[deliverable/linux.git] / arch / x86 / include / asm / percpu.h

#ifndef _ASM_X86_PERCPU_H
#define _ASM_X86_PERCPU_H

#ifndef __ASSEMBLY__
#ifdef CONFIG_X86_64
extern void load_pda_offset(int cpu);
#else
static inline void load_pda_offset(int cpu) { }
#endif
#endif

#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);

/*
 * These are supposed to be implemented as a single instruction which
 * operates on the per-cpu data base segment.  x86-64 doesn't have
 * that yet, so this is a fairly inefficient workaround for the
 * meantime.  The single instruction is atomic with respect to
 * preemption and interrupts, so we need to explicitly disable
 * interrupts here to achieve the same effect.  However, because it
 * can be used from within interrupt-disable/enable, we can't actually
 * disable interrupts; disabling preemption is enough.
 */
#define x86_read_percpu(var)						\
	({								\
		typeof(per_cpu_var(var)) __tmp;				\
		preempt_disable();					\
		__tmp = __get_cpu_var(var);				\
		preempt_enable();					\
		__tmp;							\
	})

#define x86_write_percpu(var, val)					\
	do {								\
		preempt_disable();					\
		__get_cpu_var(var) = (val);				\
		preempt_enable();					\
	} while(0)

#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 */

#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 */
Commit	Line	Data
1965aae3 PA	1	#ifndef _ASM_X86_PERCPU_H
1965aae3 PA	2	#define _ASM_X86_PERCPU_H
3334052a	3
1a51e3a0 TH	4	#ifndef __ASSEMBLY__
	5	#ifdef CONFIG_X86_64
	6	extern void load_pda_offset(int cpu);
	7	#else
	8	static inline void load_pda_offset(int cpu) { }
	9	#endif
	10	#endif
	11
3334052a	12	#ifdef CONFIG_X86_64
	13	#include <linux/compiler.h>
	14
	15	/* Same as asm-generic/percpu.h, except that we store the per cpu offset
	16	in the PDA. Longer term the PDA and every per cpu variable
	17	should be just put into a single section and referenced directly
	18	from %gs */
	19
	20	#ifdef CONFIG_SMP
	21	#include <asm/pda.h>
	22
	23	#define __per_cpu_offset(cpu) (cpu_pda(cpu)->data_offset)
	24	#define __my_cpu_offset read_pda(data_offset)
	25
	26	#define per_cpu_offset(x) (__per_cpu_offset(x))
	27
96a388de	28	#endif
3334052a	29	#include <asm-generic/percpu.h>
	30
	31	DECLARE_PER_CPU(struct x8664_pda, pda);
	32
5b09b287 JF	33	/*
	34	* These are supposed to be implemented as a single instruction which
	35	* operates on the per-cpu data base segment. x86-64 doesn't have
	36	* that yet, so this is a fairly inefficient workaround for the
	37	* meantime. The single instruction is atomic with respect to
	38	* preemption and interrupts, so we need to explicitly disable
	39	* interrupts here to achieve the same effect. However, because it
	40	* can be used from within interrupt-disable/enable, we can't actually
	41	* disable interrupts; disabling preemption is enough.
	42	*/
	43	#define x86_read_percpu(var) \
	44	({ \
	45	typeof(per_cpu_var(var)) __tmp; \
	46	preempt_disable(); \
	47	__tmp = __get_cpu_var(var); \
	48	preempt_enable(); \
	49	__tmp; \
	50	})
	51
	52	#define x86_write_percpu(var, val) \
	53	do { \
	54	preempt_disable(); \
	55	__get_cpu_var(var) = (val); \
	56	preempt_enable(); \
	57	} while(0)
	58
3334052a	59	#else /* CONFIG_X86_64 */
	60
	61	#ifdef __ASSEMBLY__
	62
	63	/*
	64	* PER_CPU finds an address of a per-cpu variable.
	65	*
	66	* Args:
	67	* var - variable name
	68	* reg - 32bit register
	69	*
	70	* The resulting address is stored in the "reg" argument.
	71	*
	72	* Example:
	73	* PER_CPU(cpu_gdt_descr, %ebx)
	74	*/
	75	#ifdef CONFIG_SMP
	76	#define PER_CPU(var, reg) \
	77	movl %fs:per_cpu__##this_cpu_off, reg; \
	78	lea per_cpu__##var(reg), reg
	79	#define PER_CPU_VAR(var) %fs:per_cpu__##var
	80	#else /* ! SMP */
	81	#define PER_CPU(var, reg) \
	82	movl $per_cpu__##var, reg
	83	#define PER_CPU_VAR(var) per_cpu__##var
	84	#endif /* SMP */
	85
	86	#else /* ...!ASSEMBLY */
	87
	88	/*
	89	* PER_CPU finds an address of a per-cpu variable.
	90	*
	91	* Args:
	92	* var - variable name
	93	* cpu - 32bit register containing the current CPU number
	94	*
	95	* The resulting address is stored in the "cpu" argument.
	96	*
	97	* Example:
	98	* PER_CPU(cpu_gdt_descr, %ebx)
	99	*/
	100	#ifdef CONFIG_SMP
	101
	102	#define __my_cpu_offset x86_read_percpu(this_cpu_off)
	103
	104	/* fs segment starts at (positive) offset == __per_cpu_offset[cpu] */
	105	#define __percpu_seg "%%fs:"
	106
	107	#else /* !SMP */
	108
	109	#define __percpu_seg ""
	110
	111	#endif /* SMP */
	112
	113	#include <asm-generic/percpu.h>
	114
	115	/* We can use this directly for local CPU (faster). */
	116	DECLARE_PER_CPU(unsigned long, this_cpu_off);
	117
	118	/* For arch-specific code, we can use direct single-insn ops (they
	119	* don't give an lvalue though). */
	120	extern void __bad_percpu_size(void);
	121
bc9e3be2 JP	122	#define percpu_to_op(op, var, val) \
	123	do { \
	124	typedef typeof(var) T__; \
	125	if (0) { \
	126	T__ tmp__; \
	127	tmp__ = (val); \
	128	} \
	129	switch (sizeof(var)) { \
	130	case 1: \
	131	asm(op "b %1,"__percpu_seg"%0" \
	132	: "+m" (var) \
	133	: "ri" ((T__)val)); \
	134	break; \
	135	case 2: \
	136	asm(op "w %1,"__percpu_seg"%0" \
	137	: "+m" (var) \
	138	: "ri" ((T__)val)); \
	139	break; \
	140	case 4: \
	141	asm(op "l %1,"__percpu_seg"%0" \
	142	: "+m" (var) \
	143	: "ri" ((T__)val)); \
	144	break; \
	145	default: __bad_percpu_size(); \
	146	} \
	147	} while (0)
	148
	149	#define percpu_from_op(op, var) \
	150	({ \
	151	typeof(var) ret__; \
	152	switch (sizeof(var)) { \
	153	case 1: \
	154	asm(op "b "__percpu_seg"%1,%0" \
	155	: "=r" (ret__) \
	156	: "m" (var)); \
	157	break; \
	158	case 2: \
	159	asm(op "w "__percpu_seg"%1,%0" \
	160	: "=r" (ret__) \
	161	: "m" (var)); \
	162	break; \
	163	case 4: \
	164	asm(op "l "__percpu_seg"%1,%0" \
	165	: "=r" (ret__) \
	166	: "m" (var)); \
	167	break; \
	168	default: __bad_percpu_size(); \
	169	} \
	170	ret__; \
	171	})
3334052a	172
3334052a	173	#define x86_read_percpu(var) percpu_from_op("mov", per_cpu__##var)
bc9e3be2 JP	174	#define x86_write_percpu(var, val) percpu_to_op("mov", per_cpu__##var, val)
	175	#define x86_add_percpu(var, val) percpu_to_op("add", per_cpu__##var, val)
	176	#define x86_sub_percpu(var, val) percpu_to_op("sub", per_cpu__##var, val)
	177	#define x86_or_percpu(var, val) percpu_to_op("or", per_cpu__##var, val)
3334052a	178	#endif /* !__ASSEMBLY__ */
3334052a	179	#endif /* !CONFIG_X86_64 */
23ca4bba MT	180
	181	#ifdef CONFIG_SMP
	182
	183	/*
	184	* Define the "EARLY_PER_CPU" macros. These are used for some per_cpu
	185	* variables that are initialized and accessed before there are per_cpu
	186	* areas allocated.
	187	*/
	188
	189	#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
	190	DEFINE_PER_CPU(_type, _name) = _initvalue; \
	191	__typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \
	192	{ [0 ... NR_CPUS-1] = _initvalue }; \
c6a92a25	193	__typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
23ca4bba MT	194
	195	#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
	196	EXPORT_PER_CPU_SYMBOL(_name)
	197
	198	#define DECLARE_EARLY_PER_CPU(_type, _name) \
	199	DECLARE_PER_CPU(_type, _name); \
	200	extern __typeof__(_type) *_name##_early_ptr; \
	201	extern __typeof__(_type) _name##_early_map[]
	202
	203	#define early_per_cpu_ptr(_name) (_name##_early_ptr)
	204	#define early_per_cpu_map(_name, _idx) (_name##_early_map[_idx])
	205	#define early_per_cpu(_name, _cpu) \
f10fcd47 TH	206	*(early_per_cpu_ptr(_name) ? \
	207	&early_per_cpu_ptr(_name)[_cpu] : \
	208	&per_cpu(_name, _cpu))
23ca4bba MT	209
	210	#else /* !CONFIG_SMP */
	211	#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
	212	DEFINE_PER_CPU(_type, _name) = _initvalue
	213
	214	#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
	215	EXPORT_PER_CPU_SYMBOL(_name)
	216
	217	#define DECLARE_EARLY_PER_CPU(_type, _name) \
	218	DECLARE_PER_CPU(_type, _name)
	219
	220	#define early_per_cpu(_name, _cpu) per_cpu(_name, _cpu)
	221	#define early_per_cpu_ptr(_name) NULL
	222	/* no early_per_cpu_map() */
	223
	224	#endif /* !CONFIG_SMP */
	225
1965aae3	226	#endif /* _ASM_X86_PERCPU_H */