[lttng-dev] [PATCH urcu] Fix uatomic sign cast (v2)
Mathieu Desnoyers
mathieu.desnoyers at efficios.com
Tue Mar 20 10:03:36 EDT 2012
Passing an unsigned int to uatomic_sub does not honor sign extend to
long, as we should be allowed by assume.
Fix this by introducing caa_cast_long_keep_sign(), which casts either to
long or unsigned long depending on the signedness of the argument
received. It is used in uatomic_sub before applying the "-" operator,
since this operator needs to operate on the "long" type size (since sign
extension might not be performed if the argument received is unsigned).
Changelog since v1:
- cast_long_keep_sign -> caa_cast_long_keep_sign
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
---
tests/test_uatomic.c | 4 +++
urcu/compiler.h | 5 ++++
urcu/uatomic/generic.h | 59 ++++++++++++++++++++++++++-----------------------
urcu/uatomic/ppc.h | 18 ++++++++------
urcu/uatomic/s390.h | 13 +++++-----
urcu/uatomic/sparc64.h | 7 +++--
urcu/uatomic/x86.h | 42 ++++++++++++++++++----------------
7 files changed, 84 insertions(+), 64 deletions(-)
Index: userspace-rcu/tests/test_uatomic.c
===================================================================
--- userspace-rcu.orig/tests/test_uatomic.c
+++ userspace-rcu/tests/test_uatomic.c
@@ -62,6 +62,10 @@ do { \
assert(uatomic_read(ptr) == 122); \
v = uatomic_sub_return(ptr, 1); \
assert(v == 121); \
+ uatomic_sub(ptr, (unsigned int) 2); \
+ assert(uatomic_read(ptr) == 119); \
+ uatomic_inc(ptr); \
+ uatomic_inc(ptr); \
assert(uatomic_read(ptr) == 121); \
uatomic_and(ptr, 129); \
assert(uatomic_read(ptr) == 1); \
Index: userspace-rcu/urcu/compiler.h
===================================================================
--- userspace-rcu.orig/urcu/compiler.h
+++ userspace-rcu/urcu/compiler.h
@@ -86,4 +86,9 @@
#define URCU_FORCE_CAST(type, arg) ((type) (arg))
#endif
+#define caa_is_signed_type(type) (((type) (-1)) < 0)
+
+#define caa_cast_long_keep_sign(v) \
+ (caa_is_signed_type(__typeof__(v)) ? (long) (v) : (unsigned long) (v))
+
#endif /* _URCU_COMPILER_H */
Index: userspace-rcu/urcu/uatomic/generic.h
===================================================================
--- userspace-rcu.orig/urcu/uatomic/generic.h
+++ userspace-rcu/urcu/uatomic/generic.h
@@ -81,9 +81,10 @@ unsigned long _uatomic_cmpxchg(void *add
}
-#define uatomic_cmpxchg(addr, old, _new) \
- ((__typeof__(*(addr))) _uatomic_cmpxchg((addr), (unsigned long)(old),\
- (unsigned long)(_new), \
+#define uatomic_cmpxchg(addr, old, _new) \
+ ((__typeof__(*(addr))) _uatomic_cmpxchg((addr), \
+ caa_cast_long_keep_sign(old), \
+ caa_cast_long_keep_sign(_new),\
sizeof(*(addr))))
@@ -119,8 +120,8 @@ void _uatomic_and(void *addr, unsigned l
#define uatomic_and(addr, v) \
(_uatomic_and((addr), \
- (unsigned long)(v), \
- sizeof(*(addr))))
+ caa_cast_long_keep_sign(v), \
+ sizeof(*(addr))))
#endif
/* uatomic_or */
@@ -156,8 +157,8 @@ void _uatomic_or(void *addr, unsigned lo
#define uatomic_or(addr, v) \
(_uatomic_or((addr), \
- (unsigned long)(v), \
- sizeof(*(addr))))
+ caa_cast_long_keep_sign(v), \
+ sizeof(*(addr))))
#endif
/* uatomic_add_return */
@@ -188,10 +189,10 @@ unsigned long _uatomic_add_return(void *
}
-#define uatomic_add_return(addr, v) \
- ((__typeof__(*(addr))) _uatomic_add_return((addr), \
- (unsigned long)(v), \
- sizeof(*(addr))))
+#define uatomic_add_return(addr, v) \
+ ((__typeof__(*(addr))) _uatomic_add_return((addr), \
+ caa_cast_long_keep_sign(v), \
+ sizeof(*(addr))))
#endif /* #ifndef uatomic_add_return */
#ifndef uatomic_xchg
@@ -253,7 +254,8 @@ unsigned long _uatomic_exchange(void *ad
}
#define uatomic_xchg(addr, v) \
- ((__typeof__(*(addr))) _uatomic_exchange((addr), (unsigned long)(v), \
+ ((__typeof__(*(addr))) _uatomic_exchange((addr), \
+ caa_cast_long_keep_sign(v), \
sizeof(*(addr))))
#endif /* #ifndef uatomic_xchg */
@@ -322,10 +324,10 @@ void _uatomic_and(void *addr, unsigned l
_uatomic_link_error();
}
-#define uatomic_and(addr, v) \
- (_uatomic_and((addr), \
- (unsigned long)(v), \
- sizeof(*(addr))))
+#define uatomic_and(addr, v) \
+ (_uatomic_and((addr), \
+ caa_cast_long_keep_sign(v), \
+ sizeof(*(addr))))
#endif /* #ifndef uatomic_and */
#ifndef uatomic_or
@@ -393,10 +395,10 @@ void _uatomic_or(void *addr, unsigned lo
_uatomic_link_error();
}
-#define uatomic_or(addr, v) \
- (_uatomic_or((addr), \
- (unsigned long)(v),\
- sizeof(*(addr))))
+#define uatomic_or(addr, v) \
+ (_uatomic_or((addr), \
+ caa_cast_long_keep_sign(v), \
+ sizeof(*(addr))))
#endif /* #ifndef uatomic_or */
#ifndef uatomic_add_return
@@ -469,10 +471,10 @@ unsigned long _uatomic_add_return(void *
return 0;
}
-#define uatomic_add_return(addr, v) \
- ((__typeof__(*(addr))) _uatomic_add_return((addr), \
- (unsigned long)(v), \
- sizeof(*(addr))))
+#define uatomic_add_return(addr, v) \
+ ((__typeof__(*(addr))) _uatomic_add_return((addr), \
+ caa_cast_long_keep_sign(v), \
+ sizeof(*(addr))))
#endif /* #ifndef uatomic_add_return */
#ifndef uatomic_xchg
@@ -546,7 +548,8 @@ unsigned long _uatomic_exchange(void *ad
}
#define uatomic_xchg(addr, v) \
- ((__typeof__(*(addr))) _uatomic_exchange((addr), (unsigned long)(v), \
+ ((__typeof__(*(addr))) _uatomic_exchange((addr), \
+ caa_cast_long_keep_sign(v), \
sizeof(*(addr))))
#endif /* #ifndef uatomic_xchg */
@@ -558,8 +561,10 @@ unsigned long _uatomic_exchange(void *ad
#define uatomic_add(addr, v) (void)uatomic_add_return((addr), (v))
#endif
-#define uatomic_sub_return(addr, v) uatomic_add_return((addr), -(v))
-#define uatomic_sub(addr, v) uatomic_add((addr), -(v))
+#define uatomic_sub_return(addr, v) \
+ uatomic_add_return((addr), -(caa_cast_long_keep_sign(v)))
+#define uatomic_sub(addr, v) \
+ uatomic_add((addr), -(caa_cast_long_keep_sign(v)))
#ifndef uatomic_inc
#define uatomic_inc(addr) uatomic_add((addr), 1)
Index: userspace-rcu/urcu/uatomic/ppc.h
===================================================================
--- userspace-rcu.orig/urcu/uatomic/ppc.h
+++ userspace-rcu/urcu/uatomic/ppc.h
@@ -100,7 +100,8 @@ unsigned long _uatomic_exchange(void *ad
}
#define uatomic_xchg(addr, v) \
- ((__typeof__(*(addr))) _uatomic_exchange((addr), (unsigned long)(v), \
+ ((__typeof__(*(addr))) _uatomic_exchange((addr), \
+ caa_cast_long_keep_sign(v), \
sizeof(*(addr))))
/* cmpxchg */
@@ -159,9 +160,10 @@ unsigned long _uatomic_cmpxchg(void *add
}
-#define uatomic_cmpxchg(addr, old, _new) \
- ((__typeof__(*(addr))) _uatomic_cmpxchg((addr), (unsigned long)(old),\
- (unsigned long)(_new), \
+#define uatomic_cmpxchg(addr, old, _new) \
+ ((__typeof__(*(addr))) _uatomic_cmpxchg((addr), \
+ caa_cast_long_keep_sign(old), \
+ caa_cast_long_keep_sign(_new),\
sizeof(*(addr))))
/* uatomic_add_return */
@@ -215,10 +217,10 @@ unsigned long _uatomic_add_return(void *
}
-#define uatomic_add_return(addr, v) \
- ((__typeof__(*(addr))) _uatomic_add_return((addr), \
- (unsigned long)(v), \
- sizeof(*(addr))))
+#define uatomic_add_return(addr, v) \
+ ((__typeof__(*(addr))) _uatomic_add_return((addr), \
+ caa_cast_long_keep_sign(v), \
+ sizeof(*(addr))))
#ifdef __cplusplus
}
Index: userspace-rcu/urcu/uatomic/s390.h
===================================================================
--- userspace-rcu.orig/urcu/uatomic/s390.h
+++ userspace-rcu/urcu/uatomic/s390.h
@@ -106,8 +106,9 @@ unsigned long _uatomic_exchange(volatile
}
#define uatomic_xchg(addr, v) \
- (__typeof__(*(addr))) _uatomic_exchange((addr), (unsigned long)(v), \
- sizeof(*(addr)))
+ (__typeof__(*(addr))) _uatomic_exchange((addr), \
+ caa_cast_long_keep_sign(v), \
+ sizeof(*(addr)))
/* cmpxchg */
@@ -145,10 +146,10 @@ unsigned long _uatomic_cmpxchg(void *add
return 0;
}
-#define uatomic_cmpxchg(addr, old, _new) \
- (__typeof__(*(addr))) _uatomic_cmpxchg((addr), \
- (unsigned long)(old), \
- (unsigned long)(_new), \
+#define uatomic_cmpxchg(addr, old, _new) \
+ (__typeof__(*(addr))) _uatomic_cmpxchg((addr), \
+ caa_cast_long_keep_sign(old), \
+ caa_cast_long_keep_sign(_new),\
sizeof(*(addr)))
#ifdef __cplusplus
Index: userspace-rcu/urcu/uatomic/sparc64.h
===================================================================
--- userspace-rcu.orig/urcu/uatomic/sparc64.h
+++ userspace-rcu/urcu/uatomic/sparc64.h
@@ -66,9 +66,10 @@ unsigned long _uatomic_cmpxchg(void *add
}
-#define uatomic_cmpxchg(addr, old, _new) \
- ((__typeof__(*(addr))) _uatomic_cmpxchg((addr), (unsigned long)(old),\
- (unsigned long)(_new), \
+#define uatomic_cmpxchg(addr, old, _new) \
+ ((__typeof__(*(addr))) _uatomic_cmpxchg((addr), \
+ caa_cast_long_keep_sign(old), \
+ caa_cast_long_keep_sign(_new), \
sizeof(*(addr))))
#ifdef __cplusplus
Index: userspace-rcu/urcu/uatomic/x86.h
===================================================================
--- userspace-rcu.orig/urcu/uatomic/x86.h
+++ userspace-rcu/urcu/uatomic/x86.h
@@ -102,8 +102,9 @@ unsigned long __uatomic_cmpxchg(void *ad
}
#define _uatomic_cmpxchg(addr, old, _new) \
- ((__typeof__(*(addr))) __uatomic_cmpxchg((addr), (unsigned long)(old),\
- (unsigned long)(_new), \
+ ((__typeof__(*(addr))) __uatomic_cmpxchg((addr), \
+ caa_cast_long_keep_sign(old), \
+ caa_cast_long_keep_sign(_new),\
sizeof(*(addr))))
/* xchg */
@@ -163,7 +164,8 @@ unsigned long __uatomic_exchange(void *a
}
#define _uatomic_xchg(addr, v) \
- ((__typeof__(*(addr))) __uatomic_exchange((addr), (unsigned long)(v), \
+ ((__typeof__(*(addr))) __uatomic_exchange((addr), \
+ caa_cast_long_keep_sign(v), \
sizeof(*(addr))))
/* uatomic_add_return */
@@ -226,10 +228,10 @@ unsigned long __uatomic_add_return(void
return 0;
}
-#define _uatomic_add_return(addr, v) \
- ((__typeof__(*(addr))) __uatomic_add_return((addr), \
- (unsigned long)(v), \
- sizeof(*(addr))))
+#define _uatomic_add_return(addr, v) \
+ ((__typeof__(*(addr))) __uatomic_add_return((addr), \
+ caa_cast_long_keep_sign(v), \
+ sizeof(*(addr))))
/* uatomic_and */
@@ -283,7 +285,7 @@ void __uatomic_and(void *addr, unsigned
}
#define _uatomic_and(addr, v) \
- (__uatomic_and((addr), (unsigned long)(v), sizeof(*(addr))))
+ (__uatomic_and((addr), caa_cast_long_keep_sign(v), sizeof(*(addr))))
/* uatomic_or */
@@ -337,7 +339,7 @@ void __uatomic_or(void *addr, unsigned l
}
#define _uatomic_or(addr, v) \
- (__uatomic_or((addr), (unsigned long)(v), sizeof(*(addr))))
+ (__uatomic_or((addr), caa_cast_long_keep_sign(v), sizeof(*(addr))))
/* uatomic_add */
@@ -391,7 +393,7 @@ void __uatomic_add(void *addr, unsigned
}
#define _uatomic_add(addr, v) \
- (__uatomic_add((addr), (unsigned long)(v), sizeof(*(addr))))
+ (__uatomic_add((addr), caa_cast_long_keep_sign(v), sizeof(*(addr))))
/* uatomic_inc */
@@ -517,7 +519,7 @@ extern unsigned long _compat_uatomic_set
unsigned long _new, int len);
#define compat_uatomic_set(addr, _new) \
((__typeof__(*(addr))) _compat_uatomic_set((addr), \
- (unsigned long)(_new), \
+ caa_cast_long_keep_sign(_new), \
sizeof(*(addr))))
@@ -525,35 +527,35 @@ extern unsigned long _compat_uatomic_xch
unsigned long _new, int len);
#define compat_uatomic_xchg(addr, _new) \
((__typeof__(*(addr))) _compat_uatomic_xchg((addr), \
- (unsigned long)(_new), \
+ caa_cast_long_keep_sign(_new), \
sizeof(*(addr))))
extern unsigned long _compat_uatomic_cmpxchg(void *addr, unsigned long old,
unsigned long _new, int len);
#define compat_uatomic_cmpxchg(addr, old, _new) \
((__typeof__(*(addr))) _compat_uatomic_cmpxchg((addr), \
- (unsigned long)(old), \
- (unsigned long)(_new), \
+ caa_cast_long_keep_sign(old), \
+ caa_cast_long_keep_sign(_new), \
sizeof(*(addr))))
extern void _compat_uatomic_and(void *addr, unsigned long _new, int len);
#define compat_uatomic_and(addr, v) \
(_compat_uatomic_and((addr), \
- (unsigned long)(v), \
+ caa_cast_long_keep_sign(v), \
sizeof(*(addr))))
extern void _compat_uatomic_or(void *addr, unsigned long _new, int len);
#define compat_uatomic_or(addr, v) \
(_compat_uatomic_or((addr), \
- (unsigned long)(v), \
+ caa_cast_long_keep_sign(v), \
sizeof(*(addr))))
extern unsigned long _compat_uatomic_add_return(void *addr,
unsigned long _new, int len);
-#define compat_uatomic_add_return(addr, v) \
- ((__typeof__(*(addr))) _compat_uatomic_add_return((addr), \
- (unsigned long)(v), \
- sizeof(*(addr))))
+#define compat_uatomic_add_return(addr, v) \
+ ((__typeof__(*(addr))) _compat_uatomic_add_return((addr), \
+ caa_cast_long_keep_sign(v), \
+ sizeof(*(addr))))
#define compat_uatomic_add(addr, v) \
((void)compat_uatomic_add_return((addr), (v)))
--
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com
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