Gavin Shan <gs...@redhat.com> wrote: > Due to multiple capabilities associated with the dirty ring for different > architectures: KVM_CAP_DIRTY_{LOG_RING, LOG_RING_ACQ_REL} for x86 and > arm64 separately. There will be more to be done in order to support the > dirty ring for arm64. > > Lets add helper kvm_dirty_ring_init() to enable the dirty ring. With this, > the code looks a bit clean. > > No functional change intended. > > Signed-off-by: Gavin Shan <gs...@redhat.com> > --- > accel/kvm/kvm-all.c | 73 ++++++++++++++++++++++++++++----------------- > 1 file changed, 46 insertions(+), 27 deletions(-) > > diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c > index 9ec117c441..399ef0f7e6 100644 > --- a/accel/kvm/kvm-all.c > +++ b/accel/kvm/kvm-all.c > @@ -1476,6 +1476,49 @@ static int kvm_dirty_ring_reaper_init(KVMState *s) > return 0; > } > > +static int kvm_dirty_ring_init(KVMState *s) > +{ > + uint64_t ring_bytes; > + int ret; > + > + /* > + * Read the max supported pages. Fall back to dirty logging mode > + * if the dirty ring isn't supported. > + */ > + ret = kvm_vm_check_extension(s, KVM_CAP_DIRTY_LOG_RING); > + if (ret <= 0) { > + warn_report("KVM dirty ring not available, using bitmap method"); > + s->kvm_dirty_ring_size = 0; > + return 0; > + } > + > + ring_bytes = s->kvm_dirty_ring_size * sizeof(struct kvm_dirty_gfn); > + if (ring_bytes > ret) { > + error_report("KVM dirty ring size %" PRIu32 " too big " > + "(maximum is %ld). Please use a smaller value.", > + s->kvm_dirty_ring_size, > + (long)ret / sizeof(struct kvm_dirty_gfn)); > + ret = -EINVAL; > + goto out; > + } > + > + ret = kvm_vm_enable_cap(s, KVM_CAP_DIRTY_LOG_RING, 0, ring_bytes); > + if (ret) { > + error_report("Enabling of KVM dirty ring failed: %s. " > + "Suggested minimum value is 1024.", strerror(-ret)); > + ret = -EIO; > + } > + > +out: > + if (ret) { > + s->kvm_dirty_ring_size = 0; > + } else { > + s->kvm_dirty_ring_bytes = ring_bytes; > + } > + > + return ret; > +}
If you split it, you don't need the goto. static int kvm_dirty_ring_init(KVMState *s) { s->kvm_dirty_ring_size = 0; /* * Read the max supported pages. Fall back to dirty logging mode * if the dirty ring isn't supported. */ int ret = kvm_vm_check_extension(s, KVM_CAP_DIRTY_LOG_RING); if (ret <= 0) { warn_report("KVM dirty ring not available, using bitmap method"); return 0; } uint64_t ring_bytes = s->kvm_dirty_ring_size * sizeof(struct kvm_dirty_gfn); if (ring_bytes > ret) { error_report("KVM dirty ring size %" PRIu32 " too big " "(maximum is %ld). Please use a smaller value.", s->kvm_dirty_ring_size, (long)ret / sizeof(struct kvm_dirty_gfn)); return -EINVAL; } ret = kvm_vm_enable_cap(s, KVM_CAP_DIRTY_LOG_RING, 0, ring_bytes); if (ret) { error_report("Enabling of KVM dirty ring failed: %s. " "Suggested minimum value is 1024.", strerror(-ret)); return -EIO; } s->kvm_dirty_ring_bytes = ring_bytes; return ret; } > + > static void kvm_region_add(MemoryListener *listener, > MemoryRegionSection *section) > { > @@ -2545,33 +2588,9 @@ static int kvm_init(MachineState *ms) > * dirty logging mode > */ > if (s->kvm_dirty_ring_size > 0) { > - uint64_t ring_bytes; > - > - ring_bytes = s->kvm_dirty_ring_size * sizeof(struct kvm_dirty_gfn); > - > - /* Read the max supported pages */ > - ret = kvm_vm_check_extension(s, KVM_CAP_DIRTY_LOG_RING); > - if (ret > 0) { > - if (ring_bytes > ret) { > - error_report("KVM dirty ring size %" PRIu32 " too big " > - "(maximum is %ld). Please use a smaller > value.", > - s->kvm_dirty_ring_size, > - (long)ret / sizeof(struct kvm_dirty_gfn)); > - ret = -EINVAL; > - goto err; > - } > - > - ret = kvm_vm_enable_cap(s, KVM_CAP_DIRTY_LOG_RING, 0, > ring_bytes); > - if (ret) { > - error_report("Enabling of KVM dirty ring failed: %s. " > - "Suggested minimum value is 1024.", > strerror(-ret)); > - goto err; > - } > - > - s->kvm_dirty_ring_bytes = ring_bytes; > - } else { > - warn_report("KVM dirty ring not available, using bitmap > method"); > - s->kvm_dirty_ring_size = 0; > + ret = kvm_dirty_ring_init(s); > + if (ret < 0) { > + goto err; > } > }