diff options
| -rw-r--r-- | arch/powerpc/include/asm/kvm_host.h | 2 | ||||
| -rw-r--r-- | arch/powerpc/kernel/asm-offsets.c | 1 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv.c | 47 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_rmhandlers.S | 19 |
4 files changed, 34 insertions, 35 deletions
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 83c44257b005..1517faac9b98 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -272,8 +272,6 @@ struct kvmppc_vcore { int n_runnable; int num_threads; int entry_exit_count; - int n_woken; - int nap_count; int napping_threads; int first_vcpuid; u16 pcpu; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 92ec3fcb3415..8aa824681d76 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -563,7 +563,6 @@ int main(void) DEFINE(VCPU_WORT, offsetof(struct kvm_vcpu, arch.wort)); DEFINE(VCPU_SHADOW_SRR1, offsetof(struct kvm_vcpu, arch.shadow_srr1)); DEFINE(VCORE_ENTRY_EXIT, offsetof(struct kvmppc_vcore, entry_exit_count)); - DEFINE(VCORE_NAP_COUNT, offsetof(struct kvmppc_vcore, nap_count)); DEFINE(VCORE_IN_GUEST, offsetof(struct kvmppc_vcore, in_guest)); DEFINE(VCORE_NAPPING_THREADS, offsetof(struct kvmppc_vcore, napping_threads)); DEFINE(VCORE_KVM, offsetof(struct kvmppc_vcore, kvm)); diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index fb4f16628a51..7c1335dca4a5 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -1729,8 +1729,10 @@ static int kvmppc_grab_hwthread(int cpu) tpaca = &paca[cpu]; /* Ensure the thread won't go into the kernel if it wakes */ - tpaca->kvm_hstate.hwthread_req = 1; tpaca->kvm_hstate.kvm_vcpu = NULL; + tpaca->kvm_hstate.napping = 0; + smp_wmb(); + tpaca->kvm_hstate.hwthread_req = 1; /* * If the thread is already executing in the kernel (e.g. handling @@ -1773,35 +1775,43 @@ static void kvmppc_start_thread(struct kvm_vcpu *vcpu) } cpu = vc->pcpu + vcpu->arch.ptid; tpaca = &paca[cpu]; - tpaca->kvm_hstate.kvm_vcpu = vcpu; tpaca->kvm_hstate.kvm_vcore = vc; tpaca->kvm_hstate.ptid = vcpu->arch.ptid; vcpu->cpu = vc->pcpu; + /* Order stores to hstate.kvm_vcore etc. before store to kvm_vcpu */ smp_wmb(); + tpaca->kvm_hstate.kvm_vcpu = vcpu; #if defined(CONFIG_PPC_ICP_NATIVE) && defined(CONFIG_SMP) - if (cpu != smp_processor_id()) { + if (cpu != smp_processor_id()) xics_wake_cpu(cpu); - if (vcpu->arch.ptid) - ++vc->n_woken; - } #endif } -static void kvmppc_wait_for_nap(struct kvmppc_vcore *vc) +static void kvmppc_wait_for_nap(void) { - int i; + int cpu = smp_processor_id(); + int i, loops; - HMT_low(); - i = 0; - while (vc->nap_count < vc->n_woken) { - if (++i >= 1000000) { - pr_err("kvmppc_wait_for_nap timeout %d %d\n", - vc->nap_count, vc->n_woken); - break; + for (loops = 0; loops < 1000000; ++loops) { + /* + * Check if all threads are finished. + * We set the vcpu pointer when starting a thread + * and the thread clears it when finished, so we look + * for any threads that still have a non-NULL vcpu ptr. + */ + for (i = 1; i < threads_per_subcore; ++i) + if (paca[cpu + i].kvm_hstate.kvm_vcpu) + break; + if (i == threads_per_subcore) { + HMT_medium(); + return; } - cpu_relax(); + HMT_low(); } HMT_medium(); + for (i = 1; i < threads_per_subcore; ++i) + if (paca[cpu + i].kvm_hstate.kvm_vcpu) + pr_err("KVM: CPU %d seems to be stuck\n", cpu + i); } /* @@ -1942,8 +1952,6 @@ static void kvmppc_run_core(struct kvmppc_vcore *vc) /* * Initialize *vc. */ - vc->n_woken = 0; - vc->nap_count = 0; vc->entry_exit_count = 0; vc->preempt_tb = TB_NIL; vc->in_guest = 0; @@ -2002,8 +2010,7 @@ static void kvmppc_run_core(struct kvmppc_vcore *vc) list_for_each_entry(vcpu, &vc->runnable_threads, arch.run_list) vcpu->cpu = -1; /* wait for secondary threads to finish writing their state to memory */ - if (vc->nap_count < vc->n_woken) - kvmppc_wait_for_nap(vc); + kvmppc_wait_for_nap(); for (i = 0; i < threads_per_subcore; ++i) kvmppc_release_hwthread(vc->pcpu + i); /* prevent other vcpu threads from doing kvmppc_start_thread() now */ diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index f8267e5b3a50..6716db3f1a2b 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -292,26 +292,21 @@ kvm_secondary_got_guest: ld r6, PACA_DSCR(r13) std r6, HSTATE_DSCR(r13) + /* Order load of vcore, ptid etc. after load of vcpu */ + lwsync bl kvmppc_hv_entry /* Back from the guest, go back to nap */ /* Clear our vcpu pointer so we don't come back in early */ li r0, 0 - std r0, HSTATE_KVM_VCPU(r13) /* - * Make sure we clear HSTATE_KVM_VCPU(r13) before incrementing - * the nap_count, because once the increment to nap_count is - * visible we could be given another vcpu. + * Once we clear HSTATE_KVM_VCPU(r13), the code in + * kvmppc_run_core() is going to assume that all our vcpu + * state is visible in memory. This lwsync makes sure + * that that is true. */ lwsync - - /* increment the nap count and then go to nap mode */ - ld r4, HSTATE_KVM_VCORE(r13) - addi r4, r4, VCORE_NAP_COUNT -51: lwarx r3, 0, r4 - addi r3, r3, 1 - stwcx. r3, 0, r4 - bne 51b + std r0, HSTATE_KVM_VCPU(r13) /* * At this point we have finished executing in the guest. |