brain-hackers_pepepper-mirror
/
linux-brain
mirror of https://github.com/brain-hackers/linux-brain.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

KVM: keep track of which task is running a KVM vcpu 

Keep track of which task is running a KVM vcpu.  This helps us
figure out later what task to wake up if we want to boost a
vcpu that got preempted.

Unfortunately there are no guarantees that the same task
always keeps the same vcpu, so we can only track the task
across a single "run" of the vcpu.

Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Rik van Riel 2011-02-01 09:52:41 -05:00 committed by Marcelo Tosatti
parent 77c100c83e
commit 34bb10b79d
2 changed files with 11 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
include/linux/kvm_host.h
View File

@ -122,6 +122,7 @@ struct kvm_vcpu {
int fpu_active;
int guest_fpu_loaded, guest_xcr0_loaded;
wait_queue_head_t wq;
struct pid *pid;
int sigset_active;
sigset_t sigset;
struct kvm_vcpu_stat stat;

10
virt/kvm/kvm_main.c
View File

@ -137,6 +137,14 @@ void vcpu_load(struct kvm_vcpu *vcpu)
int cpu;
mutex_lock(&vcpu->mutex);
if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
/* The thread running this VCPU changed. */
struct pid *oldpid = vcpu->pid;
struct pid *newpid = get_task_pid(current, PIDTYPE_PID);
rcu_assign_pointer(vcpu->pid, newpid);
synchronize_rcu();
put_pid(oldpid);
}
cpu = get_cpu();
preempt_notifier_register(&vcpu->preempt_notifier);
kvm_arch_vcpu_load(vcpu, cpu);
@ -212,6 +220,7 @@ int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
vcpu->cpu = -1;
vcpu->kvm = kvm;
vcpu->vcpu_id = id;
vcpu->pid = NULL;
init_waitqueue_head(&vcpu->wq);
kvm_async_pf_vcpu_init(vcpu);
@ -236,6 +245,7 @@ EXPORT_SYMBOL_GPL(kvm_vcpu_init);
void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
{
put_pid(vcpu->pid);
kvm_arch_vcpu_uninit(vcpu);
free_page((unsigned long)vcpu->run);
}