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| author | David Hildenbrand <dahi@linux.vnet.ibm.com> | 2015-09-23 10:45:50 +0300 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2015-11-30 14:47:09 +0300 |
| commit | 2c1bb2be986c56848ce92ba41ba32fc62ab3165f (patch) | |
| tree | d993b44cd371b29a40f9b521fbe9cdafc225e1d7 | |
| parent | fe0edcb7311e80a349ad5f2b15f2d91a5606ed7f (diff) | |
| download | linux-2c1bb2be986c56848ce92ba41ba32fc62ab3165f.tar.xz | |
KVM: s390: fast path for sca_ext_call_pending
If CPUSTAT_ECALL_PEND isn't set, we can't have an external call pending,
so we can directly avoid taking the lock.
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>
| -rw-r--r-- | arch/s390/kvm/interrupt.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index 831c9ac728ec..62ec925aa196 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -39,6 +39,9 @@ static int sca_ext_call_pending(struct kvm_vcpu *vcpu, int *src_id) { int c, scn; + if (!(atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_ECALL_PEND)) + return 0; + read_lock(&vcpu->kvm->arch.sca_lock); if (vcpu->kvm->arch.use_esca) { struct esca_block *sca = vcpu->kvm->arch.sca; @@ -60,8 +63,7 @@ static int sca_ext_call_pending(struct kvm_vcpu *vcpu, int *src_id) if (src_id) *src_id = scn; - return c && atomic_read(&vcpu->arch.sie_block->cpuflags) & - CPUSTAT_ECALL_PEND; + return c; } static int sca_inject_ext_call(struct kvm_vcpu *vcpu, int src_id) |