KVM: s390: infrastructure to kick vcpus out of guest state

To ensure vcpu's come out of guest context in certain cases this patch adds a
s390 specific way to kick them out of guest context. Currently it kicks them
out to rerun the vcpu_run path in the s390 code, but the mechanism itself is
expandable and with a new flag we could also add e.g. kicks to userspace etc.

Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Christian Ehrhardt
2009-05-20 15:34:55 +02:00
committed by Avi Kivity
parent 3032b925f0
commit 9ace903d17
5 changed files with 55 additions and 28 deletions

View File

@@ -1,7 +1,7 @@
/*
* sigp.c - handlinge interprocessor communication
*
* Copyright IBM Corp. 2008
* Copyright IBM Corp. 2008,2009
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License (version 2 only)
@@ -9,6 +9,7 @@
*
* Author(s): Carsten Otte <cotte@de.ibm.com>
* Christian Borntraeger <borntraeger@de.ibm.com>
* Christian Ehrhardt <ehrhardt@de.ibm.com>
*/
#include <linux/kvm.h>
@@ -107,46 +108,57 @@ unlock:
return rc;
}
static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int store)
static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
{
struct kvm_s390_interrupt_info *inti;
inti = kzalloc(sizeof(*inti), GFP_KERNEL);
if (!inti)
return -ENOMEM;
inti->type = KVM_S390_SIGP_STOP;
spin_lock_bh(&li->lock);
list_add_tail(&inti->list, &li->list);
atomic_set(&li->active, 1);
atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
li->action_bits |= action;
if (waitqueue_active(&li->wq))
wake_up_interruptible(&li->wq);
spin_unlock_bh(&li->lock);
return 0; /* order accepted */
}
static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
{
struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
struct kvm_s390_local_interrupt *li;
struct kvm_s390_interrupt_info *inti;
int rc;
if (cpu_addr >= KVM_MAX_VCPUS)
return 3; /* not operational */
inti = kzalloc(sizeof(*inti), GFP_KERNEL);
if (!inti)
return -ENOMEM;
inti->type = KVM_S390_SIGP_STOP;
spin_lock(&fi->lock);
li = fi->local_int[cpu_addr];
if (li == NULL) {
rc = 3; /* not operational */
kfree(inti);
goto unlock;
}
spin_lock_bh(&li->lock);
list_add_tail(&inti->list, &li->list);
atomic_set(&li->active, 1);
atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
if (store)
li->action_bits |= ACTION_STORE_ON_STOP;
li->action_bits |= ACTION_STOP_ON_STOP;
if (waitqueue_active(&li->wq))
wake_up_interruptible(&li->wq);
spin_unlock_bh(&li->lock);
rc = 0; /* order accepted */
rc = __inject_sigp_stop(li, action);
unlock:
spin_unlock(&fi->lock);
VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
return rc;
}
int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action)
{
struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
return __inject_sigp_stop(li, action);
}
static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
{
int rc;
@@ -262,11 +274,11 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
break;
case SIGP_STOP:
vcpu->stat.instruction_sigp_stop++;
rc = __sigp_stop(vcpu, cpu_addr, 0);
rc = __sigp_stop(vcpu, cpu_addr, ACTION_STOP_ON_STOP);
break;
case SIGP_STOP_STORE_STATUS:
vcpu->stat.instruction_sigp_stop++;
rc = __sigp_stop(vcpu, cpu_addr, 1);
rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP);
break;
case SIGP_SET_ARCH:
vcpu->stat.instruction_sigp_arch++;