diff options
Diffstat (limited to 'include/asm-x86/percpu.h')
-rw-r--r-- | include/asm-x86/percpu.h | 145 |
1 files changed, 141 insertions, 4 deletions
diff --git a/include/asm-x86/percpu.h b/include/asm-x86/percpu.h index a1aaad274cca..0dec00f27eb4 100644 --- a/include/asm-x86/percpu.h +++ b/include/asm-x86/percpu.h @@ -1,5 +1,142 @@ -#ifdef CONFIG_X86_32 -# include "percpu_32.h" -#else -# include "percpu_64.h" +#ifndef _ASM_X86_PERCPU_H_ +#define _ASM_X86_PERCPU_H_ + +#ifdef CONFIG_X86_64 +#include <linux/compiler.h> + +/* Same as asm-generic/percpu.h, except that we store the per cpu offset + in the PDA. Longer term the PDA and every per cpu variable + should be just put into a single section and referenced directly + from %gs */ + +#ifdef CONFIG_SMP +#include <asm/pda.h> + +#define __per_cpu_offset(cpu) (cpu_pda(cpu)->data_offset) +#define __my_cpu_offset read_pda(data_offset) + +#define per_cpu_offset(x) (__per_cpu_offset(x)) + #endif +#include <asm-generic/percpu.h> + +DECLARE_PER_CPU(struct x8664_pda, pda); + +#else /* CONFIG_X86_64 */ + +#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) \ + movl %fs:per_cpu__##this_cpu_off, reg; \ + lea per_cpu__##var(reg), reg +#define PER_CPU_VAR(var) %fs:per_cpu__##var +#else /* ! SMP */ +#define PER_CPU(var, reg) \ + movl $per_cpu__##var, reg +#define PER_CPU_VAR(var) per_cpu__##var +#endif /* SMP */ + +#else /* ...!ASSEMBLY */ + +/* + * PER_CPU finds an address of a per-cpu variable. + * + * Args: + * var - variable name + * cpu - 32bit register containing the current CPU number + * + * The resulting address is stored in the "cpu" argument. + * + * Example: + * PER_CPU(cpu_gdt_descr, %ebx) + */ +#ifdef CONFIG_SMP + +#define __my_cpu_offset x86_read_percpu(this_cpu_off) + +/* fs segment starts at (positive) offset == __per_cpu_offset[cpu] */ +#define __percpu_seg "%%fs:" + +#else /* !SMP */ + +#define __percpu_seg "" + +#endif /* SMP */ + +#include <asm-generic/percpu.h> + +/* We can use this directly for local CPU (faster). */ +DECLARE_PER_CPU(unsigned long, this_cpu_off); + +/* 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) T__; \ + if (0) { T__ tmp__; tmp__ = (val); } \ + switch (sizeof(var)) { \ + case 1: \ + asm(op "b %1,"__percpu_seg"%0" \ + : "+m" (var) \ + :"ri" ((T__)val)); \ + break; \ + case 2: \ + asm(op "w %1,"__percpu_seg"%0" \ + : "+m" (var) \ + :"ri" ((T__)val)); \ + break; \ + case 4: \ + asm(op "l %1,"__percpu_seg"%0" \ + : "+m" (var) \ + :"ri" ((T__)val)); \ + break; \ + default: __bad_percpu_size(); \ + } \ + } while (0) + +#define percpu_from_op(op,var) \ + ({ \ + typeof(var) ret__; \ + switch (sizeof(var)) { \ + case 1: \ + asm(op "b "__percpu_seg"%1,%0" \ + : "=r" (ret__) \ + : "m" (var)); \ + break; \ + case 2: \ + asm(op "w "__percpu_seg"%1,%0" \ + : "=r" (ret__) \ + : "m" (var)); \ + break; \ + case 4: \ + asm(op "l "__percpu_seg"%1,%0" \ + : "=r" (ret__) \ + : "m" (var)); \ + break; \ + default: __bad_percpu_size(); \ + } \ + ret__; }) + +#define x86_read_percpu(var) percpu_from_op("mov", per_cpu__##var) +#define x86_write_percpu(var,val) percpu_to_op("mov", per_cpu__##var, val) +#define x86_add_percpu(var,val) percpu_to_op("add", per_cpu__##var, val) +#define x86_sub_percpu(var,val) percpu_to_op("sub", per_cpu__##var, val) +#define x86_or_percpu(var,val) percpu_to_op("or", per_cpu__##var, val) +#endif /* !__ASSEMBLY__ */ +#endif /* !CONFIG_X86_64 */ +#endif /* _ASM_X86_PERCPU_H_ */ |