percpu: make x86 addr <-> pcpu ptr conversion macros generic

Impact: generic addr <-> pcpu ptr conversion macros

There's nothing arch specific about x86 __addr_to_pcpu_ptr() and
__pcpu_ptr_to_addr().  With proper __per_cpu_load and __per_cpu_start
defined, they'll do the right thing regardless of actual layout.

Move these macros from arch/x86/include/asm/percpu.h to mm/percpu.c
and allow archs to override it as necessary.

Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Tejun Heo 2009-03-10 16:27:48 +09:00
parent 19390c4d03
commit e01009833e
2 changed files with 15 additions and 9 deletions

View File

@ -43,14 +43,6 @@
#else /* ...!ASSEMBLY */
#include <linux/stringify.h>
#include <asm/sections.h>
#define __addr_to_pcpu_ptr(addr) \
(void *)((unsigned long)(addr) - (unsigned long)pcpu_base_addr \
+ (unsigned long)__per_cpu_start)
#define __pcpu_ptr_to_addr(ptr) \
(void *)((unsigned long)(ptr) + (unsigned long)pcpu_base_addr \
- (unsigned long)__per_cpu_start)
#ifdef CONFIG_SMP
#define __percpu_arg(x) "%%"__stringify(__percpu_seg)":%P" #x

View File

@ -46,7 +46,8 @@
* - define CONFIG_HAVE_DYNAMIC_PER_CPU_AREA
*
* - define __addr_to_pcpu_ptr() and __pcpu_ptr_to_addr() to translate
* regular address to percpu pointer and back
* regular address to percpu pointer and back if they need to be
* different from the default
*
* - use pcpu_setup_first_chunk() during percpu area initialization to
* setup the first chunk containing the kernel static percpu area
@ -67,11 +68,24 @@
#include <linux/workqueue.h>
#include <asm/cacheflush.h>
#include <asm/sections.h>
#include <asm/tlbflush.h>
#define PCPU_SLOT_BASE_SHIFT 5 /* 1-31 shares the same slot */
#define PCPU_DFL_MAP_ALLOC 16 /* start a map with 16 ents */
/* default addr <-> pcpu_ptr mapping, override in asm/percpu.h if necessary */
#ifndef __addr_to_pcpu_ptr
#define __addr_to_pcpu_ptr(addr) \
(void *)((unsigned long)(addr) - (unsigned long)pcpu_base_addr \
+ (unsigned long)__per_cpu_start)
#endif
#ifndef __pcpu_ptr_to_addr
#define __pcpu_ptr_to_addr(ptr) \
(void *)((unsigned long)(ptr) + (unsigned long)pcpu_base_addr \
- (unsigned long)__per_cpu_start)
#endif
struct pcpu_chunk {
struct list_head list; /* linked to pcpu_slot lists */
struct rb_node rb_node; /* key is chunk->vm->addr */