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-rw-r--r--kernel/arch/sparc/lib/atomic_64.S104
1 files changed, 104 insertions, 0 deletions
diff --git a/kernel/arch/sparc/lib/atomic_64.S b/kernel/arch/sparc/lib/atomic_64.S
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+++ b/kernel/arch/sparc/lib/atomic_64.S
@@ -0,0 +1,104 @@
+/* atomic.S: These things are too big to do inline.
+ *
+ * Copyright (C) 1999, 2007 2012 David S. Miller (davem@davemloft.net)
+ */
+
+#include <linux/linkage.h>
+#include <asm/asi.h>
+#include <asm/backoff.h>
+
+ .text
+
+ /* Two versions of the atomic routines, one that
+ * does not return a value and does not perform
+ * memory barriers, and a second which returns
+ * a value and does the barriers.
+ */
+
+#define ATOMIC_OP(op) \
+ENTRY(atomic_##op) /* %o0 = increment, %o1 = atomic_ptr */ \
+ BACKOFF_SETUP(%o2); \
+1: lduw [%o1], %g1; \
+ op %g1, %o0, %g7; \
+ cas [%o1], %g1, %g7; \
+ cmp %g1, %g7; \
+ bne,pn %icc, BACKOFF_LABEL(2f, 1b); \
+ nop; \
+ retl; \
+ nop; \
+2: BACKOFF_SPIN(%o2, %o3, 1b); \
+ENDPROC(atomic_##op); \
+
+#define ATOMIC_OP_RETURN(op) \
+ENTRY(atomic_##op##_return) /* %o0 = increment, %o1 = atomic_ptr */ \
+ BACKOFF_SETUP(%o2); \
+1: lduw [%o1], %g1; \
+ op %g1, %o0, %g7; \
+ cas [%o1], %g1, %g7; \
+ cmp %g1, %g7; \
+ bne,pn %icc, BACKOFF_LABEL(2f, 1b); \
+ op %g1, %o0, %g1; \
+ retl; \
+ sra %g1, 0, %o0; \
+2: BACKOFF_SPIN(%o2, %o3, 1b); \
+ENDPROC(atomic_##op##_return);
+
+#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
+
+ATOMIC_OPS(add)
+ATOMIC_OPS(sub)
+
+#undef ATOMIC_OPS
+#undef ATOMIC_OP_RETURN
+#undef ATOMIC_OP
+
+#define ATOMIC64_OP(op) \
+ENTRY(atomic64_##op) /* %o0 = increment, %o1 = atomic_ptr */ \
+ BACKOFF_SETUP(%o2); \
+1: ldx [%o1], %g1; \
+ op %g1, %o0, %g7; \
+ casx [%o1], %g1, %g7; \
+ cmp %g1, %g7; \
+ bne,pn %xcc, BACKOFF_LABEL(2f, 1b); \
+ nop; \
+ retl; \
+ nop; \
+2: BACKOFF_SPIN(%o2, %o3, 1b); \
+ENDPROC(atomic64_##op); \
+
+#define ATOMIC64_OP_RETURN(op) \
+ENTRY(atomic64_##op##_return) /* %o0 = increment, %o1 = atomic_ptr */ \
+ BACKOFF_SETUP(%o2); \
+1: ldx [%o1], %g1; \
+ op %g1, %o0, %g7; \
+ casx [%o1], %g1, %g7; \
+ cmp %g1, %g7; \
+ bne,pn %xcc, BACKOFF_LABEL(2f, 1b); \
+ nop; \
+ retl; \
+ op %g1, %o0, %o0; \
+2: BACKOFF_SPIN(%o2, %o3, 1b); \
+ENDPROC(atomic64_##op##_return);
+
+#define ATOMIC64_OPS(op) ATOMIC64_OP(op) ATOMIC64_OP_RETURN(op)
+
+ATOMIC64_OPS(add)
+ATOMIC64_OPS(sub)
+
+#undef ATOMIC64_OPS
+#undef ATOMIC64_OP_RETURN
+#undef ATOMIC64_OP
+
+ENTRY(atomic64_dec_if_positive) /* %o0 = atomic_ptr */
+ BACKOFF_SETUP(%o2)
+1: ldx [%o0], %g1
+ brlez,pn %g1, 3f
+ sub %g1, 1, %g7
+ casx [%o0], %g1, %g7
+ cmp %g1, %g7
+ bne,pn %xcc, BACKOFF_LABEL(2f, 1b)
+ nop
+3: retl
+ sub %g1, 1, %o0
+2: BACKOFF_SPIN(%o2, %o3, 1b)
+ENDPROC(atomic64_dec_if_positive)