atomic.h: atomic_add_unless as inline. Remove system.h atomic.h circular dependency

atomic_add_unless as inline. Remove system.h atomic.h circular dependency.
I agree (with Andi Kleen) this typeof is not needed and more error
prone. All the original atomic.h code that uses cmpxchg (which includes
the atomic_add_unless) uses defines instead of inline functions,
probably to circumvent a circular dependency between system.h and
atomic.h on powerpc (which my patch addresses). Therefore, it makes
sense to use inline functions that will provide type checking.

atomic_add_unless as inline. Remove system.h atomic.h circular dependency.
Digging into the FRV architecture shows me that it is also affected by
such a circular dependency. Here is the diff applying this against the
rest of my atomic.h patches.

It applies over the atomic.h standardization patches.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 84 insertions, 77 deletions

diff --git a/include/asm-frv/atomic.h b/include/asm-frv/atomic.h
index 066386ac238..d425d8d0ad7 100644
--- a/include/asm-frv/atomic.h
+++ b/include/asm-frv/atomic.h
@@ -16,6 +16,7 @@
 
 #include <linux/types.h>
 #include <asm/spr-regs.h>
+#include <asm/system.h>
 
 #ifdef CONFIG_SMP
 #error not SMP safe
@@ -258,85 +259,23 @@ extern uint32_t __xchg_32(uint32_t i, volatile void *v);
 
 #define tas(ptr) (xchg((ptr), 1))
 
-/*****************************************************************************/
-/*
- * compare and conditionally exchange value with memory
- * - if (*ptr == test) then orig = *ptr; *ptr = test;
- * - if (*ptr != test) then orig = *ptr;
- */
-#ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS
-
-#define cmpxchg(ptr, test, new)                                                 \
-({                                                                              \
-        __typeof__(ptr) __xg_ptr = (ptr);                                       \
-        __typeof__(*(ptr)) __xg_orig, __xg_tmp;                                 \
-        __typeof__(*(ptr)) __xg_test = (test);                                  \
-        __typeof__(*(ptr)) __xg_new = (new);                                    \
-                                                                                \
-        switch (sizeof(__xg_orig)) {                                            \
-        case 4:                                                                 \
-                asm volatile(                                                   \
-                        "0:                                             \n"     \
-                        "       orcc            gr0,gr0,gr0,icc3        \n"     \
-                        "       ckeq            icc3,cc7                \n"     \
-                        "       ld.p            %M0,%1                  \n"     \
-                        "       orcr            cc7,cc7,cc3             \n"     \
-                        "       sub%I4cc        %1,%4,%2,icc0           \n"     \
-                        "       bne             icc0,#0,1f              \n"     \
-                        "       cst.p           %3,%M0          ,cc3,#1 \n"     \
-                        "       corcc           gr29,gr29,gr0   ,cc3,#1 \n"     \
-                        "       beq             icc3,#0,0b              \n"     \
-                        "1:                                             \n"     \
-                        : "+U"(*__xg_ptr), "=&r"(__xg_orig), "=&r"(__xg_tmp)    \
-                        : "r"(__xg_new), "NPr"(__xg_test)                       \
-                        : "memory", "cc7", "cc3", "icc3", "icc0"                \
-                        );                                                      \
-                break;                                                          \
-                                                                                \
-        default:                                                                \
-                __xg_orig = 0;                                                  \
-                asm volatile("break");                                          \
-                break;                                                          \
-        }                                                                       \
-                                                                                \
-        __xg_orig;                                                              \
-})
-
-#else
-
-extern uint32_t __cmpxchg_32(uint32_t *v, uint32_t test, uint32_t new);
-
-#define cmpxchg(ptr, test, new)                                                 \
-({                                                                              \
-        __typeof__(ptr) __xg_ptr = (ptr);                                       \
-        __typeof__(*(ptr)) __xg_orig;                                           \
-        __typeof__(*(ptr)) __xg_test = (test);                                  \
-        __typeof__(*(ptr)) __xg_new = (new);                                    \
-                                                                                \
-        switch (sizeof(__xg_orig)) {                                            \
-        case 4: __xg_orig = __cmpxchg_32(__xg_ptr, __xg_test, __xg_new); break; \
-        default:                                                                \
-                __xg_orig = 0;                                                  \
-                asm volatile("break");                                          \
-                break;                                                          \
-        }                                                                       \
-                                                                                \
-        __xg_orig;                                                              \
-})
-
-#endif
-
 #define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
 
-#define atomic_add_unless(v, a, u)                              \
-({                                                              \
-        int c, old;                                             \
-        c = atomic_read(v);                                     \
-        while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \
-                c = old;                                        \
-        c != (u);                                               \
-})
+static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+{
+        int c, old;
+        c = atomic_read(v);
+        for (;;) {
+                if (unlikely(c == (u)))
+                        break;
+                old = atomic_cmpxchg((v), c, c + (a));
+                if (likely(old == c))
+                        break;
+                c = old;
+        }
+        return c != (u);
+}
 
 #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
 
diff --git a/include/asm-frv/system.h b/include/asm-frv/system.h
index 1166899317d..be303b3eef4 100644
--- a/include/asm-frv/system.h
+++ b/include/asm-frv/system.h
@@ -13,7 +13,6 @@
 #define _ASM_SYSTEM_H
 
 #include <linux/linkage.h>
-#include <asm/atomic.h>
 
 struct thread_struct;
 
@@ -197,4 +196,73 @@ extern void free_initmem(void);
 
 #define arch_align_stack(x) (x)
 
+/*****************************************************************************/
+/*
+ * compare and conditionally exchange value with memory
+ * - if (*ptr == test) then orig = *ptr; *ptr = test;
+ * - if (*ptr != test) then orig = *ptr;
+ */
+#ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS
+
+#define cmpxchg(ptr, test, new)                                                 \
+({                                                                              \
+        __typeof__(ptr) __xg_ptr = (ptr);                                       \
+        __typeof__(*(ptr)) __xg_orig, __xg_tmp;                                 \
+        __typeof__(*(ptr)) __xg_test = (test);                                  \
+        __typeof__(*(ptr)) __xg_new = (new);                                    \
+                                                                                \
+        switch (sizeof(__xg_orig)) {                                            \
+        case 4:                                                                 \
+                asm volatile(                                                   \
+                        "0:                                             \n"     \
+                        "       orcc            gr0,gr0,gr0,icc3        \n"     \
+                        "       ckeq            icc3,cc7                \n"     \
+                        "       ld.p            %M0,%1                  \n"     \
+                        "       orcr            cc7,cc7,cc3             \n"     \
+                        "       sub%I4cc        %1,%4,%2,icc0           \n"     \
+                        "       bne             icc0,#0,1f              \n"     \
+                        "       cst.p           %3,%M0          ,cc3,#1 \n"     \
+                        "       corcc           gr29,gr29,gr0   ,cc3,#1 \n"     \
+                        "       beq             icc3,#0,0b              \n"     \
+                        "1:                                             \n"     \
+                        : "+U"(*__xg_ptr), "=&r"(__xg_orig), "=&r"(__xg_tmp)    \
+                        : "r"(__xg_new), "NPr"(__xg_test)                       \
+                        : "memory", "cc7", "cc3", "icc3", "icc0"                \
+                        );                                                      \
+                break;                                                          \
+                                                                                \
+        default:                                                                \
+                __xg_orig = 0;                                                  \
+                asm volatile("break");                                          \
+                break;                                                          \
+        }                                                                       \
+                                                                                \
+        __xg_orig;                                                              \
+})
+
+#else
+
+extern uint32_t __cmpxchg_32(uint32_t *v, uint32_t test, uint32_t new);
+
+#define cmpxchg(ptr, test, new)                                                 \
+({                                                                              \
+        __typeof__(ptr) __xg_ptr = (ptr);                                       \
+        __typeof__(*(ptr)) __xg_orig;                                           \
+        __typeof__(*(ptr)) __xg_test = (test);                                  \
+        __typeof__(*(ptr)) __xg_new = (new);                                    \
+                                                                                \
+        switch (sizeof(__xg_orig)) {                                            \
+        case 4: __xg_orig = __cmpxchg_32(__xg_ptr, __xg_test, __xg_new); break; \
+        default:                                                                \
+                __xg_orig = 0;                                                  \
+                asm volatile("break");                                          \
+                break;                                                          \
+        }                                                                       \
+                                                                                \
+        __xg_orig;                                                              \
+})
+
+#endif
+
+
 #endif /* _ASM_SYSTEM_H */