Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 613 insertions, 0 deletions

diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h
new file mode 100644
index 000000000..1a19d11cf
--- /dev/null
+++ b/arch/x86/include/asm/percpu.h
@@ -0,0 +1,613 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#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		this_cpu_read(this_cpu_off)
+
+/*
+ * Compared to the generic __my_cpu_offset version, the following
+ * saves one instruction and avoids clobbering a temp register.
+ */
+#define arch_raw_cpu_ptr(ptr)				\
+({							\
+	unsigned long tcp_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 "%" #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)) ?		\
+				(int)(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)				\
+({							\
+	typeof(var) pfo_ret__;				\
+	switch (sizeof(var)) {				\
+	case 1:						\
+		asm volatile(op "b "__percpu_arg(1)",%0"\
+		    : "=q" (pfo_ret__)			\
+		    : "m" (var));			\
+		break;					\
+	case 2:						\
+		asm volatile(op "w "__percpu_arg(1)",%0"\
+		    : "=r" (pfo_ret__)			\
+		    : "m" (var));			\
+		break;					\
+	case 4:						\
+		asm volatile(op "l "__percpu_arg(1)",%0"\
+		    : "=r" (pfo_ret__)			\
+		    : "m" (var));			\
+		break;					\
+	case 8:						\
+		asm volatile(op "q "__percpu_arg(1)",%0"\
+		    : "=r" (pfo_ret__)			\
+		    : "m" (var));			\
+		break;					\
+	default: __bad_percpu_size();			\
+	}						\
+	pfo_ret__;					\
+})
+
+#define percpu_stable_op(op, var)			\
+({							\
+	typeof(var) pfo_ret__;				\
+	switch (sizeof(var)) {				\
+	case 1:						\
+		asm(op "b "__percpu_arg(P1)",%0"	\
+		    : "=q" (pfo_ret__)			\
+		    : "p" (&(var)));			\
+		break;					\
+	case 2:						\
+		asm(op "w "__percpu_arg(P1)",%0"	\
+		    : "=r" (pfo_ret__)			\
+		    : "p" (&(var)));			\
+		break;					\
+	case 4:						\
+		asm(op "l "__percpu_arg(P1)",%0"	\
+		    : "=r" (pfo_ret__)			\
+		    : "p" (&(var)));			\
+		break;					\
+	case 8:						\
+		asm(op "q "__percpu_arg(P1)",%0"	\
+		    : "=r" (pfo_ret__)			\
+		    : "p" (&(var)));			\
+		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__;							\
+})
+
+/*
+ * this_cpu_read() makes gcc load the percpu variable every time it is
+ * accessed while this_cpu_read_stable() allows the value to be cached.
+ * this_cpu_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 this_cpu_read_stable(var)	percpu_stable_op("mov", var)
+
+#define raw_cpu_read_1(pcp)		percpu_from_op("mov", pcp)
+#define raw_cpu_read_2(pcp)		percpu_from_op("mov", pcp)
+#define raw_cpu_read_4(pcp)		percpu_from_op("mov", pcp)
+
+#define raw_cpu_write_1(pcp, val)	percpu_to_op("mov", (pcp), val)
+#define raw_cpu_write_2(pcp, val)	percpu_to_op("mov", (pcp), val)
+#define raw_cpu_write_4(pcp, val)	percpu_to_op("mov", (pcp), val)
+#define raw_cpu_add_1(pcp, val)		percpu_add_op((pcp), val)
+#define raw_cpu_add_2(pcp, val)		percpu_add_op((pcp), val)
+#define raw_cpu_add_4(pcp, val)		percpu_add_op((pcp), val)
+#define raw_cpu_and_1(pcp, val)		percpu_to_op("and", (pcp), val)
+#define raw_cpu_and_2(pcp, val)		percpu_to_op("and", (pcp), val)
+#define raw_cpu_and_4(pcp, val)		percpu_to_op("and", (pcp), val)
+#define raw_cpu_or_1(pcp, val)		percpu_to_op("or", (pcp), val)
+#define raw_cpu_or_2(pcp, val)		percpu_to_op("or", (pcp), val)
+#define raw_cpu_or_4(pcp, val)		percpu_to_op("or", (pcp), val)
+#define raw_cpu_xchg_1(pcp, val)	percpu_xchg_op(pcp, val)
+#define raw_cpu_xchg_2(pcp, val)	percpu_xchg_op(pcp, val)
+#define raw_cpu_xchg_4(pcp, val)	percpu_xchg_op(pcp, val)
+
+#define this_cpu_read_1(pcp)		percpu_from_op("mov", pcp)
+#define this_cpu_read_2(pcp)		percpu_from_op("mov", pcp)
+#define this_cpu_read_4(pcp)		percpu_from_op("mov", 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_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)
+
+#define raw_cpu_add_return_1(pcp, val)		percpu_add_return_op(pcp, val)
+#define raw_cpu_add_return_2(pcp, val)		percpu_add_return_op(pcp, val)
+#define raw_cpu_add_return_4(pcp, val)		percpu_add_return_op(pcp, val)
+#define raw_cpu_cmpxchg_1(pcp, oval, nval)	percpu_cmpxchg_op(pcp, oval, nval)
+#define raw_cpu_cmpxchg_2(pcp, oval, nval)	percpu_cmpxchg_op(pcp, oval, nval)
+#define raw_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)
+
+#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)			\
+		     CC_SET(z)						\
+		     : CC_OUT(z) (__ret), "+m" (pcp1), "+m" (pcp2), "+a" (__o1), "+d" (__o2) \
+		     : "b" (__n1), "c" (__n2));				\
+	__ret;								\
+})
+
+#define raw_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 raw_cpu_read_8(pcp)			percpu_from_op("mov", pcp)
+#define raw_cpu_write_8(pcp, val)		percpu_to_op("mov", (pcp), val)
+#define raw_cpu_add_8(pcp, val)			percpu_add_op((pcp), val)
+#define raw_cpu_and_8(pcp, val)			percpu_to_op("and", (pcp), val)
+#define raw_cpu_or_8(pcp, val)			percpu_to_op("or", (pcp), val)
+#define raw_cpu_add_return_8(pcp, val)		percpu_add_return_op(pcp, val)
+#define raw_cpu_xchg_8(pcp, nval)		percpu_xchg_op(pcp, nval)
+#define raw_cpu_cmpxchg_8(pcp, oval, nval)	percpu_cmpxchg_op(pcp, oval, nval)
+
+#define this_cpu_read_8(pcp)			percpu_from_op("mov", 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_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 raw_cpu_cmpxchg_double_8	percpu_cmpxchg16b_double
+#define this_cpu_cmpxchg_double_8	percpu_cmpxchg16b_double
+
+#endif
+
+static __always_inline bool x86_this_cpu_constant_test_bit(unsigned int nr,
+                        const unsigned long __percpu *addr)
+{
+	unsigned long __percpu *a =
+		(unsigned long __percpu *)addr + nr / BITS_PER_LONG;
+
+#ifdef CONFIG_X86_64
+	return ((1UL << (nr % BITS_PER_LONG)) & raw_cpu_read_8(*a)) != 0;
+#else
+	return ((1UL << (nr % BITS_PER_LONG)) & raw_cpu_read_4(*a)) != 0;
+#endif
+}
+
+static inline bool x86_this_cpu_variable_test_bit(int nr,
+                        const unsigned long __percpu *addr)
+{
+	bool oldbit;
+
+	asm volatile("btl "__percpu_arg(2)",%1"
+			CC_SET(c)
+			: CC_OUT(c) (oldbit)
+			: "m" (*(unsigned long __percpu *)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_READ_MOSTLY(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 DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue)	\
+	DEFINE_PER_CPU_READ_MOSTLY(_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 DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name)		\
+	DECLARE_PER_CPU_READ_MOSTLY(_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 DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue)	\
+	DEFINE_PER_CPU_READ_MOSTLY(_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 DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name)		\
+	DECLARE_PER_CPU_READ_MOSTLY(_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 */