[PATCH 21/25] procfs: Use vtime aware kcpustat accessor

[Frederic Weisbecker]

Now that we have a vtime safe kcpustat accessor, use it to fix frozen
kcpustat values on nohz_full CPUs.

Reported-by: Yauheni Kaliuta <yauheni.kali...@redhat.com>
Signed-off-by: Frederic Weisbecker <frede...@kernel.org>
Cc: Yauheni Kaliuta <yauheni.kali...@redhat.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Rik van Riel <r...@redhat.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Wanpeng Li <wanpen...@tencent.com>
Cc: Ingo Molnar <mi...@kernel.org>
---
 fs/proc/stat.c | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/fs/proc/stat.c b/fs/proc/stat.c
index 535eda7..2eed662 100644
--- a/fs/proc/stat.c
+++ b/fs/proc/stat.c
@@ -95,16 +95,20 @@ static int show_stat(struct seq_file *p, void *v)
        getboottime64(&boottime);
 
        for_each_possible_cpu(i) {
-               user += kcpustat_cpu(i).cpustat[CPUTIME_USER];
-               nice += kcpustat_cpu(i).cpustat[CPUTIME_NICE];
-               system += kcpustat_cpu(i).cpustat[CPUTIME_SYSTEM];
+               u64 cpu_user, cpu_nice, cpu_sys, cpu_guest, cpu_guest_nice;
+
+               kcpustat_cputime(&kcpustat_cpu(i), i, &cpu_user, &cpu_nice,
+                                &cpu_sys, &cpu_guest, &cpu_guest_nice);
+               user += cpu_user;
+               nice += cpu_nice;
+               system += cpu_sys;
                idle += get_idle_time(i);
                iowait += get_iowait_time(i);
                irq += kcpustat_cpu(i).cpustat[CPUTIME_IRQ];
                softirq += kcpustat_cpu(i).cpustat[CPUTIME_SOFTIRQ];
                steal += kcpustat_cpu(i).cpustat[CPUTIME_STEAL];
-               guest += kcpustat_cpu(i).cpustat[CPUTIME_GUEST];
-               guest_nice += kcpustat_cpu(i).cpustat[CPUTIME_GUEST_NICE];
+               guest += cpu_guest;
+               guest_nice += guest_nice;
                sum += kstat_cpu_irqs_sum(i);
                sum += arch_irq_stat_cpu(i);
 
@@ -130,17 +134,14 @@ static int show_stat(struct seq_file *p, void *v)
        seq_putc(p, '\n');
 
        for_each_online_cpu(i) {
+               kcpustat_cputime(&kcpustat_cpu(i), i, &user, &nice,
+                                &system, &guest, &guest_nice);
                /* Copy values here to work around gcc-2.95.3, gcc-2.96 */
-               user = kcpustat_cpu(i).cpustat[CPUTIME_USER];
-               nice = kcpustat_cpu(i).cpustat[CPUTIME_NICE];
-               system = kcpustat_cpu(i).cpustat[CPUTIME_SYSTEM];
                idle = get_idle_time(i);
                iowait = get_iowait_time(i);
                irq = kcpustat_cpu(i).cpustat[CPUTIME_IRQ];
                softirq = kcpustat_cpu(i).cpustat[CPUTIME_SOFTIRQ];
                steal = kcpustat_cpu(i).cpustat[CPUTIME_STEAL];
-               guest = kcpustat_cpu(i).cpustat[CPUTIME_GUEST];
-               guest_nice = kcpustat_cpu(i).cpustat[CPUTIME_GUEST_NICE];
                seq_printf(p, "cpu%d", i);
                seq_put_decimal_ull(p, " ", nsec_to_clock_t(user));
                seq_put_decimal_ull(p, " ", nsec_to_clock_t(nice));
-- 
2.7.4