1 files changed, 392 insertions, 217 deletions

diff --git a/kernel/events/core.c b/kernel/events/core.c
index f86599e8c12..8c875ef6e12 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -145,6 +145,7 @@ static DEFINE_PER_CPU(atomic_t, perf_branch_stack_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;
+static atomic_t nr_freq_events __read_mostly;
 
 static LIST_HEAD(pmus);
 static DEFINE_MUTEX(pmus_lock);
@@ -174,8 +175,8 @@ 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);
 static int perf_sample_period_ns __read_mostly	= DEFAULT_SAMPLE_PERIOD_NS;
 
-static atomic_t perf_sample_allowed_ns __read_mostly =
-	ATOMIC_INIT( DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100);
+static int perf_sample_allowed_ns __read_mostly =
+	DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100;
 
 void update_perf_cpu_limits(void)
 {
@@ -183,7 +184,7 @@ void update_perf_cpu_limits(void)
 
 	tmp *= sysctl_perf_cpu_time_max_percent;
 	do_div(tmp, 100);
-	atomic_set(&perf_sample_allowed_ns, tmp);
+	ACCESS_ONCE(perf_sample_allowed_ns) = tmp;
 }
 
 static int perf_rotate_context(struct perf_cpu_context *cpuctx);
@@ -192,7 +193,7 @@ 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);
+	int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
 
 	if (ret || !write)
 		return ret;
@@ -227,14 +228,15 @@ int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write,
  * we detect that events are taking too long.
  */
 #define NR_ACCUMULATED_SAMPLES 128
-DEFINE_PER_CPU(u64, running_sample_length);
+static DEFINE_PER_CPU(u64, running_sample_length);
 
 void perf_sample_event_took(u64 sample_len_ns)
 {
 	u64 avg_local_sample_len;
 	u64 local_samples_len;
+	u64 allowed_ns = ACCESS_ONCE(perf_sample_allowed_ns);
 
-	if (atomic_read(&perf_sample_allowed_ns) == 0)
+	if (allowed_ns == 0)
 		return;
 
 	/* decay the counter by 1 average sample */
@@ -250,7 +252,7 @@ void perf_sample_event_took(u64 sample_len_ns)
 	 */
 	avg_local_sample_len = local_samples_len/NR_ACCUMULATED_SAMPLES;
 
-	if (avg_local_sample_len <= atomic_read(&perf_sample_allowed_ns))
+	if (avg_local_sample_len <= allowed_ns)
 		return;
 
 	if (max_samples_per_tick <= 1)
@@ -261,10 +263,9 @@ void perf_sample_event_took(u64 sample_len_ns)
 	perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate;
 
 	printk_ratelimited(KERN_WARNING
-			"perf samples too long (%lld > %d), lowering "
+			"perf samples too long (%lld > %lld), lowering "
 			"kernel.perf_event_max_sample_rate to %d\n",
-			avg_local_sample_len,
-			atomic_read(&perf_sample_allowed_ns),
+			avg_local_sample_len, allowed_ns,
 			sysctl_perf_event_sample_rate);
 
 	update_perf_cpu_limits();
@@ -340,8 +341,8 @@ struct perf_cgroup {
 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);
+	return container_of(task_css(task, perf_subsys_id),
+			    struct perf_cgroup, css);
 }
 
 static inline bool
@@ -591,7 +592,9 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
 	if (!f.file)
 		return -EBADF;
 
-	css = cgroup_css_from_dir(f.file, perf_subsys_id);
+	rcu_read_lock();
+
+	css = css_from_dir(f.file->f_dentry, &perf_subsys);
 	if (IS_ERR(css)) {
 		ret = PTR_ERR(css);
 		goto out;
@@ -617,6 +620,7 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
 		ret = -EINVAL;
 	}
 out:
+	rcu_read_unlock();
 	fdput(f);
 	return ret;
 }
@@ -869,12 +873,8 @@ static void perf_pmu_rotate_start(struct pmu *pmu)
 
 	WARN_ON(!irqs_disabled());
 
-	if (list_empty(&cpuctx->rotation_list)) {
-		int was_empty = list_empty(head);
+	if (list_empty(&cpuctx->rotation_list))
 		list_add(&cpuctx->rotation_list, head);
-		if (was_empty)
-			tick_nohz_full_kick();
-	}
 }
 
 static void get_ctx(struct perf_event_context *ctx)
@@ -899,6 +899,7 @@ static void unclone_ctx(struct perf_event_context *ctx)
 		put_ctx(ctx->parent_ctx);
 		ctx->parent_ctx = NULL;
 	}
+	ctx->generation++;
 }
 
 static u32 perf_event_pid(struct perf_event *event, struct task_struct *p)
@@ -1136,6 +1137,8 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx)
 	ctx->nr_events++;
 	if (event->attr.inherit_stat)
 		ctx->nr_stat++;
+
+	ctx->generation++;
 }
 
 /*
@@ -1201,6 +1204,9 @@ static void perf_event__header_size(struct perf_event *event)
 	if (sample_type & PERF_SAMPLE_DATA_SRC)
 		size += sizeof(data->data_src.val);
 
+	if (sample_type & PERF_SAMPLE_TRANSACTION)
+		size += sizeof(data->txn);
+
 	event->header_size = size;
 }
 
@@ -1216,6 +1222,9 @@ static void perf_event__id_header_size(struct perf_event *event)
 	if (sample_type & PERF_SAMPLE_TIME)
 		size += sizeof(data->time);
 
+	if (sample_type & PERF_SAMPLE_IDENTIFIER)
+		size += sizeof(data->id);
+
 	if (sample_type & PERF_SAMPLE_ID)
 		size += sizeof(data->id);
 
@@ -1307,6 +1316,8 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx)
 	 */
 	if (event->state > PERF_EVENT_STATE_OFF)
 		event->state = PERF_EVENT_STATE_OFF;
+
+	ctx->generation++;
 }
 
 static void perf_group_detach(struct perf_event *event)
@@ -2143,22 +2154,38 @@ static void ctx_sched_out(struct perf_event_context *ctx,
 }
 
 /*
- * Test whether two contexts are equivalent, i.e. whether they
- * have both been cloned from the same version of the same context
- * and they both have the same number of enabled events.
- * If the number of enabled events is the same, then the set
- * of enabled events should be the same, because these are both
- * inherited contexts, therefore we can't access individual events
- * in them directly with an fd; we can only enable/disable all
- * events via prctl, or enable/disable all events in a family
- * via ioctl, which will have the same effect on both contexts.
+ * Test whether two contexts are equivalent, i.e. whether they have both been
+ * cloned from the same version of the same context.
+ *
+ * Equivalence is measured using a generation number in the context that is
+ * incremented on each modification to it; see unclone_ctx(), list_add_event()
+ * and list_del_event().
  */
 static int context_equiv(struct perf_event_context *ctx1,
 			 struct perf_event_context *ctx2)
 {
-	return ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx
-		&& ctx1->parent_gen == ctx2->parent_gen
-		&& !ctx1->pin_count && !ctx2->pin_count;
+	/* Pinning disables the swap optimization */
+	if (ctx1->pin_count || ctx2->pin_count)
+		return 0;
+
+	/* If ctx1 is the parent of ctx2 */
+	if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen)
+		return 1;
+
+	/* If ctx2 is the parent of ctx1 */
+	if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation)
+		return 1;
+
+	/*
+	 * If ctx1 and ctx2 have the same parent; we flatten the parent
+	 * hierarchy, see perf_event_init_context().
+	 */
+	if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx &&
+			ctx1->parent_gen == ctx2->parent_gen)
+		return 1;
+
+	/* Unmatched */
+	return 0;
 }
 
 static void __perf_event_sync_stat(struct perf_event *event,
@@ -2241,7 +2268,7 @@ static void perf_event_context_sched_out(struct task_struct *task, int ctxn,
 {
 	struct perf_event_context *ctx = task->perf_event_ctxp[ctxn];
 	struct perf_event_context *next_ctx;
-	struct perf_event_context *parent;
+	struct perf_event_context *parent, *next_parent;
 	struct perf_cpu_context *cpuctx;
 	int do_switch = 1;
 
@@ -2253,10 +2280,18 @@ static void perf_event_context_sched_out(struct task_struct *task, int ctxn,
 		return;
 
 	rcu_read_lock();
-	parent = rcu_dereference(ctx->parent_ctx);
 	next_ctx = next->perf_event_ctxp[ctxn];
-	if (parent && next_ctx &&
-	    rcu_dereference(next_ctx->parent_ctx) == parent) {
+	if (!next_ctx)
+		goto unlock;
+
+	parent = rcu_dereference(ctx->parent_ctx);
+	next_parent = rcu_dereference(next_ctx->parent_ctx);
+
+	/* If neither context have a parent context; they cannot be clones. */
+	if (!parent && !next_parent)
+		goto unlock;
+
+	if (next_parent == ctx || next_ctx == parent || next_parent == parent) {
 		/*
 		 * Looks like the two contexts are clones, so we might be
 		 * able to optimize the context switch.  We lock both
@@ -2284,6 +2319,7 @@ static void perf_event_context_sched_out(struct task_struct *task, int ctxn,
 		raw_spin_unlock(&next_ctx->lock);
 		raw_spin_unlock(&ctx->lock);
 	}
+unlock:
 	rcu_read_unlock();
 
 	if (do_switch) {
@@ -2712,7 +2748,7 @@ static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx,
 
 		hwc = &event->hw;
 
-		if (needs_unthr && hwc->interrupts == MAX_INTERRUPTS) {
+		if (hwc->interrupts == MAX_INTERRUPTS) {
 			hwc->interrupts = 0;
 			perf_log_throttle(event, 1);
 			event->pmu->start(event, 0);
@@ -2811,10 +2847,11 @@ done:
 #ifdef CONFIG_NO_HZ_FULL
 bool perf_event_can_stop_tick(void)
 {
-	if (list_empty(&__get_cpu_var(rotation_list)))
-		return true;
-	else
+	if (atomic_read(&nr_freq_events) ||
+	    __this_cpu_read(perf_throttled_count))
 		return false;
+	else
+		return true;
 }
 #endif
 
@@ -3128,36 +3165,63 @@ static void free_event_rcu(struct rcu_head *head)
 static void ring_buffer_put(struct ring_buffer *rb);
 static void ring_buffer_detach(struct perf_event *event, struct ring_buffer *rb);
 
-static void free_event(struct perf_event *event)
+static void unaccount_event_cpu(struct perf_event *event, int cpu)
 {
-	irq_work_sync(&event->pending);
+	if (event->parent)
+		return;
+
+	if (has_branch_stack(event)) {
+		if (!(event->attach_state & PERF_ATTACH_TASK))
+			atomic_dec(&per_cpu(perf_branch_stack_events, cpu));
+	}
+	if (is_cgroup_event(event))
+		atomic_dec(&per_cpu(perf_cgroup_events, cpu));
+}
+
+static void unaccount_event(struct perf_event *event)
+{
+	if (event->parent)
+		return;
 
+	if (event->attach_state & PERF_ATTACH_TASK)
+		static_key_slow_dec_deferred(&perf_sched_events);
+	if (event->attr.mmap || event->attr.mmap_data)
+		atomic_dec(&nr_mmap_events);
+	if (event->attr.comm)
+		atomic_dec(&nr_comm_events);
+	if (event->attr.task)
+		atomic_dec(&nr_task_events);
+	if (event->attr.freq)
+		atomic_dec(&nr_freq_events);
+	if (is_cgroup_event(event))
+		static_key_slow_dec_deferred(&perf_sched_events);
+	if (has_branch_stack(event))
+		static_key_slow_dec_deferred(&perf_sched_events);
+
+	unaccount_event_cpu(event, event->cpu);
+}
+
+static void __free_event(struct perf_event *event)
+{
 	if (!event->parent) {
-		if (event->attach_state & PERF_ATTACH_TASK)
-			static_key_slow_dec_deferred(&perf_sched_events);
-		if (event->attr.mmap || event->attr.mmap_data)
-			atomic_dec(&nr_mmap_events);
-		if (event->attr.comm)
-			atomic_dec(&nr_comm_events);
-		if (event->attr.task)
-			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));
-			static_key_slow_dec_deferred(&perf_sched_events);
-		}
-
-		if (has_branch_stack(event)) {
-			static_key_slow_dec_deferred(&perf_sched_events);
-			/* is system-wide event */
-			if (!(event->attach_state & PERF_ATTACH_TASK)) {
-				atomic_dec(&per_cpu(perf_branch_stack_events,
-						    event->cpu));
-			}
-		}
 	}
 
+	if (event->destroy)
+		event->destroy(event);
+
+	if (event->ctx)
+		put_ctx(event->ctx);
+
+	call_rcu(&event->rcu_head, free_event_rcu);
+}
+static void free_event(struct perf_event *event)
+{
+	irq_work_sync(&event->pending);
+
+	unaccount_event(event);
+
 	if (event->rb) {
 		struct ring_buffer *rb;
 
@@ -3180,13 +3244,8 @@ static void free_event(struct perf_event *event)
 	if (is_cgroup_event(event))
 		perf_detach_cgroup(event);
 
-	if (event->destroy)
-		event->destroy(event);
-
-	if (event->ctx)
-		put_ctx(event->ctx);
 
-	call_rcu(&event->rcu_head, free_event_rcu);
+	__free_event(event);
 }
 
 int perf_event_release_kernel(struct perf_event *event)
@@ -3544,6 +3603,15 @@ static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	case PERF_EVENT_IOC_PERIOD:
 		return perf_event_period(event, (u64 __user *)arg);
 
+	case PERF_EVENT_IOC_ID:
+	{
+		u64 id = primary_event_id(event);
+
+		if (copy_to_user((void __user *)arg, &id, sizeof(id)))
+			return -EFAULT;
+		return 0;
+	}
+
 	case PERF_EVENT_IOC_SET_OUTPUT:
 	{
 		int ret;
@@ -3625,6 +3693,26 @@ static void calc_timer_values(struct perf_event *event,
 	*running = ctx_time - event->tstamp_running;
 }
 
+static void perf_event_init_userpage(struct perf_event *event)
+{
+	struct perf_event_mmap_page *userpg;
+	struct ring_buffer *rb;
+
+	rcu_read_lock();
+	rb = rcu_dereference(event->rb);
+	if (!rb)
+		goto unlock;
+
+	userpg = rb->user_page;
+
+	/* Allow new userspace to detect that bit 0 is deprecated */
+	userpg->cap_bit0_is_deprecated = 1;
+	userpg->size = offsetof(struct perf_event_mmap_page, __reserved);
+
+unlock:
+	rcu_read_unlock();
+}
+
 void __weak arch_perf_update_userpage(struct perf_event_mmap_page *userpg, u64 now)
 {
 }
@@ -3641,6 +3729,10 @@ void perf_event_update_userpage(struct perf_event *event)
 	u64 enabled, running, now;
 
 	rcu_read_lock();
+	rb = rcu_dereference(event->rb);
+	if (!rb)
+		goto unlock;
+
 	/*
 	 * compute total_time_enabled, total_time_running
 	 * based on snapshot values taken when the event
@@ -3651,12 +3743,8 @@ void perf_event_update_userpage(struct perf_event *event)
 	 * NMI context
 	 */
 	calc_timer_values(event, &now, &enabled, &running);
-	rb = rcu_dereference(event->rb);
-	if (!rb)
-		goto unlock;
 
 	userpg = rb->user_page;
-
 	/*
 	 * Disable preemption so as to not let the corresponding user-space
 	 * spin too long if we get preempted.
@@ -4009,6 +4097,7 @@ again:
 	ring_buffer_attach(event, rb);
 	rcu_assign_pointer(event->rb, rb);
 
+	perf_event_init_userpage(event);
 	perf_event_update_userpage(event);
 
 unlock:
@@ -4251,7 +4340,7 @@ static void __perf_event_header__init_id(struct perf_event_header *header,
 	if (sample_type & PERF_SAMPLE_TIME)
 		data->time = perf_clock();
 
-	if (sample_type & PERF_SAMPLE_ID)
+	if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER))
 		data->id = primary_event_id(event);
 
 	if (sample_type & PERF_SAMPLE_STREAM_ID)
@@ -4290,6 +4379,9 @@ static void __perf_event__output_id_sample(struct perf_output_handle *handle,
 
 	if (sample_type & PERF_SAMPLE_CPU)
 		perf_output_put(handle, data->cpu_entry);
+
+	if (sample_type & PERF_SAMPLE_IDENTIFIER)
+		perf_output_put(handle, data->id);
 }
 
 void perf_event__output_id_sample(struct perf_event *event,
@@ -4355,7 +4447,8 @@ static void perf_output_read_group(struct perf_output_handle *handle,
 	list_for_each_entry(sub, &leader->sibling_list, group_entry) {
 		n = 0;
 
-		if (sub != event)
+		if ((sub != event) &&
+		    (sub->state == PERF_EVENT_STATE_ACTIVE))
 			sub->pmu->read(sub);
 
 		values[n++] = perf_event_count(sub);
@@ -4402,6 +4495,9 @@ void perf_output_sample(struct perf_output_handle *handle,
 
 	perf_output_put(handle, *header);
 
+	if (sample_type & PERF_SAMPLE_IDENTIFIER)
+		perf_output_put(handle, data->id);
+
 	if (sample_type & PERF_SAMPLE_IP)
 		perf_output_put(handle, data->ip);
 
@@ -4462,20 +4558,6 @@ void perf_output_sample(struct perf_output_handle *handle,
 		}
 	}
 
-	if (!event->attr.watermark) {
-		int wakeup_events = event->attr.wakeup_events;
-
-		if (wakeup_events) {
-			struct ring_buffer *rb = handle->rb;
-			int events = local_inc_return(&rb->events);
-
-			if (events >= wakeup_events) {
-				local_sub(wakeup_events, &rb->events);
-				local_inc(&rb->wakeup);
-			}
-		}
-	}
-
 	if (sample_type & PERF_SAMPLE_BRANCH_STACK) {
 		if (data->br_stack) {
 			size_t size;
@@ -4511,16 +4593,34 @@ void perf_output_sample(struct perf_output_handle *handle,
 		}
 	}
 
-	if (sample_type & PERF_SAMPLE_STACK_USER)
+	if (sample_type & PERF_SAMPLE_STACK_USER) {
 		perf_output_sample_ustack(handle,
 					  data->stack_user_size,
 					  data->regs_user.regs);
+	}
 
 	if (sample_type & PERF_SAMPLE_WEIGHT)
 		perf_output_put(handle, data->weight);
 
 	if (sample_type & PERF_SAMPLE_DATA_SRC)
 		perf_output_put(handle, data->data_src.val);
+
+	if (sample_type & PERF_SAMPLE_TRANSACTION)
+		perf_output_put(handle, data->txn);
+
+	if (!event->attr.watermark) {
+		int wakeup_events = event->attr.wakeup_events;
+
+		if (wakeup_events) {
+			struct ring_buffer *rb = handle->rb;
+			int events = local_inc_return(&rb->events);
+
+			if (events >= wakeup_events) {
+				local_sub(wakeup_events, &rb->events);
+				local_inc(&rb->wakeup);
+			}
+		}
+	}
 }
 
 void perf_prepare_sample(struct perf_event_header *header,
@@ -4680,12 +4780,10 @@ perf_event_read_event(struct perf_event *event,
 	perf_output_end(&handle);
 }
 
-typedef int  (perf_event_aux_match_cb)(struct perf_event *event, void *data);
 typedef void (perf_event_aux_output_cb)(struct perf_event *event, void *data);
 
 static void
 perf_event_aux_ctx(struct perf_event_context *ctx,
-		   perf_event_aux_match_cb match,
 		   perf_event_aux_output_cb output,
 		   void *data)
 {
@@ -4696,15 +4794,12 @@ perf_event_aux_ctx(struct perf_event_context *ctx,
 			continue;
 		if (!event_filter_match(event))
 			continue;
-		if (match(event, data))
-			output(event, data);
+		output(event, data);
 	}
 }
 
 static void
-perf_event_aux(perf_event_aux_match_cb match,
-	       perf_event_aux_output_cb output,
-	       void *data,
+perf_event_aux(perf_event_aux_output_cb output, void *data,
 	       struct perf_event_context *task_ctx)
 {
 	struct perf_cpu_context *cpuctx;
@@ -4717,7 +4812,7 @@ perf_event_aux(perf_event_aux_match_cb match,
 		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
 		if (cpuctx->unique_pmu != pmu)
 			goto next;
-		perf_event_aux_ctx(&cpuctx->ctx, match, output, data);
+		perf_event_aux_ctx(&cpuctx->ctx, output, data);
 		if (task_ctx)
 			goto next;
 		ctxn = pmu->task_ctx_nr;
@@ -4725,14 +4820,14 @@ perf_event_aux(perf_event_aux_match_cb match,
 			goto next;
 		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
 		if (ctx)
-			perf_event_aux_ctx(ctx, match, output, data);
+			perf_event_aux_ctx(ctx, output, data);
 next:
 		put_cpu_ptr(pmu->pmu_cpu_context);
 	}
 
 	if (task_ctx) {
 		preempt_disable();
-		perf_event_aux_ctx(task_ctx, match, output, data);
+		perf_event_aux_ctx(task_ctx, output, data);
 		preempt_enable();
 	}
 	rcu_read_unlock();
@@ -4741,7 +4836,7 @@ next:
 /*
  * task tracking -- fork/exit
  *
- * enabled by: attr.comm | attr.mmap | attr.mmap_data | attr.task
+ * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task
  */
 
 struct perf_task_event {
@@ -4759,6 +4854,13 @@ struct perf_task_event {
 	} event_id;
 };
 
+static int perf_event_task_match(struct perf_event *event)
+{
+	return event->attr.comm  || event->attr.mmap ||
+	       event->attr.mmap2 || event->attr.mmap_data ||
+	       event->attr.task;
+}
+
 static void perf_event_task_output(struct perf_event *event,
 				   void *data)
 {
@@ -4768,6 +4870,9 @@ static void perf_event_task_output(struct perf_event *event,
 	struct task_struct *task = task_event->task;
 	int ret, size = task_event->event_id.header.size;
 
+	if (!perf_event_task_match(event))
+		return;
+
 	perf_event_header__init_id(&task_event->event_id.header, &sample, event);
 
 	ret = perf_output_begin(&handle, event,
@@ -4790,13 +4895,6 @@ out:
 	task_event->event_id.header.size = size;
 }
 
-static int perf_event_task_match(struct perf_event *event,
-				 void *data __maybe_unused)
-{
-	return event->attr.comm || event->attr.mmap ||
-	       event->attr.mmap_data || event->attr.task;
-}
-
 static void perf_event_task(struct task_struct *task,
 			      struct perf_event_context *task_ctx,
 			      int new)
@@ -4825,8 +4923,7 @@ static void perf_event_task(struct task_struct *task,
 		},
 	};
 
-	perf_event_aux(perf_event_task_match,
-		       perf_event_task_output,
+	perf_event_aux(perf_event_task_output,
 		       &task_event,
 		       task_ctx);
 }
@@ -4853,6 +4950,11 @@ struct perf_comm_event {
 	} event_id;
 };
 
+static int perf_event_comm_match(struct perf_event *event)
+{
+	return event->attr.comm;
+}
+
 static void perf_event_comm_output(struct perf_event *event,
 				   void *data)
 {
@@ -4862,6 +4964,9 @@ static void perf_event_comm_output(struct perf_event *event,
 	int size = comm_event->event_id.header.size;
 	int ret;
 
+	if (!perf_event_comm_match(event))
+		return;
+
 	perf_event_header__init_id(&comm_event->event_id.header, &sample, event);
 	ret = perf_output_begin(&handle, event,
 				comm_event->event_id.header.size);
@@ -4883,12 +4988,6 @@ out:
 	comm_event->event_id.header.size = size;
 }
 
-static int perf_event_comm_match(struct perf_event *event,
-				 void *data __maybe_unused)
-{
-	return event->attr.comm;
-}
-
 static void perf_event_comm_event(struct perf_comm_event *comm_event)
 {
 	char comm[TASK_COMM_LEN];
@@ -4903,8 +5002,7 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
 
 	comm_event->event_id.header.size = sizeof(comm_event->event_id) + size;
 
-	perf_event_aux(perf_event_comm_match,
-		       perf_event_comm_output,
+	perf_event_aux(perf_event_comm_output,
 		       comm_event,
 		       NULL);
 }
@@ -4955,6 +5053,9 @@ struct perf_mmap_event {
 
 	const char		*file_name;
 	int			file_size;
+	int			maj, min;
+	u64			ino;
+	u64			ino_generation;
 
 	struct {
 		struct perf_event_header	header;
@@ -4967,6 +5068,17 @@ struct perf_mmap_event {
 	} event_id;
 };
 
+static int perf_event_mmap_match(struct perf_event *event,
+				 void *data)
+{
+	struct perf_mmap_event *mmap_event = data;
+	struct vm_area_struct *vma = mmap_event->vma;
+	int executable = vma->vm_flags & VM_EXEC;
+
+	return (!executable && event->attr.mmap_data) ||
+	       (executable && (event->attr.mmap || event->attr.mmap2));
+}
+
 static void perf_event_mmap_output(struct perf_event *event,
 				   void *data)
 {
@@ -4976,6 +5088,17 @@ static void perf_event_mmap_output(struct perf_event *event,
 	int size = mmap_event->event_id.header.size;
 	int ret;
 
+	if (!perf_event_mmap_match(event, data))
+		return;
+
+	if (event->attr.mmap2) {
+		mmap_event->event_id.header.type = PERF_RECORD_MMAP2;
+		mmap_event->event_id.header.size += sizeof(mmap_event->maj);
+		mmap_event->event_id.header.size += sizeof(mmap_event->min);
+		mmap_event->event_id.header.size += sizeof(mmap_event->ino);
+		mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation);
+	}
+
 	perf_event_header__init_id(&mmap_event->event_id.header, &sample, event);
 	ret = perf_output_begin(&handle, event,
 				mmap_event->event_id.header.size);
@@ -4986,6 +5109,14 @@ static void perf_event_mmap_output(struct perf_event *event,
 	mmap_event->event_id.tid = perf_event_tid(event, current);
 
 	perf_output_put(&handle, mmap_event->event_id);
+
+	if (event->attr.mmap2) {
+		perf_output_put(&handle, mmap_event->maj);
+		perf_output_put(&handle, mmap_event->min);
+		perf_output_put(&handle, mmap_event->ino);
+		perf_output_put(&handle, mmap_event->ino_generation);
+	}
+
 	__output_copy(&handle, mmap_event->file_name,
 				   mmap_event->file_size);
 
@@ -4996,82 +5127,89 @@ out:
 	mmap_event->event_id.header.size = size;
 }
 
-static int perf_event_mmap_match(struct perf_event *event,
-				 void *data)
-{
-	struct perf_mmap_event *mmap_event = data;
-	struct vm_area_struct *vma = mmap_event->vma;
-	int executable = vma->vm_flags & VM_EXEC;
-
-	return (!executable && event->attr.mmap_data) ||
-	       (executable && event->attr.mmap);
-}
-
 static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
 {
 	struct vm_area_struct *vma = mmap_event->vma;
 	struct file *file = vma->vm_file;
+	int maj = 0, min = 0;
+	u64 ino = 0, gen = 0;
 	unsigned int size;
 	char tmp[16];
 	char *buf = NULL;
-	const char *name;
-
-	memset(tmp, 0, sizeof(tmp));
+	char *name;
 
 	if (file) {
+		struct inode *inode;
+		dev_t dev;
+
+		buf = kmalloc(PATH_MAX, GFP_KERNEL);
+		if (!buf) {
+			name = "//enomem";
+			goto cpy_name;
+		}
 		/*
-		 * d_path works from the end of the rb backwards, so we
+		 * d_path() works from the end of the rb backwards, so we
 		 * need to add enough zero bytes after the string to handle
 		 * the 64bit alignment we do later.
 		 */
-		buf = kzalloc(PATH_MAX + sizeof(u64), GFP_KERNEL);
-		if (!buf) {
-			name = strncpy(tmp, "//enomem", sizeof(tmp));
-			goto got_name;
-		}
-		name = d_path(&file->f_path, buf, PATH_MAX);
+		name = d_path(&file->f_path, buf, PATH_MAX - sizeof(u64));
 		if (IS_ERR(name)) {
-			name = strncpy(tmp, "//toolong", sizeof(tmp));
-			goto got_name;
+			name = "//toolong";
+			goto cpy_name;
 		}
+		inode = file_inode(vma->vm_file);
+		dev = inode->i_sb->s_dev;
+		ino = inode->i_ino;
+		gen = inode->i_generation;
+		maj = MAJOR(dev);
+		min = MINOR(dev);
+		goto got_name;
 	} else {
-		if (arch_vma_name(mmap_event->vma)) {
-			name = strncpy(tmp, arch_vma_name(mmap_event->vma),
-				       sizeof(tmp) - 1);
-			tmp[sizeof(tmp) - 1] = '\0';
-			goto got_name;
-		}
+		name = (char *)arch_vma_name(vma);
+		if (name)
+			goto cpy_name;
 
-		if (!vma->vm_mm) {
-			name = strncpy(tmp, "[vdso]", sizeof(tmp));
-			goto got_name;
-		} else if (vma->vm_start <= vma->vm_mm->start_brk &&
+		if (vma->vm_start <= vma->vm_mm->start_brk &&
 				vma->vm_end >= vma->vm_mm->brk) {
-			name = strncpy(tmp, "[heap]", sizeof(tmp));
-			goto got_name;
-		} else if (vma->vm_start <= vma->vm_mm->start_stack &&
+			name = "[heap]";
+			goto cpy_name;
+		}
+		if (vma->vm_start <= vma->vm_mm->start_stack &&
 				vma->vm_end >= vma->vm_mm->start_stack) {
-			name = strncpy(tmp, "[stack]", sizeof(tmp));
-			goto got_name;
+			name = "[stack]";
+			goto cpy_name;
 		}
 
-		name = strncpy(tmp, "//anon", sizeof(tmp));
-		goto got_name;
+		name = "//anon";
+		goto cpy_name;
 	}
 
+cpy_name:
+	strlcpy(tmp, name, sizeof(tmp));
+	name = tmp;
 got_name:
-	size = ALIGN(strlen(name)+1, sizeof(u64));
+	/*
+	 * Since our buffer works in 8 byte units we need to align our string
+	 * size to a multiple of 8. However, we must guarantee the tail end is
+	 * zero'd out to avoid leaking random bits to userspace.
+	 */
+	size = strlen(name)+1;
+	while (!IS_ALIGNED(size, sizeof(u64)))
+		name[size++] = '\0';
 
 	mmap_event->file_name = name;
 	mmap_event->file_size = size;
+	mmap_event->maj = maj;
+	mmap_event->min = min;
+	mmap_event->ino = ino;
+	mmap_event->ino_generation = gen;
 
 	if (!(vma->vm_flags & VM_EXEC))
 		mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA;
 
 	mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size;
 
-	perf_event_aux(perf_event_mmap_match,
-		       perf_event_mmap_output,
+	perf_event_aux(perf_event_mmap_output,
 		       mmap_event,
 		       NULL);
 
@@ -5101,6 +5239,10 @@ void perf_event_mmap(struct vm_area_struct *vma)
 			.len    = vma->vm_end - vma->vm_start,
 			.pgoff  = (u64)vma->vm_pgoff << PAGE_SHIFT,
 		},
+		/* .maj (attr_mmap2 only) */
+		/* .min (attr_mmap2 only) */
+		/* .ino (attr_mmap2 only) */
+		/* .ino_generation (attr_mmap2 only) */
 	};
 
 	perf_event_mmap_event(&mmap_event);
@@ -5178,6 +5320,7 @@ static int __perf_event_overflow(struct perf_event *event,
 			__this_cpu_inc(perf_throttled_count);
 			hwc->interrupts = MAX_INTERRUPTS;
 			perf_log_throttle(event, 0);
+			tick_nohz_full_kick();
 			ret = 1;
 		}
 	}
@@ -6189,6 +6332,7 @@ type_show(struct device *dev, struct device_attribute *attr, char *page)
 
 	return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type);
 }
+static DEVICE_ATTR_RO(type);
 
 static ssize_t
 perf_event_mux_interval_ms_show(struct device *dev,
@@ -6233,17 +6377,19 @@ perf_event_mux_interval_ms_store(struct device *dev,
 
 	return count;
 }
+static DEVICE_ATTR_RW(perf_event_mux_interval_ms);
 
-static struct device_attribute pmu_dev_attrs[] = {
-	__ATTR_RO(type),
-	__ATTR_RW(perf_event_mux_interval_ms),
-	__ATTR_NULL,
+static struct attribute *pmu_dev_attrs[] = {
+	&dev_attr_type.attr,
+	&dev_attr_perf_event_mux_interval_ms.attr,
+	NULL,
 };
+ATTRIBUTE_GROUPS(pmu_dev);
 
 static int pmu_bus_running;
 static struct bus_type pmu_bus = {
 	.name		= "event_source",
-	.dev_attrs	= pmu_dev_attrs,
+	.dev_groups	= pmu_dev_groups,
 };
 
 static void pmu_dev_release(struct device *dev)
@@ -6443,6 +6589,44 @@ unlock:
 	return pmu;
 }
 
+static void account_event_cpu(struct perf_event *event, int cpu)
+{
+	if (event->parent)
+		return;
+
+	if (has_branch_stack(event)) {
+		if (!(event->attach_state & PERF_ATTACH_TASK))
+			atomic_inc(&per_cpu(perf_branch_stack_events, cpu));
+	}
+	if (is_cgroup_event(event))
+		atomic_inc(&per_cpu(perf_cgroup_events, cpu));
+}
+
+static void account_event(struct perf_event *event)
+{
+	if (event->parent)
+		return;
+
+	if (event->attach_state & PERF_ATTACH_TASK)
+		static_key_slow_inc(&perf_sched_events.key);
+	if (event->attr.mmap || event->attr.mmap_data)
+		atomic_inc(&nr_mmap_events);
+	if (event->attr.comm)
+		atomic_inc(&nr_comm_events);
+	if (event->attr.task)
+		atomic_inc(&nr_task_events);
+	if (event->attr.freq) {
+		if (atomic_inc_return(&nr_freq_events) == 1)
+			tick_nohz_full_kick_all();
+	}
+	if (has_branch_stack(event))
+		static_key_slow_inc(&perf_sched_events.key);
+	if (is_cgroup_event(event))
+		static_key_slow_inc(&perf_sched_events.key);
+
+	account_event_cpu(event, event->cpu);
+}
+
 /*
  * Allocate and initialize a event structure
  */
@@ -6457,7 +6641,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
 	struct pmu *pmu;
 	struct perf_event *event;
 	struct hw_perf_event *hwc;
-	long err;
+	long err = -EINVAL;
 
 	if ((unsigned)cpu >= nr_cpu_ids) {
 		if (!task || cpu != -1)
@@ -6540,49 +6724,35 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
 	 * we currently do not support PERF_FORMAT_GROUP on inherited events
 	 */
 	if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP))
-		goto done;
+		goto err_ns;
 
 	pmu = perf_init_event(event);
-
-done:
-	err = 0;
 	if (!pmu)
-		err = -EINVAL;
-	else if (IS_ERR(pmu))
+		goto err_ns;
+	else if (IS_ERR(pmu)) {
 		err = PTR_ERR(pmu);
-
-	if (err) {
-		if (event->ns)
-			put_pid_ns(event->ns);
-		kfree(event);
-		return ERR_PTR(err);
+		goto err_ns;
 	}
 
 	if (!event->parent) {
-		if (event->attach_state & PERF_ATTACH_TASK)
-			static_key_slow_inc(&perf_sched_events.key);
-		if (event->attr.mmap || event->attr.mmap_data)
-			atomic_inc(&nr_mmap_events);
-		if (event->attr.comm)
-			atomic_inc(&nr_comm_events);
-		if (event->attr.task)
-			atomic_inc(&nr_task_events);
 		if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) {
 			err = get_callchain_buffers();
-			if (err) {
-				free_event(event);
-				return ERR_PTR(err);
-			}
-		}
-		if (has_branch_stack(event)) {
-			static_key_slow_inc(&perf_sched_events.key);
-			if (!(event->attach_state & PERF_ATTACH_TASK))
-				atomic_inc(&per_cpu(perf_branch_stack_events,
-						    event->cpu));
+			if (err)
+				goto err_pmu;
 		}
 	}
 
 	return event;
+
+err_pmu:
+	if (event->destroy)
+		event->destroy(event);
+err_ns:
+	if (event->ns)
+		put_pid_ns(event->ns);
+	kfree(event);
+
+	return ERR_PTR(err);
 }
 
 static int perf_copy_attr(struct perf_event_attr __user *uattr,
@@ -6640,6 +6810,10 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr,
 	if (ret)
 		return -EFAULT;
 
+	/* disabled for now */
+	if (attr->mmap2)
+		return -EINVAL;
+
 	if (attr->__reserved_1)
 		return -EINVAL;
 
@@ -6864,17 +7038,14 @@ SYSCALL_DEFINE5(perf_event_open,
 
 	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));
-		static_key_slow_inc(&perf_sched_events.key);
+		if (err) {
+			__free_event(event);
+			goto err_task;
+		}
 	}
 
+	account_event(event);
+
 	/*
 	 * Special case software events and allow them to be part of
 	 * any hardware group.
@@ -6998,7 +7169,6 @@ SYSCALL_DEFINE5(perf_event_open,
 	}
 
 	perf_install_in_context(ctx, event, event->cpu);
-	++ctx->generation;
 	perf_unpin_context(ctx);
 	mutex_unlock(&ctx->mutex);
 
@@ -7070,6 +7240,8 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
 		goto err;
 	}
 
+	account_event(event);
+
 	ctx = find_get_context(event->pmu, task, cpu);
 	if (IS_ERR(ctx)) {
 		err = PTR_ERR(ctx);
@@ -7079,7 +7251,6 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
 	WARN_ON_ONCE(ctx->parent_ctx);
 	mutex_lock(&ctx->mutex);
 	perf_install_in_context(ctx, event, cpu);
-	++ctx->generation;
 	perf_unpin_context(ctx);
 	mutex_unlock(&ctx->mutex);
 
@@ -7106,18 +7277,20 @@ void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu)
 	list_for_each_entry_safe(event, tmp, &src_ctx->event_list,
 				 event_entry) {
 		perf_remove_from_context(event);
+		unaccount_event_cpu(event, src_cpu);
 		put_ctx(src_ctx);
-		list_add(&event->event_entry, &events);
+		list_add(&event->migrate_entry, &events);
 	}
 	mutex_unlock(&src_ctx->mutex);
 
 	synchronize_rcu();
 
 	mutex_lock(&dst_ctx->mutex);
-	list_for_each_entry_safe(event, tmp, &events, event_entry) {
-		list_del(&event->event_entry);
+	list_for_each_entry_safe(event, tmp, &events, migrate_entry) {
+		list_del(&event->migrate_entry);
 		if (event->state >= PERF_EVENT_STATE_OFF)
 			event->state = PERF_EVENT_STATE_INACTIVE;
+		account_event_cpu(event, dst_cpu);
 		perf_install_in_context(dst_ctx, event, dst_cpu);
 		get_ctx(dst_ctx);
 	}
@@ -7798,7 +7971,8 @@ unlock:
 device_initcall(perf_event_sysfs_init);
 
 #ifdef CONFIG_CGROUP_PERF
-static struct cgroup_subsys_state *perf_cgroup_css_alloc(struct cgroup *cont)
+static struct cgroup_subsys_state *
+perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
 {
 	struct perf_cgroup *jc;
 
@@ -7815,11 +7989,10 @@ static struct cgroup_subsys_state *perf_cgroup_css_alloc(struct cgroup *cont)
 	return &jc->css;
 }
 
-static void perf_cgroup_css_free(struct cgroup *cont)
+static void perf_cgroup_css_free(struct cgroup_subsys_state *css)
 {
-	struct perf_cgroup *jc;
-	jc = container_of(cgroup_subsys_state(cont, perf_subsys_id),
-			  struct perf_cgroup, css);
+	struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css);
+
 	free_percpu(jc->info);
 	kfree(jc);
 }
@@ -7831,15 +8004,17 @@ static int __perf_cgroup_move(void *info)
 	return 0;
 }
 
-static void perf_cgroup_attach(struct cgroup *cgrp, struct cgroup_taskset *tset)
+static void perf_cgroup_attach(struct cgroup_subsys_state *css,
+			       struct cgroup_taskset *tset)
 {
 	struct task_struct *task;
 
-	cgroup_taskset_for_each(task, cgrp, tset)
+	cgroup_taskset_for_each(task, css, tset)
 		task_function_call(task, __perf_cgroup_move, task);
 }
 
-static void perf_cgroup_exit(struct cgroup *cgrp, struct cgroup *old_cgrp,
+static void perf_cgroup_exit(struct cgroup_subsys_state *css,
+			     struct cgroup_subsys_state *old_css,
 			     struct task_struct *task)
 {
 	/*