This code makes large use of barriers, which had quite vague
descriptions. Update the comments to make the choice of barrier and
reason for it more clear.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14220/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>