Message ID | 20140214075215.22701.23653.stgit@srivatsabhat.in.ibm.com (mailing list archive) |
---|---|
State | Changes Requested |
Delegated to: | Benjamin Herrenschmidt |
Headers | show |
On Fri, 2014-02-14 at 13:22 +0530, Srivatsa S. Bhat wrote: > 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....
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: > > 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.
diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c index 97e1dc9..d90d4b7 100644 --- a/arch/powerpc/kernel/sysfs.c +++ b/arch/powerpc/kernel/sysfs.c @@ -975,7 +975,8 @@ static int __init topology_init(void) int cpu; register_nodes(); - register_cpu_notifier(&sysfs_cpu_nb); + + cpu_notifier_register_begin(); for_each_possible_cpu(cpu) { struct cpu *c = &per_cpu(cpu_devices, cpu); @@ -999,6 +1000,11 @@ static int __init topology_init(void) if (cpu_online(cpu)) register_cpu_online(cpu); } + + __register_cpu_notifier(&sysfs_cpu_nb); + + cpu_notifier_register_done(); + #ifdef CONFIG_PPC64 sysfs_create_dscr_default(); #endif /* CONFIG_PPC64 */