18 files changed, 186 insertions, 101 deletions

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 4c62513fe19f..8b729c278b64 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -90,6 +90,14 @@ static DEFINE_MUTEX(cgroup_mutex);
 static DEFINE_MUTEX(cgroup_root_mutex);
 
 /*
+ * cgroup destruction makes heavy use of work items and there can be a lot
+ * of concurrent destructions.  Use a separate workqueue so that cgroup
+ * destruction work items don't end up filling up max_active of system_wq
+ * which may lead to deadlock.
+ */
+static struct workqueue_struct *cgroup_destroy_wq;
+
+/*
  * Generate an array of cgroup subsystem pointers. At boot time, this is
  * populated with the built in subsystems, and modular subsystems are
  * registered after that. The mutable section of this array is protected by
@@ -191,6 +199,7 @@ static void cgroup_destroy_css_killed(struct cgroup *cgrp);
 static int cgroup_destroy_locked(struct cgroup *cgrp);
 static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[],
                               bool is_add);
+static int cgroup_file_release(struct inode *inode, struct file *file);
 
 /**
  * cgroup_css - obtain a cgroup's css for the specified subsystem
@@ -871,7 +880,7 @@ static void cgroup_free_rcu(struct rcu_head *head)
         struct cgroup *cgrp = container_of(head, struct cgroup, rcu_head);
 
         INIT_WORK(&cgrp->destroy_work, cgroup_free_fn);
-        schedule_work(&cgrp->destroy_work);
+        queue_work(cgroup_destroy_wq, &cgrp->destroy_work);
 }
 
 static void cgroup_diput(struct dentry *dentry, struct inode *inode)
@@ -2421,7 +2430,7 @@ static const struct file_operations cgroup_seqfile_operations = {
         .read = seq_read,
         .write = cgroup_file_write,
         .llseek = seq_lseek,
-        .release = single_release,
+        .release = cgroup_file_release,
 };
 
 static int cgroup_file_open(struct inode *inode, struct file *file)
@@ -2482,6 +2491,8 @@ static int cgroup_file_release(struct inode *inode, struct file *file)
                 ret = cft->release(inode, file);
         if (css->ss)
                 css_put(css);
+        if (file->f_op == &cgroup_seqfile_operations)
+                single_release(inode, file);
         return ret;
 }
 
@@ -4249,7 +4260,7 @@ static void css_free_rcu_fn(struct rcu_head *rcu_head)
          * css_put().  dput() requires process context which we don't have.
          */
         INIT_WORK(&css->destroy_work, css_free_work_fn);
-        schedule_work(&css->destroy_work);
+        queue_work(cgroup_destroy_wq, &css->destroy_work);
 }
 
 static void css_release(struct percpu_ref *ref)
@@ -4539,7 +4550,7 @@ static void css_killed_ref_fn(struct percpu_ref *ref)
                 container_of(ref, struct cgroup_subsys_state, refcnt);
 
         INIT_WORK(&css->destroy_work, css_killed_work_fn);
-        schedule_work(&css->destroy_work);
+        queue_work(cgroup_destroy_wq, &css->destroy_work);
 }
 
 /**
@@ -5063,6 +5074,22 @@ out:
         return err;
 }
 
+static int __init cgroup_wq_init(void)
+{
+        /*
+         * There isn't much point in executing destruction path in
+         * parallel.  Good chunk is serialized with cgroup_mutex anyway.
+         * Use 1 for @max_active.
+         *
+         * We would prefer to do this in cgroup_init() above, but that
+         * is called before init_workqueues(): so leave this until after.
+         */
+        cgroup_destroy_wq = alloc_workqueue("cgroup_destroy", 0, 1);
+        BUG_ON(!cgroup_destroy_wq);
+        return 0;
+}
+core_initcall(cgroup_wq_init);
+
 /*
  * proc_cgroup_show()
  *  - Print task's cgroup paths into seq_file, one line for each hierarchy
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 6bf981e13c43..4772034b4b17 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1033,8 +1033,10 @@ static void cpuset_change_task_nodemask(struct task_struct *tsk,
         need_loop = task_has_mempolicy(tsk) ||
                         !nodes_intersects(*newmems, tsk->mems_allowed);
 
-        if (need_loop)
+        if (need_loop) {
+                local_irq_disable();
                 write_seqcount_begin(&tsk->mems_allowed_seq);
+        }
 
         nodes_or(tsk->mems_allowed, tsk->mems_allowed, *newmems);
         mpol_rebind_task(tsk, newmems, MPOL_REBIND_STEP1);
@@ -1042,8 +1044,10 @@ static void cpuset_change_task_nodemask(struct task_struct *tsk,
         mpol_rebind_task(tsk, newmems, MPOL_REBIND_STEP2);
         tsk->mems_allowed = *newmems;
 
-        if (need_loop)
+        if (need_loop) {
                 write_seqcount_end(&tsk->mems_allowed_seq);
+                local_irq_enable();
+        }
 
         task_unlock(tsk);
 }
diff --git a/kernel/events/core.c b/kernel/events/core.c
index d724e7757cd1..72348dc192c1 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -5680,11 +5680,6 @@ static void swevent_hlist_put(struct perf_event *event)
 {
         int cpu;
 
-        if (event->cpu != -1) {
-                swevent_hlist_put_cpu(event, event->cpu);
-                return;
-        }
-
         for_each_possible_cpu(cpu)
                 swevent_hlist_put_cpu(event, cpu);
 }
@@ -5718,9 +5713,6 @@ static int swevent_hlist_get(struct perf_event *event)
         int err;
         int cpu, failed_cpu;
 
-        if (event->cpu != -1)
-                return swevent_hlist_get_cpu(event, event->cpu);
-
         get_online_cpus();
         for_each_possible_cpu(cpu) {
                 err = swevent_hlist_get_cpu(event, cpu);
diff --git a/kernel/extable.c b/kernel/extable.c
index 832cb28105bb..763faf037ec1 100644
--- a/kernel/extable.c
+++ b/kernel/extable.c
@@ -61,7 +61,7 @@ const struct exception_table_entry *search_exception_tables(unsigned long addr)
 static inline int init_kernel_text(unsigned long addr)
 {
         if (addr >= (unsigned long)_sinittext &&
-            addr <= (unsigned long)_einittext)
+            addr < (unsigned long)_einittext)
                 return 1;
         return 0;
 }
@@ -69,7 +69,7 @@ static inline int init_kernel_text(unsigned long addr)
 int core_kernel_text(unsigned long addr)
 {
         if (addr >= (unsigned long)_stext &&
-            addr <= (unsigned long)_etext)
+            addr < (unsigned long)_etext)
                 return 1;
 
         if (system_state == SYSTEM_BOOTING &&
diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c
index cb228bf21760..abcd6ca86cb7 100644
--- a/kernel/irq/pm.c
+++ b/kernel/irq/pm.c
@@ -50,7 +50,7 @@ static void resume_irqs(bool want_early)
                 bool is_early = desc->action &&
                         desc->action->flags & IRQF_EARLY_RESUME;
 
-                if (is_early != want_early)
+                if (!is_early && want_early)
                         continue;
 
                 raw_spin_lock_irqsave(&desc->lock, flags);
diff --git a/kernel/padata.c b/kernel/padata.c
index 07af2c95dcfe..2abd25d79cc8 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -46,6 +46,7 @@ static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index)
 
 static int padata_cpu_hash(struct parallel_data *pd)
 {
+        unsigned int seq_nr;
         int cpu_index;
 
         /*
@@ -53,10 +54,8 @@ static int padata_cpu_hash(struct parallel_data *pd)
          * seq_nr mod. number of cpus in use.
          */
 
-        spin_lock(&pd->seq_lock);
-        cpu_index =  pd->seq_nr % cpumask_weight(pd->cpumask.pcpu);
-        pd->seq_nr++;
-        spin_unlock(&pd->seq_lock);
+        seq_nr = atomic_inc_return(&pd->seq_nr);
+        cpu_index = seq_nr % cpumask_weight(pd->cpumask.pcpu);
 
         return padata_index_to_cpu(pd, cpu_index);
 }
@@ -429,7 +428,7 @@ static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
         padata_init_pqueues(pd);
         padata_init_squeues(pd);
         setup_timer(&pd->timer, padata_reorder_timer, (unsigned long)pd);
-        pd->seq_nr = 0;
+        atomic_set(&pd->seq_nr, -1);
         atomic_set(&pd->reorder_objects, 0);
         atomic_set(&pd->refcnt, 0);
         pd->pinst = pinst;
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 6abb03dff5c0..08a765232432 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -1632,7 +1632,7 @@ module_param(rcu_idle_gp_delay, int, 0644);
 static int rcu_idle_lazy_gp_delay = RCU_IDLE_LAZY_GP_DELAY;
 module_param(rcu_idle_lazy_gp_delay, int, 0644);
 
-extern int tick_nohz_enabled;
+extern int tick_nohz_active;
 
 /*
  * Try to advance callbacks for all flavors of RCU on the current CPU, but
@@ -1729,7 +1729,7 @@ static void rcu_prepare_for_idle(int cpu)
         int tne;
 
         /* Handle nohz enablement switches conservatively. */
-        tne = ACCESS_ONCE(tick_nohz_enabled);
+        tne = ACCESS_ONCE(tick_nohz_active);
         if (tne != rdtp->tick_nohz_enabled_snap) {
                 if (rcu_cpu_has_callbacks(cpu, NULL))
                         invoke_rcu_core(); /* force nohz to see update. */
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index c1808606ee5f..e85cda20ab2b 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2660,6 +2660,7 @@ asmlinkage void __sched notrace preempt_schedule(void)
         } while (need_resched());
 }
 EXPORT_SYMBOL(preempt_schedule);
+#endif /* CONFIG_PREEMPT */
 
 /*
  * this is the entry point to schedule() from kernel preemption
@@ -2693,8 +2694,6 @@ asmlinkage void __sched preempt_schedule_irq(void)
         exception_exit(prev_state);
 }
 
-#endif /* CONFIG_PREEMPT */
-
 int default_wake_function(wait_queue_t *curr, unsigned mode, int wake_flags,
                           void *key)
 {
@@ -4762,7 +4761,7 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd)
                 cpumask_clear_cpu(rq->cpu, old_rd->span);
 
                 /*
-                 * If we dont want to free the old_rt yet then
+                 * If we dont want to free the old_rd yet then
                  * set old_rd to NULL to skip the freeing later
                  * in this function:
                  */
@@ -4910,8 +4909,9 @@ static void update_top_cache_domain(int cpu)
         if (sd) {
                 id = cpumask_first(sched_domain_span(sd));
                 size = cpumask_weight(sched_domain_span(sd));
-                rcu_assign_pointer(per_cpu(sd_busy, cpu), sd->parent);
+                sd = sd->parent; /* sd_busy */
         }
+        rcu_assign_pointer(per_cpu(sd_busy, cpu), sd);
 
         rcu_assign_pointer(per_cpu(sd_llc, cpu), sd);
         per_cpu(sd_llc_size, cpu) = size;
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index e8b652ebe027..fd773ade1a31 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -5379,10 +5379,31 @@ void update_group_power(struct sched_domain *sd, int cpu)
                  */
 
                 for_each_cpu(cpu, sched_group_cpus(sdg)) {
-                        struct sched_group *sg = cpu_rq(cpu)->sd->groups;
+                        struct sched_group_power *sgp;
+                        struct rq *rq = cpu_rq(cpu);
 
-                        power_orig += sg->sgp->power_orig;
-                        power += sg->sgp->power;
+                        /*
+                         * build_sched_domains() -> init_sched_groups_power()
+                         * gets here before we've attached the domains to the
+                         * runqueues.
+                         *
+                         * Use power_of(), which is set irrespective of domains
+                         * in update_cpu_power().
+                         *
+                         * This avoids power/power_orig from being 0 and
+                         * causing divide-by-zero issues on boot.
+                         *
+                         * Runtime updates will correct power_orig.
+                         */
+                        if (unlikely(!rq->sd)) {
+                                power_orig += power_of(cpu);
+                                power += power_of(cpu);
+                                continue;
+                        }
+
+                        sgp = rq->sd->groups->sgp;
+                        power_orig += sgp->power_orig;
+                        power += sgp->power;
                 }
         } else  {
                 /*
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
index 64522ecdfe0e..162b03ab0ad2 100644
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -33,6 +33,21 @@ DEFINE_PER_CPU(struct tick_device, tick_cpu_device);
  */
 ktime_t tick_next_period;
 ktime_t tick_period;
+
+/*
+ * tick_do_timer_cpu is a timer core internal variable which holds the CPU NR
+ * which is responsible for calling do_timer(), i.e. the timekeeping stuff. This
+ * variable has two functions:
+ *
+ * 1) Prevent a thundering herd issue of a gazillion of CPUs trying to grab the
+ *    timekeeping lock all at once. Only the CPU which is assigned to do the
+ *    update is handling it.
+ *
+ * 2) Hand off the duty in the NOHZ idle case by setting the value to
+ *    TICK_DO_TIMER_NONE, i.e. a non existing CPU. So the next cpu which looks
+ *    at it will take over and keep the time keeping alive.  The handover
+ *    procedure also covers cpu hotplug.
+ */
 int tick_do_timer_cpu __read_mostly = TICK_DO_TIMER_BOOT;
 
 /*
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 3612fc77f834..ea20f7d1ac2c 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -361,8 +361,8 @@ void __init tick_nohz_init(void)
 /*
  * NO HZ enabled ?
  */
-int tick_nohz_enabled __read_mostly  = 1;
-
+static int tick_nohz_enabled __read_mostly  = 1;
+int tick_nohz_active  __read_mostly;
 /*
  * Enable / Disable tickless mode
  */
@@ -465,7 +465,7 @@ u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time)
         struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
         ktime_t now, idle;
 
-        if (!tick_nohz_enabled)
+        if (!tick_nohz_active)
                 return -1;
 
         now = ktime_get();
@@ -506,7 +506,7 @@ u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time)
         struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
         ktime_t now, iowait;
 
-        if (!tick_nohz_enabled)
+        if (!tick_nohz_active)
                 return -1;
 
         now = ktime_get();
@@ -711,8 +711,10 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts)
                 return false;
         }
 
-        if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE))
+        if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE)) {
+                ts->sleep_length = (ktime_t) { .tv64 = NSEC_PER_SEC/HZ };
                 return false;
+        }
 
         if (need_resched())
                 return false;
@@ -799,11 +801,6 @@ void tick_nohz_idle_enter(void)
         local_irq_disable();
 
         ts = &__get_cpu_var(tick_cpu_sched);
-        /*
-         * set ts->inidle unconditionally. even if the system did not
-         * switch to nohz mode the cpu frequency governers rely on the
-         * update of the idle time accounting in tick_nohz_start_idle().
-         */
         ts->inidle = 1;
         __tick_nohz_idle_enter(ts);
 
@@ -973,7 +970,7 @@ static void tick_nohz_switch_to_nohz(void)
         struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched);
         ktime_t next;
 
-        if (!tick_nohz_enabled)
+        if (!tick_nohz_active)
                 return;
 
         local_irq_disable();
@@ -981,7 +978,7 @@ static void tick_nohz_switch_to_nohz(void)
                 local_irq_enable();
                 return;
         }
-
+        tick_nohz_active = 1;
         ts->nohz_mode = NOHZ_MODE_LOWRES;
 
         /*
@@ -1139,8 +1136,10 @@ void tick_setup_sched_timer(void)
         }
 
 #ifdef CONFIG_NO_HZ_COMMON
-        if (tick_nohz_enabled)
+        if (tick_nohz_enabled) {
                 ts->nohz_mode = NOHZ_MODE_HIGHRES;
+                tick_nohz_active = 1;
+        }
 #endif
 }
 #endif /* HIGH_RES_TIMERS */
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 3abf53418b67..87b4f00284c9 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -1347,7 +1347,7 @@ static inline void old_vsyscall_fixup(struct timekeeper *tk)
         tk->xtime_nsec -= remainder;
         tk->xtime_nsec += 1ULL << tk->shift;
         tk->ntp_error += remainder << tk->ntp_error_shift;
-
+        tk->ntp_error -= (1ULL << tk->shift) << tk->ntp_error_shift;
 }
 #else
 #define old_vsyscall_fixup(tk)
diff --git a/kernel/timer.c b/kernel/timer.c
index 6582b82fa966..accfd241b9e5 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -1518,9 +1518,8 @@ static int init_timers_cpu(int cpu)
                         /*
                          * The APs use this path later in boot
                          */
-                        base = kmalloc_node(sizeof(*base),
-                                                GFP_KERNEL | __GFP_ZERO,
-                                                cpu_to_node(cpu));
+                        base = kzalloc_node(sizeof(*base), GFP_KERNEL,
+                                            cpu_to_node(cpu));
                         if (!base)
                                 return -ENOMEM;
 
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 22fa55696760..0e9f9eaade2f 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -367,9 +367,6 @@ static int remove_ftrace_list_ops(struct ftrace_ops **list,
 
 static int __register_ftrace_function(struct ftrace_ops *ops)
 {
-        if (unlikely(ftrace_disabled))
-                return -ENODEV;
-
         if (FTRACE_WARN_ON(ops == &global_ops))
                 return -EINVAL;
 
@@ -428,9 +425,6 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
 {
         int ret;
 
-        if (ftrace_disabled)
-                return -ENODEV;
-
         if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED)))
                 return -EBUSY;
 
@@ -2088,10 +2082,15 @@ static void ftrace_startup_enable(int command)
 static int ftrace_startup(struct ftrace_ops *ops, int command)
 {
         bool hash_enable = true;
+        int ret;
 
         if (unlikely(ftrace_disabled))
                 return -ENODEV;
 
+        ret = __register_ftrace_function(ops);
+        if (ret)
+                return ret;
+
         ftrace_start_up++;
         command |= FTRACE_UPDATE_CALLS;
 
@@ -2113,12 +2112,17 @@ static int ftrace_startup(struct ftrace_ops *ops, int command)
         return 0;
 }
 
-static void ftrace_shutdown(struct ftrace_ops *ops, int command)
+static int ftrace_shutdown(struct ftrace_ops *ops, int command)
 {
         bool hash_disable = true;
+        int ret;
 
         if (unlikely(ftrace_disabled))
-                return;
+                return -ENODEV;
+
+        ret = __unregister_ftrace_function(ops);
+        if (ret)
+                return ret;
 
         ftrace_start_up--;
         /*
@@ -2153,9 +2157,10 @@ static void ftrace_shutdown(struct ftrace_ops *ops, int command)
         }
 
         if (!command || !ftrace_enabled)
-                return;
+                return 0;
 
         ftrace_run_update_code(command);
+        return 0;
 }
 
 static void ftrace_startup_sysctl(void)
@@ -3060,16 +3065,13 @@ static void __enable_ftrace_function_probe(void)
         if (i == FTRACE_FUNC_HASHSIZE)
                 return;
 
-        ret = __register_ftrace_function(&trace_probe_ops);
-        if (!ret)
-                ret = ftrace_startup(&trace_probe_ops, 0);
+        ret = ftrace_startup(&trace_probe_ops, 0);
 
         ftrace_probe_registered = 1;
 }
 
 static void __disable_ftrace_function_probe(void)
 {
-        int ret;
         int i;
 
         if (!ftrace_probe_registered)
@@ -3082,9 +3084,7 @@ static void __disable_ftrace_function_probe(void)
         }
 
         /* no more funcs left */
-        ret = __unregister_ftrace_function(&trace_probe_ops);
-        if (!ret)
-                ftrace_shutdown(&trace_probe_ops, 0);
+        ftrace_shutdown(&trace_probe_ops, 0);
 
         ftrace_probe_registered = 0;
 }
@@ -4366,12 +4366,15 @@ core_initcall(ftrace_nodyn_init);
 static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; }
 static inline void ftrace_startup_enable(int command) { }
 /* Keep as macros so we do not need to define the commands */
-# define ftrace_startup(ops, command)                   \
-        ({                                              \
-                (ops)->flags |= FTRACE_OPS_FL_ENABLED;  \
-                0;                                      \
+# define ftrace_startup(ops, command)                                   \
+        ({                                                              \
+                int ___ret = __register_ftrace_function(ops);           \
+                if (!___ret)                                            \
+                        (ops)->flags |= FTRACE_OPS_FL_ENABLED;          \
+                ___ret;                                                 \
         })
-# define ftrace_shutdown(ops, command)  do { } while (0)
+# define ftrace_shutdown(ops, command) __unregister_ftrace_function(ops)
+
 # define ftrace_startup_sysctl()        do { } while (0)
 # define ftrace_shutdown_sysctl()       do { } while (0)
 
@@ -4780,9 +4783,7 @@ int register_ftrace_function(struct ftrace_ops *ops)
 
         mutex_lock(&ftrace_lock);
 
-        ret = __register_ftrace_function(ops);
-        if (!ret)
-                ret = ftrace_startup(ops, 0);
+        ret = ftrace_startup(ops, 0);
 
         mutex_unlock(&ftrace_lock);
 
@@ -4801,9 +4802,7 @@ int unregister_ftrace_function(struct ftrace_ops *ops)
         int ret;
 
         mutex_lock(&ftrace_lock);
-        ret = __unregister_ftrace_function(ops);
-        if (!ret)
-                ftrace_shutdown(ops, 0);
+        ret = ftrace_shutdown(ops, 0);
         mutex_unlock(&ftrace_lock);
 
         return ret;
@@ -4997,6 +4996,13 @@ ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state,
         return NOTIFY_DONE;
 }
 
+/* Just a place holder for function graph */
+static struct ftrace_ops fgraph_ops __read_mostly = {
+        .func           = ftrace_stub,
+        .flags          = FTRACE_OPS_FL_STUB | FTRACE_OPS_FL_GLOBAL |
+                                FTRACE_OPS_FL_RECURSION_SAFE,
+};
+
 int register_ftrace_graph(trace_func_graph_ret_t retfunc,
                         trace_func_graph_ent_t entryfunc)
 {
@@ -5023,7 +5029,7 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
         ftrace_graph_return = retfunc;
         ftrace_graph_entry = entryfunc;
 
-        ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET);
+        ret = ftrace_startup(&fgraph_ops, FTRACE_START_FUNC_RET);
 
 out:
         mutex_unlock(&ftrace_lock);
@@ -5040,7 +5046,7 @@ void unregister_ftrace_graph(void)
         ftrace_graph_active--;
         ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
         ftrace_graph_entry = ftrace_graph_entry_stub;
-        ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET);
+        ftrace_shutdown(&fgraph_ops, FTRACE_STOP_FUNC_RET);
         unregister_pm_notifier(&ftrace_suspend_notifier);
         unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);
 
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index 78e27e3b52ac..e854f420e033 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -24,6 +24,12 @@ static int	total_ref_count;
 static int perf_trace_event_perm(struct ftrace_event_call *tp_event,
                                  struct perf_event *p_event)
 {
+        if (tp_event->perf_perm) {
+                int ret = tp_event->perf_perm(tp_event, p_event);
+                if (ret)
+                        return ret;
+        }
+
         /* The ftrace function trace is allowed only for root. */
         if (ftrace_event_is_function(tp_event) &&
             perf_paranoid_tracepoint_raw() && !capable(CAP_SYS_ADMIN))
@@ -173,7 +179,7 @@ static int perf_trace_event_init(struct ftrace_event_call *tp_event,
 int perf_trace_init(struct perf_event *p_event)
 {
         struct ftrace_event_call *tp_event;
-        int event_id = p_event->attr.config;
+        u64 event_id = p_event->attr.config;
         int ret = -EINVAL;
 
         mutex_lock(&event_mutex);
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index f919a2e21bf3..a11800ae96de 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2314,6 +2314,9 @@ int event_trace_del_tracer(struct trace_array *tr)
         /* Disable any running events */
         __ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0);
 
+        /* Access to events are within rcu_read_lock_sched() */
+        synchronize_sched();
+
         down_write(&trace_event_sem);
         __trace_remove_event_dirs(tr);
         debugfs_remove_recursive(tr->event_dir);
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index e4b6d11bdf78..ea90eb5f6f17 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -431,11 +431,6 @@ static void unreg_event_syscall_enter(struct ftrace_event_file *file,
         if (!tr->sys_refcount_enter)
                 unregister_trace_sys_enter(ftrace_syscall_enter, tr);
         mutex_unlock(&syscall_trace_lock);
-        /*
-         * Callers expect the event to be completely disabled on
-         * return, so wait for current handlers to finish.
-         */
-        synchronize_sched();
 }
 
 static int reg_event_syscall_exit(struct ftrace_event_file *file,
@@ -474,11 +469,6 @@ static void unreg_event_syscall_exit(struct ftrace_event_file *file,
         if (!tr->sys_refcount_exit)
                 unregister_trace_sys_exit(ftrace_syscall_exit, tr);
         mutex_unlock(&syscall_trace_lock);
-        /*
-         * Callers expect the event to be completely disabled on
-         * return, so wait for current handlers to finish.
-         */
-        synchronize_sched();
 }
 
 static int __init init_syscall_trace(struct ftrace_event_call *call)
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 987293d03ebc..c66912be990f 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -305,6 +305,9 @@ static DEFINE_HASHTABLE(unbound_pool_hash, UNBOUND_POOL_HASH_ORDER);
 /* I: attributes used when instantiating standard unbound pools on demand */
 static struct workqueue_attrs *unbound_std_wq_attrs[NR_STD_WORKER_POOLS];
 
+/* I: attributes used when instantiating ordered pools on demand */
+static struct workqueue_attrs *ordered_wq_attrs[NR_STD_WORKER_POOLS];
+
 struct workqueue_struct *system_wq __read_mostly;
 EXPORT_SYMBOL(system_wq);
 struct workqueue_struct *system_highpri_wq __read_mostly;
@@ -518,14 +521,21 @@ static inline void debug_work_activate(struct work_struct *work) { }
 static inline void debug_work_deactivate(struct work_struct *work) { }
 #endif
 
-/* allocate ID and assign it to @pool */
+/**
+ * worker_pool_assign_id - allocate ID and assing it to @pool
+ * @pool: the pool pointer of interest
+ *
+ * Returns 0 if ID in [0, WORK_OFFQ_POOL_NONE) is allocated and assigned
+ * successfully, -errno on failure.
+ */
 static int worker_pool_assign_id(struct worker_pool *pool)
 {
         int ret;
 
         lockdep_assert_held(&wq_pool_mutex);
 
-        ret = idr_alloc(&worker_pool_idr, pool, 0, 0, GFP_KERNEL);
+        ret = idr_alloc(&worker_pool_idr, pool, 0, WORK_OFFQ_POOL_NONE,
+                        GFP_KERNEL);
         if (ret >= 0) {
                 pool->id = ret;
                 return 0;
@@ -1320,7 +1330,7 @@ static void __queue_work(int cpu, struct workqueue_struct *wq,
 
         debug_work_activate(work);
 
-        /* if dying, only works from the same workqueue are allowed */
+        /* if draining, only works from the same workqueue are allowed */
         if (unlikely(wq->flags & __WQ_DRAINING) &&
             WARN_ON_ONCE(!is_chained_work(wq)))
                 return;
@@ -1736,16 +1746,17 @@ static struct worker *create_worker(struct worker_pool *pool)
         if (IS_ERR(worker->task))
                 goto fail;
 
+        set_user_nice(worker->task, pool->attrs->nice);
+
+        /* prevent userland from meddling with cpumask of workqueue workers */
+        worker->task->flags |= PF_NO_SETAFFINITY;
+
         /*
          * set_cpus_allowed_ptr() will fail if the cpumask doesn't have any
          * online CPUs.  It'll be re-applied when any of the CPUs come up.
          */
-        set_user_nice(worker->task, pool->attrs->nice);
         set_cpus_allowed_ptr(worker->task, pool->attrs->cpumask);
 
-        /* prevent userland from meddling with cpumask of workqueue workers */
-        worker->task->flags |= PF_NO_SETAFFINITY;
-
         /*
          * The caller is responsible for ensuring %POOL_DISASSOCIATED
          * remains stable across this function.  See the comments above the
@@ -4106,7 +4117,7 @@ out_unlock:
 static int alloc_and_link_pwqs(struct workqueue_struct *wq)
 {
         bool highpri = wq->flags & WQ_HIGHPRI;
-        int cpu;
+        int cpu, ret;
 
         if (!(wq->flags & WQ_UNBOUND)) {
                 wq->cpu_pwqs = alloc_percpu(struct pool_workqueue);
@@ -4126,6 +4137,13 @@ static int alloc_and_link_pwqs(struct workqueue_struct *wq)
                         mutex_unlock(&wq->mutex);
                 }
                 return 0;
+        } else if (wq->flags & __WQ_ORDERED) {
+                ret = apply_workqueue_attrs(wq, ordered_wq_attrs[highpri]);
+                /* there should only be single pwq for ordering guarantee */
+                WARN(!ret && (wq->pwqs.next != &wq->dfl_pwq->pwqs_node ||
+                              wq->pwqs.prev != &wq->dfl_pwq->pwqs_node),
+                     "ordering guarantee broken for workqueue %s\n", wq->name);
+                return ret;
         } else {
                 return apply_workqueue_attrs(wq, unbound_std_wq_attrs[highpri]);
         }
@@ -5009,10 +5027,6 @@ static int __init init_workqueues(void)
         int std_nice[NR_STD_WORKER_POOLS] = { 0, HIGHPRI_NICE_LEVEL };
         int i, cpu;
 
-        /* make sure we have enough bits for OFFQ pool ID */
-        BUILD_BUG_ON((1LU << (BITS_PER_LONG - WORK_OFFQ_POOL_SHIFT)) <
-                     WORK_CPU_END * NR_STD_WORKER_POOLS);
-
         WARN_ON(__alignof__(struct pool_workqueue) < __alignof__(long long));
 
         pwq_cache = KMEM_CACHE(pool_workqueue, SLAB_PANIC);
@@ -5051,13 +5065,23 @@ static int __init init_workqueues(void)
                 }
         }
 
-        /* create default unbound wq attrs */
+        /* create default unbound and ordered wq attrs */
         for (i = 0; i < NR_STD_WORKER_POOLS; i++) {
                 struct workqueue_attrs *attrs;
 
                 BUG_ON(!(attrs = alloc_workqueue_attrs(GFP_KERNEL)));
                 attrs->nice = std_nice[i];
                 unbound_std_wq_attrs[i] = attrs;
+
+                /*
+                 * An ordered wq should have only one pwq as ordering is
+                 * guaranteed by max_active which is enforced by pwqs.
+                 * Turn off NUMA so that dfl_pwq is used for all nodes.
+                 */
+                BUG_ON(!(attrs = alloc_workqueue_attrs(GFP_KERNEL)));
+                attrs->nice = std_nice[i];
+                attrs->no_numa = true;
+                ordered_wq_attrs[i] = attrs;
         }
 
         system_wq = alloc_workqueue("events", 0, 0);