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-rw-r--r--arch/powerpc/include/asm/local.h159
1 files changed, 159 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/local.h b/arch/powerpc/include/asm/local.h
new file mode 100644
index 000000000..45492fb5b
--- /dev/null
+++ b/arch/powerpc/include/asm/local.h
@@ -0,0 +1,159 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ARCH_POWERPC_LOCAL_H
+#define _ARCH_POWERPC_LOCAL_H
+
+#ifdef CONFIG_PPC_BOOK3S_64
+
+#include <linux/percpu.h>
+#include <linux/atomic.h>
+#include <linux/irqflags.h>
+
+#include <asm/hw_irq.h>
+
+typedef struct
+{
+ long v;
+} local_t;
+
+#define LOCAL_INIT(i) { (i) }
+
+static __inline__ long local_read(const local_t *l)
+{
+ return READ_ONCE(l->v);
+}
+
+static __inline__ void local_set(local_t *l, long i)
+{
+ WRITE_ONCE(l->v, i);
+}
+
+#define LOCAL_OP(op, c_op) \
+static __inline__ void local_##op(long i, local_t *l) \
+{ \
+ unsigned long flags; \
+ \
+ powerpc_local_irq_pmu_save(flags); \
+ l->v c_op i; \
+ powerpc_local_irq_pmu_restore(flags); \
+}
+
+#define LOCAL_OP_RETURN(op, c_op) \
+static __inline__ long local_##op##_return(long a, local_t *l) \
+{ \
+ long t; \
+ unsigned long flags; \
+ \
+ powerpc_local_irq_pmu_save(flags); \
+ t = (l->v c_op a); \
+ powerpc_local_irq_pmu_restore(flags); \
+ \
+ return t; \
+}
+
+#define LOCAL_OPS(op, c_op) \
+ LOCAL_OP(op, c_op) \
+ LOCAL_OP_RETURN(op, c_op)
+
+LOCAL_OPS(add, +=)
+LOCAL_OPS(sub, -=)
+
+#define local_add_negative(a, l) (local_add_return((a), (l)) < 0)
+#define local_inc_return(l) local_add_return(1LL, l)
+#define local_inc(l) local_inc_return(l)
+
+/*
+ * local_inc_and_test - increment and test
+ * @l: pointer of type local_t
+ *
+ * Atomically increments @l by 1
+ * and returns true if the result is zero, or false for all
+ * other cases.
+ */
+#define local_inc_and_test(l) (local_inc_return(l) == 0)
+
+#define local_dec_return(l) local_sub_return(1LL, l)
+#define local_dec(l) local_dec_return(l)
+#define local_sub_and_test(a, l) (local_sub_return((a), (l)) == 0)
+#define local_dec_and_test(l) (local_dec_return((l)) == 0)
+
+static __inline__ long local_cmpxchg(local_t *l, long o, long n)
+{
+ long t;
+ unsigned long flags;
+
+ powerpc_local_irq_pmu_save(flags);
+ t = l->v;
+ if (t == o)
+ l->v = n;
+ powerpc_local_irq_pmu_restore(flags);
+
+ return t;
+}
+
+static __inline__ bool local_try_cmpxchg(local_t *l, long *po, long n)
+{
+ long o = *po, r;
+
+ r = local_cmpxchg(l, o, n);
+ if (unlikely(r != o))
+ *po = r;
+
+ return likely(r == o);
+}
+
+static __inline__ long local_xchg(local_t *l, long n)
+{
+ long t;
+ unsigned long flags;
+
+ powerpc_local_irq_pmu_save(flags);
+ t = l->v;
+ l->v = n;
+ powerpc_local_irq_pmu_restore(flags);
+
+ return t;
+}
+
+/**
+ * local_add_unless - add unless the number is a given value
+ * @l: pointer of type local_t
+ * @a: the amount to add to v...
+ * @u: ...unless v 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.
+ */
+static __inline__ int local_add_unless(local_t *l, long a, long u)
+{
+ unsigned long flags;
+ int ret = 0;
+
+ powerpc_local_irq_pmu_save(flags);
+ if (l->v != u) {
+ l->v += a;
+ ret = 1;
+ }
+ powerpc_local_irq_pmu_restore(flags);
+
+ return ret;
+}
+
+#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
+
+/* 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 __local_inc(l) ((l)->v++)
+#define __local_dec(l) ((l)->v++)
+#define __local_add(i,l) ((l)->v+=(i))
+#define __local_sub(i,l) ((l)->v-=(i))
+
+#else /* CONFIG_PPC64 */
+
+#include <asm-generic/local.h>
+
+#endif /* CONFIG_PPC64 */
+
+#endif /* _ARCH_POWERPC_LOCAL_H */