Module Name: src
Committed By: riastradh
Date: Sun Dec 1 15:28:02 UTC 2019
Modified Files:
src/sys/sys: atomic.h
Log Message:
Rework modified atomic_load/store_* to work on const pointers.
To generate a diff of this commit:
cvs rdiff -u -r1.19 -r1.20 src/sys/sys/atomic.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/sys/atomic.h
diff -u src/sys/sys/atomic.h:1.19 src/sys/sys/atomic.h:1.20
--- src/sys/sys/atomic.h:1.19 Sun Dec 1 08:15:58 2019
+++ src/sys/sys/atomic.h Sun Dec 1 15:28:02 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: atomic.h,v 1.19 2019/12/01 08:15:58 maxv Exp $ */
+/* $NetBSD: atomic.h,v 1.20 2019/12/01 15:28:02 riastradh Exp $ */
/*-
* Copyright (c) 2007, 2008 The NetBSD Foundation, Inc.
@@ -414,13 +414,18 @@ __END_DECLS
#ifdef KCSAN
void kcsan_atomic_load(const volatile void *, void *, int);
void kcsan_atomic_store(volatile void *, const void *, int);
-#define __DO_ATOMIC_LOAD(p, v) \
- kcsan_atomic_load(p, __UNVOLATILE(&v), sizeof(v))
+#define __BEGIN_ATOMIC_LOAD(p, v) \
+ union { __typeof__(*(p)) __al_val; char __al_buf[1]; } v; \
+ kcsan_atomic_load(p, v.__al_buf, sizeof(v.__al_val))
+#define __END_ATOMIC_LOAD(v) \
+ (v).__al_val
#define __DO_ATOMIC_STORE(p, v) \
kcsan_atomic_store(p, __UNVOLATILE(&v), sizeof(v))
#else
-#define __DO_ATOMIC_LOAD(p, v) \
- v = *p
+#define __BEGIN_ATOMIC_LOAD(p, v) \
+ __typeof__(*(p)) v = *(p)
+#define __END_ATOMIC_LOAD(v) \
+ v
#define __DO_ATOMIC_STORE(p, v) \
*p = v
#endif
@@ -428,20 +433,18 @@ void kcsan_atomic_store(volatile void *,
#define atomic_load_relaxed(p) \
({ \
const volatile __typeof__(*(p)) *__al_ptr = (p); \
- __typeof__(*(p)) __al_val; \
__ATOMIC_PTR_CHECK(__al_ptr); \
- __DO_ATOMIC_LOAD(__al_ptr, __al_val); \
- __al_val; \
+ __BEGIN_ATOMIC_LOAD(__al_ptr, __al_val); \
+ __END_ATOMIC_LOAD(__al_val); \
})
#define atomic_load_consume(p) \
({ \
const volatile __typeof__(*(p)) *__al_ptr = (p); \
- __typeof__(*(p)) __al_val; \
__ATOMIC_PTR_CHECK(__al_ptr); \
- __DO_ATOMIC_LOAD(__al_ptr, __al_val); \
+ __BEGIN_ATOMIC_LOAD(__al_ptr, __al_val); \
membar_datadep_consumer(); \
- __al_val; \
+ __END_ATOMIC_LOAD(__al_val); \
})
/*
@@ -453,11 +456,10 @@ void kcsan_atomic_store(volatile void *,
#define atomic_load_acquire(p) \
({ \
const volatile __typeof__(*(p)) *__al_ptr = (p); \
- __typeof__(*(p)) __al_val; \
__ATOMIC_PTR_CHECK(__al_ptr); \
- __DO_ATOMIC_LOAD(__al_ptr, __al_val); \
+ __BEGIN_ATOMIC_LOAD(__al_ptr, __al_val); \
membar_sync(); \
- __al_val; \
+ __END_ATOMIC_LOAD(__al_val); \
})
#define atomic_store_relaxed(p,v) \
