Current code show stats of online cpus in cpuacct.statcpus,
show stats of present cpus in cpuacct.usage(_percpu), and using
present cpus for setting cpuacct.usage.
It will cause inconsistent result when a cpu is online or offline
or hotpluged.
We should always use possible cpus to avoid above problem.
Content of cpuacct.usage_percpu changed after this patch:
(On a 4 cpu system with maxcpus=32)
Before patch:
# cat cpuacct.usage_percpu
2456565 411435 1052897 832584
After patch:
# cat cpuacct.usage_percpu
2456565 411435 1052897 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Suggested-by: Peter Zijlstra <pet...@infradead.org>
Signed-off-by: Zhao Lei <zhao...@cn.fujitsu.com>
---
kernel/sched/cpuacct.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c
index 434c2fa..4399850 100644
--- a/kernel/sched/cpuacct.c
+++ b/kernel/sched/cpuacct.c
@@ -138,7 +138,7 @@ static u64 cpuusage_read(struct cgroup_subsys_state *css,
struct cftype *cft)
u64 totalcpuusage = 0;
int i;
- for_each_present_cpu(i)
+ for_each_possible_cpu(i)
totalcpuusage += cpuacct_cpuusage_read(ca, i);
return totalcpuusage;
@@ -159,7 +159,7 @@ static int cpuusage_write(struct cgroup_subsys_state *css,
struct cftype *cft,
goto out;
}
- for_each_present_cpu(i)
+ for_each_possible_cpu(i)
cpuacct_cpuusage_write(ca, i, 0);
out:
@@ -172,7 +172,7 @@ static int cpuacct_percpu_seq_show(struct seq_file *m, void
*V)
u64 percpu;
int i;
- for_each_present_cpu(i) {
+ for_each_possible_cpu(i) {
percpu = cpuacct_cpuusage_read(ca, i);
seq_printf(m, "%llu ", (unsigned long long) percpu);
}
@@ -191,7 +191,7 @@ static int cpuacct_stats_show(struct seq_file *sf, void *v)
int cpu;
s64 val = 0;
- for_each_online_cpu(cpu) {
+ for_each_possible_cpu(cpu) {
struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
val += kcpustat->cpustat[CPUTIME_USER];
val += kcpustat->cpustat[CPUTIME_NICE];
@@ -200,7 +200,7 @@ static int cpuacct_stats_show(struct seq_file *sf, void *v)
seq_printf(sf, "%s %lld\n", cpuacct_stat_desc[CPUACCT_STAT_USER], val);
val = 0;
- for_each_online_cpu(cpu) {
+ for_each_possible_cpu(cpu) {
struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
val += kcpustat->cpustat[CPUTIME_SYSTEM];
val += kcpustat->cpustat[CPUTIME_IRQ];
--
1.8.5.1
