kernel-fxtec-pro1x/include/asm-x86/percpu.h
Marcin Slusarz c6a92a2501 x86, percpu: silence section mismatch warnings related to EARLY_PER_CPU variables
Quoting Mike Travis in "x86: cleanup early per cpu variables/accesses v4"
(23ca4bba3e):

    The DEFINE macro defines the per_cpu variable as well as the early
    map and pointer.  It also initializes the per_cpu variable and map
    elements to "_initvalue".  The early_* macros provide access to
    the initial map (usually setup during system init) and the early
    pointer.  This pointer is initialized to point to the early map
    but is then NULL'ed when the actual per_cpu areas are setup.  After
    that the per_cpu variable is the correct access to the variable.

As these variables are NULL'ed before __init sections are dropped
(in setup_per_cpu_maps), they can be safely annotated as __ref.

This change silences following section mismatch warnings:

WARNING: vmlinux.o(.data+0x46c0): Section mismatch in reference from the variable x86_cpu_to_apicid_early_ptr to the variable .init.data:x86_cpu_to_apicid_early_map
The variable x86_cpu_to_apicid_early_ptr references
the variable __initdata x86_cpu_to_apicid_early_map
If the reference is valid then annotate the
variable with __init* (see linux/init.h) or name the variable:
*driver, *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console,

WARNING: vmlinux.o(.data+0x46c8): Section mismatch in reference from the variable x86_bios_cpu_apicid_early_ptr to the variable .init.data:x86_bios_cpu_apicid_early_map
The variable x86_bios_cpu_apicid_early_ptr references
the variable __initdata x86_bios_cpu_apicid_early_map
If the reference is valid then annotate the
variable with __init* (see linux/init.h) or name the variable:
*driver, *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console,

WARNING: vmlinux.o(.data+0x46d0): Section mismatch in reference from the variable x86_cpu_to_node_map_early_ptr to the variable .init.data:x86_cpu_to_node_map_early_map
The variable x86_cpu_to_node_map_early_ptr references
the variable __initdata x86_cpu_to_node_map_early_map
If the reference is valid then annotate the
variable with __init* (see linux/init.h) or name the variable:
*driver, *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console,

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-18 09:10:55 +02:00

218 lines
5.7 KiB
C

#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);
/*
* 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_ */