Re: [PATCH v1 12/12] target/riscv: Support virtual time context synchronization

[Paolo Bonzini]

On 11/20/21 23:34, Richard Henderson wrote:

On 11/20/21 8:46 AM, Yifei Jiang wrote:

  const VMStateDescription vmstate_riscv_cpu = {
  .name = "cpu",
  .version_id = 3,
  .minimum_version_id = 3,
+    .post_load = cpu_post_load,
  .fields = (VMStateField[]) {
  VMSTATE_UINTTL_ARRAY(env.gpr, RISCVCPU, 32),
  VMSTATE_UINT64_ARRAY(env.fpr, RISCVCPU, 32),
@@ -211,6 +221,10 @@ const VMStateDescription vmstate_riscv_cpu = {
  VMSTATE_UINT64(env.mtohost, RISCVCPU),
  VMSTATE_UINT64(env.timecmp, RISCVCPU),
+    VMSTATE_UINT64(env.kvm_timer_time, RISCVCPU),
+    VMSTATE_UINT64(env.kvm_timer_compare, RISCVCPU),
+    VMSTATE_UINT64(env.kvm_timer_state, RISCVCPU),
+
  VMSTATE_END_OF_LIST()
  },


Can't alter VMStateDescription.fields without bumping version.

If this is really kvm-only state, consider placing it into a 
subsection.  But I worry about kvm-only state because ideally we'd be 
able to migrate between tcg and kvm (if only for debugging).


Where is this state stored for TCG?

Paolo

Re: [PATCH v1 12/12] target/riscv: Support virtual time context synchronization

[Richard Henderson]

On 11/20/21 8:46 AM, Yifei Jiang wrote:

  const VMStateDescription vmstate_riscv_cpu = {
  .name = "cpu",
  .version_id = 3,
  .minimum_version_id = 3,
+.post_load = cpu_post_load,
  .fields = (VMStateField[]) {
  VMSTATE_UINTTL_ARRAY(env.gpr, RISCVCPU, 32),
  VMSTATE_UINT64_ARRAY(env.fpr, RISCVCPU, 32),
@@ -211,6 +221,10 @@ const VMStateDescription vmstate_riscv_cpu = {
  VMSTATE_UINT64(env.mtohost, RISCVCPU),
  VMSTATE_UINT64(env.timecmp, RISCVCPU),
  
+VMSTATE_UINT64(env.kvm_timer_time, RISCVCPU),

+VMSTATE_UINT64(env.kvm_timer_compare, RISCVCPU),
+VMSTATE_UINT64(env.kvm_timer_state, RISCVCPU),
+
  VMSTATE_END_OF_LIST()
  },


Can't alter VMStateDescription.fields without bumping version.

If this is really kvm-only state, consider placing it into a subsection.  But I worry 
about kvm-only state because ideally we'd be able to migrate between tcg and kvm (if only 
for debugging).



r~

[PATCH v1 12/12] target/riscv: Support virtual time context synchronization

[Yifei Jiang]

Add virtual time context description to vmstate_riscv_cpu. After cpu being
loaded, virtual time context is updated to KVM.

Signed-off-by: Yifei Jiang 
Signed-off-by: Mingwang Li 
---
 target/riscv/machine.c | 14 ++
 1 file changed, 14 insertions(+)

diff --git a/target/riscv/machine.c b/target/riscv/machine.c
index ad8248ebfd..153215549b 100644
--- a/target/riscv/machine.c
+++ b/target/riscv/machine.c
@@ -164,10 +164,20 @@ static const VMStateDescription vmstate_pointermasking = {
 }
 };
 
+static int cpu_post_load(void *opaque, int version_id)
+{
+RISCVCPU *cpu = opaque;
+CPURISCVState *env = >env;
+
+env->kvm_timer_dirty = true;
+return 0;
+}
+
 const VMStateDescription vmstate_riscv_cpu = {
 .name = "cpu",
 .version_id = 3,
 .minimum_version_id = 3,
+.post_load = cpu_post_load,
 .fields = (VMStateField[]) {
 VMSTATE_UINTTL_ARRAY(env.gpr, RISCVCPU, 32),
 VMSTATE_UINT64_ARRAY(env.fpr, RISCVCPU, 32),
@@ -211,6 +221,10 @@ const VMStateDescription vmstate_riscv_cpu = {
 VMSTATE_UINT64(env.mtohost, RISCVCPU),
 VMSTATE_UINT64(env.timecmp, RISCVCPU),
 
+VMSTATE_UINT64(env.kvm_timer_time, RISCVCPU),
+VMSTATE_UINT64(env.kvm_timer_compare, RISCVCPU),
+VMSTATE_UINT64(env.kvm_timer_state, RISCVCPU),
+
 VMSTATE_END_OF_LIST()
 },
 .subsections = (const VMStateDescription * []) {
-- 
2.19.1