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| author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2017-03-01 09:21:10 +0100 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2017-03-01 09:59:27 +0100 |
| commit | e53051e757d6cd66741955b93581e54415e48a70 (patch) | |
| tree | efe58f81dfd08a4bdf043436ddbcedd73a562c0e | |
| parent | 3c915bdc1775acfa214195da1ffb39dabdd1a389 (diff) | |
| download | linux-e53051e757d6cd66741955b93581e54415e48a70.tar.gz linux-e53051e757d6cd66741955b93581e54415e48a70.tar.bz2 linux-e53051e757d6cd66741955b93581e54415e48a70.zip | |
s390/cputime: provide archicture specific cputime_to_nsecs
The generic cputime_to_nsecs function first converts the cputime
to micro-seconds and then multiplies the result with 1000. This
looses some bits of accuracy, provide our own version of
cputime_to_nsecs that does not loose precision.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| -rw-r--r-- | arch/s390/include/asm/cputime.h | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/arch/s390/include/asm/cputime.h b/arch/s390/include/asm/cputime.h index e5672d6276a6..9072bf63a846 100644 --- a/arch/s390/include/asm/cputime.h +++ b/arch/s390/include/asm/cputime.h @@ -8,6 +8,7 @@ #define _S390_CPUTIME_H #include <linux/types.h> +#include <asm/timex.h> #define CPUTIME_PER_USEC 4096ULL #define CPUTIME_PER_SEC (CPUTIME_PER_USEC * USEC_PER_SEC) @@ -17,13 +18,18 @@ #define cmpxchg_cputime(ptr, old, new) cmpxchg64(ptr, old, new) /* - * Convert cputime to microseconds and back. + * Convert cputime to microseconds. */ static inline u64 cputime_to_usecs(const u64 cputime) { return cputime >> 12; } +/* + * Convert cputime to nanoseconds. + */ +#define cputime_to_nsecs(cputime) tod_to_ns(cputime) + u64 arch_cpu_idle_time(int cpu); #define arch_idle_time(cpu) arch_cpu_idle_time(cpu) |