From 2987557f52b97f679f0c324d8f51b8d66e1f2084 Mon Sep 17 00:00:00 2001 From: Josh Triplett Date: Sat, 3 Dec 2011 13:06:50 -0800 Subject: driver-core/cpu: Expose hotpluggability to the rest of the kernel When architectures register CPUs, they indicate whether the CPU allows hotplugging; notably, x86 and ARM don't allow hotplugging CPU 0. Userspace can easily query the hotpluggability of a CPU via sysfs; however, the kernel has no convenient way of accessing that property in an architecture-independent way. While the kernel can simply try it and see, some code needs to distinguish between "hotplug failed" and "hotplug has no hope of working on this CPU"; for example, rcutorture's CPU hotplug tests want to avoid drowning out real hotplug failures with expected failures. Expose this property via a new cpu_is_hotpluggable function, so that the rest of the kernel can access it in an architecture-independent way. Signed-off-by: Josh Triplett Signed-off-by: Paul E. McKenney --- include/linux/cpu.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/cpu.h b/include/linux/cpu.h index 6cb60fd2ea84..305c263021e7 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -27,6 +27,7 @@ struct cpu { extern int register_cpu(struct cpu *cpu, int num); extern struct sys_device *get_cpu_sysdev(unsigned cpu); +extern bool cpu_is_hotpluggable(unsigned cpu); extern int cpu_add_sysdev_attr(struct sysdev_attribute *attr); extern void cpu_remove_sysdev_attr(struct sysdev_attribute *attr); -- cgit v1.2.3