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5044 define static inlines for most often used atomic functions

@@ -34,18 +34,227 @@
 extern "C" {
 #endif
 
 #if !defined(__lint) && defined(__GNUC__)
 
-#if defined(__amd64)
+/*
+ * This file contains a number of static inline functions implementing
+ * various atomic variable functions.  Note that these are *not* all of the
+ * atomic_* functions as defined in usr/src/uts/common/sys/atomic.h.  All
+ * possible atomic_* functions are implemented in usr/src/common/atomic in
+ * pure assembly.  In the absence of an identically named function in this
+ * header file, any use of the function will result in the compiler emitting
+ * a function call as usual.  On the other hand, if an identically named
+ * function exists in this header as a static inline, the compiler will
+ * inline its contents and the linker never sees the symbol reference.  We
+ * use this to avoid implementing some of the more complex and less used
+ * functions and instead falling back to function calls.  Note that in some
+ * cases (e.g., atomic_inc_64) we implement a static inline only on AMD64
+ * but not i386.
+ */
+
+/*
+ * Instruction suffixes for various operand sizes (assuming AMD64)
+ */
+#define SUF_8           "b"
+#define SUF_16          "w"
+#define SUF_32          "l"
+#define SUF_64          "q"
 
+#if defined(__amd64)
+#define SUF_LONG        SUF_64
+#define SUF_PTR         SUF_64
+#define __ATOMIC_OP64(...)      __ATOMIC_OPXX(__VA_ARGS__)
 #elif defined(__i386)
+#define SUF_LONG        SUF_32
+#define SUF_PTR         SUF_32
+#define __ATOMIC_OP64(...)
+#else
+#error "port me"
+#endif
+
+#if defined(__amd64) || defined(__i386)
+
+#define __ATOMIC_OPXX(fxn, type, op)                                    \
+extern __GNU_INLINE void                                                \
+fxn(volatile type *target)                                              \
+{                                                                       \
+        __asm__ __volatile__(                                           \
+            "lock; " op " %0"                                           \
+            : "+m" (*target));                                          \
+}
+
+__ATOMIC_OPXX(atomic_inc_8,      uint8_t,  "inc" SUF_8)
+__ATOMIC_OPXX(atomic_inc_16,     uint16_t, "inc" SUF_16)
+__ATOMIC_OPXX(atomic_inc_32,     uint32_t, "inc" SUF_32)
+__ATOMIC_OP64(atomic_inc_64,     uint64_t, "inc" SUF_64)
+__ATOMIC_OPXX(atomic_inc_uchar,  uchar_t,  "inc" SUF_8)
+__ATOMIC_OPXX(atomic_inc_ushort, ushort_t, "inc" SUF_16)
+__ATOMIC_OPXX(atomic_inc_uint,   uint_t,   "inc" SUF_32)
+__ATOMIC_OPXX(atomic_inc_ulong,  ulong_t,  "inc" SUF_LONG)
+
+__ATOMIC_OPXX(atomic_dec_8,      uint8_t,  "dec" SUF_8)
+__ATOMIC_OPXX(atomic_dec_16,     uint16_t, "dec" SUF_16)
+__ATOMIC_OPXX(atomic_dec_32,     uint32_t, "dec" SUF_32)
+__ATOMIC_OP64(atomic_dec_64,     uint64_t, "dec" SUF_64)
+__ATOMIC_OPXX(atomic_dec_uchar,  uchar_t,  "dec" SUF_8)
+__ATOMIC_OPXX(atomic_dec_ushort, ushort_t, "dec" SUF_16)
+__ATOMIC_OPXX(atomic_dec_uint,   uint_t,   "dec" SUF_32)
+__ATOMIC_OPXX(atomic_dec_ulong,  ulong_t,  "dec" SUF_LONG)
+
+#undef __ATOMIC_OPXX
+
+#define __ATOMIC_OPXX(fxn, type1, type2, op)                            \
+extern __GNU_INLINE void                                                \
+fxn(volatile type1 *target, type2 delta)                                \
+{                                                                       \
+        __asm__ __volatile__(                                           \
+            "lock; " op " %1,%0"                                        \
+            : "+m" (*target)                                            \
+            : "ir" (delta));                                            \
+}
+
+__ATOMIC_OPXX(atomic_add_8,     uint8_t,  int8_t,      "add" SUF_8)
+__ATOMIC_OPXX(atomic_add_16,    uint16_t, int16_t,     "add" SUF_16)
+__ATOMIC_OPXX(atomic_add_32,    uint32_t, int32_t,     "add" SUF_32)
+__ATOMIC_OP64(atomic_add_64,    uint64_t, int64_t,     "add" SUF_64)
+__ATOMIC_OPXX(atomic_add_char,  uchar_t,  signed char, "add" SUF_8)
+__ATOMIC_OPXX(atomic_add_short, ushort_t, short,       "add" SUF_16)
+__ATOMIC_OPXX(atomic_add_int,   uint_t,   int,         "add" SUF_32)
+__ATOMIC_OPXX(atomic_add_long,  ulong_t,  long,        "add" SUF_LONG)
+
+/*
+ * We don't use the above macro here because atomic_add_ptr has an
+ * inconsistent type.  The first argument should really be a 'volatile void
+ * **'.
+ */
+extern __GNU_INLINE void
+atomic_add_ptr(volatile void *target, ssize_t delta)
+{
+        volatile void **tmp = (volatile void **)target;
+
+        __asm__ __volatile__(
+            "lock; add" SUF_PTR " %1,%0"
+            : "+m" (*tmp)
+            : "ir" (delta));
+}
+
+__ATOMIC_OPXX(atomic_or_8,       uint8_t,  uint8_t,  "or" SUF_8)
+__ATOMIC_OPXX(atomic_or_16,      uint16_t, uint16_t, "or" SUF_16)
+__ATOMIC_OPXX(atomic_or_32,      uint32_t, uint32_t, "or" SUF_32)
+__ATOMIC_OP64(atomic_or_64,      uint64_t, uint64_t, "or" SUF_64)
+__ATOMIC_OPXX(atomic_or_uchar,   uchar_t,  uchar_t,  "or" SUF_8)
+__ATOMIC_OPXX(atomic_or_ushort,  ushort_t, ushort_t, "or" SUF_16)
+__ATOMIC_OPXX(atomic_or_uint,    uint_t,   uint_t,   "or" SUF_32)
+__ATOMIC_OPXX(atomic_or_ulong,   ulong_t,  ulong_t,  "or" SUF_LONG)
+
+__ATOMIC_OPXX(atomic_and_8,      uint8_t,  uint8_t,  "and" SUF_8)
+__ATOMIC_OPXX(atomic_and_16,     uint16_t, uint16_t, "and" SUF_16)
+__ATOMIC_OPXX(atomic_and_32,     uint32_t, uint32_t, "and" SUF_32)
+__ATOMIC_OP64(atomic_and_64,     uint64_t, uint64_t, "and" SUF_64)
+__ATOMIC_OPXX(atomic_and_uchar,  uchar_t,  uchar_t,  "and" SUF_8)
+__ATOMIC_OPXX(atomic_and_ushort, ushort_t, ushort_t, "and" SUF_16)
+__ATOMIC_OPXX(atomic_and_uint,   uint_t,   uint_t,   "and" SUF_32)
+__ATOMIC_OPXX(atomic_and_ulong,  ulong_t,  ulong_t,  "and" SUF_LONG)
+
+#undef __ATOMIC_OPXX
+
+#define __ATOMIC_OPXX(fxn, type, op, reg)                               \
+extern __GNU_INLINE type                                                \
+fxn(volatile type *target, type cmp, type new)                          \
+{                                                                       \
+        type ret;                                                       \
+        __asm__ __volatile__(                                           \
+            "lock; " op " %2,%0"                                        \
+            : "+m" (*target), "=a" (ret)                                \
+            : reg (new), "1" (cmp)                                      \
+            : "cc");                                                    \
+        return (ret);                                                   \
+}
+
+__ATOMIC_OPXX(atomic_cas_8,      uint8_t,  "cmpxchg" SUF_8,    "q")
+__ATOMIC_OPXX(atomic_cas_16,     uint16_t, "cmpxchg" SUF_16,   "r")
+__ATOMIC_OPXX(atomic_cas_32,     uint32_t, "cmpxchg" SUF_32,   "r")
+__ATOMIC_OP64(atomic_cas_64,     uint64_t, "cmpxchg" SUF_64,   "r")
+__ATOMIC_OPXX(atomic_cas_uchar,  uchar_t,  "cmpxchg" SUF_8,    "q")
+__ATOMIC_OPXX(atomic_cas_ushort, ushort_t, "cmpxchg" SUF_16,   "r")
+__ATOMIC_OPXX(atomic_cas_uint,   uint_t,   "cmpxchg" SUF_32,   "r")
+__ATOMIC_OPXX(atomic_cas_ulong,  ulong_t,  "cmpxchg" SUF_LONG, "r")
+
+#undef __ATOMIC_OPXX
+
+/*
+ * We don't use the above macro here because atomic_cas_ptr has an
+ * inconsistent type.  The first argument should really be a 'volatile void
+ * **'.
+ */
+extern __GNU_INLINE void *
+atomic_cas_ptr(volatile void *target, void *cmp, void *new)
+{
+        volatile void **tmp = (volatile void **)target;
+        void *ret;
+
+        __asm__ __volatile__(
+            "lock; cmpxchg" SUF_PTR " %2,%0"
+            : "+m" (*tmp), "=a" (ret)
+            : "r" (new), "1" (cmp)
+            : "cc");
+
+        return (ret);
+}
+
+#define __ATOMIC_OPXX(fxn, type, op, reg)                               \
+extern __GNU_INLINE type                                                \
+fxn(volatile type *target, type val)                                    \
+{                                                                       \
+        __asm__ __volatile__(                                           \
+            op " %1,%0"                                                 \
+            : "+m" (*target), "+" reg (val));                           \
+        return (val);                                                   \
+}
+
+__ATOMIC_OPXX(atomic_swap_8,      uint8_t,  "xchg" SUF_8,    "q")
+__ATOMIC_OPXX(atomic_swap_16,     uint16_t, "xchg" SUF_16,   "r")
+__ATOMIC_OPXX(atomic_swap_32,     uint32_t, "xchg" SUF_32,   "r")
+__ATOMIC_OP64(atomic_swap_64,     uint64_t, "xchg" SUF_64,   "r")
+__ATOMIC_OPXX(atomic_swap_uchar,  uchar_t,  "xchg" SUF_8,    "q")
+__ATOMIC_OPXX(atomic_swap_ushort, ushort_t, "xchg" SUF_16,   "r")
+__ATOMIC_OPXX(atomic_swap_uint,   uint_t,   "xchg" SUF_32,   "r")
+__ATOMIC_OPXX(atomic_swap_ulong,  ulong_t,  "xchg" SUF_LONG, "r")
+
+#undef __ATOMIC_OPXX
+
+/*
+ * We don't use the above macro here because atomic_swap_ptr has an
+ * inconsistent type.  The first argument should really be a 'volatile void
+ * **'.
+ */
+extern __GNU_INLINE void *
+atomic_swap_ptr(volatile void *target, void *val)
+{
+        volatile void **tmp = (volatile void **)target;
+
+        __asm__ __volatile__(
+            "xchg" SUF_PTR " %1,%0"
+            : "+m" (*tmp), "+r" (val));
+
+        return (val);
+}
 
 #else
 #error  "port me"
 #endif
 
+#undef SUF_8
+#undef SUF_16
+#undef SUF_32
+#undef SUF_64
+#undef SUF_LONG
+#undef SUF_PTR
+
+#undef __ATOMIC_OP64
+
 #endif /* !__lint && __GNUC__ */
 
 #ifdef __cplusplus
 }
 #endif