[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>

1 files changed, 24 insertions, 27 deletions

diff --git a/arch/x86/kernel/cpu/cpufreq/speedstep-centrino.c b/arch/x86/kernel/cpu/cpufreq/speedstep-centrino.c
index 3b5f06423e77..f0ea6fa2f53c 100644
--- 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);
                 }