local_t: alpha extension

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 329 insertions, 24 deletions

diff --git a/include/asm-alpha/local.h b/include/asm-alpha/local.h
index 90a510fa358e..6ad3ea696421 100644
--- a/include/asm-alpha/local.h
+++ b/include/asm-alpha/local.h
@@ -4,37 +4,115 @@
 #include <linux/percpu.h>
 #include <asm/atomic.h>
 
-typedef atomic64_t local_t;
+typedef struct
+{
+        atomic_long_t a;
+} local_t;
 
-#define LOCAL_INIT(i)   ATOMIC64_INIT(i)
-#define local_read(v)   atomic64_read(v)
-#define local_set(v,i)  atomic64_set(v,i)
+#define LOCAL_INIT(i)   { ATOMIC_LONG_INIT(i) }
+#define local_read(l)   atomic_long_read(&(l)->a)
+#define local_set(l,i)  atomic_long_set(&(l)->a, (i))
+#define local_inc(l)    atomic_long_inc(&(l)->a)
+#define local_dec(l)    atomic_long_dec(&(l)->a)
+#define local_add(i,l)  atomic_long_add((i),(&(l)->a))
+#define local_sub(i,l)  atomic_long_sub((i),(&(l)->a))
 
-#define local_inc(v)    atomic64_inc(v)
-#define local_dec(v)    atomic64_dec(v)
-#define local_add(i, v) atomic64_add(i, v)
-#define local_sub(i, v) atomic64_sub(i, v)
+static __inline__ long local_add_return(long i, local_t * l)
+{
+        long temp, result;
+        __asm__ __volatile__(
+        "1:     ldq_l %0,%1\n"
+        "       addq %0,%3,%2\n"
+        "       addq %0,%3,%0\n"
+        "       stq_c %0,%1\n"
+        "       beq %0,2f\n"
+        ".subsection 2\n"
+        "2:     br 1b\n"
+        ".previous"
+        :"=&r" (temp), "=m" (l->a.counter), "=&r" (result)
+        :"Ir" (i), "m" (l->a.counter) : "memory");
+        return result;
+}
 
-#define __local_inc(v)          ((v)->counter++)
-#define __local_dec(v)          ((v)->counter++)
-#define __local_add(i,v)        ((v)->counter+=(i))
-#define __local_sub(i,v)        ((v)->counter-=(i))
+static __inline__ long local_sub_return(long i, local_t * l)
+{
+        long temp, result;
+        __asm__ __volatile__(
+        "1:     ldq_l %0,%1\n"
+        "       subq %0,%3,%2\n"
+        "       subq %0,%3,%0\n"
+        "       stq_c %0,%1\n"
+        "       beq %0,2f\n"
+        ".subsection 2\n"
+        "2:     br 1b\n"
+        ".previous"
+        :"=&r" (temp), "=m" (l->a.counter), "=&r" (result)
+        :"Ir" (i), "m" (l->a.counter) : "memory");
+        return result;
+}
+
+#define local_cmpxchg(l, o, n) \
+        (cmpxchg_local(&((l)->a.counter), (o), (n)))
+#define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))
+
+/**
+ * local_add_unless - add unless the number is a given value
+ * @l: pointer of type local_t
+ * @a: the amount to add to l...
+ * @u: ...unless l is equal to u.
+ *
+ * Atomically adds @a to @l, so long as it was not @u.
+ * Returns non-zero if @l was not @u, and zero otherwise.
+ */
+#define local_add_unless(l, a, u)                               \
+({                                                              \
+        long c, old;                                            \
+        c = local_read(l);                                      \
+        for (;;) {                                              \
+                if (unlikely(c == (u)))                         \
+                        break;                                  \
+                old = local_cmpxchg((l), c, c + (a));   \
+                if (likely(old == c))                           \
+                        break;                                  \
+                c = old;                                        \
+        }                                                       \
+        c != (u);                                               \
+})
+#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
+
+#define local_add_negative(a, l) (local_add_return((a), (l)) < 0)
+
+#define local_dec_return(l) local_sub_return(1,(l))
+
+#define local_inc_return(l) local_add_return(1,(l))
+
+#define local_sub_and_test(i,l) (local_sub_return((i), (l)) == 0)
+
+#define local_inc_and_test(l) (local_add_return(1, (l)) == 0)
+
+#define local_dec_and_test(l) (local_sub_return(1, (l)) == 0)
+
+/* Verify if faster than atomic ops */
+#define __local_inc(l)          ((l)->a.counter++)
+#define __local_dec(l)          ((l)->a.counter++)
+#define __local_add(i,l)        ((l)->a.counter+=(i))
+#define __local_sub(i,l)        ((l)->a.counter-=(i))
 
 /* Use these for per-cpu local_t variables: on some archs they are
  * much more efficient than these naive implementations.  Note they take
  * a variable, not an address.
  */
-#define cpu_local_read(v)       local_read(&__get_cpu_var(v))
-#define cpu_local_set(v, i)     local_set(&__get_cpu_var(v), (i))
-
-#define cpu_local_inc(v)        local_inc(&__get_cpu_var(v))
-#define cpu_local_dec(v)        local_dec(&__get_cpu_var(v))
-#define cpu_local_add(i, v)     local_add((i), &__get_cpu_var(v))
-#define cpu_local_sub(i, v)     local_sub((i), &__get_cpu_var(v))
-
-#define __cpu_local_inc(v)      __local_inc(&__get_cpu_var(v))
-#define __cpu_local_dec(v)      __local_dec(&__get_cpu_var(v))
-#define __cpu_local_add(i, v)   __local_add((i), &__get_cpu_var(v))
-#define __cpu_local_sub(i, v)   __local_sub((i), &__get_cpu_var(v))
+#define cpu_local_read(l)       local_read(&__get_cpu_var(l))
+#define cpu_local_set(l, i)     local_set(&__get_cpu_var(l), (i))
+
+#define cpu_local_inc(l)        local_inc(&__get_cpu_var(l))
+#define cpu_local_dec(l)        local_dec(&__get_cpu_var(l))
+#define cpu_local_add(i, l)     local_add((i), &__get_cpu_var(l))
+#define cpu_local_sub(i, l)     local_sub((i), &__get_cpu_var(l))
+
+#define __cpu_local_inc(l)      __local_inc(&__get_cpu_var(l))
+#define __cpu_local_dec(l)      __local_dec(&__get_cpu_var(l))
+#define __cpu_local_add(i, l)   __local_add((i), &__get_cpu_var(l))
+#define __cpu_local_sub(i, l)   __local_sub((i), &__get_cpu_var(l))
 
 #endif /* _ALPHA_LOCAL_H */
diff --git a/include/asm-alpha/system.h b/include/asm-alpha/system.h
index 03e9c0e5ed74..42959c356456 100644
--- a/include/asm-alpha/system.h
+++ b/include/asm-alpha/system.h
@@ -443,6 +443,111 @@ extern void __xchg_called_with_bad_pointer(void);
      (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_, sizeof(*(ptr))); \
   })
 
+static inline unsigned long
+__xchg_u8_local(volatile char *m, unsigned long val)
+{
+        unsigned long ret, tmp, addr64;
+
+        __asm__ __volatile__(
+        "       andnot  %4,7,%3\n"
+        "       insbl   %1,%4,%1\n"
+        "1:     ldq_l   %2,0(%3)\n"
+        "       extbl   %2,%4,%0\n"
+        "       mskbl   %2,%4,%2\n"
+        "       or      %1,%2,%2\n"
+        "       stq_c   %2,0(%3)\n"
+        "       beq     %2,2f\n"
+        ".subsection 2\n"
+        "2:     br      1b\n"
+        ".previous"
+        : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
+        : "r" ((long)m), "1" (val) : "memory");
+
+        return ret;
+}
+
+static inline unsigned long
+__xchg_u16_local(volatile short *m, unsigned long val)
+{
+        unsigned long ret, tmp, addr64;
+
+        __asm__ __volatile__(
+        "       andnot  %4,7,%3\n"
+        "       inswl   %1,%4,%1\n"
+        "1:     ldq_l   %2,0(%3)\n"
+        "       extwl   %2,%4,%0\n"
+        "       mskwl   %2,%4,%2\n"
+        "       or      %1,%2,%2\n"
+        "       stq_c   %2,0(%3)\n"
+        "       beq     %2,2f\n"
+        ".subsection 2\n"
+        "2:     br      1b\n"
+        ".previous"
+        : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
+        : "r" ((long)m), "1" (val) : "memory");
+
+        return ret;
+}
+
+static inline unsigned long
+__xchg_u32_local(volatile int *m, unsigned long val)
+{
+        unsigned long dummy;
+
+        __asm__ __volatile__(
+        "1:     ldl_l %0,%4\n"
+        "       bis $31,%3,%1\n"
+        "       stl_c %1,%2\n"
+        "       beq %1,2f\n"
+        ".subsection 2\n"
+        "2:     br 1b\n"
+        ".previous"
+        : "=&r" (val), "=&r" (dummy), "=m" (*m)
+        : "rI" (val), "m" (*m) : "memory");
+
+        return val;
+}
+
+static inline unsigned long
+__xchg_u64_local(volatile long *m, unsigned long val)
+{
+        unsigned long dummy;
+
+        __asm__ __volatile__(
+        "1:     ldq_l %0,%4\n"
+        "       bis $31,%3,%1\n"
+        "       stq_c %1,%2\n"
+        "       beq %1,2f\n"
+        ".subsection 2\n"
+        "2:     br 1b\n"
+        ".previous"
+        : "=&r" (val), "=&r" (dummy), "=m" (*m)
+        : "rI" (val), "m" (*m) : "memory");
+
+        return val;
+}
+
+#define __xchg_local(ptr, x, size) \
+({ \
+        unsigned long __xchg__res; \
+        volatile void *__xchg__ptr = (ptr); \
+        switch (size) { \
+                case 1: __xchg__res = __xchg_u8_local(__xchg__ptr, x); break; \
+                case 2: __xchg__res = __xchg_u16_local(__xchg__ptr, x); break; \
+                case 4: __xchg__res = __xchg_u32_local(__xchg__ptr, x); break; \
+                case 8: __xchg__res = __xchg_u64_local(__xchg__ptr, x); break; \
+                default: __xchg_called_with_bad_pointer(); __xchg__res = x; \
+        } \
+        __xchg__res; \
+})
+
+#define xchg_local(ptr,x)                                                    \
+  ({                                                                         \
+     __typeof__(*(ptr)) _x_ = (x);                                           \
+     (__typeof__(*(ptr))) __xchg_local((ptr), (unsigned long)_x_,            \
+                sizeof(*(ptr))); \
+  })
+
 #define tas(ptr) (xchg((ptr),1))
 
 
@@ -596,6 +701,128 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
                                     (unsigned long)_n_, sizeof(*(ptr))); \
   })
 
+static inline unsigned long
+__cmpxchg_u8_local(volatile char *m, long old, long new)
+{
+        unsigned long prev, tmp, cmp, addr64;
+
+        __asm__ __volatile__(
+        "       andnot  %5,7,%4\n"
+        "       insbl   %1,%5,%1\n"
+        "1:     ldq_l   %2,0(%4)\n"
+        "       extbl   %2,%5,%0\n"
+        "       cmpeq   %0,%6,%3\n"
+        "       beq     %3,2f\n"
+        "       mskbl   %2,%5,%2\n"
+        "       or      %1,%2,%2\n"
+        "       stq_c   %2,0(%4)\n"
+        "       beq     %2,3f\n"
+        "2:\n"
+        ".subsection 2\n"
+        "3:     br      1b\n"
+        ".previous"
+        : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
+        : "r" ((long)m), "Ir" (old), "1" (new) : "memory");
+
+        return prev;
+}
+
+static inline unsigned long
+__cmpxchg_u16_local(volatile short *m, long old, long new)
+{
+        unsigned long prev, tmp, cmp, addr64;
+
+        __asm__ __volatile__(
+        "       andnot  %5,7,%4\n"
+        "       inswl   %1,%5,%1\n"
+        "1:     ldq_l   %2,0(%4)\n"
+        "       extwl   %2,%5,%0\n"
+        "       cmpeq   %0,%6,%3\n"
+        "       beq     %3,2f\n"
+        "       mskwl   %2,%5,%2\n"
+        "       or      %1,%2,%2\n"
+        "       stq_c   %2,0(%4)\n"
+        "       beq     %2,3f\n"
+        "2:\n"
+        ".subsection 2\n"
+        "3:     br      1b\n"
+        ".previous"
+        : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
+        : "r" ((long)m), "Ir" (old), "1" (new) : "memory");
+
+        return prev;
+}
+
+static inline unsigned long
+__cmpxchg_u32_local(volatile int *m, int old, int new)
+{
+        unsigned long prev, cmp;
+
+        __asm__ __volatile__(
+        "1:     ldl_l %0,%5\n"
+        "       cmpeq %0,%3,%1\n"
+        "       beq %1,2f\n"
+        "       mov %4,%1\n"
+        "       stl_c %1,%2\n"
+        "       beq %1,3f\n"
+        "2:\n"
+        ".subsection 2\n"
+        "3:     br 1b\n"
+        ".previous"
+        : "=&r"(prev), "=&r"(cmp), "=m"(*m)
+        : "r"((long) old), "r"(new), "m"(*m) : "memory");
+
+        return prev;
+}
+
+static inline unsigned long
+__cmpxchg_u64_local(volatile long *m, unsigned long old, unsigned long new)
+{
+        unsigned long prev, cmp;
+
+        __asm__ __volatile__(
+        "1:     ldq_l %0,%5\n"
+        "       cmpeq %0,%3,%1\n"
+        "       beq %1,2f\n"
+        "       mov %4,%1\n"
+        "       stq_c %1,%2\n"
+        "       beq %1,3f\n"
+        "2:\n"
+        ".subsection 2\n"
+        "3:     br 1b\n"
+        ".previous"
+        : "=&r"(prev), "=&r"(cmp), "=m"(*m)
+        : "r"((long) old), "r"(new), "m"(*m) : "memory");
+
+        return prev;
+}
+
+static __always_inline unsigned long
+__cmpxchg_local(volatile void *ptr, unsigned long old, unsigned long new,
+                int size)
+{
+        switch (size) {
+                case 1:
+                        return __cmpxchg_u8_local(ptr, old, new);
+                case 2:
+                        return __cmpxchg_u16_local(ptr, old, new);
+                case 4:
+                        return __cmpxchg_u32_local(ptr, old, new);
+                case 8:
+                        return __cmpxchg_u64_local(ptr, old, new);
+        }
+        __cmpxchg_called_with_bad_pointer();
+        return old;
+}
+
+#define cmpxchg_local(ptr,o,n)                                           \
+  ({                                                                     \
+     __typeof__(*(ptr)) _o_ = (o);                                       \
+     __typeof__(*(ptr)) _n_ = (n);                                       \
+     (__typeof__(*(ptr))) __cmpxchg_local((ptr), (unsigned long)_o_,     \
+                                    (unsigned long)_n_, sizeof(*(ptr))); \
+  })
+
 #endif /* __ASSEMBLY__ */
 
 #define arch_align_stack(x) (x)