diff options
Diffstat (limited to 'arch/ia64/include/uapi/asm/cmpxchg.h')
| -rw-r--r-- | arch/ia64/include/uapi/asm/cmpxchg.h | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/arch/ia64/include/uapi/asm/cmpxchg.h b/arch/ia64/include/uapi/asm/cmpxchg.h new file mode 100644 index 000000000..ca2e02685 --- /dev/null +++ b/arch/ia64/include/uapi/asm/cmpxchg.h @@ -0,0 +1,159 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef _UAPI_ASM_IA64_CMPXCHG_H +#define _UAPI_ASM_IA64_CMPXCHG_H + +/* + * Compare/Exchange, forked from asm/intrinsics.h + * which was: + * + * Copyright (C) 2002-2003 Hewlett-Packard Co + * David Mosberger-Tang <davidm@hpl.hp.com> + */ + +#ifndef __ASSEMBLY__ + +#include <linux/types.h> +/* include compiler specific intrinsics */ +#include <asm/ia64regs.h> +#ifdef __INTEL_COMPILER +# include <asm/intel_intrin.h> +#else +# include <asm/gcc_intrin.h> +#endif + +/* + * This function doesn't exist, so you'll get a linker error if + * something tries to do an invalid xchg(). + */ +extern void ia64_xchg_called_with_bad_pointer(void); + +#define __xchg(x, ptr, size) \ +({ \ + unsigned long __xchg_result; \ + \ + switch (size) { \ + case 1: \ + __xchg_result = ia64_xchg1((__u8 __force *)ptr, x); \ + break; \ + \ + case 2: \ + __xchg_result = ia64_xchg2((__u16 __force *)ptr, x); \ + break; \ + \ + case 4: \ + __xchg_result = ia64_xchg4((__u32 __force *)ptr, x); \ + break; \ + \ + case 8: \ + __xchg_result = ia64_xchg8((__u64 __force *)ptr, x); \ + break; \ + default: \ + ia64_xchg_called_with_bad_pointer(); \ + } \ + (__typeof__ (*(ptr)) __force) __xchg_result; \ +}) + +#ifndef __KERNEL__ +#define xchg(ptr, x) \ +({(__typeof__(*(ptr))) __xchg((unsigned long) (x), (ptr), sizeof(*(ptr)));}) +#endif + +/* + * 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. + */ + +/* + * This function doesn't exist, so you'll get a linker error + * if something tries to do an invalid cmpxchg(). + */ +extern long ia64_cmpxchg_called_with_bad_pointer(void); + +#define ia64_cmpxchg(sem, ptr, old, new, size) \ +({ \ + __u64 _o_, _r_; \ + \ + switch (size) { \ + case 1: \ + _o_ = (__u8) (long __force) (old); \ + break; \ + case 2: \ + _o_ = (__u16) (long __force) (old); \ + break; \ + case 4: \ + _o_ = (__u32) (long __force) (old); \ + break; \ + case 8: \ + _o_ = (__u64) (long __force) (old); \ + break; \ + default: \ + break; \ + } \ + switch (size) { \ + case 1: \ + _r_ = ia64_cmpxchg1_##sem((__u8 __force *) ptr, new, _o_); \ + break; \ + \ + case 2: \ + _r_ = ia64_cmpxchg2_##sem((__u16 __force *) ptr, new, _o_); \ + break; \ + \ + case 4: \ + _r_ = ia64_cmpxchg4_##sem((__u32 __force *) ptr, new, _o_); \ + break; \ + \ + case 8: \ + _r_ = ia64_cmpxchg8_##sem((__u64 __force *) ptr, new, _o_); \ + break; \ + \ + default: \ + _r_ = ia64_cmpxchg_called_with_bad_pointer(); \ + break; \ + } \ + (__typeof__(old) __force) _r_; \ +}) + +#define cmpxchg_acq(ptr, o, n) \ + ia64_cmpxchg(acq, (ptr), (o), (n), sizeof(*(ptr))) +#define cmpxchg_rel(ptr, o, n) \ + ia64_cmpxchg(rel, (ptr), (o), (n), sizeof(*(ptr))) + +/* + * Worse still - early processor implementations actually just ignored + * the acquire/release and did a full fence all the time. Unfortunately + * this meant a lot of badly written code that used .acq when they really + * wanted .rel became legacy out in the wild - so when we made a cpu + * that strictly did the .acq or .rel ... all that code started breaking - so + * we had to back-pedal and keep the "legacy" behavior of a full fence :-( + */ + +#ifndef __KERNEL__ +/* for compatibility with other platforms: */ +#define cmpxchg(ptr, o, n) cmpxchg_acq((ptr), (o), (n)) +#define cmpxchg64(ptr, o, n) cmpxchg_acq((ptr), (o), (n)) + +#define cmpxchg_local cmpxchg +#define cmpxchg64_local cmpxchg64 +#endif + +#ifdef CONFIG_IA64_DEBUG_CMPXCHG +# define CMPXCHG_BUGCHECK_DECL int _cmpxchg_bugcheck_count = 128; +# define CMPXCHG_BUGCHECK(v) \ +do { \ + if (_cmpxchg_bugcheck_count-- <= 0) { \ + void *ip; \ + extern int _printk(const char *fmt, ...); \ + ip = (void *) ia64_getreg(_IA64_REG_IP); \ + _printk("CMPXCHG_BUGCHECK: stuck at %p on word %p\n", ip, (v));\ + break; \ + } \ +} while (0) +#else /* !CONFIG_IA64_DEBUG_CMPXCHG */ +# define CMPXCHG_BUGCHECK_DECL +# define CMPXCHG_BUGCHECK(v) +#endif /* !CONFIG_IA64_DEBUG_CMPXCHG */ + +#endif /* !__ASSEMBLY__ */ + +#endif /* _UAPI_ASM_IA64_CMPXCHG_H */ |