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-rw-r--r--arch/x86/include/asm/percpu.h589
1 files changed, 589 insertions, 0 deletions
diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h
new file mode 100644
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+++ b/arch/x86/include/asm/percpu.h
@@ -0,0 +1,589 @@
+#ifndef _ASM_X86_PERCPU_H
+#define _ASM_X86_PERCPU_H
+
+#ifdef CONFIG_X86_64
+#define __percpu_seg gs
+#define __percpu_mov_op movq
+#else
+#define __percpu_seg fs
+#define __percpu_mov_op movl
+#endif
+
+#ifdef __ASSEMBLY__
+
+/*
+ * PER_CPU finds an address of a per-cpu variable.
+ *
+ * Args:
+ * var - variable name
+ * reg - 32bit register
+ *
+ * The resulting address is stored in the "reg" argument.
+ *
+ * Example:
+ * PER_CPU(cpu_gdt_descr, %ebx)
+ */
+#ifdef CONFIG_SMP
+#define PER_CPU(var, reg) \
+ __percpu_mov_op %__percpu_seg:this_cpu_off, reg; \
+ lea var(reg), reg
+#define PER_CPU_VAR(var) %__percpu_seg:var
+#else /* ! SMP */
+#define PER_CPU(var, reg) __percpu_mov_op $var, reg
+#define PER_CPU_VAR(var) var
+#endif /* SMP */
+
+#ifdef CONFIG_X86_64_SMP
+#define INIT_PER_CPU_VAR(var) init_per_cpu__##var
+#else
+#define INIT_PER_CPU_VAR(var) var
+#endif
+
+#else /* ...!ASSEMBLY */
+
+#include <linux/kernel.h>
+#include <linux/stringify.h>
+
+#ifdef CONFIG_SMP
+#define __percpu_prefix "%%"__stringify(__percpu_seg)":"
+#define __my_cpu_offset percpu_read(this_cpu_off)
+
+/*
+ * Compared to the generic __my_cpu_offset version, the following
+ * saves one instruction and avoids clobbering a temp register.
+ */
+#define __this_cpu_ptr(ptr) \
+({ \
+ unsigned long tcp_ptr__; \
+ __verify_pcpu_ptr(ptr); \
+ asm volatile("add " __percpu_arg(1) ", %0" \
+ : "=r" (tcp_ptr__) \
+ : "m" (this_cpu_off), "0" (ptr)); \
+ (typeof(*(ptr)) __kernel __force *)tcp_ptr__; \
+})
+#else
+#define __percpu_prefix ""
+#endif
+
+#define __percpu_arg(x) __percpu_prefix "%P" #x
+
+/*
+ * Initialized pointers to per-cpu variables needed for the boot
+ * processor need to use these macros to get the proper address
+ * offset from __per_cpu_load on SMP.
+ *
+ * There also must be an entry in vmlinux_64.lds.S
+ */
+#define DECLARE_INIT_PER_CPU(var) \
+ extern typeof(var) init_per_cpu_var(var)
+
+#ifdef CONFIG_X86_64_SMP
+#define init_per_cpu_var(var) init_per_cpu__##var
+#else
+#define init_per_cpu_var(var) var
+#endif
+
+/* For arch-specific code, we can use direct single-insn ops (they
+ * don't give an lvalue though). */
+extern void __bad_percpu_size(void);
+
+#define percpu_to_op(op, var, val) \
+do { \
+ typedef typeof(var) pto_T__; \
+ if (0) { \
+ pto_T__ pto_tmp__; \
+ pto_tmp__ = (val); \
+ (void)pto_tmp__; \
+ } \
+ switch (sizeof(var)) { \
+ case 1: \
+ asm(op "b %1,"__percpu_arg(0) \
+ : "+m" (var) \
+ : "qi" ((pto_T__)(val))); \
+ break; \
+ case 2: \
+ asm(op "w %1,"__percpu_arg(0) \
+ : "+m" (var) \
+ : "ri" ((pto_T__)(val))); \
+ break; \
+ case 4: \
+ asm(op "l %1,"__percpu_arg(0) \
+ : "+m" (var) \
+ : "ri" ((pto_T__)(val))); \
+ break; \
+ case 8: \
+ asm(op "q %1,"__percpu_arg(0) \
+ : "+m" (var) \
+ : "re" ((pto_T__)(val))); \
+ break; \
+ default: __bad_percpu_size(); \
+ } \
+} while (0)
+
+/*
+ * Generate a percpu add to memory instruction and optimize code
+ * if one is added or subtracted.
+ */
+#define percpu_add_op(var, val) \
+do { \
+ typedef typeof(var) pao_T__; \
+ const int pao_ID__ = (__builtin_constant_p(val) && \
+ ((val) == 1 || (val) == -1)) ? (val) : 0; \
+ if (0) { \
+ pao_T__ pao_tmp__; \
+ pao_tmp__ = (val); \
+ (void)pao_tmp__; \
+ } \
+ switch (sizeof(var)) { \
+ case 1: \
+ if (pao_ID__ == 1) \
+ asm("incb "__percpu_arg(0) : "+m" (var)); \
+ else if (pao_ID__ == -1) \
+ asm("decb "__percpu_arg(0) : "+m" (var)); \
+ else \
+ asm("addb %1, "__percpu_arg(0) \
+ : "+m" (var) \
+ : "qi" ((pao_T__)(val))); \
+ break; \
+ case 2: \
+ if (pao_ID__ == 1) \
+ asm("incw "__percpu_arg(0) : "+m" (var)); \
+ else if (pao_ID__ == -1) \
+ asm("decw "__percpu_arg(0) : "+m" (var)); \
+ else \
+ asm("addw %1, "__percpu_arg(0) \
+ : "+m" (var) \
+ : "ri" ((pao_T__)(val))); \
+ break; \
+ case 4: \
+ if (pao_ID__ == 1) \
+ asm("incl "__percpu_arg(0) : "+m" (var)); \
+ else if (pao_ID__ == -1) \
+ asm("decl "__percpu_arg(0) : "+m" (var)); \
+ else \
+ asm("addl %1, "__percpu_arg(0) \
+ : "+m" (var) \
+ : "ri" ((pao_T__)(val))); \
+ break; \
+ case 8: \
+ if (pao_ID__ == 1) \
+ asm("incq "__percpu_arg(0) : "+m" (var)); \
+ else if (pao_ID__ == -1) \
+ asm("decq "__percpu_arg(0) : "+m" (var)); \
+ else \
+ asm("addq %1, "__percpu_arg(0) \
+ : "+m" (var) \
+ : "re" ((pao_T__)(val))); \
+ break; \
+ default: __bad_percpu_size(); \
+ } \
+} while (0)
+
+#define percpu_from_op(op, var, constraint) \
+({ \
+ typeof(var) pfo_ret__; \
+ switch (sizeof(var)) { \
+ case 1: \
+ asm(op "b "__percpu_arg(1)",%0" \
+ : "=q" (pfo_ret__) \
+ : constraint); \
+ break; \
+ case 2: \
+ asm(op "w "__percpu_arg(1)",%0" \
+ : "=r" (pfo_ret__) \
+ : constraint); \
+ break; \
+ case 4: \
+ asm(op "l "__percpu_arg(1)",%0" \
+ : "=r" (pfo_ret__) \
+ : constraint); \
+ break; \
+ case 8: \
+ asm(op "q "__percpu_arg(1)",%0" \
+ : "=r" (pfo_ret__) \
+ : constraint); \
+ break; \
+ default: __bad_percpu_size(); \
+ } \
+ pfo_ret__; \
+})
+
+#define percpu_unary_op(op, var) \
+({ \
+ switch (sizeof(var)) { \
+ case 1: \
+ asm(op "b "__percpu_arg(0) \
+ : "+m" (var)); \
+ break; \
+ case 2: \
+ asm(op "w "__percpu_arg(0) \
+ : "+m" (var)); \
+ break; \
+ case 4: \
+ asm(op "l "__percpu_arg(0) \
+ : "+m" (var)); \
+ break; \
+ case 8: \
+ asm(op "q "__percpu_arg(0) \
+ : "+m" (var)); \
+ break; \
+ default: __bad_percpu_size(); \
+ } \
+})
+
+/*
+ * Add return operation
+ */
+#define percpu_add_return_op(var, val) \
+({ \
+ typeof(var) paro_ret__ = val; \
+ switch (sizeof(var)) { \
+ case 1: \
+ asm("xaddb %0, "__percpu_arg(1) \
+ : "+q" (paro_ret__), "+m" (var) \
+ : : "memory"); \
+ break; \
+ case 2: \
+ asm("xaddw %0, "__percpu_arg(1) \
+ : "+r" (paro_ret__), "+m" (var) \
+ : : "memory"); \
+ break; \
+ case 4: \
+ asm("xaddl %0, "__percpu_arg(1) \
+ : "+r" (paro_ret__), "+m" (var) \
+ : : "memory"); \
+ break; \
+ case 8: \
+ asm("xaddq %0, "__percpu_arg(1) \
+ : "+re" (paro_ret__), "+m" (var) \
+ : : "memory"); \
+ break; \
+ default: __bad_percpu_size(); \
+ } \
+ paro_ret__ += val; \
+ paro_ret__; \
+})
+
+/*
+ * xchg is implemented using cmpxchg without a lock prefix. xchg is
+ * expensive due to the implied lock prefix. The processor cannot prefetch
+ * cachelines if xchg is used.
+ */
+#define percpu_xchg_op(var, nval) \
+({ \
+ typeof(var) pxo_ret__; \
+ typeof(var) pxo_new__ = (nval); \
+ switch (sizeof(var)) { \
+ case 1: \
+ asm("\n\tmov "__percpu_arg(1)",%%al" \
+ "\n1:\tcmpxchgb %2, "__percpu_arg(1) \
+ "\n\tjnz 1b" \
+ : "=&a" (pxo_ret__), "+m" (var) \
+ : "q" (pxo_new__) \
+ : "memory"); \
+ break; \
+ case 2: \
+ asm("\n\tmov "__percpu_arg(1)",%%ax" \
+ "\n1:\tcmpxchgw %2, "__percpu_arg(1) \
+ "\n\tjnz 1b" \
+ : "=&a" (pxo_ret__), "+m" (var) \
+ : "r" (pxo_new__) \
+ : "memory"); \
+ break; \
+ case 4: \
+ asm("\n\tmov "__percpu_arg(1)",%%eax" \
+ "\n1:\tcmpxchgl %2, "__percpu_arg(1) \
+ "\n\tjnz 1b" \
+ : "=&a" (pxo_ret__), "+m" (var) \
+ : "r" (pxo_new__) \
+ : "memory"); \
+ break; \
+ case 8: \
+ asm("\n\tmov "__percpu_arg(1)",%%rax" \
+ "\n1:\tcmpxchgq %2, "__percpu_arg(1) \
+ "\n\tjnz 1b" \
+ : "=&a" (pxo_ret__), "+m" (var) \
+ : "r" (pxo_new__) \
+ : "memory"); \
+ break; \
+ default: __bad_percpu_size(); \
+ } \
+ pxo_ret__; \
+})
+
+/*
+ * cmpxchg has no such implied lock semantics as a result it is much
+ * more efficient for cpu local operations.
+ */
+#define percpu_cmpxchg_op(var, oval, nval) \
+({ \
+ typeof(var) pco_ret__; \
+ typeof(var) pco_old__ = (oval); \
+ typeof(var) pco_new__ = (nval); \
+ switch (sizeof(var)) { \
+ case 1: \
+ asm("cmpxchgb %2, "__percpu_arg(1) \
+ : "=a" (pco_ret__), "+m" (var) \
+ : "q" (pco_new__), "0" (pco_old__) \
+ : "memory"); \
+ break; \
+ case 2: \
+ asm("cmpxchgw %2, "__percpu_arg(1) \
+ : "=a" (pco_ret__), "+m" (var) \
+ : "r" (pco_new__), "0" (pco_old__) \
+ : "memory"); \
+ break; \
+ case 4: \
+ asm("cmpxchgl %2, "__percpu_arg(1) \
+ : "=a" (pco_ret__), "+m" (var) \
+ : "r" (pco_new__), "0" (pco_old__) \
+ : "memory"); \
+ break; \
+ case 8: \
+ asm("cmpxchgq %2, "__percpu_arg(1) \
+ : "=a" (pco_ret__), "+m" (var) \
+ : "r" (pco_new__), "0" (pco_old__) \
+ : "memory"); \
+ break; \
+ default: __bad_percpu_size(); \
+ } \
+ pco_ret__; \
+})
+
+/*
+ * percpu_read() makes gcc load the percpu variable every time it is
+ * accessed while percpu_read_stable() allows the value to be cached.
+ * percpu_read_stable() is more efficient and can be used if its value
+ * is guaranteed to be valid across cpus. The current users include
+ * get_current() and get_thread_info() both of which are actually
+ * per-thread variables implemented as per-cpu variables and thus
+ * stable for the duration of the respective task.
+ */
+#define percpu_read(var) percpu_from_op("mov", var, "m" (var))
+#define percpu_read_stable(var) percpu_from_op("mov", var, "p" (&(var)))
+#define percpu_write(var, val) percpu_to_op("mov", var, val)
+#define percpu_add(var, val) percpu_add_op(var, val)
+#define percpu_sub(var, val) percpu_add_op(var, -(val))
+#define percpu_and(var, val) percpu_to_op("and", var, val)
+#define percpu_or(var, val) percpu_to_op("or", var, val)
+#define percpu_xor(var, val) percpu_to_op("xor", var, val)
+#define percpu_inc(var) percpu_unary_op("inc", var)
+
+#define __this_cpu_read_1(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
+#define __this_cpu_read_2(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
+#define __this_cpu_read_4(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
+
+#define __this_cpu_write_1(pcp, val) percpu_to_op("mov", (pcp), val)
+#define __this_cpu_write_2(pcp, val) percpu_to_op("mov", (pcp), val)
+#define __this_cpu_write_4(pcp, val) percpu_to_op("mov", (pcp), val)
+#define __this_cpu_add_1(pcp, val) percpu_add_op((pcp), val)
+#define __this_cpu_add_2(pcp, val) percpu_add_op((pcp), val)
+#define __this_cpu_add_4(pcp, val) percpu_add_op((pcp), val)
+#define __this_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val)
+#define __this_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val)
+#define __this_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val)
+#define __this_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val)
+#define __this_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val)
+#define __this_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val)
+#define __this_cpu_xor_1(pcp, val) percpu_to_op("xor", (pcp), val)
+#define __this_cpu_xor_2(pcp, val) percpu_to_op("xor", (pcp), val)
+#define __this_cpu_xor_4(pcp, val) percpu_to_op("xor", (pcp), val)
+#define __this_cpu_xchg_1(pcp, val) percpu_xchg_op(pcp, val)
+#define __this_cpu_xchg_2(pcp, val) percpu_xchg_op(pcp, val)
+#define __this_cpu_xchg_4(pcp, val) percpu_xchg_op(pcp, val)
+
+#define this_cpu_read_1(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
+#define this_cpu_read_2(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
+#define this_cpu_read_4(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
+#define this_cpu_write_1(pcp, val) percpu_to_op("mov", (pcp), val)
+#define this_cpu_write_2(pcp, val) percpu_to_op("mov", (pcp), val)
+#define this_cpu_write_4(pcp, val) percpu_to_op("mov", (pcp), val)
+#define this_cpu_add_1(pcp, val) percpu_add_op((pcp), val)
+#define this_cpu_add_2(pcp, val) percpu_add_op((pcp), val)
+#define this_cpu_add_4(pcp, val) percpu_add_op((pcp), val)
+#define this_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val)
+#define this_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val)
+#define this_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val)
+#define this_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val)
+#define this_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val)
+#define this_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val)
+#define this_cpu_xor_1(pcp, val) percpu_to_op("xor", (pcp), val)
+#define this_cpu_xor_2(pcp, val) percpu_to_op("xor", (pcp), val)
+#define this_cpu_xor_4(pcp, val) percpu_to_op("xor", (pcp), val)
+#define this_cpu_xchg_1(pcp, nval) percpu_xchg_op(pcp, nval)
+#define this_cpu_xchg_2(pcp, nval) percpu_xchg_op(pcp, nval)
+#define this_cpu_xchg_4(pcp, nval) percpu_xchg_op(pcp, nval)
+
+#ifndef CONFIG_M386
+#define __this_cpu_add_return_1(pcp, val) percpu_add_return_op(pcp, val)
+#define __this_cpu_add_return_2(pcp, val) percpu_add_return_op(pcp, val)
+#define __this_cpu_add_return_4(pcp, val) percpu_add_return_op(pcp, val)
+#define __this_cpu_cmpxchg_1(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
+#define __this_cpu_cmpxchg_2(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
+#define __this_cpu_cmpxchg_4(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
+
+#define this_cpu_add_return_1(pcp, val) percpu_add_return_op(pcp, val)
+#define this_cpu_add_return_2(pcp, val) percpu_add_return_op(pcp, val)
+#define this_cpu_add_return_4(pcp, val) percpu_add_return_op(pcp, val)
+#define this_cpu_cmpxchg_1(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
+#define this_cpu_cmpxchg_2(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
+#define this_cpu_cmpxchg_4(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
+
+#endif /* !CONFIG_M386 */
+
+#ifdef CONFIG_X86_CMPXCHG64
+#define percpu_cmpxchg8b_double(pcp1, pcp2, o1, o2, n1, n2) \
+({ \
+ bool __ret; \
+ typeof(pcp1) __o1 = (o1), __n1 = (n1); \
+ typeof(pcp2) __o2 = (o2), __n2 = (n2); \
+ asm volatile("cmpxchg8b "__percpu_arg(1)"\n\tsetz %0\n\t" \
+ : "=a" (__ret), "+m" (pcp1), "+m" (pcp2), "+d" (__o2) \
+ : "b" (__n1), "c" (__n2), "a" (__o1)); \
+ __ret; \
+})
+
+#define __this_cpu_cmpxchg_double_4 percpu_cmpxchg8b_double
+#define this_cpu_cmpxchg_double_4 percpu_cmpxchg8b_double
+#endif /* CONFIG_X86_CMPXCHG64 */
+
+/*
+ * Per cpu atomic 64 bit operations are only available under 64 bit.
+ * 32 bit must fall back to generic operations.
+ */
+#ifdef CONFIG_X86_64
+#define __this_cpu_read_8(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
+#define __this_cpu_write_8(pcp, val) percpu_to_op("mov", (pcp), val)
+#define __this_cpu_add_8(pcp, val) percpu_add_op((pcp), val)
+#define __this_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val)
+#define __this_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val)
+#define __this_cpu_xor_8(pcp, val) percpu_to_op("xor", (pcp), val)
+#define __this_cpu_add_return_8(pcp, val) percpu_add_return_op(pcp, val)
+#define __this_cpu_xchg_8(pcp, nval) percpu_xchg_op(pcp, nval)
+#define __this_cpu_cmpxchg_8(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
+
+#define this_cpu_read_8(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
+#define this_cpu_write_8(pcp, val) percpu_to_op("mov", (pcp), val)
+#define this_cpu_add_8(pcp, val) percpu_add_op((pcp), val)
+#define this_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val)
+#define this_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val)
+#define this_cpu_xor_8(pcp, val) percpu_to_op("xor", (pcp), val)
+#define this_cpu_add_return_8(pcp, val) percpu_add_return_op(pcp, val)
+#define this_cpu_xchg_8(pcp, nval) percpu_xchg_op(pcp, nval)
+#define this_cpu_cmpxchg_8(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
+
+/*
+ * Pretty complex macro to generate cmpxchg16 instruction. The instruction
+ * is not supported on early AMD64 processors so we must be able to emulate
+ * it in software. The address used in the cmpxchg16 instruction must be
+ * aligned to a 16 byte boundary.
+ */
+#define percpu_cmpxchg16b_double(pcp1, pcp2, o1, o2, n1, n2) \
+({ \
+ bool __ret; \
+ typeof(pcp1) __o1 = (o1), __n1 = (n1); \
+ typeof(pcp2) __o2 = (o2), __n2 = (n2); \
+ alternative_io("leaq %P1,%%rsi\n\tcall this_cpu_cmpxchg16b_emu\n\t", \
+ "cmpxchg16b " __percpu_arg(1) "\n\tsetz %0\n\t", \
+ X86_FEATURE_CX16, \
+ ASM_OUTPUT2("=a" (__ret), "+m" (pcp1), \
+ "+m" (pcp2), "+d" (__o2)), \
+ "b" (__n1), "c" (__n2), "a" (__o1) : "rsi"); \
+ __ret; \
+})
+
+#define __this_cpu_cmpxchg_double_8 percpu_cmpxchg16b_double
+#define this_cpu_cmpxchg_double_8 percpu_cmpxchg16b_double
+
+#endif
+
+/* This is not atomic against other CPUs -- CPU preemption needs to be off */
+#define x86_test_and_clear_bit_percpu(bit, var) \
+({ \
+ int old__; \
+ asm volatile("btr %2,"__percpu_arg(1)"\n\tsbbl %0,%0" \
+ : "=r" (old__), "+m" (var) \
+ : "dIr" (bit)); \
+ old__; \
+})
+
+static __always_inline int x86_this_cpu_constant_test_bit(unsigned int nr,
+ const unsigned long __percpu *addr)
+{
+ unsigned long __percpu *a = (unsigned long *)addr + nr / BITS_PER_LONG;
+
+ return ((1UL << (nr % BITS_PER_LONG)) & percpu_read(*a)) != 0;
+}
+
+static inline int x86_this_cpu_variable_test_bit(int nr,
+ const unsigned long __percpu *addr)
+{
+ int oldbit;
+
+ asm volatile("bt "__percpu_arg(2)",%1\n\t"
+ "sbb %0,%0"
+ : "=r" (oldbit)
+ : "m" (*(unsigned long *)addr), "Ir" (nr));
+
+ return oldbit;
+}
+
+#define x86_this_cpu_test_bit(nr, addr) \
+ (__builtin_constant_p((nr)) \
+ ? x86_this_cpu_constant_test_bit((nr), (addr)) \
+ : x86_this_cpu_variable_test_bit((nr), (addr)))
+
+
+#include <asm-generic/percpu.h>
+
+/* We can use this directly for local CPU (faster). */
+DECLARE_PER_CPU(unsigned long, this_cpu_off);
+
+#endif /* !__ASSEMBLY__ */
+
+#ifdef CONFIG_SMP
+
+/*
+ * Define the "EARLY_PER_CPU" macros. These are used for some per_cpu
+ * variables that are initialized and accessed before there are per_cpu
+ * areas allocated.
+ */
+
+#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
+ DEFINE_PER_CPU(_type, _name) = _initvalue; \
+ __typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \
+ { [0 ... NR_CPUS-1] = _initvalue }; \
+ __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
+
+#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
+ EXPORT_PER_CPU_SYMBOL(_name)
+
+#define DECLARE_EARLY_PER_CPU(_type, _name) \
+ DECLARE_PER_CPU(_type, _name); \
+ extern __typeof__(_type) *_name##_early_ptr; \
+ extern __typeof__(_type) _name##_early_map[]
+
+#define early_per_cpu_ptr(_name) (_name##_early_ptr)
+#define early_per_cpu_map(_name, _idx) (_name##_early_map[_idx])
+#define early_per_cpu(_name, _cpu) \
+ *(early_per_cpu_ptr(_name) ? \
+ &early_per_cpu_ptr(_name)[_cpu] : \
+ &per_cpu(_name, _cpu))
+
+#else /* !CONFIG_SMP */
+#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
+ DEFINE_PER_CPU(_type, _name) = _initvalue
+
+#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
+ EXPORT_PER_CPU_SYMBOL(_name)
+
+#define DECLARE_EARLY_PER_CPU(_type, _name) \
+ DECLARE_PER_CPU(_type, _name)
+
+#define early_per_cpu(_name, _cpu) per_cpu(_name, _cpu)
+#define early_per_cpu_ptr(_name) NULL
+/* no early_per_cpu_map() */
+
+#endif /* !CONFIG_SMP */
+
+#endif /* _ASM_X86_PERCPU_H */