Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h
Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h to simplify disintegration of asm/system.h. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
This commit is contained in:
David Howells
parent
885df91ca3
commit
b4816afa39
2 changed files with 80 additions and 77 deletions
|
|
@ -1,16 +1,87 @@
|
|||
/*
|
||||
* Generic UP xchg and cmpxchg using interrupt disablement. Does not
|
||||
* support SMP.
|
||||
*/
|
||||
|
||||
#ifndef __ASM_GENERIC_CMPXCHG_H
|
||||
#define __ASM_GENERIC_CMPXCHG_H
|
||||
|
||||
/*
|
||||
* Generic cmpxchg
|
||||
*
|
||||
* Uses the local cmpxchg. Does not support SMP.
|
||||
*/
|
||||
#ifdef CONFIG_SMP
|
||||
#error "Cannot use generic cmpxchg on SMP"
|
||||
#endif
|
||||
|
||||
#include <asm-generic/cmpxchg-local.h>
|
||||
#include <linux/irqflags.h>
|
||||
|
||||
#ifndef xchg
|
||||
|
||||
/*
|
||||
* This function doesn't exist, so you'll get a linker error if
|
||||
* something tries to do an invalidly-sized xchg().
|
||||
*/
|
||||
extern void __xchg_called_with_bad_pointer(void);
|
||||
|
||||
static inline
|
||||
unsigned long __xchg(unsigned long x, volatile void *ptr, int size)
|
||||
{
|
||||
unsigned long ret, flags;
|
||||
|
||||
switch (size) {
|
||||
case 1:
|
||||
#ifdef __xchg_u8
|
||||
return __xchg_u8(x, ptr);
|
||||
#else
|
||||
local_irq_save(flags);
|
||||
ret = *(volatile u8 *)ptr;
|
||||
*(volatile u8 *)ptr = x;
|
||||
local_irq_restore(flags);
|
||||
return ret;
|
||||
#endif /* __xchg_u8 */
|
||||
|
||||
case 2:
|
||||
#ifdef __xchg_u16
|
||||
return __xchg_u16(x, ptr);
|
||||
#else
|
||||
local_irq_save(flags);
|
||||
ret = *(volatile u16 *)ptr;
|
||||
*(volatile u16 *)ptr = x;
|
||||
local_irq_restore(flags);
|
||||
return ret;
|
||||
#endif /* __xchg_u16 */
|
||||
|
||||
case 4:
|
||||
#ifdef __xchg_u32
|
||||
return __xchg_u32(x, ptr);
|
||||
#else
|
||||
local_irq_save(flags);
|
||||
ret = *(volatile u32 *)ptr;
|
||||
*(volatile u32 *)ptr = x;
|
||||
local_irq_restore(flags);
|
||||
return ret;
|
||||
#endif /* __xchg_u32 */
|
||||
|
||||
#ifdef CONFIG_64BIT
|
||||
case 8:
|
||||
#ifdef __xchg_u64
|
||||
return __xchg_u64(x, ptr);
|
||||
#else
|
||||
local_irq_save(flags);
|
||||
ret = *(volatile u64 *)ptr;
|
||||
*(volatile u64 *)ptr = x;
|
||||
local_irq_restore(flags);
|
||||
return ret;
|
||||
#endif /* __xchg_u64 */
|
||||
#endif /* CONFIG_64BIT */
|
||||
|
||||
default:
|
||||
__xchg_called_with_bad_pointer();
|
||||
return x;
|
||||
}
|
||||
}
|
||||
|
||||
#define xchg(ptr, x) \
|
||||
((__typeof__(*(ptr))) __xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
|
||||
|
||||
#endif /* xchg */
|
||||
|
||||
/*
|
||||
* Atomic compare and exchange.
|
||||
|
|
@ -18,7 +89,9 @@
|
|||
* Do not define __HAVE_ARCH_CMPXCHG because we want to use it to check whether
|
||||
* a cmpxchg primitive faster than repeated local irq save/restore exists.
|
||||
*/
|
||||
#include <asm-generic/cmpxchg-local.h>
|
||||
|
||||
#define cmpxchg(ptr, o, n) cmpxchg_local((ptr), (o), (n))
|
||||
#define cmpxchg64(ptr, o, n) cmpxchg64_local((ptr), (o), (n))
|
||||
|
||||
#endif
|
||||
#endif /* __ASM_GENERIC_CMPXCHG_H */
|
||||
|
|
|
|||
|
|
@ -17,7 +17,6 @@
|
|||
#ifndef __ASSEMBLY__
|
||||
|
||||
#include <linux/types.h>
|
||||
#include <linux/irqflags.h>
|
||||
|
||||
#include <asm/barrier.h>
|
||||
#include <asm/cmpxchg.h>
|
||||
|
|
@ -34,75 +33,6 @@ extern struct task_struct *__switch_to(struct task_struct *,
|
|||
|
||||
#define arch_align_stack(x) (x)
|
||||
|
||||
/*
|
||||
* we make sure local_irq_enable() doesn't cause priority inversion
|
||||
*/
|
||||
|
||||
/* This function doesn't exist, so you'll get a linker error
|
||||
* if something tries to do an invalid xchg(). */
|
||||
extern void __xchg_called_with_bad_pointer(void);
|
||||
|
||||
static inline
|
||||
unsigned long __xchg(unsigned long x, volatile void *ptr, int size)
|
||||
{
|
||||
unsigned long ret, flags;
|
||||
|
||||
switch (size) {
|
||||
case 1:
|
||||
#ifdef __xchg_u8
|
||||
return __xchg_u8(x, ptr);
|
||||
#else
|
||||
local_irq_save(flags);
|
||||
ret = *(volatile u8 *)ptr;
|
||||
*(volatile u8 *)ptr = x;
|
||||
local_irq_restore(flags);
|
||||
return ret;
|
||||
#endif /* __xchg_u8 */
|
||||
|
||||
case 2:
|
||||
#ifdef __xchg_u16
|
||||
return __xchg_u16(x, ptr);
|
||||
#else
|
||||
local_irq_save(flags);
|
||||
ret = *(volatile u16 *)ptr;
|
||||
*(volatile u16 *)ptr = x;
|
||||
local_irq_restore(flags);
|
||||
return ret;
|
||||
#endif /* __xchg_u16 */
|
||||
|
||||
case 4:
|
||||
#ifdef __xchg_u32
|
||||
return __xchg_u32(x, ptr);
|
||||
#else
|
||||
local_irq_save(flags);
|
||||
ret = *(volatile u32 *)ptr;
|
||||
*(volatile u32 *)ptr = x;
|
||||
local_irq_restore(flags);
|
||||
return ret;
|
||||
#endif /* __xchg_u32 */
|
||||
|
||||
#ifdef CONFIG_64BIT
|
||||
case 8:
|
||||
#ifdef __xchg_u64
|
||||
return __xchg_u64(x, ptr);
|
||||
#else
|
||||
local_irq_save(flags);
|
||||
ret = *(volatile u64 *)ptr;
|
||||
*(volatile u64 *)ptr = x;
|
||||
local_irq_restore(flags);
|
||||
return ret;
|
||||
#endif /* __xchg_u64 */
|
||||
#endif /* CONFIG_64BIT */
|
||||
|
||||
default:
|
||||
__xchg_called_with_bad_pointer();
|
||||
return x;
|
||||
}
|
||||
}
|
||||
|
||||
#define xchg(ptr, x) \
|
||||
((__typeof__(*(ptr))) __xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
|
||||
|
||||
#endif /* !__ASSEMBLY__ */
|
||||
|
||||
#endif /* __ASM_GENERIC_SYSTEM_H */
|
||||
|
|
|
|||
Loading…
Reference in a new issue