diff options
| author | Clark Williams <williams@redhat.com> | 2011-07-30 21:55:53 -0500 |
|---|---|---|
| committer | Clark Williams <williams@redhat.com> | 2011-11-14 11:02:09 -0600 |
| commit | ccc0503c7ef9d7f06bd46c2dc4b936350e2a2e89 (patch) | |
| tree | c93667223b4a500cc7447febc5363cb16af2363b | |
| parent | cfd47becaf308f6742d2b9d162612e98f2cab4eb (diff) | |
add /sys/kernel/realtime entry
Add a /sys/kernel entry to indicate that the kernel is a
realtime kernel.
Clark says that he needs this for udev rules, udev needs to evaluate
if its a PREEMPT_RT kernel a few thousand times and parsing uname
output is too slow or so.
Are there better solutions? Should it exist and return 0 on !-rt?
Signed-off-by: Clark Williams <williams@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
| -rw-r--r-- | kernel/ksysfs.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c index 4e316e1acf58..a546d3303a2c 100644 --- a/kernel/ksysfs.c +++ b/kernel/ksysfs.c @@ -133,6 +133,15 @@ KERNEL_ATTR_RO(vmcoreinfo); #endif /* CONFIG_KEXEC */ +#if defined(CONFIG_PREEMPT_RT_FULL) +static ssize_t realtime_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", 1); +} +KERNEL_ATTR_RO(realtime); +#endif + /* whether file capabilities are enabled */ static ssize_t fscaps_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) @@ -182,6 +191,9 @@ static struct attribute * kernel_attrs[] = { &kexec_crash_size_attr.attr, &vmcoreinfo_attr.attr, #endif +#ifdef CONFIG_PREEMPT_RT_FULL + &realtime_attr.attr, +#endif NULL }; |