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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. >> >> Yes, the moved branch will be optimized by the compiler if CONFIG_PAGE_POISONING is >> not set. But for a reader, he can simply skip over that moved branch when >> CONFIG_PAGE_POISONING is not set. > > Saving one branch at init does not justify the churn and reduced > readability. OK, I got it. > >>>> Signed-off-by: Zhen Lei >>>> --- >>>> 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 >>>> >>> >> >> -- >> Regards, >> Zhen Lei >> > -- Regards, Zhen Lei