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Diffstat (limited to 'kernel/arch/x86/include/asm/percpu.h')
| -rw-r--r-- | kernel/arch/x86/include/asm/percpu.h | 620 |
1 files changed, 620 insertions, 0 deletions
diff --git a/kernel/arch/x86/include/asm/percpu.h b/kernel/arch/x86/include/asm/percpu.h new file mode 100644 index 000000000..e0ba66ca6 --- /dev/null +++ b/kernel/arch/x86/include/asm/percpu.h @@ -0,0 +1,620 @@ +#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(op "b "__percpu_arg(1)",%0" \ + : "=q" (pfo_ret__) \ + : "m" (var)); \ + break; \ + case 2: \ + asm(op "w "__percpu_arg(1)",%0" \ + : "=r" (pfo_ret__) \ + : "m" (var)); \ + break; \ + case 4: \ + asm(op "l "__percpu_arg(1)",%0" \ + : "=r" (pfo_ret__) \ + : "m" (var)); \ + break; \ + case 8: \ + asm(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)"\n\tsetz %0\n\t" \ + : "=a" (__ret), "+m" (pcp1), "+m" (pcp2), "+d" (__o2) \ + : "b" (__n1), "c" (__n2), "a" (__o1)); \ + __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 + +/* 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; + +#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 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_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 */ |