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KVM: s390: call exit_sie() directly on vcpu block/request

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Thinking about it, I can't find a real use case where we want
to block a VCPU and not kick it out of SIE. (except if we want
to do the same in batch for multiple VCPUs - but that's a micro
optimization)

So let's simply perform the exit_sie() calls directly when setting
the other magic block bits in the SIE.

Otherwise e.g. kvm_s390_set_tod_low() still has other VCPUs running
after that call, working with a wrong epoch.

Fixes: 27406cd50c ("KVM: s390: provide functions for blocking all CPUs")
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>
This commit is contained in:
David Hildenbrand 2015-05-12 08:41:40 +02:00 committed by Christian Borntraeger
parent 06b36753a6
commit 61a6df54b6
1 changed files with 2 additions and 1 deletions
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3
arch/s390/kvm/kvm-s390.c
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@ -1417,6 +1417,7 @@ int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
void kvm_s390_vcpu_block(struct kvm_vcpu *vcpu) void kvm_s390_vcpu_block(struct kvm_vcpu *vcpu)
{ {
atomic_set_mask(PROG_BLOCK_SIE, &vcpu->arch.sie_block->prog20); atomic_set_mask(PROG_BLOCK_SIE, &vcpu->arch.sie_block->prog20);
exit_sie(vcpu);
} }
void kvm_s390_vcpu_unblock(struct kvm_vcpu *vcpu) void kvm_s390_vcpu_unblock(struct kvm_vcpu *vcpu)
@ -1427,6 +1428,7 @@ void kvm_s390_vcpu_unblock(struct kvm_vcpu *vcpu)
static void kvm_s390_vcpu_request(struct kvm_vcpu *vcpu) static void kvm_s390_vcpu_request(struct kvm_vcpu *vcpu)
{ {
atomic_set_mask(PROG_REQUEST, &vcpu->arch.sie_block->prog20); atomic_set_mask(PROG_REQUEST, &vcpu->arch.sie_block->prog20);
exit_sie(vcpu);
} }
static void kvm_s390_vcpu_request_handled(struct kvm_vcpu *vcpu) static void kvm_s390_vcpu_request_handled(struct kvm_vcpu *vcpu)
@ -1450,7 +1452,6 @@ void kvm_s390_sync_request(int req, struct kvm_vcpu *vcpu)
{ {
kvm_make_request(req, vcpu); kvm_make_request(req, vcpu);
kvm_s390_vcpu_request(vcpu); kvm_s390_vcpu_request(vcpu);
exit_sie(vcpu);
} }
static void kvm_gmap_notifier(struct gmap *gmap, unsigned long address) static void kvm_gmap_notifier(struct gmap *gmap, unsigned long address)