[Qemu-devel] [patch 3/7] qemu: main thread does io and cpu thread is spawned

[mtosatti@redhat.com]

[-- Attachment #1: vcpus-on-thread --]
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Index: qemu/vl.c
===================================================================
--- qemu.orig/vl.c
+++ qemu/vl.c
@@ -3623,12 +3623,13 @@ static int wait_signal(int timeout)
 
 static int has_work(CPUState *env)
 {
-    int r = 0;
+    if (!vm_running)
+        return 0;
     if (!env->halted)
-        r = 1;
+        return 1;
     if (env->interrupt_request & (CPU_INTERRUPT_HARD | CPU_INTERRUPT_NMI))
-        r = 1;
-    return r;
+        return 1;
+    return 0;
 }
 
 static void qemu_wait_io_event(CPUState *env, int timeout)
@@ -3737,14 +3738,6 @@ void main_loop_break(void)
     qemu_thread_signal(&io_thread, SIG_IPI);
 }
 
-static void *io_thread_fn(void *arg)
-{
-    unblock_io_signals();
-    qemu_mutex_lock(&qemu_global_mutex);
-    while (1)
-        main_loop_wait(1000);
-}
-
 static void qemu_signal_lock(unsigned int msecs)
 {
     qemu_mutex_lock(&qemu_fair_mutex);
@@ -3842,9 +3835,11 @@ void main_loop_wait(int timeout)
 #endif
 
     /* vm time timers */
-    if (vm_running && likely(!(cur_cpu->singlestep_enabled & SSTEP_NOTIMER)))
-        qemu_run_timers(&active_timers[QEMU_TIMER_VIRTUAL],
-                        qemu_get_clock(vm_clock));
+    if (vm_running) {
+        if (cur_cpu && likely(!(cur_cpu->singlestep_enabled & SSTEP_NOTIMER)))
+            qemu_run_timers(&active_timers[QEMU_TIMER_VIRTUAL],
+                             qemu_get_clock(vm_clock));
+    }
 
     /* real time timers */
     qemu_run_timers(&active_timers[QEMU_TIMER_REALTIME],
@@ -3856,7 +3851,7 @@ void main_loop_wait(int timeout)
 
 }
 
-static int main_loop(void)
+static void *cpu_main_loop(void *arg)
 {
     int ret, timeout;
 #ifdef CONFIG_PROFILER
@@ -3864,15 +3859,11 @@ static int main_loop(void)
 #endif
     CPUState *env;
 
-    qemu_mutex_init(&qemu_fair_mutex);
-    qemu_mutex_init(&qemu_global_mutex);
-    qemu_mutex_lock(&qemu_global_mutex);
-
-    qemu_thread_create(&io_thread, io_thread_fn, NULL);
     block_io_signals();
-
     qemu_thread_self(&cpus_thread);
 
+    qemu_mutex_lock(&qemu_global_mutex);
+
     cur_cpu = first_cpu;
     next_cpu = cur_cpu->next_cpu ?: first_cpu;
     for(;;) {
@@ -4011,7 +4002,23 @@ static int main_loop(void)
 #endif
     }
     cpu_disable_ticks();
-    return ret;
+    return NULL;
+}
+
+static void main_loop(void)
+{
+    qemu_mutex_init(&qemu_fair_mutex);
+    qemu_mutex_init(&qemu_global_mutex);
+    qemu_mutex_lock(&qemu_global_mutex);
+
+    qemu_thread_self(&io_thread);
+
+    unblock_io_signals();
+
+    qemu_thread_create(&cpus_thread, cpu_main_loop, NULL);
+
+    while (1)
+        main_loop_wait(1000);
 }
 
 static void help(int exitcode)

--