make elv_register() output atomic
Booting 2.6.21-rc3-g45592145 I noticed the following on one of my
machines in the bootlog:
io scheduler noop registered<6>Time: jiffies clocksource has been installed.
io scheduler deadline registered (default)
Looking at block/elevator.c, it appears that elv_register() uses two
consecutive printks in a non-atomic way, leading to the above glitch. The
attached trivial patch fixes this issue, by using a single printk.
Signed-off-by: Thibaut VARENE <varenet@parisc-linux.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/block/elevator.c b/block/elevator.c
index 25f6ef2..96a00c8 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -964,17 +964,18 @@
int elv_register(struct elevator_type *e)
{
+ char *def = "";
spin_lock_irq(&elv_list_lock);
BUG_ON(elevator_find(e->elevator_name));
list_add_tail(&e->list, &elv_list);
spin_unlock_irq(&elv_list_lock);
- printk(KERN_INFO "io scheduler %s registered", e->elevator_name);
if (!strcmp(e->elevator_name, chosen_elevator) ||
(!*chosen_elevator &&
!strcmp(e->elevator_name, CONFIG_DEFAULT_IOSCHED)))
- printk(" (default)");
- printk("\n");
+ def = " (default)";
+
+ printk(KERN_INFO "io scheduler %s registered%s\n", e->elevator_name, def);
return 0;
}
EXPORT_SYMBOL_GPL(elv_register);