diff options
| author | Hollis Blanchard <hollisb@us.ibm.com> | 2008-04-25 17:55:49 -0500 |
|---|---|---|
| committer | Avi Kivity <avi@qumranet.com> | 2008-05-04 14:44:44 +0300 |
| commit | 45c5eb67da5a668abe79c23a7e64dbc87a600f90 (patch) | |
| tree | b2b9ff85ecb5b35d246d68da94b20cb9f9912bff | |
| parent | 3fe913e7c550a869e250d04c34410f7a6e263f7c (diff) | |
KVM: ppc: Handle guest idle by emulating MSR[WE] writes
This reduces host CPU usage when the guest is idle. However, the guest must
set MSR[WE] in its idle loop, which Linux did not do until 2.6.26.
Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Jerone Young <jyoung5@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
| -rw-r--r-- | arch/powerpc/kvm/booke_guest.c | 1 | ||||
| -rw-r--r-- | arch/powerpc/kvm/powerpc.c | 20 | ||||
| -rw-r--r-- | include/asm-powerpc/kvm_host.h | 1 | ||||
| -rw-r--r-- | include/asm-powerpc/kvm_ppc.h | 5 |
4 files changed, 24 insertions, 3 deletions
diff --git a/arch/powerpc/kvm/booke_guest.c b/arch/powerpc/kvm/booke_guest.c index 6d9884a6884..b3db6f4576a 100644 --- a/arch/powerpc/kvm/booke_guest.c +++ b/arch/powerpc/kvm/booke_guest.c @@ -49,6 +49,7 @@ struct kvm_stats_debugfs_item debugfs_entries[] = { { "inst_emu", VCPU_STAT(emulated_inst_exits) }, { "dec", VCPU_STAT(dec_exits) }, { "ext_intr", VCPU_STAT(ext_intr_exits) }, + { "halt_wakeup", VCPU_STAT(halt_wakeup) }, { NULL } }; diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index bad40bd2d3a..777e0f34e0e 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -36,13 +36,12 @@ gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn) int kvm_cpu_has_interrupt(struct kvm_vcpu *v) { - /* XXX implement me */ - return 0; + return !!(v->arch.pending_exceptions); } int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) { - return 1; + return !(v->arch.msr & MSR_WE); } @@ -214,6 +213,11 @@ static void kvmppc_decrementer_func(unsigned long data) struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data; kvmppc_queue_exception(vcpu, BOOKE_INTERRUPT_DECREMENTER); + + if (waitqueue_active(&vcpu->wq)) { + wake_up_interruptible(&vcpu->wq); + vcpu->stat.halt_wakeup++; + } } int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) @@ -339,6 +343,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) int r; sigset_t sigsaved; + vcpu_load(vcpu); + if (vcpu->sigset_active) sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved); @@ -363,12 +369,20 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) if (vcpu->sigset_active) sigprocmask(SIG_SETMASK, &sigsaved, NULL); + vcpu_put(vcpu); + return r; } int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, struct kvm_interrupt *irq) { kvmppc_queue_exception(vcpu, BOOKE_INTERRUPT_EXTERNAL); + + if (waitqueue_active(&vcpu->wq)) { + wake_up_interruptible(&vcpu->wq); + vcpu->stat.halt_wakeup++; + } + return 0; } diff --git a/include/asm-powerpc/kvm_host.h b/include/asm-powerpc/kvm_host.h index 04ffbb8e0a3..81a69d71101 100644 --- a/include/asm-powerpc/kvm_host.h +++ b/include/asm-powerpc/kvm_host.h @@ -59,6 +59,7 @@ struct kvm_vcpu_stat { u32 emulated_inst_exits; u32 dec_exits; u32 ext_intr_exits; + u32 halt_wakeup; }; struct tlbe { diff --git a/include/asm-powerpc/kvm_ppc.h b/include/asm-powerpc/kvm_ppc.h index 7ac820308a7..b35a7e3ef97 100644 --- a/include/asm-powerpc/kvm_ppc.h +++ b/include/asm-powerpc/kvm_ppc.h @@ -77,12 +77,17 @@ static inline void kvmppc_clear_exception(struct kvm_vcpu *vcpu, int exception) clear_bit(priority, &vcpu->arch.pending_exceptions); } +/* Helper function for "full" MSR writes. No need to call this if only EE is + * changing. */ static inline void kvmppc_set_msr(struct kvm_vcpu *vcpu, u32 new_msr) { if ((new_msr & MSR_PR) != (vcpu->arch.msr & MSR_PR)) kvmppc_mmu_priv_switch(vcpu, new_msr & MSR_PR); vcpu->arch.msr = new_msr; + + if (vcpu->arch.msr & MSR_WE) + kvm_vcpu_block(vcpu); } #endif /* __POWERPC_KVM_PPC_H__ */ |