tracing: Add function-trace option to disable function tracing of latency tracers
[platform/adaptation/renesas_rcar/renesas_kernel.git] / block / elevator.c
index c2d61d5..603b2c1 100644 (file)
@@ -100,14 +100,14 @@ static void elevator_put(struct elevator_type *e)
        module_put(e->elevator_owner);
 }
 
-static struct elevator_type *elevator_get(const char *name)
+static struct elevator_type *elevator_get(const char *name, bool try_loading)
 {
        struct elevator_type *e;
 
        spin_lock(&elv_list_lock);
 
        e = elevator_find(name);
-       if (!e) {
+       if (!e && try_loading) {
                spin_unlock(&elv_list_lock);
                request_module("%s-iosched", name);
                spin_lock(&elv_list_lock);
@@ -207,25 +207,30 @@ int elevator_init(struct request_queue *q, char *name)
        q->boundary_rq = NULL;
 
        if (name) {
-               e = elevator_get(name);
+               e = elevator_get(name, true);
                if (!e)
                        return -EINVAL;
        }
 
+       /*
+        * Use the default elevator specified by config boot param or
+        * config option.  Don't try to load modules as we could be running
+        * off async and request_module() isn't allowed from async.
+        */
        if (!e && *chosen_elevator) {
-               e = elevator_get(chosen_elevator);
+               e = elevator_get(chosen_elevator, false);
                if (!e)
                        printk(KERN_ERR "I/O scheduler %s not found\n",
                                                        chosen_elevator);
        }
 
        if (!e) {
-               e = elevator_get(CONFIG_DEFAULT_IOSCHED);
+               e = elevator_get(CONFIG_DEFAULT_IOSCHED, false);
                if (!e) {
                        printk(KERN_ERR
                                "Default I/O scheduler not found. " \
                                "Using noop.\n");
-                       e = elevator_get("noop");
+                       e = elevator_get("noop", false);
                }
        }
 
@@ -967,7 +972,7 @@ int elevator_change(struct request_queue *q, const char *name)
                return -ENXIO;
 
        strlcpy(elevator_name, name, sizeof(elevator_name));
-       e = elevator_get(strstrip(elevator_name));
+       e = elevator_get(strstrip(elevator_name), true);
        if (!e) {
                printk(KERN_ERR "elevator: type %s not found\n", elevator_name);
                return -EINVAL;