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

[chenweilong <chenweilong@huawei.com>]

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@huawei.com>
>> ---
>>  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.

> .