diff options
author | Russell King <rmk+kernel@armlinux.org.uk> | 2016-10-06 08:56:43 +0100 |
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committer | Russell King <rmk+kernel@armlinux.org.uk> | 2016-10-06 08:56:43 +0100 |
commit | 301a36fa700f9add6e14f5a95c7573e01578343a (patch) | |
tree | 6ff94ff3b08b838353b9127eb5f8055b3de6b25f /include/linux/compiler.h | |
parent | b828f960215f02e5d2c88bbd27565c694254a15a (diff) | |
parent | b60752f2b20c167859943e001727f0d4da419b23 (diff) |
Merge branches 'misc' and 'sa1111-base' into for-linus
Diffstat (limited to 'include/linux/compiler.h')
-rw-r--r-- | include/linux/compiler.h | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/include/linux/compiler.h b/include/linux/compiler.h index 1bb954842725..668569844d37 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -527,13 +527,14 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s * object's lifetime is managed by something other than RCU. That * "something other" might be reference counting or simple immortality. * - * The seemingly unused void * variable is to validate @p is indeed a pointer - * type. All pointer types silently cast to void *. + * The seemingly unused variable ___typecheck_p validates that @p is + * indeed a pointer type by using a pointer to typeof(*p) as the type. + * Taking a pointer to typeof(*p) again is needed in case p is void *. */ #define lockless_dereference(p) \ ({ \ typeof(p) _________p1 = READ_ONCE(p); \ - __maybe_unused const void * const _________p2 = _________p1; \ + typeof(*(p)) *___typecheck_p __maybe_unused; \ smp_read_barrier_depends(); /* Dependency order vs. p above. */ \ (_________p1); \ }) |