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authorDavid S. Miller <davem@davemloft.net>2009-04-13 14:41:05 -0700
committerDavid S. Miller <davem@davemloft.net>2009-04-13 14:41:05 -0700
commit83400207a07584539366f6859362db6872809a12 (patch)
treefad187f8b3bebf1b387ec42ef8143e6f4e49a256 /arch/microblaze/include/asm/atomic.h
parent0d489ffb76de0fe804cf06a9d4d11fa7342d74b9 (diff)
parent80a04d3f2f94fb68b5df05e3ac6697130bc3467a (diff)
Merge branch 'master' of /home/davem/src/GIT/linux-2.6/
Conflicts: MAINTAINERS
Diffstat (limited to 'arch/microblaze/include/asm/atomic.h')
-rw-r--r--arch/microblaze/include/asm/atomic.h123
1 files changed, 123 insertions, 0 deletions
diff --git a/arch/microblaze/include/asm/atomic.h b/arch/microblaze/include/asm/atomic.h
new file mode 100644
index 00000000000..a448d94ab72
--- /dev/null
+++ b/arch/microblaze/include/asm/atomic.h
@@ -0,0 +1,123 @@
+/*
+ * Copyright (C) 2006 Atmark Techno, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_MICROBLAZE_ATOMIC_H
+#define _ASM_MICROBLAZE_ATOMIC_H
+
+#include <linux/types.h>
+#include <linux/compiler.h> /* likely */
+#include <asm/system.h> /* local_irq_XXX and friends */
+
+#define ATOMIC_INIT(i) { (i) }
+#define atomic_read(v) ((v)->counter)
+#define atomic_set(v, i) (((v)->counter) = (i))
+
+#define atomic_inc(v) (atomic_add_return(1, (v)))
+#define atomic_dec(v) (atomic_sub_return(1, (v)))
+
+#define atomic_add(i, v) (atomic_add_return(i, (v)))
+#define atomic_sub(i, v) (atomic_sub_return(i, (v)))
+
+#define atomic_inc_return(v) (atomic_add_return(1, (v)))
+#define atomic_dec_return(v) (atomic_sub_return(1, (v)))
+
+#define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0)
+#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
+
+#define atomic_inc_not_zero(v) (atomic_add_unless((v), 1, 0))
+
+#define atomic_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0)
+
+static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+ int ret;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ ret = v->counter;
+ if (likely(ret == old))
+ v->counter = new;
+ local_irq_restore(flags);
+
+ return ret;
+}
+
+static inline int atomic_add_unless(atomic_t *v, int a, int u)
+{
+ int c, old;
+
+ c = atomic_read(v);
+ while (c != u && (old = atomic_cmpxchg((v), c, c + a)) != c)
+ c = old;
+ return c != u;
+}
+
+static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ *addr &= ~mask;
+ local_irq_restore(flags);
+}
+
+/**
+ * atomic_add_return - add and return
+ * @i: integer value to add
+ * @v: pointer of type atomic_t
+ *
+ * Atomically adds @i to @v and returns @i + @v
+ */
+static inline int atomic_add_return(int i, atomic_t *v)
+{
+ unsigned long flags;
+ int val;
+
+ local_irq_save(flags);
+ val = v->counter;
+ v->counter = val += i;
+ local_irq_restore(flags);
+
+ return val;
+}
+
+static inline int atomic_sub_return(int i, atomic_t *v)
+{
+ return atomic_add_return(-i, v);
+}
+
+/*
+ * Atomically test *v and decrement if it is greater than 0.
+ * The function returns the old value of *v minus 1.
+ */
+static inline int atomic_dec_if_positive(atomic_t *v)
+{
+ unsigned long flags;
+ int res;
+
+ local_irq_save(flags);
+ res = v->counter - 1;
+ if (res >= 0)
+ v->counter = res;
+ local_irq_restore(flags);
+
+ return res;
+}
+
+#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
+/* Atomic operations are already serializing */
+#define smp_mb__before_atomic_dec() barrier()
+#define smp_mb__after_atomic_dec() barrier()
+#define smp_mb__before_atomic_inc() barrier()
+#define smp_mb__after_atomic_inc() barrier()
+
+#include <asm-generic/atomic.h>
+
+#endif /* _ASM_MICROBLAZE_ATOMIC_H */