diff options
author | Xiaozhou Liu <liuxiaozhou@bytedance.com> | 2018-12-14 22:14:31 +0800 |
---|---|---|
committer | Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> | 2018-12-14 16:57:16 +0100 |
commit | 71391bdd2e9aab188f86bf1ecd9b232531ec7eea (patch) | |
tree | dfdbb33056f1f9beee580d4bcd0d5a5e7bef0aef /include | |
parent | 40e020c129cfc991e8ab4736d2665351ffd1468d (diff) |
include/linux/compiler_types.h: don't pollute userspace with macro definitions
Macros 'inline' and '__gnu_inline' used to be defined in compiler-gcc.h,
which was (and is) included entirely in (__KERNEL__ && !__ASSEMBLY__).
Commit 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually
exclusive") had those macros exposed to userspace, unintentionally.
Then commit a3f8a30f3f00 ("Compiler Attributes: use feature checks
instead of version checks") moved '__gnu_inline' back into
(__KERNEL__ && !__ASSEMBLY__) and 'inline' was left behind. Since 'inline'
depends on '__gnu_inline', compiling error showing "unknown type name
‘__gnu_inline’" will pop up, if userspace somehow includes
<linux/compiler.h>.
Other macros like __must_check, notrace, etc. are in a similar situation.
So just move all these macros back into (__KERNEL__ && !__ASSEMBLY__).
Note:
1. This patch only affects what userspace sees.
2. __must_check (when !CONFIG_ENABLE_MUST_CHECK) and noinline_for_stack
were once defined in __KERNEL__ only, but we believe that they can
be put into !__ASSEMBLY__ too.
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Xiaozhou Liu <liuxiaozhou@bytedance.com>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/compiler_types.h | 108 |
1 files changed, 54 insertions, 54 deletions
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h index 4a3f9c09c92d..ba814f18cb4c 100644 --- a/include/linux/compiler_types.h +++ b/include/linux/compiler_types.h @@ -104,6 +104,60 @@ struct ftrace_likely_data { unsigned long constant; }; +#ifdef CONFIG_ENABLE_MUST_CHECK +#define __must_check __attribute__((__warn_unused_result__)) +#else +#define __must_check +#endif + +#if defined(CC_USING_HOTPATCH) +#define notrace __attribute__((hotpatch(0, 0))) +#else +#define notrace __attribute__((__no_instrument_function__)) +#endif + +/* + * it doesn't make sense on ARM (currently the only user of __naked) + * to trace naked functions because then mcount is called without + * stack and frame pointer being set up and there is no chance to + * restore the lr register to the value before mcount was called. + */ +#define __naked __attribute__((__naked__)) notrace + +#define __compiler_offsetof(a, b) __builtin_offsetof(a, b) + +/* + * Force always-inline if the user requests it so via the .config. + * GCC does not warn about unused static inline functions for + * -Wunused-function. This turns out to avoid the need for complex #ifdef + * directives. Suppress the warning in clang as well by using "unused" + * function attribute, which is redundant but not harmful for gcc. + * Prefer gnu_inline, so that extern inline functions do not emit an + * externally visible function. This makes extern inline behave as per gnu89 + * semantics rather than c99. This prevents multiple symbol definition errors + * of extern inline functions at link time. + * A lot of inline functions can cause havoc with function tracing. + * Do not use __always_inline here, since currently it expands to inline again + * (which would break users of __always_inline). + */ +#if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \ + !defined(CONFIG_OPTIMIZE_INLINING) +#define inline inline __attribute__((__always_inline__)) __gnu_inline \ + __maybe_unused notrace +#else +#define inline inline __gnu_inline \ + __maybe_unused notrace +#endif + +#define __inline__ inline +#define __inline inline + +/* + * Rather then using noinline to prevent stack consumption, use + * noinline_for_stack instead. For documentation reasons. + */ +#define noinline_for_stack noinline + #endif /* __KERNEL__ */ #endif /* __ASSEMBLY__ */ @@ -161,58 +215,4 @@ struct ftrace_likely_data { #define __diag_error(compiler, version, option, comment) \ __diag_ ## compiler(version, error, option) -#ifdef CONFIG_ENABLE_MUST_CHECK -#define __must_check __attribute__((__warn_unused_result__)) -#else -#define __must_check -#endif - -#if defined(CC_USING_HOTPATCH) -#define notrace __attribute__((hotpatch(0, 0))) -#else -#define notrace __attribute__((__no_instrument_function__)) -#endif - -/* - * it doesn't make sense on ARM (currently the only user of __naked) - * to trace naked functions because then mcount is called without - * stack and frame pointer being set up and there is no chance to - * restore the lr register to the value before mcount was called. - */ -#define __naked __attribute__((__naked__)) notrace - -#define __compiler_offsetof(a, b) __builtin_offsetof(a, b) - -/* - * Force always-inline if the user requests it so via the .config. - * GCC does not warn about unused static inline functions for - * -Wunused-function. This turns out to avoid the need for complex #ifdef - * directives. Suppress the warning in clang as well by using "unused" - * function attribute, which is redundant but not harmful for gcc. - * Prefer gnu_inline, so that extern inline functions do not emit an - * externally visible function. This makes extern inline behave as per gnu89 - * semantics rather than c99. This prevents multiple symbol definition errors - * of extern inline functions at link time. - * A lot of inline functions can cause havoc with function tracing. - * Do not use __always_inline here, since currently it expands to inline again - * (which would break users of __always_inline). - */ -#if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \ - !defined(CONFIG_OPTIMIZE_INLINING) -#define inline inline __attribute__((__always_inline__)) __gnu_inline \ - __maybe_unused notrace -#else -#define inline inline __gnu_inline \ - __maybe_unused notrace -#endif - -#define __inline__ inline -#define __inline inline - -/* - * Rather then using noinline to prevent stack consumption, use - * noinline_for_stack instead. For documentation reasons. - */ -#define noinline_for_stack noinline - #endif /* __LINUX_COMPILER_TYPES_H */ |