diff options
author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2009-04-23 13:58:08 +0200 |
---|---|---|
committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2009-04-23 13:58:17 +0200 |
commit | e1c805309d19c69d4ebeac38724076fa86feacdf (patch) | |
tree | 73886783aac7c489a29f3e5eec56cbc2371a12dd /arch | |
parent | b1ad171efa089ae26aba750d747d8149a4f860d5 (diff) | |
download | op-kernel-dev-e1c805309d19c69d4ebeac38724076fa86feacdf.zip op-kernel-dev-e1c805309d19c69d4ebeac38724076fa86feacdf.tar.gz |
[S390] /proc/stat idle field for idle cpus
The cpu idle field in the output of /proc/stat is too small for cpus
that have been idle for more than a tick. Add the architecture hook
arch_idle_time that allows to add the not accounted idle time of a
sleeping cpu without waking the cpu.
The s390 implementation of arch_idle_time uses the already existing
s390_idle_data per_cpu variable to find the sleep time of a neighboring
idle cpu.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/s390/include/asm/cputime.h | 4 | ||||
-rw-r--r-- | arch/s390/kernel/vtime.c | 16 |
2 files changed, 20 insertions, 0 deletions
diff --git a/arch/s390/include/asm/cputime.h b/arch/s390/include/asm/cputime.h index 95b0f7d..941384f 100644 --- a/arch/s390/include/asm/cputime.h +++ b/arch/s390/include/asm/cputime.h @@ -174,4 +174,8 @@ cputime64_to_clock_t(cputime64_t cputime) return __div(cputime, 4096000000ULL / USER_HZ); } +cputime64_t s390_get_idle_time(int cpu); + +#define arch_idle_time(cpu) s390_get_idle_time(cpu) + #endif /* _S390_CPUTIME_H */ diff --git a/arch/s390/kernel/vtime.c b/arch/s390/kernel/vtime.c index 38ea92f..c87f59b 100644 --- a/arch/s390/kernel/vtime.c +++ b/arch/s390/kernel/vtime.c @@ -240,6 +240,22 @@ void vtime_stop_cpu(void) } } +cputime64_t s390_get_idle_time(int cpu) +{ + struct s390_idle_data *idle; + unsigned long long now, idle_time, idle_enter; + + idle = &per_cpu(s390_idle, cpu); + spin_lock(&idle->lock); + now = get_clock(); + idle_time = 0; + idle_enter = idle->idle_enter; + if (idle_enter != 0ULL && idle_enter < now) + idle_time = now - idle_enter; + spin_unlock(&idle->lock); + return idle_time; +} + /* * Sorted add to a list. List is linear searched until first bigger * element is found. |