From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758374AbcCVIj0 (ORCPT ); Tue, 22 Mar 2016 04:39:26 -0400 Received: from cn.fujitsu.com ([59.151.112.132]:44635 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1752726AbcCVIjS (ORCPT ); Tue, 22 Mar 2016 04:39:18 -0400 X-IronPort-AV: E=Sophos;i="5.22,518,1449504000"; d="scan'208";a="4840127" From: Zhao Lei To: , Tejun Heo , Peter Zijlstra CC: Zhao Lei Subject: [PATCH v4 3/4] cpuacct: Show possible_cpu in cpuacct Date: Tue, 22 Mar 2016 16:37:07 +0800 Message-ID: X-Mailer: git-send-email 1.8.5.1 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain X-yoursite-MailScanner-ID: E2629408D268.A5818 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: zhaolei@cn.fujitsu.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 Signed-off-by: Zhao Lei --- 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