vl: merge -accel processing into configure_accelerators

The next step is to move the parsing of "-machine accel=..." into vl.c,
unifying it with the configure_accelerators() function that has just
been introduced.  This way, we will be able to desugar it into multiple
"-accel" options, without polluting accel/accel.c.

The CONFIG_TCG and CONFIG_KVM symbols are not available in vl.c, but
we can use accel_find instead to find their value at runtime.  Once we
know that the binary has one of TCG or KVM, the default accelerator
can be expressed simply as "tcg:kvm", because TCG never fails to initialize.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

accel/accel.c

@@ -28,13 +28,7 @@
 #include "hw/boards.h"
 #include "sysemu/arch_init.h"
 #include "sysemu/sysemu.h"
-#include "sysemu/kvm.h"
-#include "sysemu/qtest.h"
-#include "hw/xen/xen.h"
 #include "qom/object.h"
-#include "qemu/error-report.h"
-#include "qemu/option.h"
-#include "qapi/error.h"
 
 static const TypeInfo accel_type = {
     .name = TYPE_ACCEL,
@@ -44,7 +38,7 @@ static const TypeInfo accel_type = {
 };
 
 /* Lookup AccelClass from opt_name. Returns NULL if not found */
-static AccelClass *accel_find(const char *opt_name)
+AccelClass *accel_find(const char *opt_name)
 {
     char *class_name = g_strdup_printf(ACCEL_CLASS_NAME("%s"), opt_name);
     AccelClass *ac = ACCEL_CLASS(object_class_by_name(class_name));
@@ -52,7 +46,7 @@ static AccelClass *accel_find(const char *opt_name)
     return ac;
 }
 
-static int accel_init_machine(AccelClass *acc, MachineState *ms)
+int accel_init_machine(AccelClass *acc, MachineState *ms)
 {
     ObjectClass *oc = OBJECT_CLASS(acc);
     const char *cname = object_class_get_name(oc);
@@ -71,65 +65,6 @@ static int accel_init_machine(AccelClass *acc, MachineState *ms)
     return ret;
 }
 
-void configure_accelerator(MachineState *ms, const char *progname)
-{
-    const char *accel;
-    char **accel_list, **tmp;
-    int ret;
-    bool accel_initialised = false;
-    bool init_failed = false;
-    AccelClass *acc = NULL;
-
-    accel = qemu_opt_get(qemu_get_machine_opts(), "accel");
-    if (accel == NULL) {
-        /* Select the default accelerator */
-        int pnlen = strlen(progname);
-        if (pnlen >= 3 && g_str_equal(&progname[pnlen - 3], "kvm")) {
-            /* If the program name ends with "kvm", we prefer KVM */
-            accel = "kvm:tcg";
-        } else {
-#if defined(CONFIG_TCG)
-            accel = "tcg";
-#elif defined(CONFIG_KVM)
-            accel = "kvm";
-#else
-            error_report("No accelerator selected and"
-                         " no default accelerator available");
-            exit(1);
-#endif
-        }
-    }
-
-    accel_list = g_strsplit(accel, ":", 0);
-
-    for (tmp = accel_list; !accel_initialised && tmp && *tmp; tmp++) {
-        acc = accel_find(*tmp);
-        if (!acc) {
-            continue;
-        }
-        ret = accel_init_machine(acc, ms);
-        if (ret < 0) {
-            init_failed = true;
-            error_report("failed to initialize %s: %s",
-                         acc->name, strerror(-ret));
-        } else {
-            accel_initialised = true;
-        }
-    }
-    g_strfreev(accel_list);
-
-    if (!accel_initialised) {
-        if (!init_failed) {
-            error_report("-machine accel=%s: No accelerator found", accel);
-        }
-        exit(1);
-    }
-
-    if (init_failed) {
-        error_report("Back to %s accelerator", acc->name);
-    }
-}
-
 void accel_setup_post(MachineState *ms)
 {
     AccelState *accel = ms->accelerator;

include/sysemu/accel.h

@@ -66,7 +66,9 @@ typedef struct AccelClass {
 
 extern unsigned long tcg_tb_size;
 
-void configure_accelerator(MachineState *ms, const char *progname);
+AccelClass *accel_find(const char *opt_name);
+int accel_init_machine(AccelClass *acc, MachineState *ms);
+
 /* Called just before os_setup_post (ie just before drop OS privs) */
 void accel_setup_post(MachineState *ms);
 

vl.c

@@ -2714,8 +2714,65 @@ static int do_configure_accelerator(void *opaque, QemuOpts *opts, Error **errp)
     return 0;
 }
 
-static void configure_accelerators(void)
+static void configure_accelerators(const char *progname)
 {
+    const char *accel;
+    char **accel_list, **tmp;
+    int ret;
+    bool accel_initialised = false;
+    bool init_failed = false;
+    AccelClass *acc = NULL;
+
+    qemu_opts_foreach(qemu_find_opts("icount"),
+                      do_configure_icount, NULL, &error_fatal);
+
+    accel = qemu_opt_get(qemu_get_machine_opts(), "accel");
+    if (accel == NULL) {
+        /* Select the default accelerator */
+        if (!accel_find("tcg") && !accel_find("kvm")) {
+            error_report("No accelerator selected and"
+                         " no default accelerator available");
+            exit(1);
+        } else {
+            int pnlen = strlen(progname);
+            if (pnlen >= 3 && g_str_equal(&progname[pnlen - 3], "kvm")) {
+                /* If the program name ends with "kvm", we prefer KVM */
+                accel = "kvm:tcg";
+            } else {
+                accel = "tcg:kvm";
+            }
+        }
+    }
+
+    accel_list = g_strsplit(accel, ":", 0);
+
+    for (tmp = accel_list; !accel_initialised && tmp && *tmp; tmp++) {
+        acc = accel_find(*tmp);
+        if (!acc) {
+            continue;
+        }
+        ret = accel_init_machine(acc, current_machine);
+        if (ret < 0) {
+            init_failed = true;
+            error_report("failed to initialize %s: %s",
+                         acc->name, strerror(-ret));
+        } else {
+            accel_initialised = true;
+        }
+    }
+    g_strfreev(accel_list);
+
+    if (!accel_initialised) {
+        if (!init_failed) {
+            error_report("-machine accel=%s: No accelerator found", accel);
+        }
+        exit(1);
+    }
+
+    if (init_failed) {
+        error_report("Back to %s accelerator", acc->name);
+    }
+
     qemu_opts_foreach(qemu_find_opts("accel"),
                       do_configure_accelerator, NULL, &error_fatal);
 
@@ -4035,9 +4092,7 @@ int main(int argc, char **argv, char **envp)
      * Note: uses machine properties such as kernel-irqchip, must run
      * after machine_set_property().
      */
-    qemu_opts_foreach(qemu_find_opts("icount"),
+    configure_accelerators(argv[0]);
-                      do_configure_icount, NULL, &error_fatal);
-    configure_accelerator(current_machine, argv[0]);
 
     /*
      * Beware, QOM objects created before this point miss global and
@@ -4122,7 +4177,6 @@ int main(int argc, char **argv, char **envp)
     qemu_spice_init();
 
     cpu_ticks_init();
-    configure_accelerators();
 
     if (default_net) {
         QemuOptsList *net = qemu_find_opts("net");