diff options
| author | Clark Williams <williams@redhat.com> | 2011-07-31 02:55:53 (GMT) |
|---|---|---|
| committer | Scott Wood <scottwood@freescale.com> | 2015-02-13 22:20:59 (GMT) |
| commit | d1b60e49575ff571df99e87c04ea21c60cbc7c4a (patch) | |
| tree | 1438098e11c1fc22a445eae7cf613dc85dd07480 /kernel | |
| parent | 8d627274e496041f381a09ef1c0fa166ae3693d9 (diff) | |
| download | linux-fsl-qoriq-d1b60e49575ff571df99e87c04ea21c60cbc7c4a.tar.xz | |
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>
Diffstat (limited to 'kernel')
| -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 9659d38..b66ab9e 100644 --- a/kernel/ksysfs.c +++ b/kernel/ksysfs.c @@ -132,6 +132,15 @@ 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) @@ -197,6 +206,9 @@ static struct attribute * kernel_attrs[] = { &vmcoreinfo_attr.attr, #endif &rcu_expedited_attr.attr, +#ifdef CONFIG_PREEMPT_RT_FULL + &realtime_attr.attr, +#endif NULL }; |