powerpc/powernv/cpuidle: Init all present cpus for deep states

Init all present cpus for deep states instead of "all possible" cpus.
Init fails if a possible cpu is guarded. Resulting in making only
non-deep states available for cpuidle/hotplug.

Stewart says, this means that for single threaded workloads, if you
guard out a CPU core you'll not get WoF (Workload Optimised
Frequency), which means that performance goes down when you wouldn't
expect it to.

Fixes: 77b54e9f ("powernv/powerpc: Add winkle support for offline cpus")
Cc: stable@vger.kernel.org # v3.19+
Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/platforms/powernv/idle.c

@@ -79,7 +79,7 @@ static int pnv_save_sprs_for_deep_states(void)
 	uint64_t msr_val = MSR_IDLE;
 	uint64_t psscr_val = pnv_deepest_stop_psscr_val;
 
-	for_each_possible_cpu(cpu) {
+	for_each_present_cpu(cpu) {
 		uint64_t pir = get_hard_smp_processor_id(cpu);
 		uint64_t hsprg0_val = (uint64_t)paca_ptrs[cpu];
 
@@ -814,7 +814,7 @@ static int __init pnv_init_idle_states(void)
 		int cpu;
 
 		pr_info("powernv: idle: Saving PACA pointers of all CPUs in their thread sibling PACA\n");
-		for_each_possible_cpu(cpu) {
+		for_each_present_cpu(cpu) {
 			int base_cpu = cpu_first_thread_sibling(cpu);
 			int idx = cpu_thread_in_core(cpu);
 			int i;