On 30 January 2015 at 09:16, ethan zhao <ethan.zhao@xxxxxxxxxx> wrote: > You mean the policy is shared by all CPUs, so PPC notification about one A policy may or maynot be shared by multiple CPUs. It all depends on your systems configuration. All CPUs which share clock line, share a policy. You can verify that from /sys/devices/system/cpu/cpu*/related_cpus. This gives the CPUs that share policy. > CPU should update all CPU's policy, right ? even the requested CPU is > shutting down. CPUs sharing policy have a single policy structure. And so policy would be updated for all CPUs that share the poilcy. Even if some cpu goes down, the policy might still be up and running. -- viresh -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html