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procfs: do not confuse jiffies with cputime64_t 

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>
wifi-calibration
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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1
arch/ia64/include/asm/cputime.h
View File

@ -60,6 +60,7 @@ typedef u64 cputime64_t;
*/
#define cputime_to_usecs(__ct) ((__ct) / NSEC_PER_USEC)
#define usecs_to_cputime(__usecs) ((__usecs) * NSEC_PER_USEC)
#define usecs_to_cputime64(__usecs) usecs_to_cputime(__usecs)
/*
* Convert cputime <-> seconds

2
arch/powerpc/include/asm/cputime.h
View File

@ -150,6 +150,8 @@ static inline cputime_t usecs_to_cputime(const unsigned long us)
return ct;
}
#define usecs_to_cputime64(us) usecs_to_cputime(us)
/*
* Convert cputime <-> seconds
*/

2
arch/s390/include/asm/cputime.h
View File

@ -87,6 +87,8 @@ usecs_to_cputime(const unsigned int m)
return (cputime_t) m * 4096;
}
#define usecs_to_cputime64(m) usecs_to_cputime(m)
/*
* Convert cputime to milliseconds and back.
*/

4
fs/proc/stat.c
View File

@ -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;
}

1
include/asm-generic/cputime.h
View File

@ -40,6 +40,7 @@ typedef u64 cputime64_t;
*/
#define cputime_to_usecs(__ct) jiffies_to_usecs(__ct)
#define usecs_to_cputime(__msecs) usecs_to_jiffies(__msecs)
#define usecs_to_cputime64(__msecs) nsecs_to_jiffies64((__msecs) * 1000)
/*
* Convert cputime to seconds and back.