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| author | QingFeng Hao <haoqf@linux.vnet.ibm.com> | 2017-09-29 12:41:51 +0200 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2017-10-09 11:15:35 +0200 |
| commit | 9fb6c9b3fea1b1d1c6f14178373e8f7235f3b681 (patch) | |
| tree | 9b530f5034bad26c87adf9b17919d01438e20e18 /arch/s390/kvm | |
| parent | s390/sthyi: reorganize sthyi implementation (diff) | |
| download | linux-9fb6c9b3fea1b1d1c6f14178373e8f7235f3b681.tar.xz linux-9fb6c9b3fea1b1d1c6f14178373e8f7235f3b681.zip | |
s390/sthyi: add cache to store hypervisor info
STHYI requires extensive locking in the higher hypervisors and is
very computational/memory expensive. Therefore we cache the retrieved
hypervisor info whose valid period is 1s with mutex to allow concurrent
access. rw semaphore can't benefit here due to cache line bounce.
Signed-off-by: QingFeng Hao <haoqf@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/kvm')
| -rw-r--r-- | arch/s390/kvm/intercept.c | 10 | ||||
| -rw-r--r-- | arch/s390/kvm/kvm-s390.c | 2 |
2 files changed, 0 insertions, 12 deletions
diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c index 46adda5e2b2c..8fe034beb623 100644 --- a/arch/s390/kvm/intercept.c +++ b/arch/s390/kvm/intercept.c @@ -375,16 +375,6 @@ int handle_sthyi(struct kvm_vcpu *vcpu) if (!test_kvm_facility(vcpu->kvm, 74)) return kvm_s390_inject_program_int(vcpu, PGM_OPERATION); - /* - * STHYI requires extensive locking in the higher hypervisors - * and is very computational/memory expensive. Therefore we - * ratelimit the executions per VM. - */ - if (!__ratelimit(&vcpu->kvm->arch.sthyi_limit)) { - kvm_s390_retry_instr(vcpu); - return 0; - } - kvm_s390_get_regs_rre(vcpu, ®1, ®2); code = vcpu->run->s.regs.gprs[reg1]; addr = vcpu->run->s.regs.gprs[reg2]; diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 40d0a1a97889..de6a5b790da0 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -1884,8 +1884,6 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) rc = -ENOMEM; - ratelimit_state_init(&kvm->arch.sthyi_limit, 5 * HZ, 500); - kvm->arch.use_esca = 0; /* start with basic SCA */ if (!sclp.has_64bscao) alloc_flags |= GFP_DMA; |