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-rw-r--r--arch/x86/include/asm/atomic64_32.h160
1 files changed, 160 insertions, 0 deletions
diff --git a/arch/x86/include/asm/atomic64_32.h b/arch/x86/include/asm/atomic64_32.h
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+++ b/arch/x86/include/asm/atomic64_32.h
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+#ifndef _ASM_X86_ATOMIC64_32_H
+#define _ASM_X86_ATOMIC64_32_H
+
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include <asm/processor.h>
+//#include <asm/cmpxchg.h>
+
+/* An 64bit atomic type */
+
+typedef struct {
+ u64 __aligned(8) counter;
+} atomic64_t;
+
+#define ATOMIC64_INIT(val) { (val) }
+
+extern u64 atomic64_cmpxchg(atomic64_t *ptr, u64 old_val, u64 new_val);
+
+/**
+ * atomic64_xchg - xchg atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ * @new_val: value to assign
+ *
+ * Atomically xchgs the value of @ptr to @new_val and returns
+ * the old value.
+ */
+extern u64 atomic64_xchg(atomic64_t *ptr, u64 new_val);
+
+/**
+ * atomic64_set - set atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ * @new_val: value to assign
+ *
+ * Atomically sets the value of @ptr to @new_val.
+ */
+extern void atomic64_set(atomic64_t *ptr, u64 new_val);
+
+/**
+ * atomic64_read - read atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically reads the value of @ptr and returns it.
+ */
+static inline u64 atomic64_read(atomic64_t *ptr)
+{
+ u64 res;
+
+ /*
+ * Note, we inline this atomic64_t primitive because
+ * it only clobbers EAX/EDX and leaves the others
+ * untouched. We also (somewhat subtly) rely on the
+ * fact that cmpxchg8b returns the current 64-bit value
+ * of the memory location we are touching:
+ */
+ asm volatile(
+ "mov %%ebx, %%eax\n\t"
+ "mov %%ecx, %%edx\n\t"
+ LOCK_PREFIX "cmpxchg8b %1\n"
+ : "=&A" (res)
+ : "m" (*ptr)
+ );
+
+ return res;
+}
+
+extern u64 atomic64_read(atomic64_t *ptr);
+
+/**
+ * atomic64_add_return - add and return
+ * @delta: integer value to add
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically adds @delta to @ptr and returns @delta + *@ptr
+ */
+extern u64 atomic64_add_return(u64 delta, atomic64_t *ptr);
+
+/*
+ * Other variants with different arithmetic operators:
+ */
+extern u64 atomic64_sub_return(u64 delta, atomic64_t *ptr);
+extern u64 atomic64_inc_return(atomic64_t *ptr);
+extern u64 atomic64_dec_return(atomic64_t *ptr);
+
+/**
+ * atomic64_add - add integer to atomic64 variable
+ * @delta: integer value to add
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically adds @delta to @ptr.
+ */
+extern void atomic64_add(u64 delta, atomic64_t *ptr);
+
+/**
+ * atomic64_sub - subtract the atomic64 variable
+ * @delta: integer value to subtract
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically subtracts @delta from @ptr.
+ */
+extern void atomic64_sub(u64 delta, atomic64_t *ptr);
+
+/**
+ * atomic64_sub_and_test - subtract value from variable and test result
+ * @delta: integer value to subtract
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically subtracts @delta from @ptr and returns
+ * true if the result is zero, or false for all
+ * other cases.
+ */
+extern int atomic64_sub_and_test(u64 delta, atomic64_t *ptr);
+
+/**
+ * atomic64_inc - increment atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically increments @ptr by 1.
+ */
+extern void atomic64_inc(atomic64_t *ptr);
+
+/**
+ * atomic64_dec - decrement atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically decrements @ptr by 1.
+ */
+extern void atomic64_dec(atomic64_t *ptr);
+
+/**
+ * atomic64_dec_and_test - decrement and test
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically decrements @ptr by 1 and
+ * returns true if the result is 0, or false for all other
+ * cases.
+ */
+extern int atomic64_dec_and_test(atomic64_t *ptr);
+
+/**
+ * atomic64_inc_and_test - increment and test
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically increments @ptr by 1
+ * and returns true if the result is zero, or false for all
+ * other cases.
+ */
+extern int atomic64_inc_and_test(atomic64_t *ptr);
+
+/**
+ * atomic64_add_negative - add and test if negative
+ * @delta: integer value to add
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically adds @delta to @ptr and returns true
+ * if the result is negative, or false when
+ * result is greater than or equal to zero.
+ */
+extern int atomic64_add_negative(u64 delta, atomic64_t *ptr);
+
+#endif /* _ASM_X86_ATOMIC64_32_H */