diff options
Diffstat (limited to 'include/linux/compiler.h')
| -rw-r--r-- | include/linux/compiler.h | 53 |
1 files changed, 31 insertions, 22 deletions
diff --git a/include/linux/compiler.h b/include/linux/compiler.h index 33d3a2e5abab..30827f82ad62 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -250,6 +250,27 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val, */ #include <asm/barrier.h> #include <linux/kasan-checks.h> +#include <linux/kcsan-checks.h> + +/** + * data_race - mark an expression as containing intentional data races + * + * This data_race() macro is useful for situations in which data races + * should be forgiven. One example is diagnostic code that accesses + * shared variables but is not a part of the core synchronization design. + * + * This macro *does not* affect normal code generation, but is a hint + * to tooling that data races here are to be ignored. + */ +#define data_race(expr) \ +({ \ + __unqual_scalar_typeof(({ expr; })) __v = ({ \ + __kcsan_disable_current(); \ + expr; \ + }); \ + __kcsan_enable_current(); \ + __v; \ +}) /* * Use __READ_ONCE() instead of READ_ONCE() if you do not require any @@ -271,30 +292,18 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val, __READ_ONCE_SCALAR(x); \ }) -#define __WRITE_ONCE(x, val) \ -do { \ - *(volatile typeof(x) *)&(x) = (val); \ +#define __WRITE_ONCE(x, val) \ +do { \ + *(volatile typeof(x) *)&(x) = (val); \ } while (0) -#define WRITE_ONCE(x, val) \ -do { \ - compiletime_assert_rwonce_type(x); \ - __WRITE_ONCE(x, val); \ +#define WRITE_ONCE(x, val) \ +do { \ + compiletime_assert_rwonce_type(x); \ + __WRITE_ONCE(x, val); \ } while (0) -#ifdef CONFIG_KASAN -/* - * We can't declare function 'inline' because __no_sanitize_address conflicts - * with inlining. Attempt to inline it may cause a build failure. - * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67368 - * '__maybe_unused' allows us to avoid defined-but-not-used warnings. - */ -# define __no_kasan_or_inline __no_sanitize_address notrace __maybe_unused -#else -# define __no_kasan_or_inline __always_inline -#endif - -static __no_kasan_or_inline +static __no_sanitize_or_inline unsigned long __read_once_word_nocheck(const void *addr) { return __READ_ONCE(*(unsigned long *)addr); @@ -302,8 +311,8 @@ unsigned long __read_once_word_nocheck(const void *addr) /* * Use READ_ONCE_NOCHECK() instead of READ_ONCE() if you need to load a - * word from memory atomically but without telling KASAN. This is usually - * used by unwinding code when walking the stack of a running process. + * word from memory atomically but without telling KASAN/KCSAN. This is + * usually used by unwinding code when walking the stack of a running process. */ #define READ_ONCE_NOCHECK(x) \ ({ \ |