diff --git a/include/uc_priv.h b/include/uc_priv.h
index 22f494e4..45a9df9c 100644
--- a/include/uc_priv.h
+++ b/include/uc_priv.h
@@ -174,15 +174,22 @@ struct uc_struct {
 
     uc_insn_hook_validate insn_hook_validate;
 
-    MemoryRegion *system_memory;    // qemu/exec.c
-    MemoryRegion io_mem_rom;    // qemu/exec.c
-    MemoryRegion io_mem_notdirty;   // qemu/exec.c
-    MemoryRegion io_mem_unassigned; // qemu/exec.c
-    MemoryRegion io_mem_watch;  // qemu/exec.c
-    RAMList ram_list;   // qemu/exec.c
-    BounceBuffer bounce;    // qemu/cpu-exec.c
-    volatile sig_atomic_t exit_request; // qemu/cpu-exec.c
-    bool global_dirty_log;  // qemu/memory.c
+    // qemu/exec.c
+    MemoryRegion *system_memory;
+    MemoryRegion io_mem_rom;
+    MemoryRegion io_mem_notdirty;
+    MemoryRegion io_mem_unassigned;
+    MemoryRegion io_mem_watch;
+    RAMList ram_list;
+
+    // qemu/cpu-exec.c
+    BounceBuffer bounce;
+    volatile sig_atomic_t exit_request;
+    CPUState *tcg_current_cpu;
+
+    // qemu/memory.c
+    bool global_dirty_log;
+
     /* This is a multi-level map on the virtual address space.
        The bottom level has pointers to PageDesc.  */
     void **l1_map;  // qemu/translate-all.c
diff --git a/qemu/cpu-exec.c b/qemu/cpu-exec.c
index 0b9dfe81..f05eb27b 100644
--- a/qemu/cpu-exec.c
+++ b/qemu/cpu-exec.c
@@ -88,14 +88,7 @@ int cpu_exec(struct uc_struct *uc, CPUState *cpu)
     }
 
     uc->current_cpu = cpu;
-
-    /* As long as current_cpu is null, up to the assignment just above,
-     * requests by other threads to exit the execution loop are expected to
-     * be issued using the exit_request global. We must make sure that our
-     * evaluation of the global value is performed past the current_cpu
-     * value transition point, which requires a memory barrier as well as
-     * an instruction scheduling constraint on modern architectures.  */
-    smp_mb();
+    atomic_mb_set(&uc->tcg_current_cpu, cpu);
 
     if (unlikely(uc->exit_request)) {
         cpu->exit_request = 1;
@@ -295,6 +288,8 @@ int cpu_exec(struct uc_struct *uc, CPUState *cpu)
 
     /* fail safe : never use current_cpu outside cpu_exec() */
     uc->current_cpu = NULL;
+    /* Does not need atomic_mb_set because a spurious wakeup is okay.  */
+    atomic_set(&uc->tcg_current_cpu, NULL);
     return ret;
 }