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: s390: step the VCPU timer while in enabled wait 

The cpu timer is a mean to measure task execution time. We want
to account everything for a VCPU for which it is responsible. Therefore,
if the VCPU wants to sleep, it shall be accounted for it.

We can easily get this done by not disabling cpu timer accounting when
scheduled out while sleeping because of enabled wait.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This commit is contained in:
David Hildenbrand 2016-02-22 13:52:27 +01:00 committed by Christian Borntraeger
parent 9c23a1318e
commit 5ebda31686
2 changed files with 7 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
arch/s390/kvm/kvm-s390.c
View File

@ -1538,7 +1538,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
restore_access_regs(vcpu->run->s.regs.acrs);
gmap_enable(vcpu->arch.gmap);
atomic_or(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
if (vcpu->arch.cputm_enabled)
if (vcpu->arch.cputm_enabled && !is_vcpu_idle(vcpu))
__start_cpu_timer_accounting(vcpu);
vcpu->cpu = cpu;
}
@ -1546,7 +1546,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
vcpu->cpu = -1;
if (vcpu->arch.cputm_enabled)
if (vcpu->arch.cputm_enabled && !is_vcpu_idle(vcpu))
__stop_cpu_timer_accounting(vcpu);
atomic_andnot(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
gmap_disable(vcpu->arch.gmap);

5
arch/s390/kvm/kvm-s390.h
View File

@ -54,6 +54,11 @@ static inline int is_vcpu_stopped(struct kvm_vcpu *vcpu)
return atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_STOPPED;
}
static inline int is_vcpu_idle(struct kvm_vcpu *vcpu)
{
return atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_WAIT;
}
static inline int kvm_is_ucontrol(struct kvm *kvm)
{
#ifdef CONFIG_KVM_S390_UCONTROL