77ef50a522
This patch is the result of an automatic script that consolidates the format of all the headers in include/asm-x86/. The format: 1. No leading underscore. Names with leading underscores are reserved. 2. Pathname components are separated by two underscores. So we can distinguish between mm_types.h and mm/types.h. 3. Everything except letters and numbers are turned into single underscores. Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
186 lines
4.5 KiB
C
186 lines
4.5 KiB
C
#ifndef ASM_X86__CMPXCHG_64_H
|
|
#define ASM_X86__CMPXCHG_64_H
|
|
|
|
#include <asm/alternative.h> /* Provides LOCK_PREFIX */
|
|
|
|
#define xchg(ptr, v) ((__typeof__(*(ptr)))__xchg((unsigned long)(v), \
|
|
(ptr), sizeof(*(ptr))))
|
|
|
|
#define __xg(x) ((volatile long *)(x))
|
|
|
|
static inline void set_64bit(volatile unsigned long *ptr, unsigned long val)
|
|
{
|
|
*ptr = val;
|
|
}
|
|
|
|
#define _set_64bit set_64bit
|
|
|
|
/*
|
|
* Note: no "lock" prefix even on SMP: xchg always implies lock anyway
|
|
* Note 2: xchg has side effect, so that attribute volatile is necessary,
|
|
* but generally the primitive is invalid, *ptr is output argument. --ANK
|
|
*/
|
|
static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
|
|
int size)
|
|
{
|
|
switch (size) {
|
|
case 1:
|
|
asm volatile("xchgb %b0,%1"
|
|
: "=q" (x)
|
|
: "m" (*__xg(ptr)), "0" (x)
|
|
: "memory");
|
|
break;
|
|
case 2:
|
|
asm volatile("xchgw %w0,%1"
|
|
: "=r" (x)
|
|
: "m" (*__xg(ptr)), "0" (x)
|
|
: "memory");
|
|
break;
|
|
case 4:
|
|
asm volatile("xchgl %k0,%1"
|
|
: "=r" (x)
|
|
: "m" (*__xg(ptr)), "0" (x)
|
|
: "memory");
|
|
break;
|
|
case 8:
|
|
asm volatile("xchgq %0,%1"
|
|
: "=r" (x)
|
|
: "m" (*__xg(ptr)), "0" (x)
|
|
: "memory");
|
|
break;
|
|
}
|
|
return x;
|
|
}
|
|
|
|
/*
|
|
* Atomic compare and exchange. Compare OLD with MEM, if identical,
|
|
* store NEW in MEM. Return the initial value in MEM. Success is
|
|
* indicated by comparing RETURN with OLD.
|
|
*/
|
|
|
|
#define __HAVE_ARCH_CMPXCHG 1
|
|
|
|
static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
|
|
unsigned long new, int size)
|
|
{
|
|
unsigned long prev;
|
|
switch (size) {
|
|
case 1:
|
|
asm volatile(LOCK_PREFIX "cmpxchgb %b1,%2"
|
|
: "=a"(prev)
|
|
: "q"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
case 2:
|
|
asm volatile(LOCK_PREFIX "cmpxchgw %w1,%2"
|
|
: "=a"(prev)
|
|
: "r"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
case 4:
|
|
asm volatile(LOCK_PREFIX "cmpxchgl %k1,%2"
|
|
: "=a"(prev)
|
|
: "r"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
case 8:
|
|
asm volatile(LOCK_PREFIX "cmpxchgq %1,%2"
|
|
: "=a"(prev)
|
|
: "r"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
}
|
|
return old;
|
|
}
|
|
|
|
/*
|
|
* Always use locked operations when touching memory shared with a
|
|
* hypervisor, since the system may be SMP even if the guest kernel
|
|
* isn't.
|
|
*/
|
|
static inline unsigned long __sync_cmpxchg(volatile void *ptr,
|
|
unsigned long old,
|
|
unsigned long new, int size)
|
|
{
|
|
unsigned long prev;
|
|
switch (size) {
|
|
case 1:
|
|
asm volatile("lock; cmpxchgb %b1,%2"
|
|
: "=a"(prev)
|
|
: "q"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
case 2:
|
|
asm volatile("lock; cmpxchgw %w1,%2"
|
|
: "=a"(prev)
|
|
: "r"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
case 4:
|
|
asm volatile("lock; cmpxchgl %1,%2"
|
|
: "=a"(prev)
|
|
: "r"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
}
|
|
return old;
|
|
}
|
|
|
|
static inline unsigned long __cmpxchg_local(volatile void *ptr,
|
|
unsigned long old,
|
|
unsigned long new, int size)
|
|
{
|
|
unsigned long prev;
|
|
switch (size) {
|
|
case 1:
|
|
asm volatile("cmpxchgb %b1,%2"
|
|
: "=a"(prev)
|
|
: "q"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
case 2:
|
|
asm volatile("cmpxchgw %w1,%2"
|
|
: "=a"(prev)
|
|
: "r"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
case 4:
|
|
asm volatile("cmpxchgl %k1,%2"
|
|
: "=a"(prev)
|
|
: "r"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
case 8:
|
|
asm volatile("cmpxchgq %1,%2"
|
|
: "=a"(prev)
|
|
: "r"(new), "m"(*__xg(ptr)), "0"(old)
|
|
: "memory");
|
|
return prev;
|
|
}
|
|
return old;
|
|
}
|
|
|
|
#define cmpxchg(ptr, o, n) \
|
|
((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \
|
|
(unsigned long)(n), sizeof(*(ptr))))
|
|
#define cmpxchg64(ptr, o, n) \
|
|
({ \
|
|
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
|
|
cmpxchg((ptr), (o), (n)); \
|
|
})
|
|
#define cmpxchg_local(ptr, o, n) \
|
|
((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
|
|
(unsigned long)(n), \
|
|
sizeof(*(ptr))))
|
|
#define sync_cmpxchg(ptr, o, n) \
|
|
((__typeof__(*(ptr)))__sync_cmpxchg((ptr), (unsigned long)(o), \
|
|
(unsigned long)(n), \
|
|
sizeof(*(ptr))))
|
|
#define cmpxchg64_local(ptr, o, n) \
|
|
({ \
|
|
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
|
|
cmpxchg_local((ptr), (o), (n)); \
|
|
})
|
|
|
|
#endif /* ASM_X86__CMPXCHG_64_H */
|