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| author | David Hildenbrand <dahi@linux.vnet.ibm.com> | 2015-07-07 20:39:35 +0200 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2016-06-21 09:43:46 +0200 |
| commit | b917ae573f5b3f7fee8cfb0d42d74bd8641f6401 (patch) | |
| tree | f582eb7dc28567929d6a54185a53fac1036341bf /arch/s390 | |
| parent | 94a15de8fb2667791d66c49610676ea2add90034 (diff) | |
| download | linux-b917ae573f5b3f7fee8cfb0d42d74bd8641f6401.tar.gz linux-b917ae573f5b3f7fee8cfb0d42d74bd8641f6401.tar.bz2 linux-b917ae573f5b3f7fee8cfb0d42d74bd8641f6401.zip | |
KVM: s390: vsie: speed up VCPU external calls
Whenever a SIGP external call is injected via the SIGP external call
interpretation facility, the VCPU is not kicked. When a VCPU is currently
in the VSIE, the external call might not be processed immediately.
Therefore we have to provoke partial execution exceptions, which leads to a
kick of the VCPU and therefore also kick out of VSIE. This is done by
simulating the WAIT state. This bit has no other side effects.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/kvm/vsie.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c index c8c8763e7822..90781ba52803 100644 --- a/arch/s390/kvm/vsie.c +++ b/arch/s390/kvm/vsie.c @@ -844,6 +844,11 @@ static void register_shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) { WRITE_ONCE(vcpu->arch.vsie_block, &vsie_page->scb_s); + /* + * External calls have to lead to a kick of the vcpu and + * therefore the vsie -> Simulate Wait state. + */ + atomic_or(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags); } /* @@ -851,6 +856,7 @@ static void register_shadow_scb(struct kvm_vcpu *vcpu, */ static void unregister_shadow_scb(struct kvm_vcpu *vcpu) { + atomic_andnot(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags); WRITE_ONCE(vcpu->arch.vsie_block, NULL); } |