Commit-ID: 5ca3726af7f66a8cc71ce4414cfeb86deb784491 Gitweb: http://git.kernel.org/tip/5ca3726af7f66a8cc71ce4414cfeb86deb784491 Author: Zhao Lei <zhao...@cn.fujitsu.com> AuthorDate: Tue, 22 Mar 2016 16:37:07 +0800 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Thu, 31 Mar 2016 10:45:56 +0200
sched/cpuacct: Show all possible CPUs in cpuacct output 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. Here are the contents of a cpuacct.usage_percpu sysfs file, on a 4 CPU system with maxcpus=32: Before the patch: # cat cpuacct.usage_percpu 2456565 411435 1052897 832584 After the 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> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Mike Galbraith <efa...@gmx.de> Cc: Tejun Heo <hte...@gmail.com> Cc: Thomas Gleixner <t...@linutronix.de> Link: http://lkml.kernel.org/r/a11d56cef12d0b4807f8be3a46bf9798c3014d59.1458635566.git.zhao...@cn.fujitsu.com Signed-off-by: Ingo Molnar <mi...@kernel.org> --- 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 4a81120..e39bd4f 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];
