[CPUFREQ] clean up speedstep-centrino and reduce cpumask_t usage

Impact: cleanup

1) The #ifdef CONFIG_HOTPLUG_CPU seems unnecessary these days.
2) The loop can simply skip over offline cpus, rather than creating a tmp mask.
3) set_mask is set to either a single cpu or all online cpus in a policy.
   Since it's just used for set_cpus_allowed(), any offline cpus in a policy
   don't matter, so we can just use cpumask_of_cpu() or the policy->cpus.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Dave Jones <davej@redhat.com>

diff --git a/arch/x86/kernel/cpu/cpufreq/speedstep-centrino.c b/arch/x86/kernel/cpu/cpufreq/speedstep-centrino.c
index 3b5f06423e7774f2801e31e811c631df90344e36..f0ea6fa2f53c8a58ad1982c88c5b5869b9428c60 100644 (file)
--- a/arch/x86/kernel/cpu/cpufreq/speedstep-centrino.c
+++ b/arch/x86/kernel/cpu/cpufreq/speedstep-centrino.c
@@ -459,9 +459,7 @@ static int centrino_verify (struct cpufreq_policy *policy)
  * Sets a new CPUFreq policy.
  */
 struct allmasks {
-       cpumask_t               online_policy_cpus;
        cpumask_t               saved_mask;
-       cpumask_t               set_mask;
        cpumask_t               covered_cpus;
 };
 
@@ -475,9 +473,7 @@ static int centrino_target (struct cpufreq_policy *policy,
        int                     retval = 0;
        unsigned int            j, k, first_cpu, tmp;
        CPUMASK_ALLOC(allmasks);
-       CPUMASK_PTR(online_policy_cpus, allmasks);
        CPUMASK_PTR(saved_mask, allmasks);
-       CPUMASK_PTR(set_mask, allmasks);
        CPUMASK_PTR(covered_cpus, allmasks);
 
        if (unlikely(allmasks == NULL))
@@ -497,30 +493,28 @@ static int centrino_target (struct cpufreq_policy *policy,
                goto out;
        }
 
-#ifdef CONFIG_HOTPLUG_CPU
-       /* cpufreq holds the hotplug lock, so we are safe from here on */
-       cpus_and(*online_policy_cpus, cpu_online_map, policy->cpus);
-#else
-       *online_policy_cpus = policy->cpus;
-#endif
-
        *saved_mask = current->cpus_allowed;
        first_cpu = 1;
        cpus_clear(*covered_cpus);
-       for_each_cpu_mask_nr(j, *online_policy_cpus) {
+       for_each_cpu_mask_nr(j, policy->cpus) {
+               const cpumask_t *mask;
+
+               /* cpufreq holds the hotplug lock, so we are safe here */
+               if (!cpu_online(j))
+                       continue;
+
                /*
                 * Support for SMP systems.
                 * Make sure we are running on CPU that wants to change freq
                 */
-               cpus_clear(*set_mask);
                if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY)
-                       cpus_or(*set_mask, *set_mask, *online_policy_cpus);
+                       mask = &policy->cpus;
                else
-                       cpu_set(j, *set_mask);
+                       mask = &cpumask_of_cpu(j);
 
-               set_cpus_allowed_ptr(current, set_mask);
+               set_cpus_allowed_ptr(current, mask);
                preempt_disable();
-               if (unlikely(!cpu_isset(smp_processor_id(), *set_mask))) {
+               if (unlikely(!cpu_isset(smp_processor_id(), *mask))) {
                        dprintk("couldn't limit to CPUs in this domain\n");
                        retval = -EAGAIN;
                        if (first_cpu) {
@@ -548,7 +542,9 @@ static int centrino_target (struct cpufreq_policy *policy,
                        dprintk("target=%dkHz old=%d new=%d msr=%04x\n",
                                target_freq, freqs.old, freqs.new, msr);
 
-                       for_each_cpu_mask_nr(k, *online_policy_cpus) {
+                       for_each_cpu_mask_nr(k, policy->cpus) {
+                               if (!cpu_online(k))
+                                       continue;
                                freqs.cpu = k;
                                cpufreq_notify_transition(&freqs,
                                        CPUFREQ_PRECHANGE);
@@ -571,7 +567,9 @@ static int centrino_target (struct cpufreq_policy *policy,
                preempt_enable();
        }
 
-       for_each_cpu_mask_nr(k, *online_policy_cpus) {
+       for_each_cpu_mask_nr(k, policy->cpus) {
+               if (!cpu_online(k))
+                       continue;
                freqs.cpu = k;
                cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
        }
@@ -584,18 +582,17 @@ static int centrino_target (struct cpufreq_policy *policy,
                 * Best effort undo..
                 */
 
-               if (!cpus_empty(*covered_cpus))
-                       for_each_cpu_mask_nr(j, *covered_cpus) {
-                               set_cpus_allowed_ptr(current,
-                                                    &cpumask_of_cpu(j));
-                               wrmsr(MSR_IA32_PERF_CTL, oldmsr, h);
-                       }
+               for_each_cpu_mask_nr(j, *covered_cpus) {
+                       set_cpus_allowed_ptr(current, &cpumask_of_cpu(j));
+                       wrmsr(MSR_IA32_PERF_CTL, oldmsr, h);
+               }
 
                tmp = freqs.new;
                freqs.new = freqs.old;
                freqs.old = tmp;
-               for_each_cpu_mask_nr(j, *online_policy_cpus) {
-                       freqs.cpu = j;
+               for_each_cpu_mask_nr(j, policy->cpus) {
+                       if (!cpu_online(j))
+                               continue;
                        cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
                        cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
                }