1 files changed, 38 insertions, 29 deletions

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 247979a1b815..81e2a388a0f6 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -20,6 +20,7 @@
 #include <linux/gfp.h>
 #include <linux/suspend.h>
 #include <linux/lockdep.h>
+#include <trace/events/power.h>
 
 #include "smpboot.h"
 
@@ -273,22 +274,28 @@ void clear_tasks_mm_cpumask(int cpu)
 	rcu_read_unlock();
 }
 
-static inline void check_for_tasks(int cpu)
+static inline void check_for_tasks(int dead_cpu)
 {
-	struct task_struct *p;
-	cputime_t utime, stime;
+	struct task_struct *g, *p;
 
-	write_lock_irq(&tasklist_lock);
-	for_each_process(p) {
-		task_cputime(p, &utime, &stime);
-		if (task_cpu(p) == cpu && p->state == TASK_RUNNING &&
-		    (utime || stime))
-			printk(KERN_WARNING "Task %s (pid = %d) is on cpu %d "
-				"(state = %ld, flags = %x)\n",
-				p->comm, task_pid_nr(p), cpu,
-				p->state, p->flags);
-	}
-	write_unlock_irq(&tasklist_lock);
+	read_lock_irq(&tasklist_lock);
+	do_each_thread(g, p) {
+		if (!p->on_rq)
+			continue;
+		/*
+		 * We do the check with unlocked task_rq(p)->lock.
+		 * Order the reading to do not warn about a task,
+		 * which was running on this cpu in the past, and
+		 * it's just been woken on another cpu.
+		 */
+		rmb();
+		if (task_cpu(p) != dead_cpu)
+			continue;
+
+		pr_warn("Task %s (pid=%d) is on cpu %d (state=%ld, flags=%x)\n",
+			p->comm, task_pid_nr(p), dead_cpu, p->state, p->flags);
+	} while_each_thread(g, p);
+	read_unlock_irq(&tasklist_lock);
 }
 
 struct take_cpu_down_param {
@@ -336,8 +343,8 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
 	if (err) {
 		nr_calls--;
 		__cpu_notify(CPU_DOWN_FAILED | mod, hcpu, nr_calls, NULL);
-		printk("%s: attempt to take down CPU %u failed\n",
-				__func__, cpu);
+		pr_warn("%s: attempt to take down CPU %u failed\n",
+			__func__, cpu);
 		goto out_release;
 	}
 
@@ -444,8 +451,8 @@ static int _cpu_up(unsigned int cpu, int tasks_frozen)
 	ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls);
 	if (ret) {
 		nr_calls--;
-		printk(KERN_WARNING "%s: attempt to bring up CPU %u failed\n",
-				__func__, cpu);
+		pr_warn("%s: attempt to bring up CPU %u failed\n",
+			__func__, cpu);
 		goto out_notify;
 	}
 
@@ -475,11 +482,10 @@ int cpu_up(unsigned int cpu)
 	int err = 0;
 
 	if (!cpu_possible(cpu)) {
-		printk(KERN_ERR "can't online cpu %d because it is not "
-			"configured as may-hotadd at boot time\n", cpu);
+		pr_err("can't online cpu %d because it is not configured as may-hotadd at boot time\n",
+		       cpu);
 #if defined(CONFIG_IA64)
-		printk(KERN_ERR "please check additional_cpus= boot "
-				"parameter\n");
+		pr_err("please check additional_cpus= boot parameter\n");
 #endif
 		return -EINVAL;
 	}
@@ -518,16 +524,17 @@ int disable_nonboot_cpus(void)
 	 */
 	cpumask_clear(frozen_cpus);
 
-	printk("Disabling non-boot CPUs ...\n");
+	pr_info("Disabling non-boot CPUs ...\n");
 	for_each_online_cpu(cpu) {
 		if (cpu == first_cpu)
 			continue;
+		trace_suspend_resume(TPS("CPU_OFF"), cpu, true);
 		error = _cpu_down(cpu, 1);
+		trace_suspend_resume(TPS("CPU_OFF"), cpu, false);
 		if (!error)
 			cpumask_set_cpu(cpu, frozen_cpus);
 		else {
-			printk(KERN_ERR "Error taking CPU%d down: %d\n",
-				cpu, error);
+			pr_err("Error taking CPU%d down: %d\n", cpu, error);
 			break;
 		}
 	}
@@ -537,7 +544,7 @@ int disable_nonboot_cpus(void)
 		/* Make sure the CPUs won't be enabled by someone else */
 		cpu_hotplug_disabled = 1;
 	} else {
-		printk(KERN_ERR "Non-boot CPUs are not disabled\n");
+		pr_err("Non-boot CPUs are not disabled\n");
 	}
 	cpu_maps_update_done();
 	return error;
@@ -561,17 +568,19 @@ void __ref enable_nonboot_cpus(void)
 	if (cpumask_empty(frozen_cpus))
 		goto out;
 
-	printk(KERN_INFO "Enabling non-boot CPUs ...\n");
+	pr_info("Enabling non-boot CPUs ...\n");
 
 	arch_enable_nonboot_cpus_begin();
 
 	for_each_cpu(cpu, frozen_cpus) {
+		trace_suspend_resume(TPS("CPU_ON"), cpu, true);
 		error = _cpu_up(cpu, 1);
+		trace_suspend_resume(TPS("CPU_ON"), cpu, false);
 		if (!error) {
-			printk(KERN_INFO "CPU%d is up\n", cpu);
+			pr_info("CPU%d is up\n", cpu);
 			continue;
 		}
-		printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error);
+		pr_warn("Error taking CPU%d up: %d\n", cpu, error);
 	}
 
 	arch_enable_nonboot_cpus_end();