proc: stats: Use arch_idle_time for idle and iowait times if available
authorMartin Schwidefsky <schwidefsky@de.ibm.com>
Fri, 30 Mar 2012 10:23:08 +0000 (12:23 +0200)
committerThomas Gleixner <tglx@linutronix.de>
Fri, 30 Mar 2012 13:43:33 +0000 (15:43 +0200)
commitcb85a6ed67e979c59a29b7b4e8217e755b951cf4
tree512614bafe8d0038f38c30282fcf505906ff146d
parentaa2bf9bc6414b6972b9e51903c1ce7b1f057aee2
proc: stats: Use arch_idle_time for idle and iowait times if available

Git commit a25cac5198d4ff28 "proc: Consider NO_HZ when printing idle and
iowait times" changes the code for /proc/stat to use get_cpu_idle_time_us
and get_cpu_iowait_time_us if the system is running with nohz enabled.
For architectures which define arch_idle_time (currently s390 only)
this is a change for the worse. The result of arch_idle_time is supposed
to be the exact sleep time of the target cpu and should be used instead
of the value kept by the scheduler.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120330122308.18720283@de.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
fs/proc/stat.c