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>
---
 drivers/cpufreq/cpufreq.c          | 18 +++++++++++-------
 drivers/cpufreq/cpufreq_governor.c | 27 ++++++++++++++++++++-------
 2 files changed, 31 insertions(+), 14 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 7aa3dca..e9cff3f 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -119,18 +119,22 @@ EXPORT_SYMBOL_GPL(get_governor_parent_kobj);
 
 static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall)
 {
-       u64 idle_time;
+       struct kernel_cpustat *kcpustat = &kcpustat_cpu(cpu);
+       u64 user, nice, sys, guest, guest_nice;
        u64 cur_wall_time;
+       u64 idle_time;
        u64 busy_time;
 
        cur_wall_time = jiffies64_to_nsecs(get_jiffies_64());
 
-       busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER];
-       busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM];
-       busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ];
-       busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ];
-       busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL];
-       busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE];
+       kcpustat_cputime(kcpustat, cpu, &user, &nice, &sys,
+                        &guest, &guest_nice);
+       busy_time = user;
+       busy_time += sys;
+       busy_time += kcpustat->cpustat[CPUTIME_IRQ];
+       busy_time += kcpustat->cpustat[CPUTIME_SOFTIRQ];
+       busy_time += kcpustat->cpustat[CPUTIME_STEAL];
+       busy_time += nice;
 
        idle_time = cur_wall_time - busy_time;
        if (wall)
diff --git a/drivers/cpufreq/cpufreq_governor.c 
b/drivers/cpufreq/cpufreq_governor.c
index 6d53f7d..5ebe726 100644
--- a/drivers/cpufreq/cpufreq_governor.c
+++ b/drivers/cpufreq/cpufreq_governor.c
@@ -107,8 +107,13 @@ void gov_update_cpu_data(struct dbs_data *dbs_data)
 
                        j_cdbs->prev_cpu_idle = get_cpu_idle_time(j, 
&j_cdbs->prev_update_time,
                                                                  
dbs_data->io_is_busy);
-                       if (dbs_data->ignore_nice_load)
-                               j_cdbs->prev_cpu_nice = 
kcpustat_cpu(j).cpustat[CPUTIME_NICE];
+                       if (dbs_data->ignore_nice_load) {
+                               u64 user, nice, sys, guest, guest_nice;
+
+                               kcpustat_cputime(&kcpustat_cpu(j), j, &user, 
&nice, &sys,
+                                                &guest, &guest_nice);
+                               j_cdbs->prev_cpu_nice = nice;
+                       }
                }
        }
 }
@@ -152,10 +157,13 @@ unsigned int dbs_update(struct cpufreq_policy *policy)
                j_cdbs->prev_cpu_idle = cur_idle_time;
 
                if (ignore_nice) {
-                       u64 cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE];
+                       u64 user, nice, sys, guest, guest_nice;
 
-                       idle_time += div_u64(cur_nice - j_cdbs->prev_cpu_nice, 
NSEC_PER_USEC);
-                       j_cdbs->prev_cpu_nice = cur_nice;
+                       kcpustat_cputime(&kcpustat_cpu(j), j, &user, &nice, 
&sys,
+                                        &guest, &guest_nice);
+
+                       idle_time += div_u64(nice - j_cdbs->prev_cpu_nice, 
NSEC_PER_USEC);
+                       j_cdbs->prev_cpu_nice = nice;
                }
 
                if (unlikely(!time_elapsed)) {
@@ -530,8 +538,13 @@ int cpufreq_dbs_governor_start(struct cpufreq_policy 
*policy)
                 */
                j_cdbs->prev_load = 0;
 
-               if (ignore_nice)
-                       j_cdbs->prev_cpu_nice = 
kcpustat_cpu(j).cpustat[CPUTIME_NICE];
+               if (ignore_nice) {
+                       u64 user, nice, sys, guest, guest_nice;
+
+                       kcpustat_cputime(&kcpustat_cpu(j), j, &user, &nice, 
&sys,
+                                        &guest, &guest_nice);
+                       j_cdbs->prev_cpu_nice = nice;
+               }
        }
 
        gov->start(policy);
-- 
2.7.4

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