leds: Use all-in-one vtime aware kcpustat accessor

We can now safely read user kcpustat fields on nohz_full CPUs.
Use the appropriate accessor.

[ mingo: Fixed build failure. ]

Reported-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com> (maintainer:LED SUBSYSTEM)
Cc: Pavel Machek <pavel@ucw.cz> (maintainer:LED SUBSYSTEM)
Cc: Dan Murphy <dmurphy@ti.com> (reviewer:LED SUBSYSTEM)
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Link: https://lkml.kernel.org/r/20191121024430.19938-6-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

drivers/leds/trigger/ledtrig-activity.c

@@ -57,11 +57,15 @@ static void led_activity_function(struct timer_list *t)
 	curr_used = 0;
 
 	for_each_possible_cpu(i) {
-		curr_used += kcpustat_cpu(i).cpustat[CPUTIME_USER]
-			  +  kcpustat_cpu(i).cpustat[CPUTIME_NICE]
-			  +  kcpustat_field(&kcpustat_cpu(i), CPUTIME_SYSTEM, i)
-			  +  kcpustat_cpu(i).cpustat[CPUTIME_SOFTIRQ]
-			  +  kcpustat_cpu(i).cpustat[CPUTIME_IRQ];
+		struct kernel_cpustat kcpustat;
+
+		kcpustat_cpu_fetch(&kcpustat, i);
+
+		curr_used += kcpustat.cpustat[CPUTIME_USER]
+			  +  kcpustat.cpustat[CPUTIME_NICE]
+			  +  kcpustat.cpustat[CPUTIME_SYSTEM]
+			  +  kcpustat.cpustat[CPUTIME_SOFTIRQ]
+			  +  kcpustat.cpustat[CPUTIME_IRQ];
 		cpus++;
 	}