KVM: Move vcpu alloc and init invocation to common code

Now that all architectures tightly couple vcpu allocation/free with the
mandatory calls to kvm_{un}init_vcpu(), move the sequences verbatim to
common KVM code.

Move both allocation and initialization in a single patch to eliminate
thrash in arch specific code.  The bisection benefits of moving the two
pieces in separate patches is marginal at best, whereas the odds of
introducing a transient arch specific bug are non-zero.

Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 8546bc6..92c9321 100644 (file)
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -285,25 +285,14 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
        return 0;
 }
 
-struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
+int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 {
        int err, size;
        void *gebase, *p, *handler, *refill_start, *refill_end;
        int i;
 
-       struct kvm_vcpu *vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
-
-       if (!vcpu) {
-               err = -ENOMEM;
-               goto out;
-       }
-
-       err = kvm_vcpu_init(vcpu, kvm, id);
-
-       if (err)
-               goto out_free_cpu;
-
-       kvm_debug("kvm @ %p: create cpu %d at %p\n", kvm, id, vcpu);
+       kvm_debug("kvm @ %p: create cpu %d at %p\n",
+                 vcpu->kvm, vcpu->vcpu_id, vcpu);
 
        /*
         * Allocate space for host mode exception handlers that handle
@@ -318,7 +307,7 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
 
        if (!gebase) {
                err = -ENOMEM;
-               goto out_uninit_cpu;
+               goto out;
        }
        kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
                  ALIGN(size, PAGE_SIZE), gebase);
@@ -397,19 +386,12 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
        vcpu->arch.last_sched_cpu = -1;
        vcpu->arch.last_exec_cpu = -1;
 
-       return vcpu;
+       return 0;
 
 out_free_gebase:
        kfree(gebase);
-
-out_uninit_cpu:
-       kvm_vcpu_uninit(vcpu);
-
-out_free_cpu:
-       kmem_cache_free(kvm_vcpu_cache, vcpu);
-
 out:
-       return ERR_PTR(err);
+       return err;
 }
 
 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
@@ -421,9 +403,6 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
        kvm_mmu_free_memory_caches(vcpu);
        kfree(vcpu->arch.guest_ebase);
        kfree(vcpu->arch.kseg0_commpage);
-
-       kvm_vcpu_uninit(vcpu);
-       kmem_cache_free(kvm_vcpu_cache, vcpu);
 }
 
 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,

diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index e3e2b88..fce1b47 100644 (file)
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -725,32 +725,17 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
        return 0;
 }
 
-struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
+int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 {
-       struct kvm_vcpu *vcpu;
        int err;
 
-       vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
-       if (!vcpu)
-               return ERR_PTR(-ENOMEM);
-
-       err = kvm_vcpu_init(vcpu, kvm, id);
-       if (err)
-               goto free_vcpu;
-
        err = kvmppc_core_vcpu_create(vcpu);
        if (err)
-               goto uninit_vcpu;
+               return err;
 
        vcpu->arch.wqp = &vcpu->wq;
-       kvmppc_create_vcpu_debugfs(vcpu, id);
-       return vcpu;
-
-uninit_vcpu:
-       kvm_vcpu_uninit(vcpu);
-free_vcpu:
-       kmem_cache_free(kvm_vcpu_cache, vcpu);
-       return ERR_PTR(err);
+       kvmppc_create_vcpu_debugfs(vcpu, vcpu->vcpu_id);
+       return 0;
 }
 
 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
@@ -780,10 +765,6 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
        }
 
        kvmppc_core_vcpu_free(vcpu);
-
-       kvm_vcpu_uninit(vcpu);
-
-       kmem_cache_free(kvm_vcpu_cache, vcpu);
 }
 
 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 8543d33..9cba1e5 100644 (file)
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -2530,9 +2530,6 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
        if (vcpu->kvm->arch.use_cmma)
                kvm_s390_vcpu_unsetup_cmma(vcpu);
        free_page((unsigned long)(vcpu->arch.sie_block));
-
-       kvm_vcpu_uninit(vcpu);
-       kmem_cache_free(kvm_vcpu_cache, vcpu);
 }
 
 static void kvm_free_vcpus(struct kvm *kvm)
@@ -3014,29 +3011,15 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
        return 0;
 }
 
-struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
-                                     unsigned int id)
+int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 {
-       struct kvm_vcpu *vcpu;
        struct sie_page *sie_page;
        int rc;
 
-       rc = -ENOMEM;
-
-       vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
-       if (!vcpu)
-               goto out;
-
-       rc = kvm_vcpu_init(vcpu, kvm, id);
-       if (rc)
-               goto out_free_cpu;
-
-       rc = -ENOMEM;
-
        BUILD_BUG_ON(sizeof(struct sie_page) != 4096);
        sie_page = (struct sie_page *) get_zeroed_page(GFP_KERNEL);
        if (!sie_page)
-               goto out_uninit_vcpu;
+               return -ENOMEM;
 
        vcpu->arch.sie_block = &sie_page->sie_block;
        vcpu->arch.sie_block->itdba = (unsigned long) &sie_page->itdb;
@@ -3045,9 +3028,9 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
        vcpu->arch.sie_block->mso = 0;
        vcpu->arch.sie_block->msl = sclp.hamax;
 
-       vcpu->arch.sie_block->icpua = id;
+       vcpu->arch.sie_block->icpua = vcpu->vcpu_id;
        spin_lock_init(&vcpu->arch.local_int.lock);
-       vcpu->arch.sie_block->gd = (u32)(u64)kvm->arch.gisa_int.origin;
+       vcpu->arch.sie_block->gd = (u32)(u64)vcpu->kvm->arch.gisa_int.origin;
        if (vcpu->arch.sie_block->gd && sclp.has_gisaf)
                vcpu->arch.sie_block->gd |= GISA_FORMAT1;
        seqcount_init(&vcpu->arch.cputm_seqcount);
@@ -3083,19 +3066,15 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
                        goto out_free_sie_block;
        }
 
-       VM_EVENT(kvm, 3, "create cpu %d at 0x%pK, sie block at 0x%pK", id, vcpu,
-                vcpu->arch.sie_block);
-       trace_kvm_s390_create_vcpu(id, vcpu, vcpu->arch.sie_block);
+       VM_EVENT(vcpu->kvm, 3, "create cpu %d at 0x%pK, sie block at 0x%pK",
+                vcpu->vcpu_id, vcpu, vcpu->arch.sie_block);
+       trace_kvm_s390_create_vcpu(vcpu->vcpu_id, vcpu, vcpu->arch.sie_block);
+
+       return 0;
 
-       return vcpu;
 out_free_sie_block:
        free_page((unsigned long)(vcpu->arch.sie_block));
-out_uninit_vcpu:
-       kvm_vcpu_uninit(vcpu);
-out_free_cpu:
-       kmem_cache_free(kvm_vcpu_cache, vcpu);
-out:
-       return ERR_PTR(rc);
+       return rc;
 }
 
 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 42b9149..7bbde6f 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9179,30 +9179,9 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
        return 0;
 }
 
-struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
-                                               unsigned int id)
+int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 {
-       struct kvm_vcpu *vcpu;
-       int r;
-
-       vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL_ACCOUNT);
-       if (!vcpu)
-               return ERR_PTR(-ENOMEM);
-
-       r = kvm_vcpu_init(vcpu, kvm, id);
-       if (r)
-               goto free_vcpu;
-
-       r = kvm_x86_ops->vcpu_create(vcpu);
-       if (r)
-               goto uninit_vcpu;
-       return vcpu;
-
-uninit_vcpu:
-       kvm_vcpu_uninit(vcpu);
-free_vcpu:
-       kmem_cache_free(kvm_vcpu_cache, vcpu);
-       return ERR_PTR(r);
+       return kvm_x86_ops->vcpu_create(vcpu);
 }
 
 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
@@ -9254,9 +9233,6 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
        free_cpumask_var(vcpu->arch.wbinvd_dirty_mask);
        kmem_cache_free(x86_fpu_cache, vcpu->arch.user_fpu);
        kmem_cache_free(x86_fpu_cache, vcpu->arch.guest_fpu);
-
-       kvm_vcpu_uninit(vcpu);
-       kmem_cache_free(kvm_vcpu_cache, vcpu);
 }
 
 void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 432827a..405ea07 100644 (file)
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -876,7 +876,7 @@ void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu);
 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu);
 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu);
 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id);
-struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id);
+int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu);
 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu);
 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu);
 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu);

diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index 0d8fb69..a7d661f 100644 (file)
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -290,32 +290,9 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
        return 0;
 }
 
-struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
+int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 {
-       int err;
-       struct kvm_vcpu *vcpu;
-
-       vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
-       if (!vcpu) {
-               err = -ENOMEM;
-               goto out;
-       }
-
-       err = kvm_vcpu_init(vcpu, kvm, id);
-       if (err)
-               goto free_vcpu;
-
-       err = create_hyp_mappings(vcpu, vcpu + 1, PAGE_HYP);
-       if (err)
-               goto vcpu_uninit;
-
-       return vcpu;
-vcpu_uninit:
-       kvm_vcpu_uninit(vcpu);
-free_vcpu:
-       kmem_cache_free(kvm_vcpu_cache, vcpu);
-out:
-       return ERR_PTR(err);
+       return create_hyp_mappings(vcpu, vcpu + 1, PAGE_HYP);
 }
 
 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
@@ -330,8 +307,6 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
        kvm_mmu_free_memory_caches(vcpu);
        kvm_timer_vcpu_terminate(vcpu);
        kvm_pmu_vcpu_destroy(vcpu);
-       kvm_vcpu_uninit(vcpu);
-       kmem_cache_free(kvm_vcpu_cache, vcpu);
 }
 
 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 62ba25e..c84df40 100644 (file)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -378,6 +378,9 @@ EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
 void kvm_vcpu_destroy(struct kvm_vcpu *vcpu)
 {
        kvm_arch_vcpu_destroy(vcpu);
+
+       kvm_vcpu_uninit(vcpu);
+       kmem_cache_free(kvm_vcpu_cache, vcpu);
 }
 EXPORT_SYMBOL_GPL(kvm_vcpu_destroy);
 
@@ -2738,12 +2741,20 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
        if (r)
                goto vcpu_decrement;
 
-       vcpu = kvm_arch_vcpu_create(kvm, id);
-       if (IS_ERR(vcpu)) {
-               r = PTR_ERR(vcpu);
+       vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
+       if (!vcpu) {
+               r = -ENOMEM;
                goto vcpu_decrement;
        }
 
+       r = kvm_vcpu_init(vcpu, kvm, id);
+       if (r)
+               goto vcpu_free;
+
+       r = kvm_arch_vcpu_create(vcpu);
+       if (r)
+               goto vcpu_uninit;
+
        preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
 
        r = kvm_arch_vcpu_setup(vcpu);
@@ -2787,6 +2798,10 @@ unlock_vcpu_destroy:
        debugfs_remove_recursive(vcpu->debugfs_dentry);
 vcpu_destroy:
        kvm_arch_vcpu_destroy(vcpu);
+vcpu_uninit:
+       kvm_vcpu_uninit(vcpu);
+vcpu_free:
+       kmem_cache_free(kvm_vcpu_cache, vcpu);
 vcpu_decrement:
        mutex_lock(&kvm->lock);
        kvm->created_vcpus--;