Commit e5fc436f authored Aug 28, 2020 by Luc Van Oostenryck Committed by Miguel Ojeda Aug 29, 2020

sparse: use static inline for __chk_{user,io}_ptr()



__chk_user_ptr() & __chk_io_ptr() are dummy extern functions which
only exist to enforce the typechecking of __user or __iomem pointers
in macros when using sparse.

This typechecking is done by inserting a call to these functions.
But the presence of these calls can inhibit some simplifications
and so influence the result of sparse's analysis of context/locking.

Fix this by changing these calls into static inline calls with
an empty body.

Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>

parent 5861af92

include/linux/compiler_types.h

+2 −2

Original line number	Diff line number	Diff line
		@@ -11,8 +11,8 @@
		# define __iomem __attribute__((noderef, address_space(__iomem)))
		# define __percpu __attribute__((noderef, address_space(__percpu)))
		# define __rcu __attribute__((noderef, address_space(__rcu)))
		extern void __chk_user_ptr(const volatile void __user *);
		extern void __chk_io_ptr(const volatile void __iomem *);
		static inline void __chk_user_ptr(const volatile void __user *ptr) { }
		static inline void __chk_io_ptr(const volatile void __iomem *ptr) { }
		/* context/locking */
		# define __must_hold(x) __attribute__((context(x,1,1)))
		# define __acquires(x) __attribute__((context(x,0,1)))

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