On Tue, Feb 13, 2024 at 12:16 AM Johannes Weiner <hannes@xxxxxxxxxxx> wrote:
>
> The swapaccount deprecation warning is throwing false positives. Since
> we deprecated the knob and defaulted to enabling, the only reports
> we've been getting are from folks that set swapaccount=1. While this
> is a nice affirmation that always-enabling was the right choice, we
> certainly don't want to warn when users request the supported mode.
>
> Only warn when disabling is requested, and clarify the warning.
>
> Fixes: b25806dcd3d5 ("mm: memcontrol: deprecate swapaccounting=0 mode")
> Cc: stable@xxxxxxxxxxxxxxx
> Reported-by: "Jonas Schäfer" <jonas@xxxxxxxxxxxxx>
> Reported-by: Narcis Garcia <debianlists@xxxxxxxxx>
> Suggested-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
> Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Reviewed-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
> ---
> mm/memcontrol.c | 10 +++++++---
> 1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 1ed40f9d3a27..107ec5d36819 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -7971,9 +7971,13 @@ bool mem_cgroup_swap_full(struct folio *folio)
>
> static int __init setup_swap_account(char *s)
> {
> - pr_warn_once("The swapaccount= commandline option is deprecated. "
> - "Please report your usecase to linux-mm@xxxxxxxxx if you "
> - "depend on this functionality.\n");
> + bool res;
> +
> + if (!kstrtobool(s, &res) && !res)
> + pr_warn_once("The swapaccount=0 commdandline option is deprecated "
> + "in favor of configuring swap control via cgroupfs. "
> + "Please report your usecase to linux-mm@xxxxxxxxx if you "
> + "depend on this functionality.\n");
This line is surely getting long, but I see other similar instances so
I guess that's okay.
> return 1;
> }
> __setup("swapaccount=", setup_swap_account);
> --
> 2.43.0
>
