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Diffstat (limited to 'erts/include/internal/libatomic_ops/ethr_atomic.h')
| -rw-r--r-- | erts/include/internal/libatomic_ops/ethr_atomic.h | 292 |
1 files changed, 292 insertions, 0 deletions
diff --git a/erts/include/internal/libatomic_ops/ethr_atomic.h b/erts/include/internal/libatomic_ops/ethr_atomic.h new file mode 100644 index 0000000000..a6eb43a0bd --- /dev/null +++ b/erts/include/internal/libatomic_ops/ethr_atomic.h @@ -0,0 +1,292 @@ +/* + * %CopyrightBegin% + * + * Copyright Ericsson AB 2010. All Rights Reserved. + * + * The contents of this file are subject to the Erlang Public License, + * Version 1.1, (the "License"); you may not use this file except in + * compliance with the License. You should have received a copy of the + * Erlang Public License along with this software. If not, it can be + * retrieved online at http://www.erlang.org/. + * + * Software distributed under the License is distributed on an "AS IS" + * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See + * the License for the specific language governing rights and limitations + * under the License. + * + * %CopyrightEnd% + */ + +/* + * Description: Native atomics ethread support using libatomic_ops + * Author: Rickard Green + */ + +#ifndef ETHR_LIBATOMIC_OPS_ATOMIC_H__ +#define ETHR_LIBATOMIC_OPS_ATOMIC_H__ + +#if !defined(ETHR_HAVE_NATIVE_ATOMICS) && defined(ETHR_HAVE_LIBATOMIC_OPS) +#define ETHR_HAVE_NATIVE_ATOMICS 1 + +#if (defined(__i386__) && !defined(ETHR_PRE_PENTIUM4_COMPAT)) \ + || defined(__x86_64__) +#define AO_USE_PENTIUM4_INSTRS +#endif + +#include "atomic_ops.h" + +/* + * libatomic_ops can be downloaded from: + * http://www.hpl.hp.com/research/linux/atomic_ops/ + * + * These operations need to be defined by libatomic_ops; + * otherwise, we won't compile: + * - AO_nop_full() + * - AO_load() + * - AO_store() + * - AO_compare_and_swap() + * + * The `AO_t' type also have to be at least as large as + * `void *' and `long' types. + */ + +#if ETHR_SIZEOF_AO_T < ETHR_SIZEOF_PTR +#error The AO_t type is too small +#endif + +typedef struct { + volatile AO_t counter; +} ethr_native_atomic_t; + +#define ETHR_MEMORY_BARRIER AO_nop_full() +#ifdef AO_HAVE_nop_write +# define ETHR_WRITE_MEMORY_BARRIER AO_nop_write() +#else +# define ETHR_WRITE_MEMORY_BARRIER ETHR_MEMORY_BARRIER +#endif +#ifdef AO_HAVE_nop_read +# define ETHR_READ_MEMORY_BARRIER AO_nop_read() +#else +# define ETHR_READ_MEMORY_BARRIER ETHR_MEMORY_BARRIER +#endif +#ifdef AO_NO_DD_ORDERING +# define ETHR_READ_DEPEND_MEMORY_BARRIER ETHR_READ_MEMORY_BARRIER +#else +# define ETHR_READ_DEPEND_MEMORY_BARRIER __asm__ __volatile__("":::"memory") +#endif + +#if defined(ETHR_TRY_INLINE_FUNCS) || defined(ETHR_AUX_IMPL__) + +static ETHR_INLINE void +ethr_native_atomic_set(ethr_native_atomic_t *var, long value) +{ + AO_store(&var->counter, (AO_t) value); +} + +static ETHR_INLINE void +ethr_native_atomic_init(ethr_native_atomic_t *var, long value) +{ + ethr_native_atomic_set(var, value); +} + +static ETHR_INLINE long +ethr_native_atomic_read(ethr_native_atomic_t *var) +{ + return (long) AO_load(&var->counter); +} + +static ETHR_INLINE long +ethr_native_atomic_add_return(ethr_native_atomic_t *var, long incr) +{ +#ifdef AO_HAVE_fetch_and_add + return ((long) AO_fetch_and_add(&var->counter, (AO_t) incr)) + incr; +#else + while (1) { + AO_t exp = AO_load(&var->counter); + AO_t new = exp + (AO_t) incr; + if (AO_compare_and_swap(&var->counter, exp, new)) + return (long) new; + } +#endif +} + +static ETHR_INLINE void +ethr_native_atomic_add(ethr_native_atomic_t *var, long incr) +{ + (void) ethr_native_atomic_add_return(var, incr); +} + +static ETHR_INLINE long +ethr_native_atomic_inc_return(ethr_native_atomic_t *var) +{ +#ifdef AO_HAVE_fetch_and_add1 + return ((long) AO_fetch_and_add1(&var->counter)) + 1; +#else + return ethr_native_atomic_add_return(var, 1); +#endif +} + +static ETHR_INLINE void +ethr_native_atomic_inc(ethr_native_atomic_t *var) +{ + (void) ethr_native_atomic_inc_return(var); +} + +static ETHR_INLINE long +ethr_native_atomic_dec_return(ethr_native_atomic_t *var) +{ +#ifdef AO_HAVE_fetch_and_sub1 + return ((long) AO_fetch_and_sub1(&var->counter)) - 1; +#else + return ethr_native_atomic_add_return(var, -1); +#endif +} + +static ETHR_INLINE void +ethr_native_atomic_dec(ethr_native_atomic_t *var) +{ + (void) ethr_native_atomic_dec_return(var); +} + +static ETHR_INLINE long +ethr_native_atomic_and_retold(ethr_native_atomic_t *var, long mask) +{ + while (1) { + AO_t exp = AO_load(&var->counter); + AO_t new = exp & ((AO_t) mask); + if (AO_compare_and_swap(&var->counter, exp, new)) + return (long) exp; + } +} + +static ETHR_INLINE long +ethr_native_atomic_or_retold(ethr_native_atomic_t *var, long mask) +{ + while (1) { + AO_t exp = AO_load(&var->counter); + AO_t new = exp | ((AO_t) mask); + if (AO_compare_and_swap(&var->counter, exp, new)) + return (long) exp; + } +} + +static ETHR_INLINE long +ethr_native_atomic_cmpxchg(ethr_native_atomic_t *var, long new, long exp) +{ + long act; + do { + if (AO_compare_and_swap(&var->counter, (AO_t) exp, (AO_t) new)) + return exp; + act = (long) AO_load(&var->counter); + } while (act == exp); + return act; +} + +static ETHR_INLINE long +ethr_native_atomic_xchg(ethr_native_atomic_t *var, long new) +{ + while (1) { + AO_t exp = AO_load(&var->counter); + if (AO_compare_and_swap(&var->counter, exp, (AO_t) new)) + return (long) exp; + } +} + +/* + * Atomic ops with at least specified barriers. + */ + +static ETHR_INLINE long +ethr_native_atomic_read_acqb(ethr_native_atomic_t *var) +{ +#ifdef AO_HAVE_load_acquire + return (long) AO_load_acquire(&var->counter); +#else + long res = ethr_native_atomic_read(var); + ETHR_MEMORY_BARRIER; + return res; +#endif +} + +static ETHR_INLINE long +ethr_native_atomic_inc_return_acqb(ethr_native_atomic_t *var) +{ +#ifdef AO_HAVE_fetch_and_add1_acquire + return ((long) AO_fetch_and_add1_acquire(&var->counter)) + 1; +#else + long res = ethr_native_atomic_add_return(var, 1); + ETHR_MEMORY_BARRIER; + return res; +#endif +} + +static ETHR_INLINE void +ethr_native_atomic_set_relb(ethr_native_atomic_t *var, long value) +{ +#ifdef AO_HAVE_store_release + AO_store_release(&var->counter, (AO_t) value); +#else + ETHR_MEMORY_BARRIER; + ethr_native_atomic_set(var, value); +#endif +} + +static ETHR_INLINE long +ethr_native_atomic_dec_return_relb(ethr_native_atomic_t *var) +{ +#ifdef AO_HAVE_fetch_and_sub1_release + return ((long) AO_fetch_and_sub1_release(&var->counter)) - 1; +#else + ETHR_MEMORY_BARRIER; + return ethr_native_atomic_dec_return(var); +#endif +} + +static ETHR_INLINE void +ethr_native_atomic_dec_relb(ethr_native_atomic_t *var) +{ + (void) ethr_native_atomic_dec_return_relb(var); +} + +static ETHR_INLINE long +ethr_native_atomic_cmpxchg_acqb(ethr_native_atomic_t *var, long new, long exp) +{ +#ifdef AO_HAVE_compare_and_swap_acquire + long act; + do { + if (AO_compare_and_swap_acquire(&var->counter, (AO_t) exp, (AO_t) new)) + return exp; + act = (long) AO_load(&var->counter); + } while (act == exp); + AO_nop_full(); + return act; +#else + long act = ethr_native_atomic_cmpxchg(var, new, exp); + ETHR_MEMORY_BARRIER; + return act; +#endif +} + +static ETHR_INLINE long +ethr_native_atomic_cmpxchg_relb(ethr_native_atomic_t *var, long new, long exp) +{ +#ifdef AO_HAVE_compare_and_swap_release + long act; + do { + if (AO_compare_and_swap_release(&var->counter, (AO_t) exp, (AO_t) new)) + return exp; + act = (long) AO_load(&var->counter); + } while (act == exp); + return act; +#else + ETHR_MEMORY_BARRIER; + return ethr_native_atomic_cmpxchg(var, new, exp); +#endif +} + + +#endif + +#endif + +#endif |