KVM: Convert kvm_lock to raw_spinlock

Code under this lock requires non-preemptibility. Ensure this also over
-rt by converting it to raw spinlock.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index ffd7f8d2918749a8f0a7f6cc4d6467c2fc139e25..a58aebef5188557105062918eb849181da7f58fd 100644 (file)
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -85,7 +85,7 @@
 
 #define ASYNC_PF_PER_VCPU 64
 
-extern spinlock_t kvm_lock;
+extern raw_spinlock_t kvm_lock;
 extern struct list_head vm_list;
 
 struct kvm_vcpu;

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index ccacf0b1b540e7098a391e297e2905df487490b9..b6a9963400a7416db07e13c285c005f8cc4d6a2b 100644 (file)
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -3587,7 +3587,7 @@ static int mmu_shrink(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
        if (nr_to_scan == 0)
                goto out;
 
-       spin_lock(&kvm_lock);
+       raw_spin_lock(&kvm_lock);
 
        list_for_each_entry(kvm, &vm_list, vm_list) {
                int idx, freed_pages;
@@ -3610,7 +3610,7 @@ static int mmu_shrink(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
        if (kvm_freed)
                list_move_tail(&kvm_freed->vm_list, &vm_list);
 
-       spin_unlock(&kvm_lock);
+       raw_spin_unlock(&kvm_lock);
 
 out:
        return percpu_counter_read_positive(&kvm_total_used_mmu_pages);

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index bd59e8ede88e0ba1d7c82ce1bcc252bf3068602a..d9855b8584cfcdc37835c2358948848333190c73 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4557,7 +4557,7 @@ static int kvmclock_cpufreq_notifier(struct notifier_block *nb, unsigned long va
 
        smp_call_function_single(freq->cpu, tsc_khz_changed, freq, 1);
 
-       spin_lock(&kvm_lock);
+       raw_spin_lock(&kvm_lock);
        list_for_each_entry(kvm, &vm_list, vm_list) {
                kvm_for_each_vcpu(i, vcpu, kvm) {
                        if (vcpu->cpu != freq->cpu)
@@ -4567,7 +4567,7 @@ static int kvmclock_cpufreq_notifier(struct notifier_block *nb, unsigned long va
                                send_ipi = 1;
                }
        }
-       spin_unlock(&kvm_lock);
+       raw_spin_unlock(&kvm_lock);
 
        if (freq->old < freq->new && send_ipi) {
                /*

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 2dc53a6dc2853098fcf222f0a9a59bed34d264b9..1fa0d292119a4681ad8c691d3dcfbd94e7cb37a4 100644 (file)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -69,7 +69,7 @@ MODULE_LICENSE("GPL");
  *             kvm->lock --> kvm->slots_lock --> kvm->irq_lock
  */
 
-DEFINE_SPINLOCK(kvm_lock);
+DEFINE_RAW_SPINLOCK(kvm_lock);
 LIST_HEAD(vm_list);
 
 static cpumask_var_t cpus_hardware_enabled;
@@ -481,9 +481,9 @@ static struct kvm *kvm_create_vm(void)
        mutex_init(&kvm->irq_lock);
        mutex_init(&kvm->slots_lock);
        atomic_set(&kvm->users_count, 1);
-       spin_lock(&kvm_lock);
+       raw_spin_lock(&kvm_lock);
        list_add(&kvm->vm_list, &vm_list);
-       spin_unlock(&kvm_lock);
+       raw_spin_unlock(&kvm_lock);
 
        return kvm;
 
@@ -556,9 +556,9 @@ static void kvm_destroy_vm(struct kvm *kvm)
        struct mm_struct *mm = kvm->mm;
 
        kvm_arch_sync_events(kvm);
-       spin_lock(&kvm_lock);
+       raw_spin_lock(&kvm_lock);
        list_del(&kvm->vm_list);
-       spin_unlock(&kvm_lock);
+       raw_spin_unlock(&kvm_lock);
        kvm_free_irq_routing(kvm);
        for (i = 0; i < KVM_NR_BUSES; i++)
                kvm_io_bus_destroy(kvm->buses[i]);
@@ -2177,9 +2177,9 @@ static void hardware_enable_nolock(void *junk)
 
 static void hardware_enable(void *junk)
 {
-       spin_lock(&kvm_lock);
+       raw_spin_lock(&kvm_lock);
        hardware_enable_nolock(junk);
-       spin_unlock(&kvm_lock);
+       raw_spin_unlock(&kvm_lock);
 }
 
 static void hardware_disable_nolock(void *junk)
@@ -2194,9 +2194,9 @@ static void hardware_disable_nolock(void *junk)
 
 static void hardware_disable(void *junk)
 {
-       spin_lock(&kvm_lock);
+       raw_spin_lock(&kvm_lock);
        hardware_disable_nolock(junk);
-       spin_unlock(&kvm_lock);
+       raw_spin_unlock(&kvm_lock);
 }
 
 static void hardware_disable_all_nolock(void)
@@ -2210,16 +2210,16 @@ static void hardware_disable_all_nolock(void)
 
 static void hardware_disable_all(void)
 {
-       spin_lock(&kvm_lock);
+       raw_spin_lock(&kvm_lock);
        hardware_disable_all_nolock();
-       spin_unlock(&kvm_lock);
+       raw_spin_unlock(&kvm_lock);
 }
 
 static int hardware_enable_all(void)
 {
        int r = 0;
 
-       spin_lock(&kvm_lock);
+       raw_spin_lock(&kvm_lock);
 
        kvm_usage_count++;
        if (kvm_usage_count == 1) {
@@ -2232,7 +2232,7 @@ static int hardware_enable_all(void)
                }
        }
 
-       spin_unlock(&kvm_lock);
+       raw_spin_unlock(&kvm_lock);
 
        return r;
 }
@@ -2394,10 +2394,10 @@ static int vm_stat_get(void *_offset, u64 *val)
        struct kvm *kvm;
 
        *val = 0;
-       spin_lock(&kvm_lock);
+       raw_spin_lock(&kvm_lock);
        list_for_each_entry(kvm, &vm_list, vm_list)
                *val += *(u32 *)((void *)kvm + offset);
-       spin_unlock(&kvm_lock);
+       raw_spin_unlock(&kvm_lock);
        return 0;
 }
 
@@ -2411,12 +2411,12 @@ static int vcpu_stat_get(void *_offset, u64 *val)
        int i;
 
        *val = 0;
-       spin_lock(&kvm_lock);
+       raw_spin_lock(&kvm_lock);
        list_for_each_entry(kvm, &vm_list, vm_list)
                kvm_for_each_vcpu(i, vcpu, kvm)
                        *val += *(u32 *)((void *)vcpu + offset);
 
-       spin_unlock(&kvm_lock);
+       raw_spin_unlock(&kvm_lock);
        return 0;
 }
 
@@ -2457,7 +2457,7 @@ static int kvm_suspend(struct sys_device *dev, pm_message_t state)
 static int kvm_resume(struct sys_device *dev)
 {
        if (kvm_usage_count) {
-               WARN_ON(spin_is_locked(&kvm_lock));
+               WARN_ON(raw_spin_is_locked(&kvm_lock));
                hardware_enable_nolock(NULL);
        }
        return 0;