Use the atomic64_* accessors for all the kernel_cpustat fields to
ensure atomic access on non-64 bit platforms.

Thanks to Mats Liljegren for CGROUP_CPUACCT related fixes.

Cc: Mats Liljegren <mats.liljeg...@enea.com>
Signed-off-by: Kevin Hilman <khil...@linaro.org>
---
 fs/proc/stat.c              | 40 ++++++++++++++++++++--------------------
 fs/proc/uptime.c            |  2 +-
 include/linux/kernel_stat.h |  2 +-
 kernel/sched/core.c         | 10 +++++-----
 kernel/sched/cputime.c      | 38 +++++++++++++++++++-------------------
 5 files changed, 46 insertions(+), 46 deletions(-)

diff --git a/fs/proc/stat.c b/fs/proc/stat.c
index e296572..93f7f30 100644
--- a/fs/proc/stat.c
+++ b/fs/proc/stat.c
@@ -25,7 +25,7 @@ static cputime64_t get_idle_time(int cpu)
 {
        cputime64_t idle;
 
-       idle = kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE];
+       idle = atomic64_read(&kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE]);
        if (cpu_online(cpu) && !nr_iowait_cpu(cpu))
                idle += arch_idle_time(cpu);
        return idle;
@@ -35,7 +35,7 @@ static cputime64_t get_iowait_time(int cpu)
 {
        cputime64_t iowait;
 
-       iowait = kcpustat_cpu(cpu).cpustat[CPUTIME_IOWAIT];
+       iowait = atomic64_read(&kcpustat_cpu(cpu).cpustat[CPUTIME_IOWAIT]);
        if (cpu_online(cpu) && nr_iowait_cpu(cpu))
                iowait += arch_idle_time(cpu);
        return iowait;
@@ -52,7 +52,7 @@ static u64 get_idle_time(int cpu)
 
        if (idle_time == -1ULL)
                /* !NO_HZ or cpu offline so we can rely on cpustat.idle */
-               idle = kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE];
+               idle = atomic64_read(&kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE]);
        else
                idle = usecs_to_cputime64(idle_time);
 
@@ -68,7 +68,7 @@ static u64 get_iowait_time(int cpu)
 
        if (iowait_time == -1ULL)
                /* !NO_HZ or cpu offline so we can rely on cpustat.iowait */
-               iowait = kcpustat_cpu(cpu).cpustat[CPUTIME_IOWAIT];
+               iowait = 
atomic64_read(&kcpustat_cpu(cpu).cpustat[CPUTIME_IOWAIT]);
        else
                iowait = usecs_to_cputime64(iowait_time);
 
@@ -95,16 +95,16 @@ static int show_stat(struct seq_file *p, void *v)
        jif = boottime.tv_sec;
 
        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];
+               user += atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_USER]);
+               nice += atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_NICE]);
+               system += 
atomic64_read(&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];
+               irq += atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_IRQ]);
+               softirq += 
atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_SOFTIRQ]);
+               steal += atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_STEAL]);
+               guest += atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_GUEST]);
+               guest_nice += 
atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_GUEST_NICE]);
                sum += kstat_cpu_irqs_sum(i);
                sum += arch_irq_stat_cpu(i);
 
@@ -132,16 +132,16 @@ static int show_stat(struct seq_file *p, void *v)
 
        for_each_online_cpu(i) {
                /* 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];
+               user = atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_USER]);
+               nice = atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_NICE]);
+               system = 
atomic64_read(&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];
+               irq = atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_IRQ]);
+               softirq = 
atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_SOFTIRQ]);
+               steal = atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_STEAL]);
+               guest = atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_GUEST]);
+               guest_nice = 
atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_GUEST_NICE]);
                seq_printf(p, "cpu%d", i);
                seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(user));
                seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(nice));
diff --git a/fs/proc/uptime.c b/fs/proc/uptime.c
index 9610ac7..10c0f6e 100644
--- a/fs/proc/uptime.c
+++ b/fs/proc/uptime.c
@@ -18,7 +18,7 @@ static int uptime_proc_show(struct seq_file *m, void *v)
 
        idletime = 0;
        for_each_possible_cpu(i)
-               idletime += (__force u64) kcpustat_cpu(i).cpustat[CPUTIME_IDLE];
+               idletime += 
atomic64_read(&kcpustat_cpu(i).cpustat[CPUTIME_IDLE]);
 
        do_posix_clock_monotonic_gettime(&uptime);
        monotonic_to_bootbased(&uptime);
diff --git a/include/linux/kernel_stat.h b/include/linux/kernel_stat.h
index ed5f6ed..45b9f71 100644
--- a/include/linux/kernel_stat.h
+++ b/include/linux/kernel_stat.h
@@ -32,7 +32,7 @@ enum cpu_usage_stat {
 };
 
 struct kernel_cpustat {
-       u64 cpustat[NR_STATS];
+       atomic64_t cpustat[NR_STATS];
 };
 
 struct kernel_stat {
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 2fad439..5415e85 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -8168,8 +8168,8 @@ static int cpuacct_stats_show(struct cgroup *cgrp, struct 
cftype *cft,
 
        for_each_online_cpu(cpu) {
                struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
-               val += kcpustat->cpustat[CPUTIME_USER];
-               val += kcpustat->cpustat[CPUTIME_NICE];
+               val += atomic64_read(&kcpustat->cpustat[CPUTIME_USER]);
+               val += atomic64_read(&kcpustat->cpustat[CPUTIME_NICE]);
        }
        val = cputime64_to_clock_t(val);
        cb->fill(cb, cpuacct_stat_desc[CPUACCT_STAT_USER], val);
@@ -8177,9 +8177,9 @@ static int cpuacct_stats_show(struct cgroup *cgrp, struct 
cftype *cft,
        val = 0;
        for_each_online_cpu(cpu) {
                struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
-               val += kcpustat->cpustat[CPUTIME_SYSTEM];
-               val += kcpustat->cpustat[CPUTIME_IRQ];
-               val += kcpustat->cpustat[CPUTIME_SOFTIRQ];
+               val += atomic64_read(&kcpustat->cpustat[CPUTIME_SYSTEM]);
+               val += atomic64_read(&kcpustat->cpustat[CPUTIME_IRQ]);
+               val += atomic64_read(&kcpustat->cpustat[CPUTIME_SOFTIRQ]);
        }
 
        val = cputime64_to_clock_t(val);
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index ccff275..4c639ee 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -78,14 +78,14 @@ EXPORT_SYMBOL_GPL(irqtime_account_irq);
 
 static int irqtime_account_hi_update(void)
 {
-       u64 *cpustat = kcpustat_this_cpu->cpustat;
+       atomic64_t *cpustat = kcpustat_this_cpu->cpustat;
        unsigned long flags;
        u64 latest_ns;
        int ret = 0;
 
        local_irq_save(flags);
        latest_ns = this_cpu_read(cpu_hardirq_time);
-       if (nsecs_to_cputime64(latest_ns) > cpustat[CPUTIME_IRQ])
+       if (nsecs_to_cputime64(latest_ns) > 
atomic64_read(&cpustat[CPUTIME_IRQ]));
                ret = 1;
        local_irq_restore(flags);
        return ret;
@@ -93,14 +93,14 @@ static int irqtime_account_hi_update(void)
 
 static int irqtime_account_si_update(void)
 {
-       u64 *cpustat = kcpustat_this_cpu->cpustat;
+       atomic64_t *cpustat = kcpustat_this_cpu->cpustat;
        unsigned long flags;
        u64 latest_ns;
        int ret = 0;
 
        local_irq_save(flags);
        latest_ns = this_cpu_read(cpu_softirq_time);
-       if (nsecs_to_cputime64(latest_ns) > cpustat[CPUTIME_SOFTIRQ])
+       if (nsecs_to_cputime64(latest_ns) > 
atomic64_read(&cpustat[CPUTIME_SOFTIRQ]))
                ret = 1;
        local_irq_restore(flags);
        return ret;
@@ -125,7 +125,7 @@ static inline void task_group_account_field(struct 
task_struct *p, int index,
         * is the only cgroup, then nothing else should be necessary.
         *
         */
-       __get_cpu_var(kernel_cpustat).cpustat[index] += tmp;
+       atomic64_add(tmp, &__get_cpu_var(kernel_cpustat).cpustat[index]);
 
 #ifdef CONFIG_CGROUP_CPUACCT
        if (unlikely(!cpuacct_subsys.active))
@@ -135,7 +135,7 @@ static inline void task_group_account_field(struct 
task_struct *p, int index,
        ca = task_ca(p);
        while (ca && (ca != &root_cpuacct)) {
                kcpustat = this_cpu_ptr(ca->cpustat);
-               kcpustat->cpustat[index] += tmp;
+               atomic64_add(tmp, &kcpustat->cpustat[index]);
                ca = parent_ca(ca);
        }
        rcu_read_unlock();
@@ -176,7 +176,7 @@ void account_user_time(struct task_struct *p, cputime_t 
cputime,
 static void account_guest_time(struct task_struct *p, cputime_t cputime,
                               cputime_t cputime_scaled)
 {
-       u64 *cpustat = kcpustat_this_cpu->cpustat;
+       atomic64_t *cpustat = kcpustat_this_cpu->cpustat;
 
        /* Add guest time to process. */
        p->utime += cputime;
@@ -186,11 +186,11 @@ static void account_guest_time(struct task_struct *p, 
cputime_t cputime,
 
        /* Add guest time to cpustat. */
        if (TASK_NICE(p) > 0) {
-               cpustat[CPUTIME_NICE] += (__force u64) cputime;
-               cpustat[CPUTIME_GUEST_NICE] += (__force u64) cputime;
+               atomic64_add((__force u64) cputime, &cpustat[CPUTIME_NICE]);
+               atomic64_add((__force u64) cputime, 
&cpustat[CPUTIME_GUEST_NICE]);
        } else {
-               cpustat[CPUTIME_USER] += (__force u64) cputime;
-               cpustat[CPUTIME_GUEST] += (__force u64) cputime;
+               atomic64_add((__force u64) cputime, &cpustat[CPUTIME_USER]);
+               atomic64_add((__force u64) cputime, &cpustat[CPUTIME_GUEST]);
        }
 }
 
@@ -250,9 +250,9 @@ void account_system_time(struct task_struct *p, int 
hardirq_offset,
  */
 void account_steal_time(cputime_t cputime)
 {
-       u64 *cpustat = kcpustat_this_cpu->cpustat;
+       atomic64_t *cpustat = kcpustat_this_cpu->cpustat;
 
-       cpustat[CPUTIME_STEAL] += (__force u64) cputime;
+       atomic64_add((__force u64) cputime, &cpustat[CPUTIME_STEAL]);
 }
 
 /*
@@ -261,13 +261,13 @@ void account_steal_time(cputime_t cputime)
  */
 void account_idle_time(cputime_t cputime)
 {
-       u64 *cpustat = kcpustat_this_cpu->cpustat;
+       atomic64_t *cpustat = kcpustat_this_cpu->cpustat;
        struct rq *rq = this_rq();
 
        if (atomic_read(&rq->nr_iowait) > 0)
-               cpustat[CPUTIME_IOWAIT] += (__force u64) cputime;
+               atomic64_add((__force u64) cputime, &cpustat[CPUTIME_IOWAIT]);
        else
-               cpustat[CPUTIME_IDLE] += (__force u64) cputime;
+               atomic64_add((__force u64) cputime, &cpustat[CPUTIME_IDLE]);
 }
 
 static __always_inline bool steal_account_process_tick(void)
@@ -345,15 +345,15 @@ static void irqtime_account_process_tick(struct 
task_struct *p, int user_tick,
                                                struct rq *rq)
 {
        cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy);
-       u64 *cpustat = kcpustat_this_cpu->cpustat;
+       atomic64_t *cpustat = kcpustat_this_cpu->cpustat;
 
        if (steal_account_process_tick())
                return;
 
        if (irqtime_account_hi_update()) {
-               cpustat[CPUTIME_IRQ] += (__force u64) cputime_one_jiffy;
+               atomic64_add((__force u64) cputime_one_jiffy, 
&cpustat[CPUTIME_IRQ]);
        } else if (irqtime_account_si_update()) {
-               cpustat[CPUTIME_SOFTIRQ] += (__force u64) cputime_one_jiffy;
+               atomic64_add((__force u64) cputime_one_jiffy, 
&cpustat[CPUTIME_SOFTIRQ]);
        } else if (this_cpu_ksoftirqd() == p) {
                /*
                 * ksoftirqd time do not get accounted in cpu_softirq_time.
-- 
1.8.1.2


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