Right now, the state of CONFIG_INIT_ON_ALLOC_DEFAULT_ON (and
...ON_FREE...) did not change the assembly ordering of the static branch
tests. Use the new jump_label macro to check CONFIG settings to default
to the "expected" state, unpessimizes the resulting assembly code.

Reviewed-by: Alexander Potapenko <gli...@google.com>
Link: 
https://lore.kernel.org/lkml/CAG_fn=x0dvwqlahjto6jw7tgcmsm77gkhinrd0m_6y0szwo...@mail.gmail.com/
Signed-off-by: Kees Cook <keesc...@chromium.org>
---
 include/linux/mm.h | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index bf341a9bfe46..2ccd856ac0d1 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2874,7 +2874,8 @@ static inline void kernel_unpoison_pages(struct page 
*page, int numpages) { }
 DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc);
 static inline bool want_init_on_alloc(gfp_t flags)
 {
-       if (static_branch_unlikely(&init_on_alloc))
+       if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON,
+                               &init_on_alloc))
                return true;
        return flags & __GFP_ZERO;
 }
@@ -2882,7 +2883,8 @@ static inline bool want_init_on_alloc(gfp_t flags)
 DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free);
 static inline bool want_init_on_free(void)
 {
-       return static_branch_unlikely(&init_on_free);
+       return static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON,
+                                  &init_on_free);
 }
 
 extern bool _debug_pagealloc_enabled_early;
-- 
2.25.1

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