[PATCH] KVM: Convert PIC lock from raw spinlock to ordinary spinlock

[PATCH] KVM: Convert PIC lock from raw spinlock to ordinary spinlock

[Avi Kivity]

The PIC code used to be called from preempt_disable() context, which
wasn't very good for PREEMPT_RT.  That is no longer the case, so move
back from raw_spinlock_t to spinlock_t.

Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/i8259.c |    6 +++---
 arch/x86/kvm/irq.h   |    2 +-
 arch/x86/kvm/x86.c   |    8 ++++----
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index ab1bb8f..dd54c5b 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -39,7 +39,7 @@ static void pic_irq_request(struct kvm *kvm, int level);
 static void pic_lock(struct kvm_pic *s)
 	__acquires(&s->lock)
 {
-	raw_spin_lock(&s->lock);
+	spin_lock(&s->lock);
 }
 
 static void pic_unlock(struct kvm_pic *s)
@@ -51,7 +51,7 @@ static void pic_unlock(struct kvm_pic *s)
 
 	s->wakeup_needed = false;
 
-	raw_spin_unlock(&s->lock);
+	spin_unlock(&s->lock);
 
 	if (wakeup) {
 		kvm_for_each_vcpu(i, vcpu, s->kvm) {
@@ -569,7 +569,7 @@ struct kvm_pic *kvm_create_pic(struct kvm *kvm)
 	s = kzalloc(sizeof(struct kvm_pic), GFP_KERNEL);
 	if (!s)
 		return NULL;
-	raw_spin_lock_init(&s->lock);
+	spin_lock_init(&s->lock);
 	s->kvm = kvm;
 	s->pics[0].elcr_mask = 0xf8;
 	s->pics[1].elcr_mask = 0xde;
diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index 63c3145..ba910d1 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -60,7 +60,7 @@ struct kvm_kpic_state {
 };
 
 struct kvm_pic {
-	raw_spinlock_t lock;
+	spinlock_t lock;
 	bool wakeup_needed;
 	unsigned pending_acks;
 	struct kvm *kvm;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a51635e..fba4d93 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3010,18 +3010,18 @@ static int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
 	r = 0;
 	switch (chip->chip_id) {
 	case KVM_IRQCHIP_PIC_MASTER:
-		raw_spin_lock(&pic_irqchip(kvm)->lock);
+		spin_lock(&pic_irqchip(kvm)->lock);
 		memcpy(&pic_irqchip(kvm)->pics[0],
 			&chip->chip.pic,
 			sizeof(struct kvm_pic_state));
-		raw_spin_unlock(&pic_irqchip(kvm)->lock);
+		spin_unlock(&pic_irqchip(kvm)->lock);
 		break;
 	case KVM_IRQCHIP_PIC_SLAVE:
-		raw_spin_lock(&pic_irqchip(kvm)->lock);
+		spin_lock(&pic_irqchip(kvm)->lock);
 		memcpy(&pic_irqchip(kvm)->pics[1],
 			&chip->chip.pic,
 			sizeof(struct kvm_pic_state));
-		raw_spin_unlock(&pic_irqchip(kvm)->lock);
+		spin_unlock(&pic_irqchip(kvm)->lock);
 		break;
 	case KVM_IRQCHIP_IOAPIC:
 		r = kvm_set_ioapic(kvm, &chip->chip.ioapic);
-- 
1.7.2.3

Re: [PATCH] KVM: Convert PIC lock from raw spinlock to ordinary spinlock

[Marcelo Tosatti]

On Sun, Sep 19, 2010 at 06:44:07PM +0200, Avi Kivity wrote:
> The PIC code used to be called from preempt_disable() context, which
> wasn't very good for PREEMPT_RT.  That is no longer the case, so move
> back from raw_spinlock_t to spinlock_t.
> 
> Signed-off-by: Avi Kivity <avi@redhat.com>
> ---
>  arch/x86/kvm/i8259.c |    6 +++---
>  arch/x86/kvm/irq.h   |    2 +-
>  arch/x86/kvm/x86.c   |    8 ++++----
>  3 files changed, 8 insertions(+), 8 deletions(-)

Applied, thanks.