[PATCH v4 4/4] target/ppc: Add migration support for BHRB

[Glenn Miles <milesg@linux.vnet.ibm.com>]

Adds migration support for Branch History Rolling
Buffer (BHRB) internal state.

Signed-off-by: Glenn Miles <milesg@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
---

Changes from v3:
  - Rebased onto latest master branch

 target/ppc/machine.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/target/ppc/machine.c b/target/ppc/machine.c
index 6b6c31d903..731dd8df35 100644
--- a/target/ppc/machine.c
+++ b/target/ppc/machine.c
@@ -711,6 +711,26 @@ static const VMStateDescription vmstate_reservation = {
     }
 };
 
+#ifdef TARGET_PPC64
+static bool bhrb_needed(void *opaque)
+{
+    PowerPCCPU *cpu = opaque;
+    return (cpu->env.flags & POWERPC_FLAG_BHRB) != 0;
+}
+
+static const VMStateDescription vmstate_bhrb = {
+    .name = "cpu/bhrb",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = bhrb_needed,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINTTL(env.bhrb_offset, PowerPCCPU),
+        VMSTATE_UINT64_ARRAY(env.bhrb, PowerPCCPU, BHRB_MAX_NUM_ENTRIES),
+        VMSTATE_END_OF_LIST()
+    }
+};
+#endif
+
 const VMStateDescription vmstate_ppc_cpu = {
     .name = "cpu",
     .version_id = 5,
@@ -756,6 +776,7 @@ const VMStateDescription vmstate_ppc_cpu = {
 #ifdef TARGET_PPC64
         &vmstate_tm,
         &vmstate_slb,
+        &vmstate_bhrb,
 #endif /* TARGET_PPC64 */
         &vmstate_tlb6xx,
         &vmstate_tlbemb,
-- 
2.31.8