On 5/5/20 3:16 PM, Thomas Gleixner wrote:
READ/WRITE_ONCE_NOCHECK() is required for atomics in code which cannot be
instrumented like the x86 int3 text poke code. As READ/WRITE_ONCE() is
undergoing a rewrite, provide __{READ,WRITE}_ONCE_SCALAR().
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
---
include/linux/compiler.h | 8 ++++++++
1 file changed, 8 insertions(+)
Reviewed-by: Alexandre Chartre <[email protected]>
alex.
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -313,6 +313,14 @@ unsigned long read_word_at_a_time(const
__u.__val; \
})
+#define __READ_ONCE_SCALAR(x) \
+ (*(const volatile typeof(x) *)&(x))
+
+#define __WRITE_ONCE_SCALAR(x, val) \
+do { \
+ *(volatile typeof(x) *)&(x) = val; \
+} while (0)
+
/**
* data_race - mark an expression as containing intentional data races
*
