diff options
author | Clark Williams <williams@redhat.com> | 2011-07-30 21:55:53 -0500 |
---|---|---|
committer | Clark Williams <williams@redhat.com> | 2012-04-13 11:01:51 -0500 |
commit | d9d1b9404178e97a4cad32926041f32af3096945 (patch) | |
tree | faa4790d96599061b60725953a7bef2ebd9a6fff | |
parent | e1bec773e5e6fa5f5007b6b3350b7d11c09f502f (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 }; |