[PATCH v4 10/13] accel-ops: Introduce common_vcpu_thread_destroy() and .precheck handler

["Philippe Mathieu-Daudé" <philippe.mathieu.daude@gmail.com>]

From: Philippe Mathieu-Daudé <f4bug@amsat.org>

Introduce an empty common_vcpu_thread_destroy() function, and
provide a AccelOpsClass::destroy_vcpu_thread_precheck() callback
so accelerators can choose whether to call common_vcpu_thread_destroy.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 include/sysemu/accel-ops.h | 2 ++
 softmmu/cpus.c             | 9 +++++++++
 2 files changed, 11 insertions(+)

diff --git a/include/sysemu/accel-ops.h b/include/sysemu/accel-ops.h
index caf337f61f..b47f6de3f9 100644
--- a/include/sysemu/accel-ops.h
+++ b/include/sysemu/accel-ops.h
@@ -35,6 +35,8 @@ struct AccelOpsClass {
     /* If non-NULL, return whether common vCPU thread must be created */
     bool (*create_vcpu_thread_precheck)(CPUState *cpu);
     void (*create_vcpu_thread_postcheck)(CPUState *cpu);
+    /* If non-NULL, return whether common vCPU thread must be destroyed */
+    bool (*destroy_vcpu_thread_precheck)(CPUState *cpu);
 
     void (*kick_vcpu_thread)(CPUState *cpu);
     bool (*cpu_thread_is_idle)(CPUState *cpu);
diff --git a/softmmu/cpus.c b/softmmu/cpus.c
index cf430ac486..37325b3b8d 100644
--- a/softmmu/cpus.c
+++ b/softmmu/cpus.c
@@ -617,6 +617,10 @@ static void common_vcpu_thread_create(CPUState *cpu)
 #endif
 }
 
+static void common_vcpu_thread_destroy(CPUState *cpu)
+{
+}
+
 void cpu_remove_sync(CPUState *cpu)
 {
     cpu->stop = true;
@@ -625,6 +629,11 @@ void cpu_remove_sync(CPUState *cpu)
     qemu_mutex_unlock_iothread();
     qemu_thread_join(cpu->thread);
     qemu_mutex_lock_iothread();
+
+    if (cpus_accel->destroy_vcpu_thread_precheck == NULL
+            || cpus_accel->destroy_vcpu_thread_precheck(cpu)) {
+        common_vcpu_thread_destroy(cpu);
+    }
 }
 
 void cpus_register_accel(const AccelOpsClass *ops)
-- 
2.35.1