#ifndef _ASM_IA64_CMPXCHG_H #define _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 *)ptr, x); \ break; \ \ case 2: \ __xchg_result = ia64_xchg2((__u16 *)ptr, x); \ break; \ \ case 4: \ __xchg_result = ia64_xchg4((__u32 *)ptr, x); \ break; \ \ case 8: \ __xchg_result = ia64_xchg8((__u64 *)ptr, x); \ break; \ default: \ ia64_xchg_called_with_bad_pointer(); \ } \ __xchg_result; \ }) #define xchg(ptr, x) \ ((__typeof__(*(ptr))) __xchg((unsigned long) (x), (ptr), sizeof(*(ptr)))) /* * 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 /* * 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) (old); \ break; \ case 2: \ _o_ = (__u16) (long) (old); \ break; \ case 4: \ _o_ = (__u32) (long) (old); \ break; \ case 8: \ _o_ = (__u64) (long) (old); \ break; \ default: \ break; \ } \ switch (size) { \ case 1: \ _r_ = ia64_cmpxchg1_##sem((__u8 *) ptr, new, _o_); \ break; \ \ case 2: \ _r_ = ia64_cmpxchg2_##sem((__u16 *) ptr, new, _o_); \ break; \ \ case 4: \ _r_ = ia64_cmpxchg4_##sem((__u32 *) ptr, new, _o_); \ break; \ \ case 8: \ _r_ = ia64_cmpxchg8_##sem((__u64 *) ptr, new, _o_); \ break; \ \ default: \ _r_ = ia64_cmpxchg_called_with_bad_pointer(); \ break; \ } \ (__typeof__(old)) _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 :-( */ /* 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 #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 /* _ASM_IA64_CMPXCHG_H */