This patch adds a barrier() to prevent the compiler from
moving the read outside of the loop. It also fixes a comment.
Signed-off-by: NGiuliano Pochini <pochini@shiny.it>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NJaroslav Kysela <perex@suse.cz>