From 5720821ba1d845f0b91a9278137e9005c5f6931d Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Thu, 21 Nov 2019 03:44:28 +0100 Subject: [PATCH] cpufreq: Use vtime aware kcpustat accessors for user time We can now safely read user and guest kcpustat fields on nohz_full CPUs. Use the appropriate accessors. Reported-by: Yauheni Kaliuta Signed-off-by: Frederic Weisbecker Cc: Rafael J. Wysocki Cc: Viresh Kumar Cc: Peter Zijlstra Cc: Wanpeng Li Link: https://lkml.kernel.org/r/20191121024430.19938-5-frederic@kernel.org Signed-off-by: Ingo Molnar --- drivers/cpufreq/cpufreq.c | 17 ++++++++++------- drivers/cpufreq/cpufreq_governor.c | 6 +++--- 2 files changed, 13 insertions(+), 10 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 527fd068dc12..ee23eaf20f35 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -113,18 +113,21 @@ EXPORT_SYMBOL_GPL(get_governor_parent_kobj); static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) { - u64 idle_time; + struct kernel_cpustat kcpustat; u64 cur_wall_time; + u64 idle_time; u64 busy_time; cur_wall_time = jiffies64_to_nsecs(get_jiffies_64()); - busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; - busy_time += kcpustat_field(&kcpustat_cpu(cpu), CPUTIME_SYSTEM, cpu); - busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; - busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; - busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; - busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; + kcpustat_cpu_fetch(&kcpustat, cpu); + + busy_time = kcpustat.cpustat[CPUTIME_USER]; + busy_time += kcpustat.cpustat[CPUTIME_SYSTEM]; + busy_time += kcpustat.cpustat[CPUTIME_IRQ]; + busy_time += kcpustat.cpustat[CPUTIME_SOFTIRQ]; + busy_time += kcpustat.cpustat[CPUTIME_STEAL]; + busy_time += kcpustat.cpustat[CPUTIME_NICE]; idle_time = cur_wall_time - busy_time; if (wall) diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c index 4bb054d0cb43..f99ae45efaea 100644 --- a/drivers/cpufreq/cpufreq_governor.c +++ b/drivers/cpufreq/cpufreq_governor.c @@ -105,7 +105,7 @@ void gov_update_cpu_data(struct dbs_data *dbs_data) j_cdbs->prev_cpu_idle = get_cpu_idle_time(j, &j_cdbs->prev_update_time, dbs_data->io_is_busy); if (dbs_data->ignore_nice_load) - j_cdbs->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE]; + j_cdbs->prev_cpu_nice = kcpustat_field(&kcpustat_cpu(j), CPUTIME_NICE, j); } } } @@ -149,7 +149,7 @@ unsigned int dbs_update(struct cpufreq_policy *policy) j_cdbs->prev_cpu_idle = cur_idle_time; if (ignore_nice) { - u64 cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE]; + u64 cur_nice = kcpustat_field(&kcpustat_cpu(j), CPUTIME_NICE, j); idle_time += div_u64(cur_nice - j_cdbs->prev_cpu_nice, NSEC_PER_USEC); j_cdbs->prev_cpu_nice = cur_nice; @@ -530,7 +530,7 @@ int cpufreq_dbs_governor_start(struct cpufreq_policy *policy) j_cdbs->prev_load = 0; if (ignore_nice) - j_cdbs->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE]; + j_cdbs->prev_cpu_nice = kcpustat_field(&kcpustat_cpu(j), CPUTIME_NICE, j); } gov->start(policy); -- 2.30.2