259 lines
5.5 KiB
C
259 lines
5.5 KiB
C
#ifndef __ALPHA_SYSTEM_H
|
|
#error Do not include xchg.h directly!
|
|
#else
|
|
/*
|
|
* xchg/xchg_local and cmpxchg/cmpxchg_local share the same code
|
|
* except that local version do not have the expensive memory barrier.
|
|
* So this file is included twice from asm/system.h.
|
|
*/
|
|
|
|
/*
|
|
* Atomic exchange.
|
|
* Since it can be used to implement critical sections
|
|
* it must clobber "memory" (also for interrupts in UP).
|
|
*/
|
|
|
|
static inline unsigned long
|
|
____xchg(_u8, volatile char *m, unsigned long val)
|
|
{
|
|
unsigned long ret, tmp, addr64;
|
|
|
|
__asm__ __volatile__(
|
|
" andnot %4,7,%3\n"
|
|
" insbl %1,%4,%1\n"
|
|
"1: ldq_l %2,0(%3)\n"
|
|
" extbl %2,%4,%0\n"
|
|
" mskbl %2,%4,%2\n"
|
|
" or %1,%2,%2\n"
|
|
" stq_c %2,0(%3)\n"
|
|
" beq %2,2f\n"
|
|
__ASM__MB
|
|
".subsection 2\n"
|
|
"2: br 1b\n"
|
|
".previous"
|
|
: "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
|
|
: "r" ((long)m), "1" (val) : "memory");
|
|
|
|
return ret;
|
|
}
|
|
|
|
static inline unsigned long
|
|
____xchg(_u16, volatile short *m, unsigned long val)
|
|
{
|
|
unsigned long ret, tmp, addr64;
|
|
|
|
__asm__ __volatile__(
|
|
" andnot %4,7,%3\n"
|
|
" inswl %1,%4,%1\n"
|
|
"1: ldq_l %2,0(%3)\n"
|
|
" extwl %2,%4,%0\n"
|
|
" mskwl %2,%4,%2\n"
|
|
" or %1,%2,%2\n"
|
|
" stq_c %2,0(%3)\n"
|
|
" beq %2,2f\n"
|
|
__ASM__MB
|
|
".subsection 2\n"
|
|
"2: br 1b\n"
|
|
".previous"
|
|
: "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
|
|
: "r" ((long)m), "1" (val) : "memory");
|
|
|
|
return ret;
|
|
}
|
|
|
|
static inline unsigned long
|
|
____xchg(_u32, volatile int *m, unsigned long val)
|
|
{
|
|
unsigned long dummy;
|
|
|
|
__asm__ __volatile__(
|
|
"1: ldl_l %0,%4\n"
|
|
" bis $31,%3,%1\n"
|
|
" stl_c %1,%2\n"
|
|
" beq %1,2f\n"
|
|
__ASM__MB
|
|
".subsection 2\n"
|
|
"2: br 1b\n"
|
|
".previous"
|
|
: "=&r" (val), "=&r" (dummy), "=m" (*m)
|
|
: "rI" (val), "m" (*m) : "memory");
|
|
|
|
return val;
|
|
}
|
|
|
|
static inline unsigned long
|
|
____xchg(_u64, volatile long *m, unsigned long val)
|
|
{
|
|
unsigned long dummy;
|
|
|
|
__asm__ __volatile__(
|
|
"1: ldq_l %0,%4\n"
|
|
" bis $31,%3,%1\n"
|
|
" stq_c %1,%2\n"
|
|
" beq %1,2f\n"
|
|
__ASM__MB
|
|
".subsection 2\n"
|
|
"2: br 1b\n"
|
|
".previous"
|
|
: "=&r" (val), "=&r" (dummy), "=m" (*m)
|
|
: "rI" (val), "m" (*m) : "memory");
|
|
|
|
return val;
|
|
}
|
|
|
|
/* 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 __always_inline unsigned long
|
|
____xchg(, volatile void *ptr, unsigned long x, int size)
|
|
{
|
|
switch (size) {
|
|
case 1:
|
|
return ____xchg(_u8, ptr, x);
|
|
case 2:
|
|
return ____xchg(_u16, ptr, x);
|
|
case 4:
|
|
return ____xchg(_u32, ptr, x);
|
|
case 8:
|
|
return ____xchg(_u64, ptr, x);
|
|
}
|
|
__xchg_called_with_bad_pointer();
|
|
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.
|
|
*
|
|
* The memory barrier should be placed in SMP only when we actually
|
|
* make the change. If we don't change anything (so if the returned
|
|
* prev is equal to old) then we aren't acquiring anything new and
|
|
* we don't need any memory barrier as far I can tell.
|
|
*/
|
|
|
|
static inline unsigned long
|
|
____cmpxchg(_u8, volatile char *m, unsigned char old, unsigned char new)
|
|
{
|
|
unsigned long prev, tmp, cmp, addr64;
|
|
|
|
__asm__ __volatile__(
|
|
" andnot %5,7,%4\n"
|
|
" insbl %1,%5,%1\n"
|
|
"1: ldq_l %2,0(%4)\n"
|
|
" extbl %2,%5,%0\n"
|
|
" cmpeq %0,%6,%3\n"
|
|
" beq %3,2f\n"
|
|
" mskbl %2,%5,%2\n"
|
|
" or %1,%2,%2\n"
|
|
" stq_c %2,0(%4)\n"
|
|
" beq %2,3f\n"
|
|
__ASM__MB
|
|
"2:\n"
|
|
".subsection 2\n"
|
|
"3: br 1b\n"
|
|
".previous"
|
|
: "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
|
|
: "r" ((long)m), "Ir" (old), "1" (new) : "memory");
|
|
|
|
return prev;
|
|
}
|
|
|
|
static inline unsigned long
|
|
____cmpxchg(_u16, volatile short *m, unsigned short old, unsigned short new)
|
|
{
|
|
unsigned long prev, tmp, cmp, addr64;
|
|
|
|
__asm__ __volatile__(
|
|
" andnot %5,7,%4\n"
|
|
" inswl %1,%5,%1\n"
|
|
"1: ldq_l %2,0(%4)\n"
|
|
" extwl %2,%5,%0\n"
|
|
" cmpeq %0,%6,%3\n"
|
|
" beq %3,2f\n"
|
|
" mskwl %2,%5,%2\n"
|
|
" or %1,%2,%2\n"
|
|
" stq_c %2,0(%4)\n"
|
|
" beq %2,3f\n"
|
|
__ASM__MB
|
|
"2:\n"
|
|
".subsection 2\n"
|
|
"3: br 1b\n"
|
|
".previous"
|
|
: "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
|
|
: "r" ((long)m), "Ir" (old), "1" (new) : "memory");
|
|
|
|
return prev;
|
|
}
|
|
|
|
static inline unsigned long
|
|
____cmpxchg(_u32, volatile int *m, int old, int new)
|
|
{
|
|
unsigned long prev, cmp;
|
|
|
|
__asm__ __volatile__(
|
|
"1: ldl_l %0,%5\n"
|
|
" cmpeq %0,%3,%1\n"
|
|
" beq %1,2f\n"
|
|
" mov %4,%1\n"
|
|
" stl_c %1,%2\n"
|
|
" beq %1,3f\n"
|
|
__ASM__MB
|
|
"2:\n"
|
|
".subsection 2\n"
|
|
"3: br 1b\n"
|
|
".previous"
|
|
: "=&r"(prev), "=&r"(cmp), "=m"(*m)
|
|
: "r"((long) old), "r"(new), "m"(*m) : "memory");
|
|
|
|
return prev;
|
|
}
|
|
|
|
static inline unsigned long
|
|
____cmpxchg(_u64, volatile long *m, unsigned long old, unsigned long new)
|
|
{
|
|
unsigned long prev, cmp;
|
|
|
|
__asm__ __volatile__(
|
|
"1: ldq_l %0,%5\n"
|
|
" cmpeq %0,%3,%1\n"
|
|
" beq %1,2f\n"
|
|
" mov %4,%1\n"
|
|
" stq_c %1,%2\n"
|
|
" beq %1,3f\n"
|
|
__ASM__MB
|
|
"2:\n"
|
|
".subsection 2\n"
|
|
"3: br 1b\n"
|
|
".previous"
|
|
: "=&r"(prev), "=&r"(cmp), "=m"(*m)
|
|
: "r"((long) old), "r"(new), "m"(*m) : "memory");
|
|
|
|
return prev;
|
|
}
|
|
|
|
/* This function doesn't exist, so you'll get a linker error
|
|
if something tries to do an invalid cmpxchg(). */
|
|
extern void __cmpxchg_called_with_bad_pointer(void);
|
|
|
|
static __always_inline unsigned long
|
|
____cmpxchg(, volatile void *ptr, unsigned long old, unsigned long new,
|
|
int size)
|
|
{
|
|
switch (size) {
|
|
case 1:
|
|
return ____cmpxchg(_u8, ptr, old, new);
|
|
case 2:
|
|
return ____cmpxchg(_u16, ptr, old, new);
|
|
case 4:
|
|
return ____cmpxchg(_u32, ptr, old, new);
|
|
case 8:
|
|
return ____cmpxchg(_u64, ptr, old, new);
|
|
}
|
|
__cmpxchg_called_with_bad_pointer();
|
|
return old;
|
|
}
|
|
|
|
#endif
|