Import QEMU upstream snapshot d2e570c

Upstream: https://gitlab.com/qemu-project/qemu.git

Upstream-Commit: d2e570cc0f97b936902a5b1b86b73c0f5998b475

accel/dummy-cpus.c

@@ -0,0 +1,79 @@
+/*
+ * Dummy cpu thread code
+ *
+ * Copyright IBM, Corp. 2011
+ *
+ * Authors:
+ *  Anthony Liguori   <[email protected]>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/rcu.h"
+#include "system/cpus.h"
+#include "qemu/guest-random.h"
+#include "qemu/main-loop.h"
+#include "hw/core/cpu.h"
+#include "accel/dummy-cpus.h"
+
+static void *dummy_cpu_thread_fn(void *arg)
+{
+    CPUState *cpu = arg;
+
+    rcu_register_thread();
+
+    bql_lock();
+    qemu_thread_get_self(cpu->thread);
+    cpu->thread_id = qemu_get_thread_id();
+    current_cpu = cpu;
+
+#ifndef _WIN32
+    sigset_t waitset;
+    int r;
+
+    sigemptyset(&waitset);
+    sigaddset(&waitset, SIG_IPI);
+#endif
+
+    /* signal CPU creation */
+    cpu_thread_signal_created(cpu);
+    qemu_guest_random_seed_thread_part2(cpu->random_seed);
+
+    do {
+        qemu_process_cpu_events(cpu);
+        bql_unlock();
+#ifndef _WIN32
+        do {
+            int sig;
+            r = sigwait(&waitset, &sig);
+        } while (r == -1 && (errno == EAGAIN || errno == EINTR));
+        if (r == -1) {
+            perror("sigwait");
+            exit(1);
+        }
+#else
+        qemu_sem_wait(&cpu->sem);
+#endif
+        bql_lock();
+    } while (!cpu->unplug);
+
+    bql_unlock();
+    rcu_unregister_thread();
+    return NULL;
+}
+
+void dummy_start_vcpu_thread(CPUState *cpu)
+{
+    char thread_name[VCPU_THREAD_NAME_SIZE];
+
+    snprintf(thread_name, VCPU_THREAD_NAME_SIZE, "CPU %d/DUMMY",
+             cpu->cpu_index);
+    qemu_thread_create(cpu->thread, thread_name, dummy_cpu_thread_fn, cpu,
+                       QEMU_THREAD_JOINABLE);
+#ifdef _WIN32
+    qemu_sem_init(&cpu->sem, 0);
+#endif
+}