diff options
Diffstat (limited to 'include/linux/compiler.h')
-rw-r--r-- | include/linux/compiler.h | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/include/linux/compiler.h b/include/linux/compiler.h index c8bd2daf95e..8322141ee48 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -190,7 +190,9 @@ extern void __chk_io_ptr(const volatile void __iomem *); * ACCESS_ONCE() in different C statements. * * This macro does absolutely -nothing- to prevent the CPU from reordering, - * merging, or refetching absolutely anything at any time. + * merging, or refetching absolutely anything at any time. Its main intended + * use is to mediate communication between process-level code and irq/NMI + * handlers, all running on the same CPU. */ #define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x)) |