block: rate-limit capacity change info log

loop devices under heavy stress-ng loop streessor can trigger many
capacity change events in a short time. Each event prints an info
message from set_capacity_and_notify(), flooding the console and
contributing to soft lockups on slow consoles.

Switch the printk in set_capacity_and_notify() to
pr_info_ratelimited() so frequent capacity changes do not spam
the log while still reporting occasional changes.

Cc: [email protected]
Signed-off-by: Li Chen <[email protected]>
Reviewed-by: Bart Van Assche <[email protected]>
Reviewed-by: Chaitanya Kulkarni <[email protected]>

Author: FirstLoveLife

block/genhd.c

@@ -90,7 +90,7 @@ bool set_capacity_and_notify(struct gendisk *disk, sector_t size)
 	    (disk->flags & GENHD_FL_HIDDEN))
 		return false;
 
-	pr_info("%s: detected capacity change from %lld to %lld\n",
+	pr_info_ratelimited("%s: detected capacity change from %lld to %lld\n",
 		disk->disk_name, capacity, size);
 
 	/*