On Mon, Oct 28, 2024 at 1:58 AM Maíra Canal <mcanal@xxxxxxxxxx> wrote:
>
> If we add ``thp_anon=32,64KB:always`` to the kernel command line, we
> will see the following error:
>
> [ 0.000000] huge_memory: thp_anon=32,64K:always: error parsing string, ignoring setting
>
> This happens because the correct format isn't ``thp_anon=<size>,<size>[KMG]:<state>```,
> as [KMG] must follow each number to especify its unit. So, the correct
> format is ``thp_anon=<size>[KMG],<size>[KMG]:<state>```.
what if 32768,64K: always?
>
> Therefore, adjust the documentation to reflect the correct format of the
> parameter ``thp_anon=``.
>
> Fixes: dd4d30d1cdbe ("mm: override mTHP "enabled" defaults at kernel cmdline")
> Signed-off-by: Maíra Canal <mcanal@xxxxxxxxxx>
> ---
> Documentation/admin-guide/kernel-parameters.txt | 2 +-
> Documentation/admin-guide/mm/transhuge.rst | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> index 1518343bbe22..1666576acc0e 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -6688,7 +6688,7 @@
> 0: no polling (default)
>
> thp_anon= [KNL]
> - Format: <size>,<size>[KMG]:<state>;<size>-<size>[KMG]:<state>
> + Format: <size>[KMG],<size>[KMG]:<state>;<size>[KMG]-<size>[KMG]:<state>
> state is one of "always", "madvise", "never" or "inherit".
> Control the default behavior of the system with respect
> to anonymous transparent hugepages.
> diff --git a/Documentation/admin-guide/mm/transhuge.rst b/Documentation/admin-guide/mm/transhuge.rst
> index 203ba7aaf5fc..745055c3dc09 100644
> --- a/Documentation/admin-guide/mm/transhuge.rst
> +++ b/Documentation/admin-guide/mm/transhuge.rst
> @@ -303,7 +303,7 @@ control by passing the parameter ``transparent_hugepage=always`` or
> kernel command line.
>
> Alternatively, each supported anonymous THP size can be controlled by
> -passing ``thp_anon=<size>,<size>[KMG]:<state>;<size>-<size>[KMG]:<state>``,
> +passing ``thp_anon=<size>[KMG],<size>[KMG]:<state>;<size>[KMG]-<size>[KMG]:<state>``,
> where ``<size>`` is the THP size (must be a power of 2 of PAGE_SIZE and
> supported anonymous THP) and ``<state>`` is one of ``always``, ``madvise``,
> ``never`` or ``inherit``.
> --
> 2.46.2
>
