 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -453,14 +453,6 @@ void time_hardirqs_off(unsigned long a0, unsigned long a1)
  * Stubs:
  */
 
-void early_boot_irqs_off(void)
-{
-}
-
-void early_boot_irqs_on(void)
-{
-}
-
 void trace_softirqs_on(unsigned long ip)
 {
 }
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 8ee6ec82f88a..11869faa6819 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -768,7 +768,11 @@ static inline void worker_clr_flags(struct worker *worker, unsigned int flags)
 
         worker->flags &= ~flags;
 
-        /* if transitioning out of NOT_RUNNING, increment nr_running */
+        /*
+         * If transitioning out of NOT_RUNNING, increment nr_running.  Note
+         * that the nested NOT_RUNNING is not a noop.  NOT_RUNNING is mask
+         * of multiple flags, not a single flag.
+         */
         if ((flags & WORKER_NOT_RUNNING) && (oflags & WORKER_NOT_RUNNING))
                 if (!(worker->flags & WORKER_NOT_RUNNING))
                         atomic_inc(get_gcwq_nr_running(gcwq->cpu));
@@ -1840,7 +1844,7 @@ __acquires(&gcwq->lock)
         spin_unlock_irq(&gcwq->lock);
 
         work_clear_pending(work);
-        lock_map_acquire(&cwq->wq->lockdep_map);
+        lock_map_acquire_read(&cwq->wq->lockdep_map);
         lock_map_acquire(&lockdep_map);
         trace_workqueue_execute_start(work);
         f(work);
@@ -2384,8 +2388,18 @@ static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr,
         insert_wq_barrier(cwq, barr, work, worker);
         spin_unlock_irq(&gcwq->lock);
 
-        lock_map_acquire(&cwq->wq->lockdep_map);
+        /*
+         * If @max_active is 1 or rescuer is in use, flushing another work
+         * item on the same workqueue may lead to deadlock.  Make sure the
+         * flusher is not running on the same workqueue by verifying write
+         * access.
+         */
+        if (cwq->wq->saved_max_active == 1 || cwq->wq->flags & WQ_RESCUER)
+                lock_map_acquire(&cwq->wq->lockdep_map);
+        else
+                lock_map_acquire_read(&cwq->wq->lockdep_map);
         lock_map_release(&cwq->wq->lockdep_map);
+
         return true;
 already_gone:
         spin_unlock_irq(&gcwq->lock);