#ifndef _ASM_GENERIC_PERCPU_H_
#define _ASM_GENERIC_PERCPU_H_
+
#include <linux/compiler.h>
#include <linux/threads.h>
+#include <linux/percpu-defs.h>
-#define __GENERIC_PER_CPU
#ifdef CONFIG_SMP
+/*
+ * per_cpu_offset() is the offset that has to be added to a
+ * percpu variable to get to the instance for a certain processor.
+ *
+ * Most arches use the __per_cpu_offset array for those offsets but
+ * some arches have their own ways of determining the offset (x86_64, s390).
+ */
+#ifndef __per_cpu_offset
extern unsigned long __per_cpu_offset[NR_CPUS];
#define per_cpu_offset(x) (__per_cpu_offset[x])
+#endif
-/* Separate out the type, so (int[3], foo) works. */
-#define DEFINE_PER_CPU(type, name) \
- __attribute__((__section__(".data.percpu"))) __typeof__(type) per_cpu__##name
-
-#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \
- __attribute__((__section__(".data.percpu.shared_aligned"))) \
- __typeof__(type) per_cpu__##name \
- ____cacheline_aligned_in_smp
-
-/* var is in discarded region: offset to particular copy we want */
-#define per_cpu(var, cpu) (*({ \
- extern int simple_identifier_##var(void); \
- RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu]); }))
-#define __get_cpu_var(var) per_cpu(var, smp_processor_id())
-#define __raw_get_cpu_var(var) per_cpu(var, raw_smp_processor_id())
-
-/* A macro to avoid #include hell... */
-#define percpu_modcopy(pcpudst, src, size) \
-do { \
- unsigned int __i; \
- for_each_possible_cpu(__i) \
- memcpy((pcpudst)+__per_cpu_offset[__i], \
- (src), (size)); \
-} while (0)
-#else /* ! SMP */
+/*
+ * Determine the offset for the currently active processor.
+ * An arch may define __my_cpu_offset to provide a more effective
+ * means of obtaining the offset to the per cpu variables of the
+ * current processor.
+ */
+#ifndef __my_cpu_offset
+#define __my_cpu_offset per_cpu_offset(raw_smp_processor_id())
+#endif
+#ifdef CONFIG_DEBUG_PREEMPT
+#define my_cpu_offset per_cpu_offset(smp_processor_id())
+#else
+#define my_cpu_offset __my_cpu_offset
+#endif
+
+/*
+ * Add a offset to a pointer but keep the pointer as is.
+ *
+ * Only S390 provides its own means of moving the pointer.
+ */
+#ifndef SHIFT_PERCPU_PTR
+/* Weird cast keeps both GCC and sparse happy. */
+#define SHIFT_PERCPU_PTR(__p, __offset) ({ \
+ __verify_pcpu_ptr((__p)); \
+ RELOC_HIDE((typeof(*(__p)) __kernel __force *)(__p), (__offset)); \
+})
+#endif
+
+/*
+ * A percpu variable may point to a discarded regions. The following are
+ * established ways to produce a usable pointer from the percpu variable
+ * offset.
+ */
+#define per_cpu(var, cpu) \
+ (*SHIFT_PERCPU_PTR(&(var), per_cpu_offset(cpu)))
+#define __get_cpu_var(var) \
+ (*SHIFT_PERCPU_PTR(&(var), my_cpu_offset))
+#define __raw_get_cpu_var(var) \
+ (*SHIFT_PERCPU_PTR(&(var), __my_cpu_offset))
-#define DEFINE_PER_CPU(type, name) \
- __typeof__(type) per_cpu__##name
+#define this_cpu_ptr(ptr) SHIFT_PERCPU_PTR(ptr, my_cpu_offset)
+#define __this_cpu_ptr(ptr) SHIFT_PERCPU_PTR(ptr, __my_cpu_offset)
-#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \
- DEFINE_PER_CPU(type, name)
-#define per_cpu(var, cpu) (*((void)(cpu), &per_cpu__##var))
-#define __get_cpu_var(var) per_cpu__##var
-#define __raw_get_cpu_var(var) per_cpu__##var
+#ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
+extern void setup_per_cpu_areas(void);
+#endif
+
+#else /* ! SMP */
+
+#define per_cpu(var, cpu) (*((void)(cpu), &(var)))
+#define __get_cpu_var(var) (var)
+#define __raw_get_cpu_var(var) (var)
+#define this_cpu_ptr(ptr) per_cpu_ptr(ptr, 0)
+#define __this_cpu_ptr(ptr) this_cpu_ptr(ptr)
#endif /* SMP */
-#define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu__##name
+#ifndef PER_CPU_BASE_SECTION
+#ifdef CONFIG_SMP
+#define PER_CPU_BASE_SECTION ".data..percpu"
+#else
+#define PER_CPU_BASE_SECTION ".data"
+#endif
+#endif
+
+#ifdef CONFIG_SMP
+
+#ifdef MODULE
+#define PER_CPU_SHARED_ALIGNED_SECTION ""
+#define PER_CPU_ALIGNED_SECTION ""
+#else
+#define PER_CPU_SHARED_ALIGNED_SECTION "..shared_aligned"
+#define PER_CPU_ALIGNED_SECTION "..shared_aligned"
+#endif
+#define PER_CPU_FIRST_SECTION "..first"
+
+#else
+
+#define PER_CPU_SHARED_ALIGNED_SECTION ""
+#define PER_CPU_ALIGNED_SECTION "..shared_aligned"
+#define PER_CPU_FIRST_SECTION ""
+
+#endif
+
+#ifndef PER_CPU_ATTRIBUTES
+#define PER_CPU_ATTRIBUTES
+#endif
-#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
-#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)
+#ifndef PER_CPU_DEF_ATTRIBUTES
+#define PER_CPU_DEF_ATTRIBUTES
+#endif
#endif /* _ASM_GENERIC_PERCPU_H_ */
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