[ltt-dev] [PATCH 04/10] uatomic: add uatomic_or

[pbonzini@redhat.com (Paolo Bonzini)]

For now, only the version returning void is used.  Also, I am not
providing PPC versions because I would be unable to test it right
now.

Signed-off-by: Paolo Bonzini <pbonzini at redhat.com>
---
 compat_arch_x86.c       |   25 ++++++++++++
 tests/test_uatomic.c    |    6 ++-
 urcu/uatomic_arch_x86.h |   63 ++++++++++++++++++++++++++++++
 urcu/uatomic_generic.h  |   97 +++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 189 insertions(+), 2 deletions(-)

diff --git a/compat_arch_x86.c b/compat_arch_x86.c
index 5342c7b..33bf13d 100644
--- a/compat_arch_x86.c
+++ b/compat_arch_x86.c
@@ -201,6 +201,31 @@ unsigned long _compat_uatomic_cmpxchg(void *addr, unsigned long old,
 	return retval;
 }
 
+void _compat_uatomic_or(void *addr, unsigned long v, int len)
+{
+	sigset_t mask;
+
+	mutex_lock_signal_save(&compat_mutex, &mask);
+	switch (len) {
+	case 1:
+		*(unsigned char *)addr |= (unsigned char)v;
+		break;
+	case 2:
+		*(unsigned short *)addr |= (unsigned short)v;
+		break;
+	case 4:
+		*(unsigned int *)addr |= (unsigned int)v;
+		break;
+	default:
+		/*
+		 * generate an illegal instruction. Cannot catch this with
+		 * linker tricks when optimizations are disabled.
+		 */
+		__asm__ __volatile__("ud2");
+	}
+	mutex_lock_signal_restore(&compat_mutex, &mask);
+}
+
 unsigned long _compat_uatomic_add_return(void *addr, unsigned long v, int len)
 {
 	sigset_t mask;
diff --git a/tests/test_uatomic.c b/tests/test_uatomic.c
index 5682655..37f95a6 100644
--- a/tests/test_uatomic.c
+++ b/tests/test_uatomic.c
@@ -33,8 +33,10 @@ do {						\
 	assert(uatomic_read(ptr) == 23);		\
 	uatomic_dec(ptr);			\
 	assert(uatomic_read(ptr) == 22);		\
-	v = uatomic_add_return(ptr, 100);	\
-	assert(v == 122);			\
+	v = uatomic_add_return(ptr, 74);	\
+	assert(v == 96);			\
+	assert(uatomic_read(ptr) == 96);	\
+	uatomic_or(ptr, 58);			\
 	assert(uatomic_read(ptr) == 122);	\
 	v = uatomic_sub_return(ptr, 1);		\
 	assert(v == 121);			\
diff --git a/urcu/uatomic_arch_x86.h b/urcu/uatomic_arch_x86.h
index 30418c8..c3b5333 100644
--- a/urcu/uatomic_arch_x86.h
+++ b/urcu/uatomic_arch_x86.h
@@ -231,6 +231,60 @@ unsigned long __uatomic_add_return(void *addr, unsigned long val,
 						  (unsigned long)(v),	\
 						  sizeof(*(addr))))
 
+/* uatomic_or */
+
+static inline __attribute__((always_inline))
+void __uatomic_or(void *addr, unsigned long val, int len)
+{
+	switch (len) {
+	case 1:
+	{
+		__asm__ __volatile__(
+		"lock; orb %1, %0"
+			: "=m"(*__hp(addr))
+			: "iq" ((unsigned char)val)
+			: "memory");
+		return;
+	}
+	case 2:
+	{
+		__asm__ __volatile__(
+		"lock; orw %1, %0"
+			: "=m"(*__hp(addr))
+			: "ir" ((unsigned short)val)
+			: "memory");
+		return;
+	}
+	case 4:
+	{
+		__asm__ __volatile__(
+		"lock; orl %1, %0"
+			: "=m"(*__hp(addr))
+			: "ir" ((unsigned int)val)
+			: "memory");
+		return;
+	}
+#if (CAA_BITS_PER_LONG == 64)
+	case 8:
+	{
+		__asm__ __volatile__(
+		"lock; orq %1, %0"
+			: "=m"(*__hp(addr))
+			: "er" ((unsigned long)val)
+			: "memory");
+		return;
+	}
+#endif
+	}
+	/* generate an illegal instruction. Cannot catch this with linker tricks
+	 * when optimizations are disabled. */
+	__asm__ __volatile__("ud2");
+	return;
+}
+
+#define _uatomic_or(addr, v)						   \
+	(__uatomic_or((addr), (unsigned long)(v), sizeof(*(addr))))
+
 /* uatomic_add */
 
 static inline __attribute__((always_inline))
@@ -428,6 +482,13 @@ extern unsigned long _compat_uatomic_cmpxchg(void *addr, unsigned long old,
 						(unsigned long)(_new), 	       \
 						sizeof(*(addr))))
 
+extern unsigned long _compat_uatomic_or(void *addr,
+				        unsigned long _new, int len);
+#define compat_uatomic_or(addr, v)				       \
+	((__typeof__(*(addr))) _compat_uatomic_or((addr),	       \
+						  (unsigned long)(v),  \
+						  sizeof(*(addr))))
+
 extern unsigned long _compat_uatomic_add_return(void *addr,
 					        unsigned long _new, int len);
 #define compat_uatomic_add_return(addr, v)				       \
@@ -454,6 +515,8 @@ extern unsigned long _compat_uatomic_add_return(void *addr,
 		UATOMIC_COMPAT(cmpxchg(addr, old, _new))
 #define uatomic_xchg(addr, v)			\
 		UATOMIC_COMPAT(xchg(addr, v))
+#define uatomic_or(addr, v)		\
+		UATOMIC_COMPAT(or(addr, v))
 #define uatomic_add_return(addr, v)		\
 		UATOMIC_COMPAT(add_return(addr, v))
 
diff --git a/urcu/uatomic_generic.h b/urcu/uatomic_generic.h
index 347e73f..556846f 100644
--- a/urcu/uatomic_generic.h
+++ b/urcu/uatomic_generic.h
@@ -87,6 +87,39 @@ unsigned long _uatomic_cmpxchg(void *addr, unsigned long old,
 						sizeof(*(addr))))
 
 
+/* uatomic_or */
+
+#ifndef uatomic_or
+static inline __attribute__((always_inline))
+void _uatomic_or(void *addr, unsigned long val,
+		 int len)
+{
+	switch (len) {
+#ifdef UATOMIC_HAS_ATOMIC_BYTE
+	case 1:
+		__sync_or_and_fetch_1(addr, val);
+#endif
+#ifdef UATOMIC_HAS_ATOMIC_SHORT
+	case 2:
+		__sync_or_and_fetch_2(addr, val);
+#endif
+	case 4:
+		__sync_or_and_fetch_4(addr, val);
+#if (CAA_BITS_PER_LONG == 64)
+	case 8:
+		__sync_or_and_fetch_8(addr, val);
+#endif
+	}
+	_uatomic_link_error();
+	return 0;
+}
+
+#define uatomic_or(addr, v)			\
+	(_uatomic_or((addr),			\
+		     (unsigned long)(v),	\
+		     sizeof(*(addr))))
+#endif
+
 /* uatomic_add_return */
 
 #ifndef uatomic_add_return
@@ -186,6 +219,70 @@ unsigned long _uatomic_exchange(void *addr, unsigned long val, int len)
 
 #else /* #ifndef uatomic_cmpxchg */
 
+#ifndef uatomic_or
+/* uatomic_or */
+
+static inline __attribute__((always_inline))
+void _uatomic_or(void *addr, unsigned long val, int len)
+{
+	switch (len) {
+#ifdef UATOMIC_HAS_ATOMIC_BYTE
+	case 1:
+	{
+		unsigned char old, oldt;
+
+		oldt = uatomic_read((unsigned char *)addr);
+		do {
+			old = oldt;
+			oldt = _uatomic_cmpxchg(addr, old, old | val, 1);
+		} while (oldt != old);
+	}
+#endif
+#ifdef UATOMIC_HAS_ATOMIC_SHORT
+	case 2:
+	{
+		unsigned short old, oldt;
+
+		oldt = uatomic_read((unsigned short *)addr);
+		do {
+			old = oldt;
+			oldt = _uatomic_cmpxchg(addr, old, old | val, 2);
+		} while (oldt != old);
+	}
+#endif
+	case 4:
+	{
+		unsigned int old, oldt;
+
+		oldt = uatomic_read((unsigned int *)addr);
+		do {
+			old = oldt;
+			oldt = _uatomic_cmpxchg(addr, old, old | val, 4);
+		} while (oldt != old);
+	}
+#if (CAA_BITS_PER_LONG == 64)
+	case 8:
+	{
+		unsigned long old, oldt;
+
+		oldt = uatomic_read((unsigned long *)addr);
+		do {
+			old = oldt;
+			oldt = _uatomic_cmpxchg(addr, old, old | val, 8);
+		} while (oldt != old);
+	}
+#endif
+	}
+	_uatomic_link_error();
+	return 0;
+}
+
+#define uatomic_or(addr, v)		\
+	(uatomic_or((addr),		\
+		    (unsigned long)(v),	\
+		    sizeof(*(addr))))
+#endif /* #ifndef uatomic_or */
+
 #ifndef uatomic_add_return
 /* uatomic_add_return */
 
-- 
1.7.4.4