Re: [PATCH v2 14/52] powerpc, sysfs: Fix CPU hotplug callback registration

Hello Ben,

On Fri, Mar 07, 2014 at 01:57:31PM +1100, Benjamin Herrenschmidt wrote:

On Fri, 2014-02-14 at 13:22 +0530, Srivatsa S. Bhat wrote:

quoted

Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:

	get_online_cpus();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	register_cpu_notifier(&foobar_cpu_notifier);

	put_online_cpus();

This patch breaks a good half of my test configs with:

/home/benh/linux-powerpc-test/arch/powerpc/kernel/sysfs.c: In function 'topology_init':
/home/benh/linux-powerpc-test/arch/powerpc/kernel/sysfs.c:979:2: error: implicit declaration of function 'cpu_notifier_register_begin' [-Werror=implicit-function-declaration]
/home/benh/linux-powerpc-test/arch/powerpc/kernel/sysfs.c:1004:2: error: implicit declaration of function '__register_cpu_notifier' [-Werror=implicit-function-declaration]
/home/benh/linux-powerpc-test/arch/powerpc/kernel/sysfs.c:1006:2: error: implicit declaration of function 'cpu_notifier_register_done' [-Werror=implicit-function-declaration]
cc1: all warnings being treated as errors
make[2]: *** [arch/powerpc/kernel/sysfs.o] Error 1
make[2]: *** Waiting for unfinished jobs....

This patch depends on
"[PATCH v2 02/52] CPU hotplug: Provide lockless versions of callback registration functions" 
of the series (Can be found here: https://lkml.org/lkml/2014/2/14/59).
This particular patch defines 'cpu_notifier_register_begin',
'__register_cpu_notifier', and 'cpu_notifier_register_done' in the
cpu-hotplug core. Are you seeing the build breakage with this patch on
?

--
Thanks and Regards
gautham.