Use schedule.

diff --git a/hellochar.c b/hellochar.c
index a197a1d..c3f26dc 100644 (file)
--- a/hellochar.c
+++ b/hellochar.c
@@ -41,7 +41,7 @@ static ssize_t hello_read(struct file *fp, char __user *buf, size_t sz,
 {
        unsigned long expire = jiffies + 5 * HZ;
        while (time_after(expire, jiffies))
-               cpu_relax();
+               schedule();
        return 0;
 }