Re: [PATCH 1/1] mm/mm_init.c: eliminate a local variable in mem_debugging_and_hardening_init()
From: Mike Rapoport
Date: Mon Mar 18 2024 - 12:34:51 EST
On Mon, Mar 18, 2024 at 09:57:14PM +0800, thunder.leizhen@xxxxxxxxxxxxxxx wrote:
> From: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
>
> The local variable 'page_poisoning_requested' is assigned true at only
> one point. It can be eliminated by moving the code that depends on it
> to the location where it is assigned true. This also make the moved
> code to be compiled only if CONFIG_PAGE_POISONING is set.
I don't see it as much of an improvement and code readability becomes worse
IMO.
> Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
> ---
> mm/mm_init.c | 17 +++++++----------
> 1 file changed, 7 insertions(+), 10 deletions(-)
>
> diff --git a/mm/mm_init.c b/mm/mm_init.c
> index 549e76af8f82a8e..3eb217130bcb2b5 100644
> --- a/mm/mm_init.c
> +++ b/mm/mm_init.c
> @@ -2614,7 +2614,6 @@ DEFINE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled);
> */
> static void __init mem_debugging_and_hardening_init(void)
> {
> - bool page_poisoning_requested = false;
> bool want_check_pages = false;
>
> #ifdef CONFIG_PAGE_POISONING
> @@ -2626,18 +2625,16 @@ static void __init mem_debugging_and_hardening_init(void)
> (!IS_ENABLED(CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC) &&
> debug_pagealloc_enabled())) {
> static_branch_enable(&_page_poisoning_enabled);
> - page_poisoning_requested = true;
> want_check_pages = true;
> - }
> -#endif
>
> - if ((_init_on_alloc_enabled_early || _init_on_free_enabled_early) &&
> - page_poisoning_requested) {
> - pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, "
> - "will take precedence over init_on_alloc and init_on_free\n");
> - _init_on_alloc_enabled_early = false;
> - _init_on_free_enabled_early = false;
> + if (_init_on_alloc_enabled_early || _init_on_free_enabled_early) {
> + pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, "
> + "will take precedence over init_on_alloc and init_on_free\n");
> + _init_on_alloc_enabled_early = false;
> + _init_on_free_enabled_early = false;
> + }
> }
> +#endif
>
> if (_init_on_alloc_enabled_early) {
> want_check_pages = true;
> --
> 2.34.1
>
--
Sincerely yours,
Mike.