From: David Laight <david.laight.linux@gmail.com>
Replace the:
*reg &= ~mask; *reg |= new_value;
with a single assignment.
While the compiler will usually optimise the extra access away
it isn't guaranteed.
Signed-off-by: David Laight <david.laight.linux@gmail.com>
---
include/linux/bitfield.h | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/include/linux/bitfield.h b/include/linux/bitfield.h
index f1859e28df5d..c354ca2ef1a0 100644
--- a/include/linux/bitfield.h
+++ b/include/linux/bitfield.h
@@ -200,8 +200,7 @@
__auto_type _val = 1 ? (val) : _mask; \
typecheck_pointer(_reg_p); \
__BF_FIELD_CHECK(_mask, *(_reg_p), _val, "FIELD_MODIFY: "); \
- *(_reg_p) &= ~(_mask); \
- *(_reg_p) |= (_val << __bf_shf(_mask)) & _mask; \
+ *_reg_p = (*_reg_p & ~_mask) | ((_val << __bf_shf(_mask)) & _mask); \
})
extern void __compiletime_error("value doesn't fit into mask")
--
2.39.5