KVM: x86: avoid useless copy of cpufreq policy

struct cpufreq_policy is quite big and it is not a good idea
to allocate one on the stack.  Just use cpufreq_cpu_get and
cpufreq_cpu_put which is even simpler.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 359fcd3..bcb6b67 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7190,15 +7190,15 @@ static void kvm_timer_init(void)
 
        if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
 #ifdef CONFIG_CPU_FREQ
-               struct cpufreq_policy policy;
+               struct cpufreq_policy *policy;
                int cpu;
 
-               memset(&policy, 0, sizeof(policy));
                cpu = get_cpu();
-               cpufreq_get_policy(&policy, cpu);
-               if (policy.cpuinfo.max_freq)
-                       max_tsc_khz = policy.cpuinfo.max_freq;
+               policy = cpufreq_cpu_get(cpu);
+               if (policy && policy->cpuinfo.max_freq)
+                       max_tsc_khz = policy->cpuinfo.max_freq;
                put_cpu();
+               cpufreq_cpu_put(policy);
 #endif
                cpufreq_register_notifier(&kvmclock_cpufreq_notifier_block,
                                          CPUFREQ_TRANSITION_NOTIFIER);