[tip: sched/core] procfs: Use vtime aware kcpustat accessor to fetch CPUTIME_SYSTEM

[tip-bot2 for Frederic Weisbecker]

The following commit has been merged into the sched/core branch of tip:

Commit-ID:     ae37fe5c07508e1c3dcdd41c9127e5d50d31013d
Gitweb:        https://git.kernel.org/tip/ae37fe5c07508e1c3dcdd41c9127e5d50d31013d
Author:        Frederic Weisbecker <frederic@xxxxxxxxxx>
AuthorDate:    Wed, 16 Oct 2019 04:56:58 +02:00
Committer:     Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Tue, 29 Oct 2019 10:01:17 +01:00

procfs: Use vtime aware kcpustat accessor to fetch CPUTIME_SYSTEM

Now that we have a vtime safe kcpustat accessor for CPUTIME_SYSTEM, use
it to start fixing frozen kcpustat values on nohz_full CPUs.

Reported-by: Yauheni Kaliuta <yauheni.kaliuta@xxxxxxxxxx>
Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Pavel Machek <pavel@xxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Rafael J . Wysocki <rjw@xxxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Cc: Wanpeng Li <wanpengli@xxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20191016025700.31277-13-frederic@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 fs/proc/stat.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/proc/stat.c b/fs/proc/stat.c
index 80c305f..5c6bd0a 100644
--- a/fs/proc/stat.c
+++ b/fs/proc/stat.c
@@ -124,7 +124,7 @@ static int show_stat(struct seq_file *p, void *v)
 
 		user += kcs->cpustat[CPUTIME_USER];
 		nice += kcs->cpustat[CPUTIME_NICE];
-		system += kcs->cpustat[CPUTIME_SYSTEM];
+		system += kcpustat_field(kcs, CPUTIME_SYSTEM, i);
 		idle += get_idle_time(kcs, i);
 		iowait += get_iowait_time(kcs, i);
 		irq += kcs->cpustat[CPUTIME_IRQ];
@@ -162,7 +162,7 @@ static int show_stat(struct seq_file *p, void *v)
 		/* Copy values here to work around gcc-2.95.3, gcc-2.96 */
 		user = kcs->cpustat[CPUTIME_USER];
 		nice = kcs->cpustat[CPUTIME_NICE];
-		system = kcs->cpustat[CPUTIME_SYSTEM];
+		system = kcpustat_field(kcs, CPUTIME_SYSTEM, i);
 		idle = get_idle_time(kcs, i);
 		iowait = get_iowait_time(kcs, i);
 		irq = kcs->cpustat[CPUTIME_IRQ];