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

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (184 commits)
  perf probe: Clean up probe_point_lazy_walker() return value
  tracing: Fix irqoff selftest expanding max buffer
  tracing: Align 4 byte ints together in struct tracer
  tracing: Export trace_set_clr_event()
  tracing: Explain about unstable clock on resume with ring buffer warning
  ftrace/graph: Trace function entry before updating index
  ftrace: Add .ref.text as one of the safe areas to trace
  tracing: Adjust conditional expression latency formatting.
  tracing: Fix event alignment: skb:kfree_skb
  tracing: Fix event alignment: mce:mce_record
  tracing: Fix event alignment: kvm:kvm_hv_hypercall
  tracing: Fix event alignment: module:module_request
  tracing: Fix event alignment: ftrace:context_switch and ftrace:wakeup
  tracing: Remove lock_depth from event entry
  perf header: Stop using 'self'
  perf session: Use evlist/evsel for managing perf.data attributes
  perf top: Don't let events to eat up whole header line
  perf top: Fix events overflow in top command
  ring-buffer: Remove unused #include <linux/trace_irq.h>
  tracing: Add an 'overwrite' trace_option.
  ...

15 files changed, 1904 insertions, 478 deletions

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index b24d7027b83..95362d15128 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -4230,20 +4230,8 @@ void cgroup_post_fork(struct task_struct *child)
  */
 void cgroup_exit(struct task_struct *tsk, int run_callbacks)
 {
-	int i;
 	struct css_set *cg;
-
-	if (run_callbacks && need_forkexit_callback) {
-		/*
-		 * modular subsystems can't use callbacks, so no need to lock
-		 * the subsys array
-		 */
-		for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
-			struct cgroup_subsys *ss = subsys[i];
-			if (ss->exit)
-				ss->exit(ss, tsk);
-		}
-	}
+	int i;
 
 	/*
 	 * Unlink from the css_set task list if necessary.
@@ -4261,7 +4249,24 @@ void cgroup_exit(struct task_struct *tsk, int run_callbacks)
 	task_lock(tsk);
 	cg = tsk->cgroups;
 	tsk->cgroups = &init_css_set;
+
+	if (run_callbacks && need_forkexit_callback) {
+		/*
+		 * modular subsystems can't use callbacks, so no need to lock
+		 * the subsys array
+		 */
+		for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
+			struct cgroup_subsys *ss = subsys[i];
+			if (ss->exit) {
+				struct cgroup *old_cgrp =
+					rcu_dereference_raw(cg->subsys[i])->cgroup;
+				struct cgroup *cgrp = task_cgroup(tsk, i);
+				ss->exit(ss, cgrp, old_cgrp, tsk);
+			}
+		}
+	}
 	task_unlock(tsk);
+
 	if (cg)
 		put_css_set_taskexit(cg);
 }
@@ -4813,6 +4818,29 @@ css_get_next(struct cgroup_subsys *ss, int id,
 	return ret;
 }
 
+/*
+ * get corresponding css from file open on cgroupfs directory
+ */
+struct cgroup_subsys_state *cgroup_css_from_dir(struct file *f, int id)
+{
+	struct cgroup *cgrp;
+	struct inode *inode;
+	struct cgroup_subsys_state *css;
+
+	inode = f->f_dentry->d_inode;
+	/* check in cgroup filesystem dir */
+	if (inode->i_op != &cgroup_dir_inode_operations)
+		return ERR_PTR(-EBADF);
+
+	if (id < 0 || id >= CGROUP_SUBSYS_COUNT)
+		return ERR_PTR(-EINVAL);
+
+	/* get cgroup */
+	cgrp = __d_cgrp(f->f_dentry);
+	css = cgrp->subsys[id];
+	return css ? css : ERR_PTR(-ENOENT);
+}
+
 #ifdef CONFIG_CGROUP_DEBUG
 static struct cgroup_subsys_state *debug_create(struct cgroup_subsys *ss,
 						   struct cgroup *cont)
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 656222fcf76..ed253aa24ba 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -38,13 +38,96 @@
 
 #include <asm/irq_regs.h>
 
+struct remote_function_call {
+	struct task_struct *p;
+	int (*func)(void *info);
+	void *info;
+	int ret;
+};
+
+static void remote_function(void *data)
+{
+	struct remote_function_call *tfc = data;
+	struct task_struct *p = tfc->p;
+
+	if (p) {
+		tfc->ret = -EAGAIN;
+		if (task_cpu(p) != smp_processor_id() || !task_curr(p))
+			return;
+	}
+
+	tfc->ret = tfc->func(tfc->info);
+}
+
+/**
+ * task_function_call - call a function on the cpu on which a task runs
+ * @p:		the task to evaluate
+ * @func:	the function to be called
+ * @info:	the function call argument
+ *
+ * Calls the function @func when the task is currently running. This might
+ * be on the current CPU, which just calls the function directly
+ *
+ * returns: @func return value, or
+ *	    -ESRCH  - when the process isn't running
+ *	    -EAGAIN - when the process moved away
+ */
+static int
+task_function_call(struct task_struct *p, int (*func) (void *info), void *info)
+{
+	struct remote_function_call data = {
+		.p = p,
+		.func = func,
+		.info = info,
+		.ret = -ESRCH, /* No such (running) process */
+	};
+
+	if (task_curr(p))
+		smp_call_function_single(task_cpu(p), remote_function, &data, 1);
+
+	return data.ret;
+}
+
+/**
+ * cpu_function_call - call a function on the cpu
+ * @func:	the function to be called
+ * @info:	the function call argument
+ *
+ * Calls the function @func on the remote cpu.
+ *
+ * returns: @func return value or -ENXIO when the cpu is offline
+ */
+static int cpu_function_call(int cpu, int (*func) (void *info), void *info)
+{
+	struct remote_function_call data = {
+		.p = NULL,
+		.func = func,
+		.info = info,
+		.ret = -ENXIO, /* No such CPU */
+	};
+
+	smp_call_function_single(cpu, remote_function, &data, 1);
+
+	return data.ret;
+}
+
+#define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\
+		       PERF_FLAG_FD_OUTPUT  |\
+		       PERF_FLAG_PID_CGROUP)
+
 enum event_type_t {
 	EVENT_FLEXIBLE = 0x1,
 	EVENT_PINNED = 0x2,
 	EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED,
 };
 
-atomic_t perf_task_events __read_mostly;
+/*
+ * perf_sched_events : >0 events exist
+ * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu
+ */
+atomic_t perf_sched_events __read_mostly;
+static DEFINE_PER_CPU(atomic_t, perf_cgroup_events);
+
 static atomic_t nr_mmap_events __read_mostly;
 static atomic_t nr_comm_events __read_mostly;
 static atomic_t nr_task_events __read_mostly;
@@ -67,7 +150,24 @@ int sysctl_perf_event_mlock __read_mostly = 512; /* 'free' kb per user */
 /*
  * max perf event sample rate
  */
-int sysctl_perf_event_sample_rate __read_mostly = 100000;
+#define DEFAULT_MAX_SAMPLE_RATE 100000
+int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE;
+static int max_samples_per_tick __read_mostly =
+	DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ);
+
+int perf_proc_update_handler(struct ctl_table *table, int write,
+		void __user *buffer, size_t *lenp,
+		loff_t *ppos)
+{
+	int ret = proc_dointvec(table, write, buffer, lenp, ppos);
+
+	if (ret || !write)
+		return ret;
+
+	max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ);
+
+	return 0;
+}
 
 static atomic64_t perf_event_id;
 
@@ -75,7 +175,11 @@ static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx,
 			      enum event_type_t event_type);
 
 static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx,
-			     enum event_type_t event_type);
+			     enum event_type_t event_type,
+			     struct task_struct *task);
+
+static void update_context_time(struct perf_event_context *ctx);
+static u64 perf_event_time(struct perf_event *event);
 
 void __weak perf_event_print_debug(void)	{ }
 
@@ -89,6 +193,360 @@ static inline u64 perf_clock(void)
 	return local_clock();
 }
 
+static inline struct perf_cpu_context *
+__get_cpu_context(struct perf_event_context *ctx)
+{
+	return this_cpu_ptr(ctx->pmu->pmu_cpu_context);
+}
+
+#ifdef CONFIG_CGROUP_PERF
+
+/*
+ * Must ensure cgroup is pinned (css_get) before calling
+ * this function. In other words, we cannot call this function
+ * if there is no cgroup event for the current CPU context.
+ */
+static inline struct perf_cgroup *
+perf_cgroup_from_task(struct task_struct *task)
+{
+	return container_of(task_subsys_state(task, perf_subsys_id),
+			struct perf_cgroup, css);
+}
+
+static inline bool
+perf_cgroup_match(struct perf_event *event)
+{
+	struct perf_event_context *ctx = event->ctx;
+	struct perf_cpu_context *cpuctx = __get_cpu_context(ctx);
+
+	return !event->cgrp || event->cgrp == cpuctx->cgrp;
+}
+
+static inline void perf_get_cgroup(struct perf_event *event)
+{
+	css_get(&event->cgrp->css);
+}
+
+static inline void perf_put_cgroup(struct perf_event *event)
+{
+	css_put(&event->cgrp->css);
+}
+
+static inline void perf_detach_cgroup(struct perf_event *event)
+{
+	perf_put_cgroup(event);
+	event->cgrp = NULL;
+}
+
+static inline int is_cgroup_event(struct perf_event *event)
+{
+	return event->cgrp != NULL;
+}
+
+static inline u64 perf_cgroup_event_time(struct perf_event *event)
+{
+	struct perf_cgroup_info *t;
+
+	t = per_cpu_ptr(event->cgrp->info, event->cpu);
+	return t->time;
+}
+
+static inline void __update_cgrp_time(struct perf_cgroup *cgrp)
+{
+	struct perf_cgroup_info *info;
+	u64 now;
+
+	now = perf_clock();
+
+	info = this_cpu_ptr(cgrp->info);
+
+	info->time += now - info->timestamp;
+	info->timestamp = now;
+}
+
+static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx)
+{
+	struct perf_cgroup *cgrp_out = cpuctx->cgrp;
+	if (cgrp_out)
+		__update_cgrp_time(cgrp_out);
+}
+
+static inline void update_cgrp_time_from_event(struct perf_event *event)
+{
+	struct perf_cgroup *cgrp;
+
+	/*
+	 * ensure we access cgroup data only when needed and
+	 * when we know the cgroup is pinned (css_get)
+	 */
+	if (!is_cgroup_event(event))
+		return;
+
+	cgrp = perf_cgroup_from_task(current);
+	/*
+	 * Do not update time when cgroup is not active
+	 */
+	if (cgrp == event->cgrp)
+		__update_cgrp_time(event->cgrp);
+}
+
+static inline void
+perf_cgroup_set_timestamp(struct task_struct *task,
+			  struct perf_event_context *ctx)
+{
+	struct perf_cgroup *cgrp;
+	struct perf_cgroup_info *info;
+
+	/*
+	 * ctx->lock held by caller
+	 * ensure we do not access cgroup data
+	 * unless we have the cgroup pinned (css_get)
+	 */
+	if (!task || !ctx->nr_cgroups)
+		return;
+
+	cgrp = perf_cgroup_from_task(task);
+	info = this_cpu_ptr(cgrp->info);
+	info->timestamp = ctx->timestamp;
+}
+
+#define PERF_CGROUP_SWOUT	0x1 /* cgroup switch out every event */
+#define PERF_CGROUP_SWIN	0x2 /* cgroup switch in events based on task */
+
+/*
+ * reschedule events based on the cgroup constraint of task.
+ *
+ * mode SWOUT : schedule out everything
+ * mode SWIN : schedule in based on cgroup for next
+ */
+void perf_cgroup_switch(struct task_struct *task, int mode)
+{
+	struct perf_cpu_context *cpuctx;
+	struct pmu *pmu;
+	unsigned long flags;
+
+	/*
+	 * disable interrupts to avoid geting nr_cgroup
+	 * changes via __perf_event_disable(). Also
+	 * avoids preemption.
+	 */
+	local_irq_save(flags);
+
+	/*
+	 * we reschedule only in the presence of cgroup
+	 * constrained events.
+	 */
+	rcu_read_lock();
+
+	list_for_each_entry_rcu(pmu, &pmus, entry) {
+
+		cpuctx = this_cpu_ptr(pmu->pmu_cpu_context);
+
+		perf_pmu_disable(cpuctx->ctx.pmu);
+
+		/*
+		 * perf_cgroup_events says at least one
+		 * context on this CPU has cgroup events.
+		 *
+		 * ctx->nr_cgroups reports the number of cgroup
+		 * events for a context.
+		 */
+		if (cpuctx->ctx.nr_cgroups > 0) {
+
+			if (mode & PERF_CGROUP_SWOUT) {
+				cpu_ctx_sched_out(cpuctx, EVENT_ALL);
+				/*
+				 * must not be done before ctxswout due
+				 * to event_filter_match() in event_sched_out()
+				 */
+				cpuctx->cgrp = NULL;
+			}
+
+			if (mode & PERF_CGROUP_SWIN) {
+				/* set cgrp before ctxsw in to
+				 * allow event_filter_match() to not
+				 * have to pass task around
+				 */
+				cpuctx->cgrp = perf_cgroup_from_task(task);
+				cpu_ctx_sched_in(cpuctx, EVENT_ALL, task);
+			}
+		}
+
+		perf_pmu_enable(cpuctx->ctx.pmu);
+	}
+
+	rcu_read_unlock();
+
+	local_irq_restore(flags);
+}
+
+static inline void perf_cgroup_sched_out(struct task_struct *task)
+{
+	perf_cgroup_switch(task, PERF_CGROUP_SWOUT);
+}
+
+static inline void perf_cgroup_sched_in(struct task_struct *task)
+{
+	perf_cgroup_switch(task, PERF_CGROUP_SWIN);
+}
+
+static inline int perf_cgroup_connect(int fd, struct perf_event *event,
+				      struct perf_event_attr *attr,
+				      struct perf_event *group_leader)
+{
+	struct perf_cgroup *cgrp;
+	struct cgroup_subsys_state *css;
+	struct file *file;
+	int ret = 0, fput_needed;
+
+	file = fget_light(fd, &fput_needed);
+	if (!file)
+		return -EBADF;
+
+	css = cgroup_css_from_dir(file, perf_subsys_id);
+	if (IS_ERR(css)) {
+		ret = PTR_ERR(css);
+		goto out;
+	}
+
+	cgrp = container_of(css, struct perf_cgroup, css);
+	event->cgrp = cgrp;
+
+	/* must be done before we fput() the file */
+	perf_get_cgroup(event);
+
+	/*
+	 * all events in a group must monitor
+	 * the same cgroup because a task belongs
+	 * to only one perf cgroup at a time
+	 */
+	if (group_leader && group_leader->cgrp != cgrp) {
+		perf_detach_cgroup(event);
+		ret = -EINVAL;
+	}
+out:
+	fput_light(file, fput_needed);
+	return ret;
+}
+
+static inline void
+perf_cgroup_set_shadow_time(struct perf_event *event, u64 now)
+{
+	struct perf_cgroup_info *t;
+	t = per_cpu_ptr(event->cgrp->info, event->cpu);
+	event->shadow_ctx_time = now - t->timestamp;
+}
+
+static inline void
+perf_cgroup_defer_enabled(struct perf_event *event)
+{
+	/*
+	 * when the current task's perf cgroup does not match
+	 * the event's, we need to remember to call the
+	 * perf_mark_enable() function the first time a task with
+	 * a matching perf cgroup is scheduled in.
+	 */
+	if (is_cgroup_event(event) && !perf_cgroup_match(event))
+		event->cgrp_defer_enabled = 1;
+}
+
+static inline void
+perf_cgroup_mark_enabled(struct perf_event *event,
+			 struct perf_event_context *ctx)
+{
+	struct perf_event *sub;
+	u64 tstamp = perf_event_time(event);
+
+	if (!event->cgrp_defer_enabled)
+		return;
+
+	event->cgrp_defer_enabled = 0;
+
+	event->tstamp_enabled = tstamp - event->total_time_enabled;
+	list_for_each_entry(sub, &event->sibling_list, group_entry) {
+		if (sub->state >= PERF_EVENT_STATE_INACTIVE) {
+			sub->tstamp_enabled = tstamp - sub->total_time_enabled;
+			sub->cgrp_defer_enabled = 0;
+		}
+	}
+}
+#else /* !CONFIG_CGROUP_PERF */
+
+static inline bool
+perf_cgroup_match(struct perf_event *event)
+{
+	return true;
+}
+
+static inline void perf_detach_cgroup(struct perf_event *event)
+{}
+
+static inline int is_cgroup_event(struct perf_event *event)
+{
+	return 0;
+}
+
+static inline u64 perf_cgroup_event_cgrp_time(struct perf_event *event)
+{
+	return 0;
+}
+
+static inline void update_cgrp_time_from_event(struct perf_event *event)
+{
+}
+
+static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx)
+{
+}
+
+static inline void perf_cgroup_sched_out(struct task_struct *task)
+{
+}
+
+static inline void perf_cgroup_sched_in(struct task_struct *task)
+{
+}
+
+static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event,
+				      struct perf_event_attr *attr,
+				      struct perf_event *group_leader)
+{
+	return -EINVAL;
+}
+
+static inline void
+perf_cgroup_set_timestamp(struct task_struct *task,
+			  struct perf_event_context *ctx)
+{
+}
+
+void
+perf_cgroup_switch(struct task_struct *task, struct task_struct *next)
+{
+}
+
+static inline void
+perf_cgroup_set_shadow_time(struct perf_event *event, u64 now)
+{
+}
+
+static inline u64 perf_cgroup_event_time(struct perf_event *event)
+{
+	return 0;
+}
+
+static inline void
+perf_cgroup_defer_enabled(struct perf_event *event)
+{
+}
+
+static inline void
+perf_cgroup_mark_enabled(struct perf_event *event,
+			 struct perf_event_context *ctx)
+{
+}
+#endif
+
 void perf_pmu_disable(struct pmu *pmu)
 {
 	int *count = this_cpu_ptr(pmu->pmu_disable_count);
@@ -254,7 +712,6 @@ static void perf_unpin_context(struct perf_event_context *ctx)
 	raw_spin_lock_irqsave(&ctx->lock, flags);
 	--ctx->pin_count;
 	raw_spin_unlock_irqrestore(&ctx->lock, flags);
-	put_ctx(ctx);
 }
 
 /*
@@ -271,6 +728,10 @@ static void update_context_time(struct perf_event_context *ctx)
 static u64 perf_event_time(struct perf_event *event)
 {
 	struct perf_event_context *ctx = event->ctx;
+
+	if (is_cgroup_event(event))
+		return perf_cgroup_event_time(event);
+
 	return ctx ? ctx->time : 0;
 }
 
@@ -285,9 +746,20 @@ static void update_event_times(struct perf_event *event)
 	if (event->state < PERF_EVENT_STATE_INACTIVE ||
 	    event->group_leader->state < PERF_EVENT_STATE_INACTIVE)
 		return;
-
-	if (ctx->is_active)
+	/*
+	 * in cgroup mode, time_enabled represents
+	 * the time the event was enabled AND active
+	 * tasks were in the monitored cgroup. This is
+	 * independent of the activity of the context as
+	 * there may be a mix of cgroup and non-cgroup events.
+	 *
+	 * That is why we treat cgroup events differently
+	 * here.
+	 */
+	if (is_cgroup_event(event))
 		run_end = perf_event_time(event);
+	else if (ctx->is_active)
+		run_end = ctx->time;
 	else
 		run_end = event->tstamp_stopped;
 
@@ -299,6 +771,7 @@ static void update_event_times(struct perf_event *event)
 		run_end = perf_event_time(event);
 
 	event->total_time_running = run_end - event->tstamp_running;
+
 }
 
 /*
@@ -347,6 +820,9 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx)
 		list_add_tail(&event->group_entry, list);
 	}
 
+	if (is_cgroup_event(event))
+		ctx->nr_cgroups++;
+
 	list_add_rcu(&event->event_entry, &ctx->event_list);
 	if (!ctx->nr_events)
 		perf_pmu_rotate_start(ctx->pmu);
@@ -473,6 +949,9 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx)
 
 	event->attach_state &= ~PERF_ATTACH_CONTEXT;
 
+	if (is_cgroup_event(event))
+		ctx->nr_cgroups--;
+
 	ctx->nr_events--;
 	if (event->attr.inherit_stat)
 		ctx->nr_stat--;
@@ -544,7 +1023,8 @@ out:
 static inline int
 event_filter_match(struct perf_event *event)
 {
-	return event->cpu == -1 || event->cpu == smp_processor_id();
+	return (event->cpu == -1 || event->cpu == smp_processor_id())
+	    && perf_cgroup_match(event);
 }
 
 static void
@@ -562,7 +1042,7 @@ event_sched_out(struct perf_event *event,
 	 */
 	if (event->state == PERF_EVENT_STATE_INACTIVE
 	    && !event_filter_match(event)) {
-		delta = ctx->time - event->tstamp_stopped;
+		delta = tstamp - event->tstamp_stopped;
 		event->tstamp_running += delta;
 		event->tstamp_stopped = tstamp;
 	}
@@ -606,47 +1086,30 @@ group_sched_out(struct perf_event *group_event,
 		cpuctx->exclusive = 0;
 }
 
-static inline struct perf_cpu_context *
-__get_cpu_context(struct perf_event_context *ctx)
-{
-	return this_cpu_ptr(ctx->pmu->pmu_cpu_context);
-}
-
 /*
  * Cross CPU call to remove a performance event
  *
  * We disable the event on the hardware level first. After that we
  * remove it from the context list.
  */
-static void __perf_event_remove_from_context(void *info)
+static int __perf_remove_from_context(void *info)
 {
 	struct perf_event *event = info;
 	struct perf_event_context *ctx = event->ctx;
 	struct perf_cpu_context *cpuctx = __get_cpu_context(ctx);
 
-	/*
-	 * If this is a task context, we need to check whether it is
-	 * the current task context of this cpu. If not it has been
-	 * scheduled out before the smp call arrived.
-	 */
-	if (ctx->task && cpuctx->task_ctx != ctx)
-		return;
-
 	raw_spin_lock(&ctx->lock);
-
 	event_sched_out(event, cpuctx, ctx);
-
 	list_del_event(event, ctx);
-
 	raw_spin_unlock(&ctx->lock);
+
+	return 0;
 }
 
 
 /*
  * Remove the event from a task's (or a CPU's) list of events.
  *
- * Must be called with ctx->mutex held.
- *
  * CPU events are removed with a smp call. For task events we only
  * call when the task is on a CPU.
  *
@@ -657,49 +1120,48 @@ static void __perf_event_remove_from_context(void *info)
  * When called from perf_event_exit_task, it's OK because the
  * context has been detached from its task.
  */
-static void perf_event_remove_from_context(struct perf_event *event)
+static void perf_remove_from_context(struct perf_event *event)
 {
 	struct perf_event_context *ctx = event->ctx;
 	struct task_struct *task = ctx->task;
 
+	lockdep_assert_held(&ctx->mutex);
+
 	if (!task) {
 		/*
 		 * Per cpu events are removed via an smp call and
 		 * the removal is always successful.
 		 */
-		smp_call_function_single(event->cpu,
-					 __perf_event_remove_from_context,
-					 event, 1);
+		cpu_function_call(event->cpu, __perf_remove_from_context, event);
 		return;
 	}
 
 retry:
-	task_oncpu_function_call(task, __perf_event_remove_from_context,
-				 event);
+	if (!task_function_call(task, __perf_remove_from_context, event))
+		return;
 
 	raw_spin_lock_irq(&ctx->lock);
 	/*
-	 * If the context is active we need to retry the smp call.
+	 * If we failed to find a running task, but find the context active now
+	 * that we've acquired the ctx->lock, retry.
 	 */
-	if (ctx->nr_active && !list_empty(&event->group_entry)) {
+	if (ctx->is_active) {
 		raw_spin_unlock_irq(&ctx->lock);
 		goto retry;
 	}
 
 	/*
-	 * The lock prevents that this context is scheduled in so we
-	 * can remove the event safely, if the call above did not
-	 * succeed.
+	 * Since the task isn't running, its safe to remove the event, us
+	 * holding the ctx->lock ensures the task won't get scheduled in.
 	 */
-	if (!list_empty(&event->group_entry))
-		list_del_event(event, ctx);
+	list_del_event(event, ctx);
 	raw_spin_unlock_irq(&ctx->lock);
 }
 
 /*
  * Cross CPU call to disable a performance event
  */
-static void __perf_event_disable(void *info)
+static int __perf_event_disable(void *info)
 {
 	struct perf_event *event = info;
 	struct perf_event_context *ctx = event->ctx;
@@ -708,9 +1170,12 @@ static void __perf_event_disable(void *info)
 	/*
 	 * If this is a per-task event, need to check whether this
 	 * event's task is the current task on this cpu.
+	 *
+	 * Can trigger due to concurrent perf_event_context_sched_out()
+	 * flipping contexts around.
 	 */
 	if (ctx->task && cpuctx->task_ctx != ctx)
-		return;
+		return -EINVAL;
 
 	raw_spin_lock(&ctx->lock);
 
@@ -720,6 +1185,7 @@ static void __perf_event_disable(void *info)
 	 */
 	if (event->state >= PERF_EVENT_STATE_INACTIVE) {
 		update_context_time(ctx);
+		update_cgrp_time_from_event(event);
 		update_group_times(event);
 		if (event == event->group_leader)
 			group_sched_out(event, cpuctx, ctx);
@@ -729,6 +1195,8 @@ static void __perf_event_disable(void *info)
 	}
 
 	raw_spin_unlock(&ctx->lock);
+
+	return 0;
 }
 
 /*
@@ -753,13 +1221,13 @@ void perf_event_disable(struct perf_event *event)
 		/*
 		 * Disable the event on the cpu that it's on
 		 */
-		smp_call_function_single(event->cpu, __perf_event_disable,
-					 event, 1);
+		cpu_function_call(event->cpu, __perf_event_disable, event);
 		return;
 	}
 
 retry:
-	task_oncpu_function_call(task, __perf_event_disable, event);
+	if (!task_function_call(task, __perf_event_disable, event))
+		return;
 
 	raw_spin_lock_irq(&ctx->lock);
 	/*
@@ -767,6 +1235,11 @@ retry:
 	 */
 	if (event->state == PERF_EVENT_STATE_ACTIVE) {
 		raw_spin_unlock_irq(&ctx->lock);
+		/*
+		 * Reload the task pointer, it might have been changed by
+		 * a concurrent perf_event_context_sched_out().
+		 */
+		task = ctx->task;
 		goto retry;
 	}
 
@@ -778,10 +1251,44 @@ retry:
 		update_group_times(event);
 		event->state = PERF_EVENT_STATE_OFF;
 	}
-
 	raw_spin_unlock_irq(&ctx->lock);
 }
 
+static void perf_set_shadow_time(struct perf_event *event,
+				 struct perf_event_context *ctx,
+				 u64 tstamp)
+{
+	/*
+	 * use the correct time source for the time snapshot
+	 *
+	 * We could get by without this by leveraging the
+	 * fact that to get to this function, the caller
+	 * has most likely already called update_context_time()
+	 * and update_cgrp_time_xx() and thus both timestamp
+	 * are identical (or very close). Given that tstamp is,
+	 * already adjusted for cgroup, we could say that:
+	 *    tstamp - ctx->timestamp
+	 * is equivalent to
+	 *    tstamp - cgrp->timestamp.
+	 *
+	 * Then, in perf_output_read(), the calculation would
+	 * work with no changes because:
+	 * - event is guaranteed scheduled in
+	 * - no scheduled out in between
+	 * - thus the timestamp would be the same
+	 *
+	 * But this is a bit hairy.
+	 *
+	 * So instead, we have an explicit cgroup call to remain
+	 * within the time time source all along. We believe it
+	 * is cleaner and simpler to understand.
+	 */
+	if (is_cgroup_event(event))
+		perf_cgroup_set_shadow_time(event, tstamp);
+	else
+		event->shadow_ctx_time = tstamp - ctx->timestamp;
+}
+
 #define MAX_INTERRUPTS (~0ULL)
 
 static void perf_log_throttle(struct perf_event *event, int enable);
@@ -822,7 +1329,7 @@ event_sched_in(struct perf_event *event,
 
 	event->tstamp_running += tstamp - event->tstamp_stopped;
 
-	event->shadow_ctx_time = tstamp - ctx->timestamp;
+	perf_set_shadow_time(event, ctx, tstamp);
 
 	if (!is_software_event(event))
 		cpuctx->active_oncpu++;
@@ -943,12 +1450,15 @@ static void add_event_to_ctx(struct perf_event *event,
 	event->tstamp_stopped = tstamp;
 }
 
+static void perf_event_context_sched_in(struct perf_event_context *ctx,
+					struct task_struct *tsk);
+
 /*
  * Cross CPU call to install and enable a performance event
  *
  * Must be called with ctx->mutex held
  */
-static void __perf_install_in_context(void *info)
+static int  __perf_install_in_context(void *info)
 {
 	struct perf_event *event = info;
 	struct perf_event_context *ctx = event->ctx;
@@ -957,21 +1467,22 @@ static void __perf_install_in_context(void *info)
 	int err;
 
 	/*
-	 * If this is a task context, we need to check whether it is
-	 * the current task context of this cpu. If not it has been
-	 * scheduled out before the smp call arrived.
-	 * Or possibly this is the right context but it isn't
-	 * on this cpu because it had no events.
+	 * In case we're installing a new context to an already running task,
+	 * could also happen before perf_event_task_sched_in() on architectures
+	 * which do context switches with IRQs enabled.
 	 */
-	if (ctx->task && cpuctx->task_ctx != ctx) {
-		if (cpuctx->task_ctx || ctx->task != current)
-			return;
-		cpuctx->task_ctx = ctx;
-	}
+	if (ctx->task && !cpuctx->task_ctx)
+		perf_event_context_sched_in(ctx, ctx->task);
 
 	raw_spin_lock(&ctx->lock);
 	ctx->is_active = 1;
 	update_context_time(ctx);
+	/*
+	 * update cgrp time only if current cgrp
+	 * matches event->cgrp. Must be done before
+	 * calling add_event_to_ctx()
+	 */
+	update_cgrp_time_from_event(event);
 
 	add_event_to_ctx(event, ctx);
 
@@ -1012,6 +1523,8 @@ static void __perf_install_in_context(void *info)
 
 unlock:
 	raw_spin_unlock(&ctx->lock);
+
+	return 0;
 }
 
 /*
@@ -1023,8 +1536,6 @@ unlock:
  * If the event is attached to a task which is on a CPU we use a smp
  * call to enable it in the task context. The task might have been
  * scheduled away, but we check this in the smp call again.
- *
- * Must be called with ctx->mutex held.
  */
 static void
 perf_install_in_context(struct perf_event_context *ctx,
@@ -1033,6 +1544,8 @@ perf_install_in_context(struct perf_event_context *ctx,
 {
 	struct task_struct *task = ctx->task;
 
+	lockdep_assert_held(&ctx->mutex);
+
 	event->ctx = ctx;
 
 	if (!task) {
@@ -1040,31 +1553,29 @@ perf_install_in_context(struct perf_event_context *ctx,
 		 * Per cpu events are installed via an smp call and
 		 * the install is always successful.
 		 */
-		smp_call_function_single(cpu, __perf_install_in_context,
-					 event, 1);
+		cpu_function_call(cpu, __perf_install_in_context, event);
 		return;
 	}
 
 retry:
-	task_oncpu_function_call(task, __perf_install_in_context,
-				 event);
+	if (!task_function_call(task, __perf_install_in_context, event))
+		return;
 
 	raw_spin_lock_irq(&ctx->lock);
 	/*
-	 * we need to retry the smp call.
+	 * If we failed to find a running task, but find the context active now
+	 * that we've acquired the ctx->lock, retry.
 	 */
-	if (ctx->is_active && list_empty(&event->group_entry)) {
+	if (ctx->is_active) {
 		raw_spin_unlock_irq(&ctx->lock);
 		goto retry;
 	}
 
 	/*
-	 * The lock prevents that this context is scheduled in so we
-	 * can add the event safely, if it the call above did not
-	 * succeed.
+	 * Since the task isn't running, its safe to add the event, us holding
+	 * the ctx->lock ensures the task won't get scheduled in.
 	 */
-	if (list_empty(&event->group_entry))
-		add_event_to_ctx(event, ctx);
+	add_event_to_ctx(event, ctx);
 	raw_spin_unlock_irq(&ctx->lock);
 }
 
@@ -1093,7 +1604,7 @@ static void __perf_event_mark_enabled(struct perf_event *event,
 /*
  * Cross CPU call to enable a performance event
  */
-static void __perf_event_enable(void *info)
+static int __perf_event_enable(void *info)
 {
 	struct perf_event *event = info;
 	struct perf_event_context *ctx = event->ctx;
@@ -1101,26 +1612,27 @@ static void __perf_event_enable(void *info)
 	struct perf_cpu_context *cpuctx = __get_cpu_context(ctx);
 	int err;
 
-	/*
-	 * If this is a per-task event, need to check whether this
-	 * event's task is the current task on this cpu.
-	 */
-	if (ctx->task && cpuctx->task_ctx != ctx) {
-		if (cpuctx->task_ctx || ctx->task != current)
-			return;
-		cpuctx->task_ctx = ctx;
-	}
+	if (WARN_ON_ONCE(!ctx->is_active))
+		return -EINVAL;
 
 	raw_spin_lock(&ctx->lock);
-	ctx->is_active = 1;
 	update_context_time(ctx);
 
 	if (event->state >= PERF_EVENT_STATE_INACTIVE)
 		goto unlock;
+
+	/*
+	 * set current task's cgroup time reference point
+	 */
+	perf_cgroup_set_timestamp(current, ctx);
+
 	__perf_event_mark_enabled(event, ctx);
 
-	if (!event_filter_match(event))
+	if (!event_filter_match(event)) {
+		if (is_cgroup_event(event))
+			perf_cgroup_defer_enabled(event);
 		goto unlock;
+	}
 
 	/*
 	 * If the event is in a group and isn't the group leader,
@@ -1153,6 +1665,8 @@ static void __perf_event_enable(void *info)
 
 unlock:
 	raw_spin_unlock(&ctx->lock);
+
+	return 0;
 }
 
 /*
@@ -1173,8 +1687,7 @@ void perf_event_enable(struct perf_event *event)
 		/*
 		 * Enable the event on the cpu that it's on
 		 */
-		smp_call_function_single(event->cpu, __perf_event_enable,
-					 event, 1);
+		cpu_function_call(event->cpu, __perf_event_enable, event);
 		return;
 	}
 
@@ -1193,8 +1706,15 @@ void perf_event_enable(struct perf_event *event)
 		event->state = PERF_EVENT_STATE_OFF;
 
 retry:
+	if (!ctx->is_active) {
+		__perf_event_mark_enabled(event, ctx);
+		goto out;
+	}
+
 	raw_spin_unlock_irq(&ctx->lock);
-	task_oncpu_function_call(task, __perf_event_enable, event);
+
+	if (!task_function_call(task, __perf_event_enable, event))
+		return;
 
 	raw_spin_lock_irq(&ctx->lock);
 
@@ -1202,15 +1722,14 @@ retry:
 	 * If the context is active and the event is still off,
 	 * we need to retry the cross-call.
 	 */
-	if (ctx->is_active && event->state == PERF_EVENT_STATE_OFF)
+	if (ctx->is_active && event->state == PERF_EVENT_STATE_OFF) {
+		/*
+		 * task could have been flipped by a concurrent
+		 * perf_event_context_sched_out()
+		 */
+		task = ctx->task;
 		goto retry;
-
-	/*
-	 * Since we have the lock this context can't be scheduled
-	 * in, so we can change the state safely.
-	 */
-	if (event->state == PERF_EVENT_STATE_OFF)
-		__perf_event_mark_enabled(event, ctx);
+	}
 
 out:
 	raw_spin_unlock_irq(&ctx->lock);
@@ -1242,6 +1761,7 @@ static void ctx_sched_out(struct perf_event_context *ctx,
 	if (likely(!ctx->nr_events))
 		goto out;
 	update_context_time(ctx);
+	update_cgrp_time_from_cpuctx(cpuctx);
 
 	if (!ctx->nr_active)
 		goto out;
@@ -1354,8 +1874,8 @@ static void perf_event_sync_stat(struct perf_event_context *ctx,
 	}
 }
 
-void perf_event_context_sched_out(struct task_struct *task, int ctxn,
-				  struct task_struct *next)
+static void perf_event_context_sched_out(struct task_struct *task, int ctxn,
+					 struct task_struct *next)
 {
 	struct perf_event_context *ctx = task->perf_event_ctxp[ctxn];
 	struct perf_event_context *next_ctx;
@@ -1431,6 +1951,14 @@ void __perf_event_task_sched_out(struct task_struct *task,
 
 	for_each_task_context_nr(ctxn)
 		perf_event_context_sched_out(task, ctxn, next);
+
+	/*
+	 * if cgroup events exist on this CPU, then we need
+	 * to check if we have to switch out PMU state.
+	 * cgroup event are system-wide mode only
+	 */
+	if (atomic_read(&__get_cpu_var(perf_cgroup_events)))
+		perf_cgroup_sched_out(task);
 }
 
 static void task_ctx_sched_out(struct perf_event_context *ctx,
@@ -1469,6 +1997,10 @@ ctx_pinned_sched_in(struct perf_event_context *ctx,
 		if (!event_filter_match(event))
 			continue;
 
+		/* may need to reset tstamp_enabled */
+		if (is_cgroup_event(event))
+			perf_cgroup_mark_enabled(event, ctx);
+
 		if (group_can_go_on(event, cpuctx, 1))
 			group_sched_in(event, cpuctx, ctx);
 
@@ -1501,6 +2033,10 @@ ctx_flexible_sched_in(struct perf_event_context *ctx,
 		if (!event_filter_match(event))
 			continue;
 
+		/* may need to reset tstamp_enabled */
+		if (is_cgroup_event(event))
+			perf_cgroup_mark_enabled(event, ctx);
+
 		if (group_can_go_on(event, cpuctx, can_add_hw)) {
 			if (group_sched_in(event, cpuctx, ctx))
 				can_add_hw = 0;
@@ -1511,15 +2047,19 @@ ctx_flexible_sched_in(struct perf_event_context *ctx,
 static void
 ctx_sched_in(struct perf_event_context *ctx,
 	     struct perf_cpu_context *cpuctx,
-	     enum event_type_t event_type)
+	     enum event_type_t event_type,
+	     struct task_struct *task)
 {
+	u64 now;
+
 	raw_spin_lock(&ctx->lock);
 	ctx->is_active = 1;
 	if (likely(!ctx->nr_events))
 		goto out;
 
-	ctx->timestamp = perf_clock();
-
+	now = perf_clock();
+	ctx->timestamp = now;
+	perf_cgroup_set_timestamp(task, ctx);
 	/*
 	 * First go through the list and put on any pinned groups
 	 * in order to give them the best chance of going on.
@@ -1536,11 +2076,12 @@ out:
 }
 
 static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx,
-			     enum event_type_t event_type)
+			     enum event_type_t event_type,
+			     struct task_struct *task)
 {
 	struct perf_event_context *ctx = &cpuctx->ctx;
 
-	ctx_sched_in(ctx, cpuctx, event_type);
+	ctx_sched_in(ctx, cpuctx, event_type, task);
 }
 
 static void task_ctx_sched_in(struct perf_event_context *ctx,
@@ -1548,15 +2089,16 @@ static void task_ctx_sched_in(struct perf_event_context *ctx,
 {
 	struct perf_cpu_context *cpuctx;
 
-       	cpuctx = __get_cpu_context(ctx);
+	cpuctx = __get_cpu_context(ctx);
 	if (cpuctx->task_ctx == ctx)
 		return;
 
-	ctx_sched_in(ctx, cpuctx, event_type);
+	ctx_sched_in(ctx, cpuctx, event_type, NULL);
 	cpuctx->task_ctx = ctx;
 }
 
-void perf_event_context_sched_in(struct perf_event_context *ctx)
+static void perf_event_context_sched_in(struct perf_event_context *ctx,
+					struct task_struct *task)
 {
 	struct perf_cpu_context *cpuctx;
 
@@ -1572,9 +2114,9 @@ void perf_event_context_sched_in(struct perf_event_context *ctx)
 	 */
 	cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
 
-	ctx_sched_in(ctx, cpuctx, EVENT_PINNED);
-	cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE);
-	ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE);
+	ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task);
+	cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task);
+	ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task);
 
 	cpuctx->task_ctx = ctx;
 
@@ -1607,8 +2149,15 @@ void __perf_event_task_sched_in(struct task_struct *task)
 		if (likely(!ctx))
 			continue;
 
-		perf_event_context_sched_in(ctx);
+		perf_event_context_sched_in(ctx, task);
 	}
+	/*
+	 * if cgroup events exist on this CPU, then we need
+	 * to check if we have to switch in PMU state.
+	 * cgroup event are system-wide mode only
+	 */
+	if (atomic_read(&__get_cpu_var(perf_cgroup_events)))
+		perf_cgroup_sched_in(task);
 }
 
 static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count)
@@ -1638,7 +2187,7 @@ static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count)
 	 * Reduce accuracy by one bit such that @a and @b converge
 	 * to a similar magnitude.
 	 */
-#define REDUCE_FLS(a, b) 		\
+#define REDUCE_FLS(a, b)		\
 do {					\
 	if (a##_fls > b##_fls) {	\
 		a >>= 1;		\
@@ -1808,7 +2357,7 @@ static void perf_rotate_context(struct perf_cpu_context *cpuctx)
 	if (ctx)
 		rotate_ctx(ctx);
 
-	cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE);
+	cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, current);
 	if (ctx)
 		task_ctx_sched_in(ctx, EVENT_FLEXIBLE);
 
@@ -1887,7 +2436,7 @@ static void perf_event_enable_on_exec(struct perf_event_context *ctx)
 
 	raw_spin_unlock(&ctx->lock);
 
-	perf_event_context_sched_in(ctx);
+	perf_event_context_sched_in(ctx, ctx->task);
 out:
 	local_irq_restore(flags);
 }
@@ -1912,8 +2461,10 @@ static void __perf_event_read(void *info)
 		return;
 
 	raw_spin_lock(&ctx->lock);
-	if (ctx->is_active)
+	if (ctx->is_active) {
 		update_context_time(ctx);
+		update_cgrp_time_from_event(event);
+	}
 	update_event_times(event);
 	if (event->state == PERF_EVENT_STATE_ACTIVE)
 		event->pmu->read(event);
@@ -1944,8 +2495,10 @@ static u64 perf_event_read(struct perf_event *event)
 		 * (e.g., thread is blocked), in that case
 		 * we cannot update context time
 		 */
-		if (ctx->is_active)
+		if (ctx->is_active) {
 			update_context_time(ctx);
+			update_cgrp_time_from_event(event);
+		}
 		update_event_times(event);
 		raw_spin_unlock_irqrestore(&ctx->lock, flags);
 	}
@@ -2224,6 +2777,9 @@ errout:
 
 }
 
+/*
+ * Returns a matching context with refcount and pincount.
+ */
 static struct perf_event_context *
 find_get_context(struct pmu *pmu, struct task_struct *task, int cpu)
 {
@@ -2248,6 +2804,7 @@ find_get_context(struct pmu *pmu, struct task_struct *task, int cpu)
 		cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu);
 		ctx = &cpuctx->ctx;
 		get_ctx(ctx);
+		++ctx->pin_count;
 
 		return ctx;
 	}
@@ -2261,6 +2818,7 @@ retry:
 	ctx = perf_lock_task_context(task, ctxn, &flags);
 	if (ctx) {
 		unclone_ctx(ctx);
+		++ctx->pin_count;
 		raw_spin_unlock_irqrestore(&ctx->lock, flags);
 	}
 
@@ -2282,8 +2840,10 @@ retry:
 			err = -ESRCH;
 		else if (task->perf_event_ctxp[ctxn])
 			err = -EAGAIN;
-		else
+		else {
+			++ctx->pin_count;
 			rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx);
+		}
 		mutex_unlock(&task->perf_event_mutex);
 
 		if (unlikely(err)) {
@@ -2323,7 +2883,7 @@ static void free_event(struct perf_event *event)
 
 	if (!event->parent) {
 		if (event->attach_state & PERF_ATTACH_TASK)
-			jump_label_dec(&perf_task_events);
+			jump_label_dec(&perf_sched_events);
 		if (event->attr.mmap || event->attr.mmap_data)
 			atomic_dec(&nr_mmap_events);
 		if (event->attr.comm)
@@ -2332,6 +2892,10 @@ static void free_event(struct perf_event *event)
 			atomic_dec(&nr_task_events);
 		if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN)
 			put_callchain_buffers();
+		if (is_cgroup_event(event)) {
+			atomic_dec(&per_cpu(perf_cgroup_events, event->cpu));
+			jump_label_dec(&perf_sched_events);
+		}
 	}
 
 	if (event->buffer) {
@@ -2339,6 +2903,9 @@ static void free_event(struct perf_event *event)
 		event->buffer = NULL;
 	}
 
+	if (is_cgroup_event(event))
+		perf_detach_cgroup(event);
+
 	if (event->destroy)
 		event->destroy(event);
 
@@ -4406,26 +4973,14 @@ static int __perf_event_overflow(struct perf_event *event, int nmi,
 	if (unlikely(!is_sampling_event(event)))
 		return 0;
 
-	if (!throttle) {
-		hwc->interrupts++;
-	} else {
-		if (hwc->interrupts != MAX_INTERRUPTS) {
-			hwc->interrupts++;
-			if (HZ * hwc->interrupts >
-					(u64)sysctl_perf_event_sample_rate) {
-				hwc->interrupts = MAX_INTERRUPTS;
-				perf_log_throttle(event, 0);
-				ret = 1;
-			}
-		} else {
-			/*
-			 * Keep re-disabling events even though on the previous
-			 * pass we disabled it - just in case we raced with a
-			 * sched-in and the event got enabled again:
-			 */
+	if (unlikely(hwc->interrupts >= max_samples_per_tick)) {
+		if (throttle) {
+			hwc->interrupts = MAX_INTERRUPTS;
+			perf_log_throttle(event, 0);
 			ret = 1;
 		}
-	}
+	} else
+		hwc->interrupts++;
 
 	if (event->attr.freq) {
 		u64 now = perf_clock();
@@ -5062,6 +5617,10 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
 	u64 period;
 
 	event = container_of(hrtimer, struct perf_event, hw.hrtimer);
+
+	if (event->state != PERF_EVENT_STATE_ACTIVE)
+		return HRTIMER_NORESTART;
+
 	event->pmu->read(event);
 
 	perf_sample_data_init(&data, 0);
@@ -5088,9 +5647,6 @@ static void perf_swevent_start_hrtimer(struct perf_event *event)
 	if (!is_sampling_event(event))
 		return;
 
-	hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-	hwc->hrtimer.function = perf_swevent_hrtimer;
-
 	period = local64_read(&hwc->period_left);
 	if (period) {
 		if (period < 0)
@@ -5117,6 +5673,30 @@ static void perf_swevent_cancel_hrtimer(struct perf_event *event)
 	}
 }
 
+static void perf_swevent_init_hrtimer(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+
+	if (!is_sampling_event(event))
+		return;
+
+	hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hwc->hrtimer.function = perf_swevent_hrtimer;
+
+	/*
+	 * Since hrtimers have a fixed rate, we can do a static freq->period
+	 * mapping and avoid the whole period adjust feedback stuff.
+	 */
+	if (event->attr.freq) {
+		long freq = event->attr.sample_freq;
+
+		event->attr.sample_period = NSEC_PER_SEC / freq;
+		hwc->sample_period = event->attr.sample_period;
+		local64_set(&hwc->period_left, hwc->sample_period);
+		event->attr.freq = 0;
+	}
+}
+
 /*
  * Software event: cpu wall time clock
  */
@@ -5169,6 +5749,8 @@ static int cpu_clock_event_init(struct perf_event *event)
 	if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK)
 		return -ENOENT;
 
+	perf_swevent_init_hrtimer(event);
+
 	return 0;
 }
 
@@ -5224,16 +5806,9 @@ static void task_clock_event_del(struct perf_event *event, int flags)
 
 static void task_clock_event_read(struct perf_event *event)
 {
-	u64 time;
-
-	if (!in_nmi()) {
-		update_context_time(event->ctx);
-		time = event->ctx->time;
-	} else {
-		u64 now = perf_clock();
-		u64 delta = now - event->ctx->timestamp;
-		time = event->ctx->time + delta;
-	}
+	u64 now = perf_clock();
+	u64 delta = now - event->ctx->timestamp;
+	u64 time = event->ctx->time + delta;
 
 	task_clock_event_update(event, time);
 }
@@ -5246,6 +5821,8 @@ static int task_clock_event_init(struct perf_event *event)
 	if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK)
 		return -ENOENT;
 
+	perf_swevent_init_hrtimer(event);
+
 	return 0;
 }
 
@@ -5517,17 +6094,22 @@ struct pmu *perf_init_event(struct perf_event *event)
 {
 	struct pmu *pmu = NULL;
 	int idx;
+	int ret;
 
 	idx = srcu_read_lock(&pmus_srcu);
 
 	rcu_read_lock();
 	pmu = idr_find(&pmu_idr, event->attr.type);
 	rcu_read_unlock();
-	if (pmu)
+	if (pmu) {
+		ret = pmu->event_init(event);
+		if (ret)
+			pmu = ERR_PTR(ret);
 		goto unlock;
+	}
 
 	list_for_each_entry_rcu(pmu, &pmus, entry) {
-		int ret = pmu->event_init(event);
+		ret = pmu->event_init(event);
 		if (!ret)
 			goto unlock;
 
@@ -5653,7 +6235,7 @@ done:
 
 	if (!event->parent) {
 		if (event->attach_state & PERF_ATTACH_TASK)
-			jump_label_inc(&perf_task_events);
+			jump_label_inc(&perf_sched_events);
 		if (event->attr.mmap || event->attr.mmap_data)
 			atomic_inc(&nr_mmap_events);
 		if (event->attr.comm)
@@ -5828,7 +6410,7 @@ SYSCALL_DEFINE5(perf_event_open,
 	int err;
 
 	/* for future expandability... */
-	if (flags & ~(PERF_FLAG_FD_NO_GROUP | PERF_FLAG_FD_OUTPUT))
+	if (flags & ~PERF_FLAG_ALL)
 		return -EINVAL;
 
 	err = perf_copy_attr(attr_uptr, &attr);
@@ -5845,6 +6427,15 @@ SYSCALL_DEFINE5(perf_event_open,
 			return -EINVAL;
 	}
 
+	/*
+	 * In cgroup mode, the pid argument is used to pass the fd
+	 * opened to the cgroup directory in cgroupfs. The cpu argument
+	 * designates the cpu on which to monitor threads from that
+	 * cgroup.
+	 */
+	if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1))
+		return -EINVAL;
+
 	event_fd = get_unused_fd_flags(O_RDWR);
 	if (event_fd < 0)
 		return event_fd;
@@ -5862,7 +6453,7 @@ SYSCALL_DEFINE5(perf_event_open,
 			group_leader = NULL;
 	}
 
-	if (pid != -1) {
+	if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) {
 		task = find_lively_task_by_vpid(pid);
 		if (IS_ERR(task)) {
 			err = PTR_ERR(task);
@@ -5876,6 +6467,19 @@ SYSCALL_DEFINE5(perf_event_open,
 		goto err_task;
 	}
 
+	if (flags & PERF_FLAG_PID_CGROUP) {
+		err = perf_cgroup_connect(pid, event, &attr, group_leader);
+		if (err)
+			goto err_alloc;
+		/*
+		 * one more event:
+		 * - that has cgroup constraint on event->cpu
+		 * - that may need work on context switch
+		 */
+		atomic_inc(&per_cpu(perf_cgroup_events, event->cpu));
+		jump_label_inc(&perf_sched_events);
+	}
+
 	/*
 	 * Special case software events and allow them to be part of
 	 * any hardware group.
@@ -5961,10 +6565,10 @@ SYSCALL_DEFINE5(perf_event_open,
 		struct perf_event_context *gctx = group_leader->ctx;
 
 		mutex_lock(&gctx->mutex);
-		perf_event_remove_from_context(group_leader);
+		perf_remove_from_context(group_leader);
 		list_for_each_entry(sibling, &group_leader->sibling_list,
 				    group_entry) {
-			perf_event_remove_from_context(sibling);
+			perf_remove_from_context(sibling);
 			put_ctx(gctx);
 		}
 		mutex_unlock(&gctx->mutex);
@@ -5987,6 +6591,7 @@ SYSCALL_DEFINE5(perf_event_open,
 
 	perf_install_in_context(ctx, event, cpu);
 	++ctx->generation;
+	perf_unpin_context(ctx);
 	mutex_unlock(&ctx->mutex);
 
 	event->owner = current;
@@ -6012,6 +6617,7 @@ SYSCALL_DEFINE5(perf_event_open,
 	return event_fd;
 
 err_context:
+	perf_unpin_context(ctx);
 	put_ctx(ctx);
 err_alloc:
 	free_event(event);
@@ -6062,6 +6668,7 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
 	mutex_lock(&ctx->mutex);
 	perf_install_in_context(ctx, event, cpu);
 	++ctx->generation;
+	perf_unpin_context(ctx);
 	mutex_unlock(&ctx->mutex);
 
 	return event;
@@ -6115,7 +6722,7 @@ __perf_event_exit_task(struct perf_event *child_event,
 {
 	struct perf_event *parent_event;
 
-	perf_event_remove_from_context(child_event);
+	perf_remove_from_context(child_event);
 
 	parent_event = child_event->parent;
 	/*
@@ -6422,7 +7029,7 @@ inherit_task_group(struct perf_event *event, struct task_struct *parent,
 		return 0;
 	}
 
-       	child_ctx = child->perf_event_ctxp[ctxn];
+	child_ctx = child->perf_event_ctxp[ctxn];
 	if (!child_ctx) {
 		/*
 		 * This is executed from the parent task context, so
@@ -6537,6 +7144,7 @@ int perf_event_init_context(struct task_struct *child, int ctxn)
 	mutex_unlock(&parent_ctx->mutex);
 
 	perf_unpin_context(parent_ctx);
+	put_ctx(parent_ctx);
 
 	return ret;
 }
@@ -6606,9 +7214,9 @@ static void __perf_event_exit_context(void *__info)
 	perf_pmu_rotate_stop(ctx->pmu);
 
 	list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, group_entry)
-		__perf_event_remove_from_context(event);
+		__perf_remove_from_context(event);
 	list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, group_entry)
-		__perf_event_remove_from_context(event);
+		__perf_remove_from_context(event);
 }
 
 static void perf_event_exit_cpu_context(int cpu)
@@ -6732,3 +7340,83 @@ unlock:
 	return ret;
 }
 device_initcall(perf_event_sysfs_init);
+
+#ifdef CONFIG_CGROUP_PERF
+static struct cgroup_subsys_state *perf_cgroup_create(
+	struct cgroup_subsys *ss, struct cgroup *cont)
+{
+	struct perf_cgroup *jc;
+
+	jc = kzalloc(sizeof(*jc), GFP_KERNEL);
+	if (!jc)
+		return ERR_PTR(-ENOMEM);
+
+	jc->info = alloc_percpu(struct perf_cgroup_info);
+	if (!jc->info) {
+		kfree(jc);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	return &jc->css;
+}
+
+static void perf_cgroup_destroy(struct cgroup_subsys *ss,
+				struct cgroup *cont)
+{
+	struct perf_cgroup *jc;
+	jc = container_of(cgroup_subsys_state(cont, perf_subsys_id),
+			  struct perf_cgroup, css);
+	free_percpu(jc->info);
+	kfree(jc);
+}
+
+static int __perf_cgroup_move(void *info)
+{
+	struct task_struct *task = info;
+	perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN);
+	return 0;
+}
+
+static void perf_cgroup_move(struct task_struct *task)
+{
+	task_function_call(task, __perf_cgroup_move, task);
+}
+
+static void perf_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
+		struct cgroup *old_cgrp, struct task_struct *task,
+		bool threadgroup)
+{
+	perf_cgroup_move(task);
+	if (threadgroup) {
+		struct task_struct *c;
+		rcu_read_lock();
+		list_for_each_entry_rcu(c, &task->thread_group, thread_group) {
+			perf_cgroup_move(c);
+		}
+		rcu_read_unlock();
+	}
+}
+
+static void perf_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp,
+		struct cgroup *old_cgrp, 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;
+
+	perf_cgroup_move(task);
+}
+
+struct cgroup_subsys perf_subsys = {
+	.name = "perf_event",
+	.subsys_id = perf_subsys_id,
+	.create = perf_cgroup_create,
+	.destroy = perf_cgroup_destroy,
+	.exit = perf_cgroup_exit,
+	.attach = perf_cgroup_attach,
+};
+#endif /* CONFIG_CGROUP_PERF */
diff --git a/kernel/sched.c b/kernel/sched.c
index 42eab5a8437..57a18e8d28c 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -606,9 +606,6 @@ 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);
@@ -2265,27 +2262,6 @@ void kick_process(struct task_struct *p)
 EXPORT_SYMBOL_GPL(kick_process);
 #endif /* CONFIG_SMP */
 
-/**
- * task_oncpu_function_call - call a function on the cpu on which a task runs
- * @p:		the task to evaluate
- * @func:	the function to be called
- * @info:	the function call argument
- *
- * Calls the function @func when the task is currently running. This might
- * be on the current CPU, which just calls the function directly
- */
-void task_oncpu_function_call(struct task_struct *p,
-			      void (*func) (void *info), void *info)
-{
-	int cpu;
-
-	preempt_disable();
-	cpu = task_cpu(p);
-	if (task_curr(p))
-		smp_call_function_single(cpu, func, info, 1);
-	preempt_enable();
-}
-
 #ifdef CONFIG_SMP
 /*
  * ->cpus_allowed is protected by either TASK_WAKING or rq->lock held.
@@ -2776,9 +2752,12 @@ static inline void
 prepare_task_switch(struct rq *rq, struct task_struct *prev,
 		    struct task_struct *next)
 {
+	sched_info_switch(prev, next);
+	perf_event_task_sched_out(prev, next);
 	fire_sched_out_preempt_notifiers(prev, next);
 	prepare_lock_switch(rq, next);
 	prepare_arch_switch(next);
+	trace_sched_switch(prev, next);
 }
 
 /**
@@ -2911,7 +2890,7 @@ context_switch(struct rq *rq, struct task_struct *prev,
 	struct mm_struct *mm, *oldmm;
 
 	prepare_task_switch(rq, prev, next);
-	trace_sched_switch(prev, next);
+
 	mm = next->mm;
 	oldmm = prev->active_mm;
 	/*
@@ -3989,9 +3968,6 @@ need_resched_nonpreemptible:
 	rq->skip_clock_update = 0;
 
 	if (likely(prev != next)) {
-		sched_info_switch(prev, next);
-		perf_event_task_sched_out(prev, next);
-
 		rq->nr_switches++;
 		rq->curr = next;
 		++*switch_count;
@@ -5572,7 +5548,7 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
 	 * The idle tasks have their own, simple scheduling class:
 	 */
 	idle->sched_class = &idle_sched_class;
-	ftrace_graph_init_task(idle);
+	ftrace_graph_init_idle_task(idle, cpu);
 }
 
 /*
@@ -8885,7 +8861,8 @@ cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
 }
 
 static void
-cpu_cgroup_exit(struct cgroup_subsys *ss, struct task_struct *task)
+cpu_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp,
+		struct cgroup *old_cgrp, struct task_struct *task)
 {
 	/*
 	 * cgroup_exit() is called in the copy_process() failure path.
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 4eed0af5d14..19b9d85e06c 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -948,7 +948,7 @@ static struct ctl_table kern_table[] = {
 		.data		= &sysctl_perf_event_sample_rate,
 		.maxlen		= sizeof(sysctl_perf_event_sample_rate),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
+		.proc_handler	= perf_proc_update_handler,
 	},
 #endif
 #ifdef CONFIG_KMEMCHECK
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index f3dadae8388..888b611897d 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3328,7 +3328,7 @@ static int start_graph_tracing(void)
 	/* The cpu_boot init_task->ret_stack will never be freed */
 	for_each_online_cpu(cpu) {
 		if (!idle_task(cpu)->ret_stack)
-			ftrace_graph_init_task(idle_task(cpu));
+			ftrace_graph_init_idle_task(idle_task(cpu), cpu);
 	}
 
 	do {
@@ -3418,6 +3418,49 @@ void unregister_ftrace_graph(void)
 	mutex_unlock(&ftrace_lock);
 }
 
+static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack);
+
+static void
+graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack)
+{
+	atomic_set(&t->tracing_graph_pause, 0);
+	atomic_set(&t->trace_overrun, 0);
+	t->ftrace_timestamp = 0;
+	/* make curr_ret_stack visable before we add the ret_stack */
+	smp_wmb();
+	t->ret_stack = ret_stack;
+}
+
+/*
+ * Allocate a return stack for the idle task. May be the first
+ * time through, or it may be done by CPU hotplug online.
+ */
+void ftrace_graph_init_idle_task(struct task_struct *t, int cpu)
+{
+	t->curr_ret_stack = -1;
+	/*
+	 * The idle task has no parent, it either has its own
+	 * stack or no stack at all.
+	 */
+	if (t->ret_stack)
+		WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu));
+
+	if (ftrace_graph_active) {
+		struct ftrace_ret_stack *ret_stack;
+
+		ret_stack = per_cpu(idle_ret_stack, cpu);
+		if (!ret_stack) {
+			ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH
+					    * sizeof(struct ftrace_ret_stack),
+					    GFP_KERNEL);
+			if (!ret_stack)
+				return;
+			per_cpu(idle_ret_stack, cpu) = ret_stack;
+		}
+		graph_init_task(t, ret_stack);
+	}
+}
+
 /* Allocate a return stack for newly created task */
 void ftrace_graph_init_task(struct task_struct *t)
 {
@@ -3433,12 +3476,7 @@ void ftrace_graph_init_task(struct task_struct *t)
 				GFP_KERNEL);
 		if (!ret_stack)
 			return;
-		atomic_set(&t->tracing_graph_pause, 0);
-		atomic_set(&t->trace_overrun, 0);
-		t->ftrace_timestamp = 0;
-		/* make curr_ret_stack visable before we add the ret_stack */
-		smp_wmb();
-		t->ret_stack = ret_stack;
+		graph_init_task(t, ret_stack);
 	}
 }
 
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index bd1c35a4fbc..db7b439d23e 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -5,7 +5,6 @@
  */
 #include <linux/ring_buffer.h>
 #include <linux/trace_clock.h>
-#include <linux/ftrace_irq.h>
 #include <linux/spinlock.h>
 #include <linux/debugfs.h>
 #include <linux/uaccess.h>
@@ -1429,6 +1428,17 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size)
 }
 EXPORT_SYMBOL_GPL(ring_buffer_resize);
 
+void ring_buffer_change_overwrite(struct ring_buffer *buffer, int val)
+{
+	mutex_lock(&buffer->mutex);
+	if (val)
+		buffer->flags |= RB_FL_OVERWRITE;
+	else
+		buffer->flags &= ~RB_FL_OVERWRITE;
+	mutex_unlock(&buffer->mutex);
+}
+EXPORT_SYMBOL_GPL(ring_buffer_change_overwrite);
+
 static inline void *
 __rb_data_page_index(struct buffer_data_page *bpage, unsigned index)
 {
@@ -2162,11 +2172,19 @@ rb_reserve_next_event(struct ring_buffer *buffer,
 	if (likely(ts >= cpu_buffer->write_stamp)) {
 		delta = diff;
 		if (unlikely(test_time_stamp(delta))) {
+			int local_clock_stable = 1;
+#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
+			local_clock_stable = sched_clock_stable;
+#endif
 			WARN_ONCE(delta > (1ULL << 59),
-				  KERN_WARNING "Delta way too big! %llu ts=%llu write stamp = %llu\n",
+				  KERN_WARNING "Delta way too big! %llu ts=%llu write stamp = %llu\n%s",
 				  (unsigned long long)delta,
 				  (unsigned long long)ts,
-				  (unsigned long long)cpu_buffer->write_stamp);
+				  (unsigned long long)cpu_buffer->write_stamp,
+				  local_clock_stable ? "" :
+				  "If you just came from a suspend/resume,\n"
+				  "please switch to the trace global clock:\n"
+				  "  echo global > /sys/kernel/debug/tracing/trace_clock\n");
 			add_timestamp = 1;
 		}
 	}
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index dc53ecb8058..9541c27c1cf 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -41,8 +41,6 @@
 #include "trace.h"
 #include "trace_output.h"
 
-#define TRACE_BUFFER_FLAGS	(RB_FL_OVERWRITE)
-
 /*
  * On boot up, the ring buffer is set to the minimum size, so that
  * we do not waste memory on systems that are not using tracing.
@@ -340,7 +338,7 @@ static DECLARE_WAIT_QUEUE_HEAD(trace_wait);
 /* trace_flags holds trace_options default values */
 unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
 	TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME |
-	TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD;
+	TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE;
 
 static int trace_stop_count;
 static DEFINE_SPINLOCK(tracing_start_lock);
@@ -425,6 +423,7 @@ static const char *trace_options[] = {
 	"sleep-time",
 	"graph-time",
 	"record-cmd",
+	"overwrite",
 	NULL
 };
 
@@ -780,6 +779,11 @@ __acquires(kernel_lock)
 		tracing_reset_online_cpus(tr);
 
 		current_trace = type;
+
+		/* If we expanded the buffers, make sure the max is expanded too */
+		if (ring_buffer_expanded && type->use_max_tr)
+			ring_buffer_resize(max_tr.buffer, trace_buf_size);
+
 		/* the test is responsible for initializing and enabling */
 		pr_info("Testing tracer %s: ", type->name);
 		ret = type->selftest(type, tr);
@@ -792,6 +796,10 @@ __acquires(kernel_lock)
 		/* Only reset on passing, to avoid touching corrupted buffers */
 		tracing_reset_online_cpus(tr);
 
+		/* Shrink the max buffer again */
+		if (ring_buffer_expanded && type->use_max_tr)
+			ring_buffer_resize(max_tr.buffer, 1);
+
 		printk(KERN_CONT "PASSED\n");
 	}
 #endif
@@ -1102,7 +1110,6 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
 
 	entry->preempt_count		= pc & 0xff;
 	entry->pid			= (tsk) ? tsk->pid : 0;
-	entry->lock_depth		= (tsk) ? tsk->lock_depth : 0;
 	entry->flags =
 #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
 		(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
@@ -1749,10 +1756,9 @@ static void print_lat_help_header(struct seq_file *m)
 	seq_puts(m, "#                | / _----=> need-resched    \n");
 	seq_puts(m, "#                || / _---=> hardirq/softirq \n");
 	seq_puts(m, "#                ||| / _--=> preempt-depth   \n");
-	seq_puts(m, "#                |||| /_--=> lock-depth       \n");
-	seq_puts(m, "#                |||||/     delay             \n");
-	seq_puts(m, "#  cmd     pid   |||||| time  |   caller      \n");
-	seq_puts(m, "#     \\   /      ||||||   \\   |   /           \n");
+	seq_puts(m, "#                |||| /     delay             \n");
+	seq_puts(m, "#  cmd     pid   ||||| time  |   caller      \n");
+	seq_puts(m, "#     \\   /      |||||  \\    |   /           \n");
 }
 
 static void print_func_help_header(struct seq_file *m)
@@ -2529,6 +2535,9 @@ static void set_tracer_flags(unsigned int mask, int enabled)
 
 	if (mask == TRACE_ITER_RECORD_CMD)
 		trace_event_enable_cmd_record(enabled);
+
+	if (mask == TRACE_ITER_OVERWRITE)
+		ring_buffer_change_overwrite(global_trace.buffer, enabled);
 }
 
 static ssize_t
@@ -2710,6 +2719,10 @@ tracing_ctrl_write(struct file *filp, const char __user *ubuf,
 
 	mutex_lock(&trace_types_lock);
 	if (tracer_enabled ^ val) {
+
+		/* Only need to warn if this is used to change the state */
+		WARN_ONCE(1, "tracing_enabled is deprecated. Use tracing_on");
+
 		if (val) {
 			tracer_enabled = 1;
 			if (current_trace->start)
@@ -4551,9 +4564,11 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
 __init static int tracer_alloc_buffers(void)
 {
 	int ring_buf_size;
+	enum ring_buffer_flags rb_flags;
 	int i;
 	int ret = -ENOMEM;
 
+
 	if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL))
 		goto out;
 
@@ -4566,12 +4581,13 @@ __init static int tracer_alloc_buffers(void)
 	else
 		ring_buf_size = 1;
 
+	rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0;
+
 	cpumask_copy(tracing_buffer_mask, cpu_possible_mask);
 	cpumask_copy(tracing_cpumask, cpu_all_mask);
 
 	/* TODO: make the number of buffers hot pluggable with CPUS */
-	global_trace.buffer = ring_buffer_alloc(ring_buf_size,
-						   TRACE_BUFFER_FLAGS);
+	global_trace.buffer = ring_buffer_alloc(ring_buf_size, rb_flags);
 	if (!global_trace.buffer) {
 		printk(KERN_ERR "tracer: failed to allocate ring buffer!\n");
 		WARN_ON(1);
@@ -4581,7 +4597,7 @@ __init static int tracer_alloc_buffers(void)
 
 
 #ifdef CONFIG_TRACER_MAX_TRACE
-	max_tr.buffer = ring_buffer_alloc(1, TRACE_BUFFER_FLAGS);
+	max_tr.buffer = ring_buffer_alloc(1, rb_flags);
 	if (!max_tr.buffer) {
 		printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n");
 		WARN_ON(1);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 9021f8c0c0c..5e9dfc6286d 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -272,8 +272,8 @@ struct tracer {
 	/* If you handled the flag setting, return 0 */
 	int			(*set_flag)(u32 old_flags, u32 bit, int set);
 	struct tracer		*next;
-	int			print_max;
 	struct tracer_flags	*flags;
+	int			print_max;
 	int			use_max_tr;
 };
 
@@ -606,6 +606,7 @@ enum trace_iterator_flags {
 	TRACE_ITER_SLEEP_TIME		= 0x40000,
 	TRACE_ITER_GRAPH_TIME		= 0x80000,
 	TRACE_ITER_RECORD_CMD		= 0x100000,
+	TRACE_ITER_OVERWRITE		= 0x200000,
 };
 
 /*
@@ -661,8 +662,10 @@ struct ftrace_event_field {
 };
 
 struct event_filter {
-	int			n_preds;
-	struct filter_pred	**preds;
+	int			n_preds;	/* Number assigned */
+	int			a_preds;	/* allocated */
+	struct filter_pred	*preds;
+	struct filter_pred	*root;
 	char			*filter_string;
 };
 
@@ -674,11 +677,23 @@ struct event_subsystem {
 	int			nr_events;
 };
 
+#define FILTER_PRED_INVALID	((unsigned short)-1)
+#define FILTER_PRED_IS_RIGHT	(1 << 15)
+#define FILTER_PRED_FOLD	(1 << 15)
+
+/*
+ * The max preds is the size of unsigned short with
+ * two flags at the MSBs. One bit is used for both the IS_RIGHT
+ * and FOLD flags. The other is reserved.
+ *
+ * 2^14 preds is way more than enough.
+ */
+#define MAX_FILTER_PRED		16384
+
 struct filter_pred;
 struct regex;
 
-typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event,
-				 int val1, int val2);
+typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
 
 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
 
@@ -700,11 +715,23 @@ struct filter_pred {
 	filter_pred_fn_t 	fn;
 	u64 			val;
 	struct regex		regex;
-	char 			*field_name;
+	/*
+	 * Leaf nodes use field_name, ops is used by AND and OR
+	 * nodes. The field_name is always freed when freeing a pred.
+	 * We can overload field_name for ops and have it freed
+	 * as well.
+	 */
+	union {
+		char		*field_name;
+		unsigned short	*ops;
+	};
 	int 			offset;
 	int 			not;
 	int 			op;
-	int 			pop_n;
+	unsigned short		index;
+	unsigned short		parent;
+	unsigned short		left;
+	unsigned short		right;
 };
 
 extern struct list_head ftrace_common_fields;
diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
index 6cf223764be..1516cb3ec54 100644
--- a/kernel/trace/trace_entries.h
+++ b/kernel/trace/trace_entries.h
@@ -109,12 +109,12 @@ FTRACE_ENTRY(funcgraph_exit, ftrace_graph_ret_entry,
  */
 #define FTRACE_CTX_FIELDS					\
 	__field(	unsigned int,	prev_pid	)	\
+	__field(	unsigned int,	next_pid	)	\
+	__field(	unsigned int,	next_cpu	)       \
 	__field(	unsigned char,	prev_prio	)	\
 	__field(	unsigned char,	prev_state	)	\
-	__field(	unsigned int,	next_pid	)	\
 	__field(	unsigned char,	next_prio	)	\
-	__field(	unsigned char,	next_state	)	\
-	__field(	unsigned int,	next_cpu	)
+	__field(	unsigned char,	next_state	)
 
 FTRACE_ENTRY(context_switch, ctx_switch_entry,
 
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 5f499e0438a..e88f74fe1d4 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -116,7 +116,6 @@ static int trace_define_common_fields(void)
 	__common_field(unsigned char, flags);
 	__common_field(unsigned char, preempt_count);
 	__common_field(int, pid);
-	__common_field(int, lock_depth);
 
 	return ret;
 }
@@ -326,6 +325,7 @@ int trace_set_clr_event(const char *system, const char *event, int set)
 {
 	return __ftrace_set_clr_event(NULL, system, event, set);
 }
+EXPORT_SYMBOL_GPL(trace_set_clr_event);
 
 /* 128 should be much more than enough */
 #define EVENT_BUF_SIZE		127
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 36d40104b17..3249b4f77ef 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -123,9 +123,13 @@ struct filter_parse_state {
 	} operand;
 };
 
+struct pred_stack {
+	struct filter_pred	**preds;
+	int			index;
+};
+
 #define DEFINE_COMPARISON_PRED(type)					\
-static int filter_pred_##type(struct filter_pred *pred, void *event,	\
-			      int val1, int val2)			\
+static int filter_pred_##type(struct filter_pred *pred, void *event)	\
 {									\
 	type *addr = (type *)(event + pred->offset);			\
 	type val = (type)pred->val;					\
@@ -152,8 +156,7 @@ static int filter_pred_##type(struct filter_pred *pred, void *event,	\
 }
 
 #define DEFINE_EQUALITY_PRED(size)					\
-static int filter_pred_##size(struct filter_pred *pred, void *event,	\
-			      int val1, int val2)			\
+static int filter_pred_##size(struct filter_pred *pred, void *event)	\
 {									\
 	u##size *addr = (u##size *)(event + pred->offset);		\
 	u##size val = (u##size)pred->val;				\
@@ -178,23 +181,8 @@ DEFINE_EQUALITY_PRED(32);
 DEFINE_EQUALITY_PRED(16);
 DEFINE_EQUALITY_PRED(8);
 
-static int filter_pred_and(struct filter_pred *pred __attribute((unused)),
-			   void *event __attribute((unused)),
-			   int val1, int val2)
-{
-	return val1 && val2;
-}
-
-static int filter_pred_or(struct filter_pred *pred __attribute((unused)),
-			  void *event __attribute((unused)),
-			  int val1, int val2)
-{
-	return val1 || val2;
-}
-
 /* Filter predicate for fixed sized arrays of characters */
-static int filter_pred_string(struct filter_pred *pred, void *event,
-			      int val1, int val2)
+static int filter_pred_string(struct filter_pred *pred, void *event)
 {
 	char *addr = (char *)(event + pred->offset);
 	int cmp, match;
@@ -207,8 +195,7 @@ static int filter_pred_string(struct filter_pred *pred, void *event,
 }
 
 /* Filter predicate for char * pointers */
-static int filter_pred_pchar(struct filter_pred *pred, void *event,
-			     int val1, int val2)
+static int filter_pred_pchar(struct filter_pred *pred, void *event)
 {
 	char **addr = (char **)(event + pred->offset);
 	int cmp, match;
@@ -231,8 +218,7 @@ static int filter_pred_pchar(struct filter_pred *pred, void *event,
  * and add it to the address of the entry, and at last we have
  * the address of the string.
  */
-static int filter_pred_strloc(struct filter_pred *pred, void *event,
-			      int val1, int val2)
+static int filter_pred_strloc(struct filter_pred *pred, void *event)
 {
 	u32 str_item = *(u32 *)(event + pred->offset);
 	int str_loc = str_item & 0xffff;
@@ -247,8 +233,7 @@ static int filter_pred_strloc(struct filter_pred *pred, void *event,
 	return match;
 }
 
-static int filter_pred_none(struct filter_pred *pred, void *event,
-			    int val1, int val2)
+static int filter_pred_none(struct filter_pred *pred, void *event)
 {
 	return 0;
 }
@@ -377,32 +362,147 @@ static void filter_build_regex(struct filter_pred *pred)
 	pred->not ^= not;
 }
 
+enum move_type {
+	MOVE_DOWN,
+	MOVE_UP_FROM_LEFT,
+	MOVE_UP_FROM_RIGHT
+};
+
+static struct filter_pred *
+get_pred_parent(struct filter_pred *pred, struct filter_pred *preds,
+		int index, enum move_type *move)
+{
+	if (pred->parent & FILTER_PRED_IS_RIGHT)
+		*move = MOVE_UP_FROM_RIGHT;
+	else
+		*move = MOVE_UP_FROM_LEFT;
+	pred = &preds[pred->parent & ~FILTER_PRED_IS_RIGHT];
+
+	return pred;
+}
+
+/*
+ * A series of AND or ORs where found together. Instead of
+ * climbing up and down the tree branches, an array of the
+ * ops were made in order of checks. We can just move across
+ * the array and short circuit if needed.
+ */
+static int process_ops(struct filter_pred *preds,
+		       struct filter_pred *op, void *rec)
+{
+	struct filter_pred *pred;
+	int type;
+	int match;
+	int i;
+
+	/*
+	 * Micro-optimization: We set type to true if op
+	 * is an OR and false otherwise (AND). Then we
+	 * just need to test if the match is equal to
+	 * the type, and if it is, we can short circuit the
+	 * rest of the checks:
+	 *
+	 * if ((match && op->op == OP_OR) ||
+	 *     (!match && op->op == OP_AND))
+	 *	  return match;
+	 */
+	type = op->op == OP_OR;
+
+	for (i = 0; i < op->val; i++) {
+		pred = &preds[op->ops[i]];
+		match = pred->fn(pred, rec);
+		if (!!match == type)
+			return match;
+	}
+	return match;
+}
+
 /* return 1 if event matches, 0 otherwise (discard) */
 int filter_match_preds(struct event_filter *filter, void *rec)
 {
-	int match, top = 0, val1 = 0, val2 = 0;
-	int stack[MAX_FILTER_PRED];
+	int match = -1;
+	enum move_type move = MOVE_DOWN;
+	struct filter_pred *preds;
 	struct filter_pred *pred;
-	int i;
+	struct filter_pred *root;
+	int n_preds;
+	int done = 0;
+
+	/* no filter is considered a match */
+	if (!filter)
+		return 1;
+
+	n_preds = filter->n_preds;
+
+	if (!n_preds)
+		return 1;
+
+	/*
+	 * n_preds, root and filter->preds are protect with preemption disabled.
+	 */
+	preds = rcu_dereference_sched(filter->preds);
+	root = rcu_dereference_sched(filter->root);
+	if (!root)
+		return 1;
+
+	pred = root;
 
-	for (i = 0; i < filter->n_preds; i++) {
-		pred = filter->preds[i];
-		if (!pred->pop_n) {
-			match = pred->fn(pred, rec, val1, val2);
-			stack[top++] = match;
+	/* match is currently meaningless */
+	match = -1;
+
+	do {
+		switch (move) {
+		case MOVE_DOWN:
+			/* only AND and OR have children */
+			if (pred->left != FILTER_PRED_INVALID) {
+				/* If ops is set, then it was folded. */
+				if (!pred->ops) {
+					/* keep going to down the left side */
+					pred = &preds[pred->left];
+					continue;
+				}
+				/* We can treat folded ops as a leaf node */
+				match = process_ops(preds, pred, rec);
+			} else
+				match = pred->fn(pred, rec);
+			/* If this pred is the only pred */
+			if (pred == root)
+				break;
+			pred = get_pred_parent(pred, preds,
+					       pred->parent, &move);
+			continue;
+		case MOVE_UP_FROM_LEFT:
+			/*
+			 * Check for short circuits.
+			 *
+			 * Optimization: !!match == (pred->op == OP_OR)
+			 *   is the same as:
+			 * if ((match && pred->op == OP_OR) ||
+			 *     (!match && pred->op == OP_AND))
+			 */
+			if (!!match == (pred->op == OP_OR)) {
+				if (pred == root)
+					break;
+				pred = get_pred_parent(pred, preds,
+						       pred->parent, &move);
+				continue;
+			}
+			/* now go down the right side of the tree. */
+			pred = &preds[pred->right];
+			move = MOVE_DOWN;
+			continue;
+		case MOVE_UP_FROM_RIGHT:
+			/* We finished this equation. */
+			if (pred == root)
+				break;
+			pred = get_pred_parent(pred, preds,
+					       pred->parent, &move);
 			continue;
 		}
-		if (pred->pop_n > top) {
-			WARN_ON_ONCE(1);
-			return 0;
-		}
-		val1 = stack[--top];
-		val2 = stack[--top];
-		match = pred->fn(pred, rec, val1, val2);
-		stack[top++] = match;
-	}
+		done = 1;
+	} while (!done);
 
-	return stack[--top];
+	return match;
 }
 EXPORT_SYMBOL_GPL(filter_match_preds);
 
@@ -414,6 +514,9 @@ static void parse_error(struct filter_parse_state *ps, int err, int pos)
 
 static void remove_filter_string(struct event_filter *filter)
 {
+	if (!filter)
+		return;
+
 	kfree(filter->filter_string);
 	filter->filter_string = NULL;
 }
@@ -473,9 +576,10 @@ static void append_filter_err(struct filter_parse_state *ps,
 
 void print_event_filter(struct ftrace_event_call *call, struct trace_seq *s)
 {
-	struct event_filter *filter = call->filter;
+	struct event_filter *filter;
 
 	mutex_lock(&event_mutex);
+	filter = call->filter;
 	if (filter && filter->filter_string)
 		trace_seq_printf(s, "%s\n", filter->filter_string);
 	else
@@ -486,9 +590,10 @@ void print_event_filter(struct ftrace_event_call *call, struct trace_seq *s)
 void print_subsystem_event_filter(struct event_subsystem *system,
 				  struct trace_seq *s)
 {
-	struct event_filter *filter = system->filter;
+	struct event_filter *filter;
 
 	mutex_lock(&event_mutex);
+	filter = system->filter;
 	if (filter && filter->filter_string)
 		trace_seq_printf(s, "%s\n", filter->filter_string);
 	else
@@ -539,10 +644,58 @@ static void filter_clear_pred(struct filter_pred *pred)
 	pred->regex.len = 0;
 }
 
-static int filter_set_pred(struct filter_pred *dest,
+static int __alloc_pred_stack(struct pred_stack *stack, int n_preds)
+{
+	stack->preds = kzalloc(sizeof(*stack->preds)*(n_preds + 1), GFP_KERNEL);
+	if (!stack->preds)
+		return -ENOMEM;
+	stack->index = n_preds;
+	return 0;
+}
+
+static void __free_pred_stack(struct pred_stack *stack)
+{
+	kfree(stack->preds);
+	stack->index = 0;
+}
+
+static int __push_pred_stack(struct pred_stack *stack,
+			     struct filter_pred *pred)
+{
+	int index = stack->index;
+
+	if (WARN_ON(index == 0))
+		return -ENOSPC;
+
+	stack->preds[--index] = pred;
+	stack->index = index;
+	return 0;
+}
+
+static struct filter_pred *
+__pop_pred_stack(struct pred_stack *stack)
+{
+	struct filter_pred *pred;
+	int index = stack->index;
+
+	pred = stack->preds[index++];
+	if (!pred)
+		return NULL;
+
+	stack->index = index;
+	return pred;
+}
+
+static int filter_set_pred(struct event_filter *filter,
+			   int idx,
+			   struct pred_stack *stack,
 			   struct filter_pred *src,
 			   filter_pred_fn_t fn)
 {
+	struct filter_pred *dest = &filter->preds[idx];
+	struct filter_pred *left;
+	struct filter_pred *right;
+
 	*dest = *src;
 	if (src->field_name) {
 		dest->field_name = kstrdup(src->field_name, GFP_KERNEL);
@@ -550,116 +703,140 @@ static int filter_set_pred(struct filter_pred *dest,
 			return -ENOMEM;
 	}
 	dest->fn = fn;
+	dest->index = idx;
 
-	return 0;
+	if (dest->op == OP_OR || dest->op == OP_AND) {
+		right = __pop_pred_stack(stack);
+		left = __pop_pred_stack(stack);
+		if (!left || !right)
+			return -EINVAL;
+		/*
+		 * If both children can be folded
+		 * and they are the same op as this op or a leaf,
+		 * then this op can be folded.
+		 */
+		if (left->index & FILTER_PRED_FOLD &&
+		    (left->op == dest->op ||
+		     left->left == FILTER_PRED_INVALID) &&
+		    right->index & FILTER_PRED_FOLD &&
+		    (right->op == dest->op ||
+		     right->left == FILTER_PRED_INVALID))
+			dest->index |= FILTER_PRED_FOLD;
+
+		dest->left = left->index & ~FILTER_PRED_FOLD;
+		dest->right = right->index & ~FILTER_PRED_FOLD;
+		left->parent = dest->index & ~FILTER_PRED_FOLD;
+		right->parent = dest->index | FILTER_PRED_IS_RIGHT;
+	} else {
+		/*
+		 * Make dest->left invalid to be used as a quick
+		 * way to know this is a leaf node.
+		 */
+		dest->left = FILTER_PRED_INVALID;
+
+		/* All leafs allow folding the parent ops. */
+		dest->index |= FILTER_PRED_FOLD;
+	}
+
+	return __push_pred_stack(stack, dest);
 }
 
-static void filter_disable_preds(struct ftrace_event_call *call)
+static void __free_preds(struct event_filter *filter)
 {
-	struct event_filter *filter = call->filter;
 	int i;
 
-	call->flags &= ~TRACE_EVENT_FL_FILTERED;
+	if (filter->preds) {
+		for (i = 0; i < filter->a_preds; i++)
+			kfree(filter->preds[i].field_name);
+		kfree(filter->preds);
+		filter->preds = NULL;
+	}
+	filter->a_preds = 0;
 	filter->n_preds = 0;
-
-	for (i = 0; i < MAX_FILTER_PRED; i++)
-		filter->preds[i]->fn = filter_pred_none;
 }
 
-static void __free_preds(struct event_filter *filter)
+static void filter_disable(struct ftrace_event_call *call)
 {
-	int i;
+	call->flags &= ~TRACE_EVENT_FL_FILTERED;
+}
 
+static void __free_filter(struct event_filter *filter)
+{
 	if (!filter)
 		return;
 
-	for (i = 0; i < MAX_FILTER_PRED; i++) {
-		if (filter->preds[i])
-			filter_free_pred(filter->preds[i]);
-	}
-	kfree(filter->preds);
+	__free_preds(filter);
 	kfree(filter->filter_string);
 	kfree(filter);
 }
 
+/*
+ * Called when destroying the ftrace_event_call.
+ * The call is being freed, so we do not need to worry about
+ * the call being currently used. This is for module code removing
+ * the tracepoints from within it.
+ */
 void destroy_preds(struct ftrace_event_call *call)
 {
-	__free_preds(call->filter);
+	__free_filter(call->filter);
 	call->filter = NULL;
-	call->flags &= ~TRACE_EVENT_FL_FILTERED;
 }
 
-static struct event_filter *__alloc_preds(void)
+static struct event_filter *__alloc_filter(void)
 {
 	struct event_filter *filter;
+
+	filter = kzalloc(sizeof(*filter), GFP_KERNEL);
+	return filter;
+}
+
+static int __alloc_preds(struct event_filter *filter, int n_preds)
+{
 	struct filter_pred *pred;
 	int i;
 
-	filter = kzalloc(sizeof(*filter), GFP_KERNEL);
-	if (!filter)
-		return ERR_PTR(-ENOMEM);
+	if (filter->preds)
+		__free_preds(filter);
 
-	filter->n_preds = 0;
+	filter->preds =
+		kzalloc(sizeof(*filter->preds) * n_preds, GFP_KERNEL);
 
-	filter->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred), GFP_KERNEL);
 	if (!filter->preds)
-		goto oom;
+		return -ENOMEM;
 
-	for (i = 0; i < MAX_FILTER_PRED; i++) {
-		pred = kzalloc(sizeof(*pred), GFP_KERNEL);
-		if (!pred)
-			goto oom;
+	filter->a_preds = n_preds;
+	filter->n_preds = 0;
+
+	for (i = 0; i < n_preds; i++) {
+		pred = &filter->preds[i];
 		pred->fn = filter_pred_none;
-		filter->preds[i] = pred;
 	}
 
-	return filter;
-
-oom:
-	__free_preds(filter);
-	return ERR_PTR(-ENOMEM);
-}
-
-static int init_preds(struct ftrace_event_call *call)
-{
-	if (call->filter)
-		return 0;
-
-	call->flags &= ~TRACE_EVENT_FL_FILTERED;
-	call->filter = __alloc_preds();
-	if (IS_ERR(call->filter))
-		return PTR_ERR(call->filter);
-
 	return 0;
 }
 
-static int init_subsystem_preds(struct event_subsystem *system)
+static void filter_free_subsystem_preds(struct event_subsystem *system)
 {
 	struct ftrace_event_call *call;
-	int err;
 
 	list_for_each_entry(call, &ftrace_events, list) {
 		if (strcmp(call->class->system, system->name) != 0)
 			continue;
 
-		err = init_preds(call);
-		if (err)
-			return err;
+		filter_disable(call);
+		remove_filter_string(call->filter);
 	}
-
-	return 0;
 }
 
-static void filter_free_subsystem_preds(struct event_subsystem *system)
+static void filter_free_subsystem_filters(struct event_subsystem *system)
 {
 	struct ftrace_event_call *call;
 
 	list_for_each_entry(call, &ftrace_events, list) {
 		if (strcmp(call->class->system, system->name) != 0)
 			continue;
-
-		filter_disable_preds(call);
-		remove_filter_string(call->filter);
+		__free_filter(call->filter);
+		call->filter = NULL;
 	}
 }
 
@@ -667,18 +844,19 @@ static int filter_add_pred_fn(struct filter_parse_state *ps,
 			      struct ftrace_event_call *call,
 			      struct event_filter *filter,
 			      struct filter_pred *pred,
+			      struct pred_stack *stack,
 			      filter_pred_fn_t fn)
 {
 	int idx, err;
 
-	if (filter->n_preds == MAX_FILTER_PRED) {
+	if (WARN_ON(filter->n_preds == filter->a_preds)) {
 		parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
 		return -ENOSPC;
 	}
 
 	idx = filter->n_preds;
-	filter_clear_pred(filter->preds[idx]);
-	err = filter_set_pred(filter->preds[idx], pred, fn);
+	filter_clear_pred(&filter->preds[idx]);
+	err = filter_set_pred(filter, idx, stack, pred, fn);
 	if (err)
 		return err;
 
@@ -763,6 +941,7 @@ static int filter_add_pred(struct filter_parse_state *ps,
 			   struct ftrace_event_call *call,
 			   struct event_filter *filter,
 			   struct filter_pred *pred,
+			   struct pred_stack *stack,
 			   bool dry_run)
 {
 	struct ftrace_event_field *field;
@@ -770,17 +949,12 @@ static int filter_add_pred(struct filter_parse_state *ps,
 	unsigned long long val;
 	int ret;
 
-	pred->fn = filter_pred_none;
+	fn = pred->fn = filter_pred_none;
 
-	if (pred->op == OP_AND) {
-		pred->pop_n = 2;
-		fn = filter_pred_and;
+	if (pred->op == OP_AND)
 		goto add_pred_fn;
-	} else if (pred->op == OP_OR) {
-		pred->pop_n = 2;
-		fn = filter_pred_or;
+	else if (pred->op == OP_OR)
 		goto add_pred_fn;
-	}
 
 	field = find_event_field(call, pred->field_name);
 	if (!field) {
@@ -829,7 +1003,7 @@ static int filter_add_pred(struct filter_parse_state *ps,
 
 add_pred_fn:
 	if (!dry_run)
-		return filter_add_pred_fn(ps, call, filter, pred, fn);
+		return filter_add_pred_fn(ps, call, filter, pred, stack, fn);
 	return 0;
 }
 
@@ -1187,6 +1361,234 @@ static int check_preds(struct filter_parse_state *ps)
 	return 0;
 }
 
+static int count_preds(struct filter_parse_state *ps)
+{
+	struct postfix_elt *elt;
+	int n_preds = 0;
+
+	list_for_each_entry(elt, &ps->postfix, list) {
+		if (elt->op == OP_NONE)
+			continue;
+		n_preds++;
+	}
+
+	return n_preds;
+}
+
+/*
+ * The tree is walked at filtering of an event. If the tree is not correctly
+ * built, it may cause an infinite loop. Check here that the tree does
+ * indeed terminate.
+ */
+static int check_pred_tree(struct event_filter *filter,
+			   struct filter_pred *root)
+{
+	struct filter_pred *preds;
+	struct filter_pred *pred;
+	enum move_type move = MOVE_DOWN;
+	int count = 0;
+	int done = 0;
+	int max;
+
+	/*
+	 * The max that we can hit a node is three times.
+	 * Once going down, once coming up from left, and
+	 * once coming up from right. This is more than enough
+	 * since leafs are only hit a single time.
+	 */
+	max = 3 * filter->n_preds;
+
+	preds = filter->preds;
+	if  (!preds)
+		return -EINVAL;
+	pred = root;
+
+	do {
+		if (WARN_ON(count++ > max))
+			return -EINVAL;
+
+		switch (move) {
+		case MOVE_DOWN:
+			if (pred->left != FILTER_PRED_INVALID) {
+				pred = &preds[pred->left];
+				continue;
+			}
+			/* A leaf at the root is just a leaf in the tree */
+			if (pred == root)
+				break;
+			pred = get_pred_parent(pred, preds,
+					       pred->parent, &move);
+			continue;
+		case MOVE_UP_FROM_LEFT:
+			pred = &preds[pred->right];
+			move = MOVE_DOWN;
+			continue;
+		case MOVE_UP_FROM_RIGHT:
+			if (pred == root)
+				break;
+			pred = get_pred_parent(pred, preds,
+					       pred->parent, &move);
+			continue;
+		}
+		done = 1;
+	} while (!done);
+
+	/* We are fine. */
+	return 0;
+}
+
+static int count_leafs(struct filter_pred *preds, struct filter_pred *root)
+{
+	struct filter_pred *pred;
+	enum move_type move = MOVE_DOWN;
+	int count = 0;
+	int done = 0;
+
+	pred = root;
+
+	do {
+		switch (move) {
+		case MOVE_DOWN:
+			if (pred->left != FILTER_PRED_INVALID) {
+				pred = &preds[pred->left];
+				continue;
+			}
+			/* A leaf at the root is just a leaf in the tree */
+			if (pred == root)
+				return 1;
+			count++;
+			pred = get_pred_parent(pred, preds,
+					       pred->parent, &move);
+			continue;
+		case MOVE_UP_FROM_LEFT:
+			pred = &preds[pred->right];
+			move = MOVE_DOWN;
+			continue;
+		case MOVE_UP_FROM_RIGHT:
+			if (pred == root)
+				break;
+			pred = get_pred_parent(pred, preds,
+					       pred->parent, &move);
+			continue;
+		}
+		done = 1;
+	} while (!done);
+
+	return count;
+}
+
+static int fold_pred(struct filter_pred *preds, struct filter_pred *root)
+{
+	struct filter_pred *pred;
+	enum move_type move = MOVE_DOWN;
+	int count = 0;
+	int children;
+	int done = 0;
+
+	/* No need to keep the fold flag */
+	root->index &= ~FILTER_PRED_FOLD;
+
+	/* If the root is a leaf then do nothing */
+	if (root->left == FILTER_PRED_INVALID)
+		return 0;
+
+	/* count the children */
+	children = count_leafs(preds, &preds[root->left]);
+	children += count_leafs(preds, &preds[root->right]);
+
+	root->ops = kzalloc(sizeof(*root->ops) * children, GFP_KERNEL);
+	if (!root->ops)
+		return -ENOMEM;
+
+	root->val = children;
+
+	pred = root;
+	do {
+		switch (move) {
+		case MOVE_DOWN:
+			if (pred->left != FILTER_PRED_INVALID) {
+				pred = &preds[pred->left];
+				continue;
+			}
+			if (WARN_ON(count == children))
+				return -EINVAL;
+			pred->index &= ~FILTER_PRED_FOLD;
+			root->ops[count++] = pred->index;
+			pred = get_pred_parent(pred, preds,
+					       pred->parent, &move);
+			continue;
+		case MOVE_UP_FROM_LEFT:
+			pred = &preds[pred->right];
+			move = MOVE_DOWN;
+			continue;
+		case MOVE_UP_FROM_RIGHT:
+			if (pred == root)
+				break;
+			pred = get_pred_parent(pred, preds,
+					       pred->parent, &move);
+			continue;
+		}
+		done = 1;
+	} while (!done);
+
+	return 0;
+}
+
+/*
+ * To optimize the processing of the ops, if we have several "ors" or
+ * "ands" together, we can put them in an array and process them all
+ * together speeding up the filter logic.
+ */
+static int fold_pred_tree(struct event_filter *filter,
+			   struct filter_pred *root)
+{
+	struct filter_pred *preds;
+	struct filter_pred *pred;
+	enum move_type move = MOVE_DOWN;
+	int done = 0;
+	int err;
+
+	preds = filter->preds;
+	if  (!preds)
+		return -EINVAL;
+	pred = root;
+
+	do {
+		switch (move) {
+		case MOVE_DOWN:
+			if (pred->index & FILTER_PRED_FOLD) {
+				err = fold_pred(preds, pred);
+				if (err)
+					return err;
+				/* Folded nodes are like leafs */
+			} else if (pred->left != FILTER_PRED_INVALID) {
+				pred = &preds[pred->left];
+				continue;
+			}
+
+			/* A leaf at the root is just a leaf in the tree */
+			if (pred == root)
+				break;
+			pred = get_pred_parent(pred, preds,
+					       pred->parent, &move);
+			continue;
+		case MOVE_UP_FROM_LEFT:
+			pred = &preds[pred->right];
+			move = MOVE_DOWN;
+			continue;
+		case MOVE_UP_FROM_RIGHT:
+			if (pred == root)
+				break;
+			pred = get_pred_parent(pred, preds,
+					       pred->parent, &move);
+			continue;
+		}
+		done = 1;
+	} while (!done);
+
+	return 0;
+}
+
 static int replace_preds(struct ftrace_event_call *call,
 			 struct event_filter *filter,
 			 struct filter_parse_state *ps,
@@ -1195,14 +1597,32 @@ static int replace_preds(struct ftrace_event_call *call,
 {
 	char *operand1 = NULL, *operand2 = NULL;
 	struct filter_pred *pred;
+	struct filter_pred *root;
 	struct postfix_elt *elt;
+	struct pred_stack stack = { }; /* init to NULL */
 	int err;
 	int n_preds = 0;
 
+	n_preds = count_preds(ps);
+	if (n_preds >= MAX_FILTER_PRED) {
+		parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
+		return -ENOSPC;
+	}
+
 	err = check_preds(ps);
 	if (err)
 		return err;
 
+	if (!dry_run) {
+		err = __alloc_pred_stack(&stack, n_preds);
+		if (err)
+			return err;
+		err = __alloc_preds(filter, n_preds);
+		if (err)
+			goto fail;
+	}
+
+	n_preds = 0;
 	list_for_each_entry(elt, &ps->postfix, list) {
 		if (elt->op == OP_NONE) {
 			if (!operand1)
@@ -1211,14 +1631,16 @@ static int replace_preds(struct ftrace_event_call *call,
 				operand2 = elt->operand;
 			else {
 				parse_error(ps, FILT_ERR_TOO_MANY_OPERANDS, 0);
-				return -EINVAL;
+				err = -EINVAL;
+				goto fail;
 			}
 			continue;
 		}
 
-		if (n_preds++ == MAX_FILTER_PRED) {
+		if (WARN_ON(n_preds++ == MAX_FILTER_PRED)) {
 			parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
-			return -ENOSPC;
+			err = -ENOSPC;
+			goto fail;
 		}
 
 		if (elt->op == OP_AND || elt->op == OP_OR) {
@@ -1228,76 +1650,181 @@ static int replace_preds(struct ftrace_event_call *call,
 
 		if (!operand1 || !operand2) {
 			parse_error(ps, FILT_ERR_MISSING_FIELD, 0);
-			return -EINVAL;
+			err = -EINVAL;
+			goto fail;
 		}
 
 		pred = create_pred(elt->op, operand1, operand2);
 add_pred:
-		if (!pred)
-			return -ENOMEM;
-		err = filter_add_pred(ps, call, filter, pred, dry_run);
+		if (!pred) {
+			err = -ENOMEM;
+			goto fail;
+		}
+		err = filter_add_pred(ps, call, filter, pred, &stack, dry_run);
 		filter_free_pred(pred);
 		if (err)
-			return err;
+			goto fail;
 
 		operand1 = operand2 = NULL;
 	}
 
-	return 0;
+	if (!dry_run) {
+		/* We should have one item left on the stack */
+		pred = __pop_pred_stack(&stack);
+		if (!pred)
+			return -EINVAL;
+		/* This item is where we start from in matching */
+		root = pred;
+		/* Make sure the stack is empty */
+		pred = __pop_pred_stack(&stack);
+		if (WARN_ON(pred)) {
+			err = -EINVAL;
+			filter->root = NULL;
+			goto fail;
+		}
+		err = check_pred_tree(filter, root);
+		if (err)
+			goto fail;
+
+		/* Optimize the tree */
+		err = fold_pred_tree(filter, root);
+		if (err)
+			goto fail;
+
+		/* We don't set root until we know it works */
+		barrier();
+		filter->root = root;
+	}
+
+	err = 0;
+fail:
+	__free_pred_stack(&stack);
+	return err;
 }
 
+struct filter_list {
+	struct list_head	list;
+	struct event_filter	*filter;
+};
+
 static int replace_system_preds(struct event_subsystem *system,
 				struct filter_parse_state *ps,
 				char *filter_string)
 {
 	struct ftrace_event_call *call;
+	struct filter_list *filter_item;
+	struct filter_list *tmp;
+	LIST_HEAD(filter_list);
 	bool fail = true;
 	int err;
 
 	list_for_each_entry(call, &ftrace_events, list) {
-		struct event_filter *filter = call->filter;
 
 		if (strcmp(call->class->system, system->name) != 0)
 			continue;
 
-		/* try to see if the filter can be applied */
-		err = replace_preds(call, filter, ps, filter_string, true);
+		/*
+		 * Try to see if the filter can be applied
+		 *  (filter arg is ignored on dry_run)
+		 */
+		err = replace_preds(call, NULL, ps, filter_string, true);
 		if (err)
+			goto fail;
+	}
+
+	list_for_each_entry(call, &ftrace_events, list) {
+		struct event_filter *filter;
+
+		if (strcmp(call->class->system, system->name) != 0)
 			continue;
 
-		/* really apply the filter */
-		filter_disable_preds(call);
-		err = replace_preds(call, filter, ps, filter_string, false);
+		filter_item = kzalloc(sizeof(*filter_item), GFP_KERNEL);
+		if (!filter_item)
+			goto fail_mem;
+
+		list_add_tail(&filter_item->list, &filter_list);
+
+		filter_item->filter = __alloc_filter();
+		if (!filter_item->filter)
+			goto fail_mem;
+		filter = filter_item->filter;
+
+		/* Can only fail on no memory */
+		err = replace_filter_string(filter, filter_string);
 		if (err)
-			filter_disable_preds(call);
-		else {
+			goto fail_mem;
+
+		err = replace_preds(call, filter, ps, filter_string, false);
+		if (err) {
+			filter_disable(call);
+			parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
+			append_filter_err(ps, filter);
+		} else
 			call->flags |= TRACE_EVENT_FL_FILTERED;
-			replace_filter_string(filter, filter_string);
-		}
+		/*
+		 * Regardless of if this returned an error, we still
+		 * replace the filter for the call.
+		 */
+		filter = call->filter;
+		call->filter = filter_item->filter;
+		filter_item->filter = filter;
+
 		fail = false;
 	}
 
-	if (fail) {
-		parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
-		return -EINVAL;
+	if (fail)
+		goto fail;
+
+	/*
+	 * The calls can still be using the old filters.
+	 * Do a synchronize_sched() to ensure all calls are
+	 * done with them before we free them.
+	 */
+	synchronize_sched();
+	list_for_each_entry_safe(filter_item, tmp, &filter_list, list) {
+		__free_filter(filter_item->filter);
+		list_del(&filter_item->list);
+		kfree(filter_item);
 	}
 	return 0;
+ fail:
+	/* No call succeeded */
+	list_for_each_entry_safe(filter_item, tmp, &filter_list, list) {
+		list_del(&filter_item->list);
+		kfree(filter_item);
+	}
+	parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
+	return -EINVAL;
+ fail_mem:
+	/* If any call succeeded, we still need to sync */
+	if (!fail)
+		synchronize_sched();
+	list_for_each_entry_safe(filter_item, tmp, &filter_list, list) {
+		__free_filter(filter_item->filter);
+		list_del(&filter_item->list);
+		kfree(filter_item);
+	}
+	return -ENOMEM;
 }
 
 int apply_event_filter(struct ftrace_event_call *call, char *filter_string)
 {
-	int err;
 	struct filter_parse_state *ps;
+	struct event_filter *filter;
+	struct event_filter *tmp;
+	int err = 0;
 
 	mutex_lock(&event_mutex);
 
-	err = init_preds(call);
-	if (err)
-		goto out_unlock;
-
 	if (!strcmp(strstrip(filter_string), "0")) {
-		filter_disable_preds(call);
-		remove_filter_string(call->filter);
+		filter_disable(call);
+		filter = call->filter;
+		if (!filter)
+			goto out_unlock;
+		call->filter = NULL;
+		/* Make sure the filter is not being used */
+		synchronize_sched();
+		__free_filter(filter);
 		goto out_unlock;
 	}
 
@@ -1306,22 +1833,41 @@ int apply_event_filter(struct ftrace_event_call *call, char *filter_string)
 	if (!ps)
 		goto out_unlock;
 
-	filter_disable_preds(call);
-	replace_filter_string(call->filter, filter_string);
+	filter = __alloc_filter();
+	if (!filter) {
+		kfree(ps);
+		goto out_unlock;
+	}
+
+	replace_filter_string(filter, filter_string);
 
 	parse_init(ps, filter_ops, filter_string);
 	err = filter_parse(ps);
 	if (err) {
-		append_filter_err(ps, call->filter);
+		append_filter_err(ps, filter);
 		goto out;
 	}
 
-	err = replace_preds(call, call->filter, ps, filter_string, false);
-	if (err)
-		append_filter_err(ps, call->filter);
-	else
+	err = replace_preds(call, filter, ps, filter_string, false);
+	if (err) {
+		filter_disable(call);
+		append_filter_err(ps, filter);
+	} else
 		call->flags |= TRACE_EVENT_FL_FILTERED;
 out:
+	/*
+	 * Always swap the call filter with the new filter
+	 * even if there was an error. If there was an error
+	 * in the filter, we disable the filter and show the error
+	 * string
+	 */
+	tmp = call->filter;
+	call->filter = filter;
+	if (tmp) {
+		/* Make sure the call is done with the filter */
+		synchronize_sched();
+		__free_filter(tmp);
+	}
 	filter_opstack_clear(ps);
 	postfix_clear(ps);
 	kfree(ps);
@@ -1334,18 +1880,21 @@ out_unlock:
 int apply_subsystem_event_filter(struct event_subsystem *system,
 				 char *filter_string)
 {
-	int err;
 	struct filter_parse_state *ps;
+	struct event_filter *filter;
+	int err = 0;
 
 	mutex_lock(&event_mutex);
 
-	err = init_subsystem_preds(system);
-	if (err)
-		goto out_unlock;
-
 	if (!strcmp(strstrip(filter_string), "0")) {
 		filter_free_subsystem_preds(system);
 		remove_filter_string(system->filter);
+		filter = system->filter;
+		system->filter = NULL;
+		/* Ensure all filters are no longer used */
+		synchronize_sched();
+		filter_free_subsystem_filters(system);
+		__free_filter(filter);
 		goto out_unlock;
 	}
 
@@ -1354,7 +1903,17 @@ int apply_subsystem_event_filter(struct event_subsystem *system,
 	if (!ps)
 		goto out_unlock;
 
-	replace_filter_string(system->filter, filter_string);
+	filter = __alloc_filter();
+	if (!filter)
+		goto out;
+
+	replace_filter_string(filter, filter_string);
+	/*
+	 * No event actually uses the system filter
+	 * we can free it without synchronize_sched().
+	 */
+	__free_filter(system->filter);
+	system->filter = filter;
 
 	parse_init(ps, filter_ops, filter_string);
 	err = filter_parse(ps);
@@ -1384,7 +1943,7 @@ void ftrace_profile_free_filter(struct perf_event *event)
 	struct event_filter *filter = event->filter;
 
 	event->filter = NULL;
-	__free_preds(filter);
+	__free_filter(filter);
 }
 
 int ftrace_profile_set_filter(struct perf_event *event, int event_id,
@@ -1410,8 +1969,8 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
 	if (event->filter)
 		goto out_unlock;
 
-	filter = __alloc_preds();
-	if (IS_ERR(filter)) {
+	filter = __alloc_filter();
+	if (!filter) {
 		err = PTR_ERR(filter);
 		goto out_unlock;
 	}
@@ -1419,7 +1978,7 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
 	err = -ENOMEM;
 	ps = kzalloc(sizeof(*ps), GFP_KERNEL);
 	if (!ps)
-		goto free_preds;
+		goto free_filter;
 
 	parse_init(ps, filter_ops, filter_str);
 	err = filter_parse(ps);
@@ -1435,9 +1994,9 @@ free_ps:
 	postfix_clear(ps);
 	kfree(ps);
 
-free_preds:
+free_filter:
 	if (err)
-		__free_preds(filter);
+		__free_filter(filter);
 
 out_unlock:
 	mutex_unlock(&event_mutex);
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 2dec9bcde8b..8435b43b178 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -353,6 +353,43 @@ static __kprobes void free_deref_fetch_param(struct deref_fetch_param *data)
 	kfree(data);
 }
 
+/* Bitfield fetch function */
+struct bitfield_fetch_param {
+	struct fetch_param orig;
+	unsigned char hi_shift;
+	unsigned char low_shift;
+};
+
+#define DEFINE_FETCH_bitfield(type)					\
+static __kprobes void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs,\
+					    void *data, void *dest)	\
+{									\
+	struct bitfield_fetch_param *bprm = data;			\
+	type buf = 0;							\
+	call_fetch(&bprm->orig, regs, &buf);				\
+	if (buf) {							\
+		buf <<= bprm->hi_shift;					\
+		buf >>= bprm->low_shift;				\
+	}								\
+	*(type *)dest = buf;						\
+}
+DEFINE_BASIC_FETCH_FUNCS(bitfield)
+#define fetch_bitfield_string NULL
+#define fetch_bitfield_string_size NULL
+
+static __kprobes void
+free_bitfield_fetch_param(struct bitfield_fetch_param *data)
+{
+	/*
+	 * Don't check the bitfield itself, because this must be the
+	 * last fetch function.
+	 */
+	if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
+		free_deref_fetch_param(data->orig.data);
+	else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
+		free_symbol_cache(data->orig.data);
+	kfree(data);
+}
 /* Default (unsigned long) fetch type */
 #define __DEFAULT_FETCH_TYPE(t) u##t
 #define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
@@ -367,6 +404,7 @@ enum {
 	FETCH_MTD_memory,
 	FETCH_MTD_symbol,
 	FETCH_MTD_deref,
+	FETCH_MTD_bitfield,
 	FETCH_MTD_END,
 };
 
@@ -387,6 +425,7 @@ ASSIGN_FETCH_FUNC(retval, ftype),			\
 ASSIGN_FETCH_FUNC(memory, ftype),			\
 ASSIGN_FETCH_FUNC(symbol, ftype),			\
 ASSIGN_FETCH_FUNC(deref, ftype),			\
+ASSIGN_FETCH_FUNC(bitfield, ftype),			\
 	  }						\
 	}
 
@@ -430,9 +469,33 @@ static const struct fetch_type *find_fetch_type(const char *type)
 	if (!type)
 		type = DEFAULT_FETCH_TYPE_STR;
 
+	/* Special case: bitfield */
+	if (*type == 'b') {
+		unsigned long bs;
+		type = strchr(type, '/');
+		if (!type)
+			goto fail;
+		type++;
+		if (strict_strtoul(type, 0, &bs))
+			goto fail;
+		switch (bs) {
+		case 8:
+			return find_fetch_type("u8");
+		case 16:
+			return find_fetch_type("u16");
+		case 32:
+			return find_fetch_type("u32");
+		case 64:
+			return find_fetch_type("u64");
+		default:
+			goto fail;
+		}
+	}
+
 	for (i = 0; i < ARRAY_SIZE(fetch_type_table); i++)
 		if (strcmp(type, fetch_type_table[i].name) == 0)
 			return &fetch_type_table[i];
+fail:
 	return NULL;
 }
 
@@ -586,7 +649,9 @@ error:
 
 static void free_probe_arg(struct probe_arg *arg)
 {
-	if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
+	if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn))
+		free_bitfield_fetch_param(arg->fetch.data);
+	else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
 		free_deref_fetch_param(arg->fetch.data);
 	else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn))
 		free_symbol_cache(arg->fetch.data);
@@ -767,16 +832,15 @@ static int __parse_probe_arg(char *arg, const struct fetch_type *t,
 		}
 		break;
 	case '+':	/* deref memory */
+		arg++;	/* Skip '+', because strict_strtol() rejects it. */
 	case '-':
 		tmp = strchr(arg, '(');
 		if (!tmp)
 			break;
 		*tmp = '\0';
-		ret = strict_strtol(arg + 1, 0, &offset);
+		ret = strict_strtol(arg, 0, &offset);
 		if (ret)
 			break;
-		if (arg[0] == '-')
-			offset = -offset;
 		arg = tmp + 1;
 		tmp = strrchr(arg, ')');
 		if (tmp) {
@@ -807,6 +871,41 @@ static int __parse_probe_arg(char *arg, const struct fetch_type *t,
 	return ret;
 }
 
+#define BYTES_TO_BITS(nb)	((BITS_PER_LONG * (nb)) / sizeof(long))
+
+/* Bitfield type needs to be parsed into a fetch function */
+static int __parse_bitfield_probe_arg(const char *bf,
+				      const struct fetch_type *t,
+				      struct fetch_param *f)
+{
+	struct bitfield_fetch_param *bprm;
+	unsigned long bw, bo;
+	char *tail;
+
+	if (*bf != 'b')
+		return 0;
+
+	bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
+	if (!bprm)
+		return -ENOMEM;
+	bprm->orig = *f;
+	f->fn = t->fetch[FETCH_MTD_bitfield];
+	f->data = (void *)bprm;
+
+	bw = simple_strtoul(bf + 1, &tail, 0);	/* Use simple one */
+	if (bw == 0 || *tail != '@')
+		return -EINVAL;
+
+	bf = tail + 1;
+	bo = simple_strtoul(bf, &tail, 0);
+	if (tail == bf || *tail != '/')
+		return -EINVAL;
+
+	bprm->hi_shift = BYTES_TO_BITS(t->size) - (bw + bo);
+	bprm->low_shift = bprm->hi_shift + bo;
+	return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0;
+}
+
 /* String length checking wrapper */
 static int parse_probe_arg(char *arg, struct trace_probe *tp,
 			   struct probe_arg *parg, int is_return)
@@ -836,6 +935,8 @@ static int parse_probe_arg(char *arg, struct trace_probe *tp,
 	parg->offset = tp->size;
 	tp->size += parg->type->size;
 	ret = __parse_probe_arg(arg, parg->type, &parg->fetch, is_return);
+	if (ret >= 0 && t != NULL)
+		ret = __parse_bitfield_probe_arg(t, parg->type, &parg->fetch);
 	if (ret >= 0) {
 		parg->fetch_size.fn = get_fetch_size_function(parg->type,
 							      parg->fetch.fn);
@@ -1130,7 +1231,7 @@ static int command_trace_probe(const char *buf)
 	return ret;
 }
 
-#define WRITE_BUFSIZE 128
+#define WRITE_BUFSIZE 4096
 
 static ssize_t probes_write(struct file *file, const char __user *buffer,
 			    size_t count, loff_t *ppos)
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 02272baa220..456be9063c2 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -529,24 +529,34 @@ seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
  * @entry: The trace entry field from the ring buffer
  *
  * Prints the generic fields of irqs off, in hard or softirq, preempt
- * count and lock depth.
+ * count.
  */
 int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 {
-	int hardirq, softirq;
+	char hardsoft_irq;
+	char need_resched;
+	char irqs_off;
+	int hardirq;
+	int softirq;
 	int ret;
 
 	hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
 	softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
 
+	irqs_off =
+		(entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
+		(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
+		'.';
+	need_resched =
+		(entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.';
+	hardsoft_irq =
+		(hardirq && softirq) ? 'H' :
+		hardirq ? 'h' :
+		softirq ? 's' :
+		'.';
+
 	if (!trace_seq_printf(s, "%c%c%c",
-			      (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
-				(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ?
-				  'X' : '.',
-			      (entry->flags & TRACE_FLAG_NEED_RESCHED) ?
-				'N' : '.',
-			      (hardirq && softirq) ? 'H' :
-				hardirq ? 'h' : softirq ? 's' : '.'))
+			      irqs_off, need_resched, hardsoft_irq))
 		return 0;
 
 	if (entry->preempt_count)
@@ -554,13 +564,7 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 	else
 		ret = trace_seq_putc(s, '.');
 
-	if (!ret)
-		return 0;
-
-	if (entry->lock_depth < 0)
-		return trace_seq_putc(s, '.');
-
-	return trace_seq_printf(s, "%d", entry->lock_depth);
+	return ret;
 }
 
 static int
diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c
index 8f758d070c4..7e62c0a1845 100644
--- a/kernel/trace/trace_sched_switch.c
+++ b/kernel/trace/trace_sched_switch.c
@@ -247,51 +247,3 @@ void tracing_sched_switch_assign_trace(struct trace_array *tr)
 	ctx_trace = tr;
 }
 
-static void stop_sched_trace(struct trace_array *tr)
-{
-	tracing_stop_sched_switch_record();
-}
-
-static int sched_switch_trace_init(struct trace_array *tr)
-{
-	ctx_trace = tr;
-	tracing_reset_online_cpus(tr);
-	tracing_start_sched_switch_record();
-	return 0;
-}
-
-static void sched_switch_trace_reset(struct trace_array *tr)
-{
-	if (sched_ref)
-		stop_sched_trace(tr);
-}
-
-static void sched_switch_trace_start(struct trace_array *tr)
-{
-	sched_stopped = 0;
-}
-
-static void sched_switch_trace_stop(struct trace_array *tr)
-{
-	sched_stopped = 1;
-}
-
-static struct tracer sched_switch_trace __read_mostly =
-{
-	.name		= "sched_switch",
-	.init		= sched_switch_trace_init,
-	.reset		= sched_switch_trace_reset,
-	.start		= sched_switch_trace_start,
-	.stop		= sched_switch_trace_stop,
-	.wait_pipe	= poll_wait_pipe,
-#ifdef CONFIG_FTRACE_SELFTEST
-	.selftest    = trace_selftest_startup_sched_switch,
-#endif
-};
-
-__init static int init_sched_switch_trace(void)
-{
-	return register_tracer(&sched_switch_trace);
-}
-device_initcall(init_sched_switch_trace);
-
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 5c9fe08d209..ee7b5a0bb9f 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -60,6 +60,19 @@ extern struct syscall_metadata *__stop_syscalls_metadata[];
 
 static struct syscall_metadata **syscalls_metadata;
 
+#ifndef ARCH_HAS_SYSCALL_MATCH_SYM_NAME
+static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
+{
+	/*
+	 * Only compare after the "sys" prefix. Archs that use
+	 * syscall wrappers may have syscalls symbols aliases prefixed
+	 * with "SyS" instead of "sys", leading to an unwanted
+	 * mismatch.
+	 */
+	return !strcmp(sym + 3, name + 3);
+}
+#endif
+
 static __init struct syscall_metadata *
 find_syscall_meta(unsigned long syscall)
 {
@@ -72,14 +85,11 @@ find_syscall_meta(unsigned long syscall)
 	stop = __stop_syscalls_metadata;
 	kallsyms_lookup(syscall, NULL, NULL, NULL, str);
 
+	if (arch_syscall_match_sym_name(str, "sys_ni_syscall"))
+		return NULL;
+
 	for ( ; start < stop; start++) {
-		/*
-		 * Only compare after the "sys" prefix. Archs that use
-		 * syscall wrappers may have syscalls symbols aliases prefixed
-		 * with "SyS" instead of "sys", leading to an unwanted
-		 * mismatch.
-		 */
-		if ((*start)->name && !strcmp((*start)->name + 3, str + 3))
+		if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name))
 			return *start;
 	}
 	return NULL;
@@ -359,7 +369,7 @@ int reg_event_syscall_enter(struct ftrace_event_call *call)
 	int num;
 
 	num = ((struct syscall_metadata *)call->data)->syscall_nr;
-	if (num < 0 || num >= NR_syscalls)
+	if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
 		return -ENOSYS;
 	mutex_lock(&syscall_trace_lock);
 	if (!sys_refcount_enter)
@@ -377,7 +387,7 @@ void unreg_event_syscall_enter(struct ftrace_event_call *call)
 	int num;
 
 	num = ((struct syscall_metadata *)call->data)->syscall_nr;
-	if (num < 0 || num >= NR_syscalls)
+	if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
 		return;
 	mutex_lock(&syscall_trace_lock);
 	sys_refcount_enter--;
@@ -393,7 +403,7 @@ int reg_event_syscall_exit(struct ftrace_event_call *call)
 	int num;
 
 	num = ((struct syscall_metadata *)call->data)->syscall_nr;
-	if (num < 0 || num >= NR_syscalls)
+	if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
 		return -ENOSYS;
 	mutex_lock(&syscall_trace_lock);
 	if (!sys_refcount_exit)
@@ -411,7 +421,7 @@ void unreg_event_syscall_exit(struct ftrace_event_call *call)
 	int num;
 
 	num = ((struct syscall_metadata *)call->data)->syscall_nr;
-	if (num < 0 || num >= NR_syscalls)
+	if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
 		return;
 	mutex_lock(&syscall_trace_lock);
 	sys_refcount_exit--;
@@ -424,6 +434,14 @@ void unreg_event_syscall_exit(struct ftrace_event_call *call)
 int init_syscall_trace(struct ftrace_event_call *call)
 {
 	int id;
+	int num;
+
+	num = ((struct syscall_metadata *)call->data)->syscall_nr;
+	if (num < 0 || num >= NR_syscalls) {
+		pr_debug("syscall %s metadata not mapped, disabling ftrace event\n",
+				((struct syscall_metadata *)call->data)->name);
+		return -ENOSYS;
+	}
 
 	if (set_syscall_print_fmt(call) < 0)
 		return -ENOMEM;
@@ -438,7 +456,7 @@ int init_syscall_trace(struct ftrace_event_call *call)
 	return id;
 }
 
-unsigned long __init arch_syscall_addr(int nr)
+unsigned long __init __weak arch_syscall_addr(int nr)
 {
 	return (unsigned long)sys_call_table[nr];
 }