From: Gavin Shan <gs...@redhat.com>
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>
Reviewed-by: Peter Xu <pet...@redhat.com>
Tested-by: Zhenyu Zhang <zheny...@redhat.com>
Message-Id: <20230509022122.20888-4-gs...@redhat.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
accel/kvm/kvm-all.c | 76 ++++++++++++++++++++++++++++-----------------
1 file changed, 47 insertions(+), 29 deletions(-)
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index c3aaabf304d7..5d0de9d0a8f8 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -1462,6 +1462,50 @@ static int kvm_dirty_ring_reaper_init(KVMState *s)
return 0;
}
+static int kvm_dirty_ring_init(KVMState *s)
+{
+ uint32_t ring_size = s->kvm_dirty_ring_size;
+ uint64_t ring_bytes = ring_size * sizeof(struct kvm_dirty_gfn);
+ int ret;
+
+ s->kvm_dirty_ring_size = 0;
+ s->kvm_dirty_ring_bytes = 0;
+
+ /* Bail if the dirty ring size isn't specified */
+ if (!ring_size) {
+ return 0;
+ }
+
+ /*
+ * 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");
+ return 0;
+ }
+
+ if (ring_bytes > ret) {
+ error_report("KVM dirty ring size %" PRIu32 " too big "
+ "(maximum is %ld). Please use a smaller value.",
+ 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_size = ring_size;
+ s->kvm_dirty_ring_bytes = ring_bytes;
+
+ return 0;
+}
+
static void kvm_region_add(MemoryListener *listener,
MemoryRegionSection *section)
{
@@ -2531,35 +2575,9 @@ static int kvm_init(MachineState *ms)
* Enable KVM dirty ring if supported, otherwise fall back to
* 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;
}
/*
--
2.40.1
