From 50a085bdd48af08cc7e3178ba0d7c1d5d8191698 Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Wed, 24 Feb 2010 10:41:58 +0100 Subject: [PATCH] KVM: x86: Kick VCPU outside PIC lock again This restores the deferred VCPU kicking before 956f97cf. We need this over -rt as wake_up* requires non-atomic context in this configuration. Signed-off-by: Jan Kiszka Signed-off-by: Avi Kivity --- arch/x86/kvm/i8259.c | 53 +++++++++++++++++++++++++++++++------------- arch/x86/kvm/irq.h | 1 + 2 files changed, 39 insertions(+), 15 deletions(-) diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c index a790fa128a9f..93825ff3338f 100644 --- a/arch/x86/kvm/i8259.c +++ b/arch/x86/kvm/i8259.c @@ -33,6 +33,29 @@ #include #include "trace.h" +static void pic_lock(struct kvm_pic *s) + __acquires(&s->lock) +{ + raw_spin_lock(&s->lock); +} + +static void pic_unlock(struct kvm_pic *s) + __releases(&s->lock) +{ + bool wakeup = s->wakeup_needed; + struct kvm_vcpu *vcpu; + + s->wakeup_needed = false; + + raw_spin_unlock(&s->lock); + + if (wakeup) { + vcpu = s->kvm->bsp_vcpu; + if (vcpu) + kvm_vcpu_kick(vcpu); + } +} + static void pic_clear_isr(struct kvm_kpic_state *s, int irq) { s->isr &= ~(1 << irq); @@ -45,19 +68,19 @@ static void pic_clear_isr(struct kvm_kpic_state *s, int irq) * Other interrupt may be delivered to PIC while lock is dropped but * it should be safe since PIC state is already updated at this stage. */ - raw_spin_unlock(&s->pics_state->lock); + pic_unlock(s->pics_state); kvm_notify_acked_irq(s->pics_state->kvm, SELECT_PIC(irq), irq); - raw_spin_lock(&s->pics_state->lock); + pic_lock(s->pics_state); } void kvm_pic_clear_isr_ack(struct kvm *kvm) { struct kvm_pic *s = pic_irqchip(kvm); - raw_spin_lock(&s->lock); + pic_lock(s); s->pics[0].isr_ack = 0xff; s->pics[1].isr_ack = 0xff; - raw_spin_unlock(&s->lock); + pic_unlock(s); } /* @@ -158,9 +181,9 @@ static void pic_update_irq(struct kvm_pic *s) void kvm_pic_update_irq(struct kvm_pic *s) { - raw_spin_lock(&s->lock); + pic_lock(s); pic_update_irq(s); - raw_spin_unlock(&s->lock); + pic_unlock(s); } int kvm_pic_set_irq(void *opaque, int irq, int level) @@ -168,14 +191,14 @@ int kvm_pic_set_irq(void *opaque, int irq, int level) struct kvm_pic *s = opaque; int ret = -1; - raw_spin_lock(&s->lock); + pic_lock(s); if (irq >= 0 && irq < PIC_NUM_PINS) { ret = pic_set_irq1(&s->pics[irq >> 3], irq & 7, level); pic_update_irq(s); trace_kvm_pic_set_irq(irq >> 3, irq & 7, s->pics[irq >> 3].elcr, s->pics[irq >> 3].imr, ret == 0); } - raw_spin_unlock(&s->lock); + pic_unlock(s); return ret; } @@ -205,7 +228,7 @@ int kvm_pic_read_irq(struct kvm *kvm) int irq, irq2, intno; struct kvm_pic *s = pic_irqchip(kvm); - raw_spin_lock(&s->lock); + pic_lock(s); irq = pic_get_irq(&s->pics[0]); if (irq >= 0) { pic_intack(&s->pics[0], irq); @@ -230,7 +253,7 @@ int kvm_pic_read_irq(struct kvm *kvm) intno = s->pics[0].irq_base + irq; } pic_update_irq(s); - raw_spin_unlock(&s->lock); + pic_unlock(s); return intno; } @@ -444,7 +467,7 @@ static int picdev_write(struct kvm_io_device *this, printk(KERN_ERR "PIC: non byte write\n"); return 0; } - raw_spin_lock(&s->lock); + pic_lock(s); switch (addr) { case 0x20: case 0x21: @@ -457,7 +480,7 @@ static int picdev_write(struct kvm_io_device *this, elcr_ioport_write(&s->pics[addr & 1], addr, data); break; } - raw_spin_unlock(&s->lock); + pic_unlock(s); return 0; } @@ -474,7 +497,7 @@ static int picdev_read(struct kvm_io_device *this, printk(KERN_ERR "PIC: non byte read\n"); return 0; } - raw_spin_lock(&s->lock); + pic_lock(s); switch (addr) { case 0x20: case 0x21: @@ -488,7 +511,7 @@ static int picdev_read(struct kvm_io_device *this, break; } *(unsigned char *)val = data; - raw_spin_unlock(&s->lock); + pic_unlock(s); return 0; } @@ -505,7 +528,7 @@ static void pic_irq_request(void *opaque, int level) s->output = level; if (vcpu && level && (s->pics[0].isr_ack & (1 << irq))) { s->pics[0].isr_ack &= ~(1 << irq); - kvm_vcpu_kick(vcpu); + s->wakeup_needed = true; } } diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h index 34b15915754d..cd1f362f413d 100644 --- a/arch/x86/kvm/irq.h +++ b/arch/x86/kvm/irq.h @@ -63,6 +63,7 @@ struct kvm_kpic_state { struct kvm_pic { raw_spinlock_t lock; + bool wakeup_needed; unsigned pending_acks; struct kvm *kvm; struct kvm_kpic_state pics[2]; /* 0 is master pic, 1 is slave pic */ -- 2.20.1