Re: [linux-next] rootfs: rootflags take effect when mount rootfs

From: chenweilong
Date: Sun Jun 27 2021 - 21:47:59 EST


On 2021/6/27 18:46, Greg KH wrote:
> On Sat, Jun 26, 2021 at 09:16:55AM +0800, Weilong Chen wrote:
>> The kernel root filesystem may use the rootflags parameters
>> when mount, especially for tmpfs, to setup a variety of features.
>>
>> For example:
>> 1. Add 'rootflags=huge=always' to boot args.
>> 2. When the OS bootup:
>> rootfs on / type rootfs (..., huge=always)
>> Then we can get the hugepage performance improvement of tmpfs.
>>
>> Signed-off-by: Weilong Chen <chenweilong@xxxxxxxxxx>
>> ---
>> fs/namespace.c | 5 +++--
>> include/linux/init.h | 2 +-
>> init/do_mounts.c | 4 +++-
>> 3 files changed, 7 insertions(+), 4 deletions(-)
> No documentation update for this new user/kernel api you added?

There is already relevant documents (Documentation/admin-guide/kernel-parameters.txt)

description:

    rootflags=      [KNL] Set root filesystem mount option string

This patch make it work for tmpfs.

> .