From 26dae145a76c3615588f263885904c6e567ff116 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Thu, 21 Nov 2019 03:44:27 +0100 Subject: [PATCH] procfs: Use all-in-one vtime aware kcpustat accessor Now that we can read also user and guest time safely under vtime, use the relevant accessor to fix frozen kcpustat values on nohz_full CPUs. Reported-by: Yauheni Kaliuta Signed-off-by: Frederic Weisbecker Cc: Al Viro Cc: Peter Zijlstra Cc: Wanpeng Li Link: https://lkml.kernel.org/r/20191121024430.19938-4-frederic@kernel.org Signed-off-by: Ingo Molnar --- fs/proc/stat.c | 56 +++++++++++++++++++++++++++++++------------------------- 1 file changed, 31 insertions(+), 25 deletions(-) diff --git a/fs/proc/stat.c b/fs/proc/stat.c index 5c6bd0a..37bdbec 100644 --- a/fs/proc/stat.c +++ b/fs/proc/stat.c @@ -120,20 +120,23 @@ static int show_stat(struct seq_file *p, void *v) getboottime64(&boottime); for_each_possible_cpu(i) { - struct kernel_cpustat *kcs = &kcpustat_cpu(i); - - user += kcs->cpustat[CPUTIME_USER]; - nice += kcs->cpustat[CPUTIME_NICE]; - system += kcpustat_field(kcs, CPUTIME_SYSTEM, i); - idle += get_idle_time(kcs, i); - iowait += get_iowait_time(kcs, i); - irq += kcs->cpustat[CPUTIME_IRQ]; - softirq += kcs->cpustat[CPUTIME_SOFTIRQ]; - steal += kcs->cpustat[CPUTIME_STEAL]; - guest += kcs->cpustat[CPUTIME_GUEST]; - guest_nice += kcs->cpustat[CPUTIME_GUEST_NICE]; - sum += kstat_cpu_irqs_sum(i); - sum += arch_irq_stat_cpu(i); + struct kernel_cpustat kcpustat; + u64 *cpustat = kcpustat.cpustat; + + kcpustat_cpu_fetch(&kcpustat, i); + + user += cpustat[CPUTIME_USER]; + nice += cpustat[CPUTIME_NICE]; + system += cpustat[CPUTIME_SYSTEM]; + idle += get_idle_time(&kcpustat, i); + iowait += get_iowait_time(&kcpustat, i); + irq += cpustat[CPUTIME_IRQ]; + softirq += cpustat[CPUTIME_SOFTIRQ]; + steal += cpustat[CPUTIME_STEAL]; + guest += cpustat[CPUTIME_GUEST]; + guest_nice += cpustat[CPUTIME_USER]; + sum += kstat_cpu_irqs_sum(i); + sum += arch_irq_stat_cpu(i); for (j = 0; j < NR_SOFTIRQS; j++) { unsigned int softirq_stat = kstat_softirqs_cpu(j, i); @@ -157,19 +160,22 @@ static int show_stat(struct seq_file *p, void *v) seq_putc(p, '\n'); for_each_online_cpu(i) { - struct kernel_cpustat *kcs = &kcpustat_cpu(i); + struct kernel_cpustat kcpustat; + u64 *cpustat = kcpustat.cpustat; + + kcpustat_cpu_fetch(&kcpustat, i); /* Copy values here to work around gcc-2.95.3, gcc-2.96 */ - user = kcs->cpustat[CPUTIME_USER]; - nice = kcs->cpustat[CPUTIME_NICE]; - system = kcpustat_field(kcs, CPUTIME_SYSTEM, i); - idle = get_idle_time(kcs, i); - iowait = get_iowait_time(kcs, i); - irq = kcs->cpustat[CPUTIME_IRQ]; - softirq = kcs->cpustat[CPUTIME_SOFTIRQ]; - steal = kcs->cpustat[CPUTIME_STEAL]; - guest = kcs->cpustat[CPUTIME_GUEST]; - guest_nice = kcs->cpustat[CPUTIME_GUEST_NICE]; + user = cpustat[CPUTIME_USER]; + nice = cpustat[CPUTIME_NICE]; + system = cpustat[CPUTIME_SYSTEM]; + idle = get_idle_time(&kcpustat, i); + iowait = get_iowait_time(&kcpustat, i); + irq = cpustat[CPUTIME_IRQ]; + softirq = cpustat[CPUTIME_SOFTIRQ]; + steal = cpustat[CPUTIME_STEAL]; + guest = cpustat[CPUTIME_GUEST]; + guest_nice = cpustat[CPUTIME_USER]; seq_printf(p, "cpu%d", i); seq_put_decimal_ull(p, " ", nsec_to_clock_t(user)); seq_put_decimal_ull(p, " ", nsec_to_clock_t(nice)); -- 2.7.4