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procfs: do not confuse jiffies with cputime64_t

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Commit 2a95ea6c0d ("procfs: do not overflow get_{idle,iowait}_time
for nohz") did not take into account that one some architectures jiffies
and cputime use different units.

This causes get_idle_time() to return numbers in the wrong units, making
the idle time fields in /proc/stat wrong.

Instead of converting the usec value returned by
get_cpu_{idle,iowait}_time_us to units of jiffies, use the new function
usecs_to_cputime64 to convert it to the correct unit of cputime64_t.

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Artem S. Tashkinov" <t.artem@mailcity.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Andreas Schwab
2011-12-28 15:57:15 -08:00
committed by Linus Torvalds
parent e26a51148f
commit 34845636a1
5 changed files with 8 additions and 2 deletions
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4
fs/proc/stat.c
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@ -32,7 +32,7 @@ static cputime64_t get_idle_time(int cpu)
idle = kstat_cpu(cpu).cpustat.idle;
idle = cputime64_add(idle, arch_idle_time(cpu));
} else
idle = nsecs_to_jiffies64(1000 * idle_time);
idle = usecs_to_cputime64(idle_time);
return idle;
}
@ -46,7 +46,7 @@ static cputime64_t get_iowait_time(int cpu)
/* !NO_HZ so we can rely on cpustat.iowait */
iowait = kstat_cpu(cpu).cpustat.iowait;
else
iowait = nsecs_to_jiffies64(1000 * iowait_time);
iowait = usecs_to_cputime64(iowait_time);
return iowait;
}