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| author | Thomas Huth <thuth@linux.vnet.ibm.com> | 2014-10-01 14:48:42 +0200 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2014-10-28 13:08:59 +0100 |
| commit | a6b7e459ff6d569227980f711664f927100c73a8 (patch) | |
| tree | e453086ed69408f2573ad4470fc7fb5e401a309d | |
| parent | cac7f2429872d3733dc3f9915857b1691da2eb2f (diff) | |
| download | linux-a6b7e459ff6d569227980f711664f927100c73a8.tar.gz linux-a6b7e459ff6d569227980f711664f927100c73a8.tar.bz2 linux-a6b7e459ff6d569227980f711664f927100c73a8.zip | |
KVM: s390: Make the simple ipte mutex specific to a VM instead of global
The ipte-locking should be done for each VM seperately, not globally.
This way we avoid possible congestions when the simple ipte-lock is used
and multiple VMs are running.
Suggested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| -rw-r--r-- | arch/s390/include/asm/kvm_host.h | 2 | ||||
| -rw-r--r-- | arch/s390/kvm/gaccess.c | 20 | ||||
| -rw-r--r-- | arch/s390/kvm/kvm-s390.c | 1 |
3 files changed, 12 insertions, 11 deletions
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index 2175f911a73a..584b820eeaf8 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -434,6 +434,8 @@ struct kvm_arch{ int user_cpu_state_ctrl; struct s390_io_adapter *adapters[MAX_S390_IO_ADAPTERS]; wait_queue_head_t ipte_wq; + int ipte_lock_count; + struct mutex ipte_mutex; spinlock_t start_stop_lock; struct kvm_s390_crypto crypto; }; diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c index 0f961a1c64b3..c1424e8b7f09 100644 --- a/arch/s390/kvm/gaccess.c +++ b/arch/s390/kvm/gaccess.c @@ -207,8 +207,6 @@ union raddress { unsigned long pfra : 52; /* Page-Frame Real Address */ }; -static int ipte_lock_count; -static DEFINE_MUTEX(ipte_mutex); int ipte_lock_held(struct kvm_vcpu *vcpu) { @@ -216,16 +214,16 @@ int ipte_lock_held(struct kvm_vcpu *vcpu) if (vcpu->arch.sie_block->eca & 1) return ic->kh != 0; - return ipte_lock_count != 0; + return vcpu->kvm->arch.ipte_lock_count != 0; } static void ipte_lock_simple(struct kvm_vcpu *vcpu) { union ipte_control old, new, *ic; - mutex_lock(&ipte_mutex); - ipte_lock_count++; - if (ipte_lock_count > 1) + mutex_lock(&vcpu->kvm->arch.ipte_mutex); + vcpu->kvm->arch.ipte_lock_count++; + if (vcpu->kvm->arch.ipte_lock_count > 1) goto out; ic = &vcpu->kvm->arch.sca->ipte_control; do { @@ -238,16 +236,16 @@ static void ipte_lock_simple(struct kvm_vcpu *vcpu) new.k = 1; } while (cmpxchg(&ic->val, old.val, new.val) != old.val); out: - mutex_unlock(&ipte_mutex); + mutex_unlock(&vcpu->kvm->arch.ipte_mutex); } static void ipte_unlock_simple(struct kvm_vcpu *vcpu) { union ipte_control old, new, *ic; - mutex_lock(&ipte_mutex); - ipte_lock_count--; - if (ipte_lock_count) + mutex_lock(&vcpu->kvm->arch.ipte_mutex); + vcpu->kvm->arch.ipte_lock_count--; + if (vcpu->kvm->arch.ipte_lock_count) goto out; ic = &vcpu->kvm->arch.sca->ipte_control; do { @@ -256,7 +254,7 @@ static void ipte_unlock_simple(struct kvm_vcpu *vcpu) } while (cmpxchg(&ic->val, old.val, new.val) != old.val); wake_up(&vcpu->kvm->arch.ipte_wq); out: - mutex_unlock(&ipte_mutex); + mutex_unlock(&vcpu->kvm->arch.ipte_mutex); } static void ipte_lock_siif(struct kvm_vcpu *vcpu) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 55aade49b6d1..3e83d4b357b9 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -453,6 +453,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) spin_lock_init(&kvm->arch.float_int.lock); INIT_LIST_HEAD(&kvm->arch.float_int.list); init_waitqueue_head(&kvm->arch.ipte_wq); + mutex_init(&kvm->arch.ipte_mutex); debug_register_view(kvm->arch.dbf, &debug_sprintf_view); VM_EVENT(kvm, 3, "%s", "vm created"); |