1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/netwerk/sctp/src/user_atomic.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,300 @@
1.4 +/*-
1.5 + * Copyright (c) 2009-2010 Brad Penoff
1.6 + * Copyright (c) 2009-2010 Humaira Kamal
1.7 + * Copyright (c) 2011-2012 Irene Ruengeler
1.8 + * Copyright (c) 2011-2012 Michael Tuexen
1.9 + *
1.10 + * All rights reserved.
1.11 + *
1.12 + * Redistribution and use in source and binary forms, with or without
1.13 + * modification, are permitted provided that the following conditions
1.14 + * are met:
1.15 + * 1. Redistributions of source code must retain the above copyright
1.16 + * notice, this list of conditions and the following disclaimer.
1.17 + * 2. Redistributions in binary form must reproduce the above copyright
1.18 + * notice, this list of conditions and the following disclaimer in the
1.19 + * documentation and/or other materials provided with the distribution.
1.20 + *
1.21 + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
1.22 + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1.23 + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
1.24 + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
1.25 + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
1.26 + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
1.27 + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
1.28 + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
1.29 + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
1.30 + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
1.31 + * SUCH DAMAGE.
1.32 + */
1.33 +
1.34 +#ifndef _USER_ATOMIC_H_
1.35 +#define _USER_ATOMIC_H_
1.36 +
1.37 +/* __Userspace__ version of sys/i386/include/atomic.h goes here */
1.38 +
1.39 +/* TODO In the future, might want to not use i386 specific assembly.
1.40 + * The options include:
1.41 + * - implement them generically (but maybe not truly atomic?) in userspace
1.42 + * - have ifdef's for __Userspace_arch_ perhaps (OS isn't enough...)
1.43 + */
1.44 +
1.45 +#include <stdio.h>
1.46 +#include <sys/types.h>
1.47 +
1.48 +#if defined(__Userspace_os_Darwin) || defined (__Userspace_os_Windows)
1.49 +#if defined (__Userspace_os_Windows)
1.50 +#define atomic_add_int(addr, val) InterlockedExchangeAdd((LPLONG)addr, (LONG)val)
1.51 +#define atomic_fetchadd_int(addr, val) InterlockedExchangeAdd((LPLONG)addr, (LONG)val)
1.52 +#define atomic_subtract_int(addr, val) InterlockedExchangeAdd((LPLONG)addr,-((LONG)val))
1.53 +#define atomic_cmpset_int(dst, exp, src) InterlockedCompareExchange((LPLONG)dst, src, exp)
1.54 +#define SCTP_DECREMENT_AND_CHECK_REFCOUNT(addr) (InterlockedExchangeAdd((LPLONG)addr, (-1L)) == 1)
1.55 +#else
1.56 +#include <libkern/OSAtomic.h>
1.57 +#define atomic_add_int(addr, val) OSAtomicAdd32Barrier(val, (int32_t *)addr)
1.58 +#define atomic_fetchadd_int(addr, val) OSAtomicAdd32Barrier(val, (int32_t *)addr)
1.59 +#define atomic_subtract_int(addr, val) OSAtomicAdd32Barrier(-val, (int32_t *)addr)
1.60 +#define atomic_cmpset_int(dst, exp, src) OSAtomicCompareAndSwapIntBarrier(exp, src, (int *)dst)
1.61 +#define SCTP_DECREMENT_AND_CHECK_REFCOUNT(addr) (atomic_fetchadd_int(addr, -1) == 0)
1.62 +#endif
1.63 +
1.64 +#if defined(INVARIANTS)
1.65 +#define SCTP_SAVE_ATOMIC_DECREMENT(addr, val) \
1.66 +{ \
1.67 + int32_t newval; \
1.68 + newval = atomic_fetchadd_int(addr, -val); \
1.69 + if (newval < 0) { \
1.70 + panic("Counter goes negative"); \
1.71 + } \
1.72 +}
1.73 +#else
1.74 +#define SCTP_SAVE_ATOMIC_DECREMENT(addr, val) \
1.75 +{ \
1.76 + int32_t newval; \
1.77 + newval = atomic_fetchadd_int(addr, -val); \
1.78 + if (newval < 0) { \
1.79 + *addr = 0; \
1.80 + } \
1.81 +}
1.82 +#if defined(__Userspace_os_Windows)
1.83 +static void atomic_init() {} /* empty when we are not using atomic_mtx */
1.84 +#else
1.85 +static inline void atomic_init() {} /* empty when we are not using atomic_mtx */
1.86 +#endif
1.87 +#endif
1.88 +
1.89 +#else
1.90 +/* Using gcc built-in functions for atomic memory operations
1.91 + Reference: http://gcc.gnu.org/onlinedocs/gcc-4.1.0/gcc/Atomic-Builtins.html
1.92 + Requires gcc version 4.1.0
1.93 + compile with -march=i486
1.94 + */
1.95 +
1.96 +/*Atomically add V to *P.*/
1.97 +#define atomic_add_int(P, V) (void) __sync_fetch_and_add(P, V)
1.98 +
1.99 +/*Atomically subtrace V from *P.*/
1.100 +#define atomic_subtract_int(P, V) (void) __sync_fetch_and_sub(P, V)
1.101 +
1.102 +/*
1.103 + * Atomically add the value of v to the integer pointed to by p and return
1.104 + * the previous value of *p.
1.105 + */
1.106 +#define atomic_fetchadd_int(p, v) __sync_fetch_and_add(p, v)
1.107 +
1.108 +/* Following explanation from src/sys/i386/include/atomic.h,
1.109 + * for atomic compare and set
1.110 + *
1.111 + * if (*dst == exp) *dst = src (all 32 bit words)
1.112 + *
1.113 + * Returns 0 on failure, non-zero on success
1.114 + */
1.115 +
1.116 +#define atomic_cmpset_int(dst, exp, src) __sync_bool_compare_and_swap(dst, exp, src)
1.117 +
1.118 +#define SCTP_DECREMENT_AND_CHECK_REFCOUNT(addr) (atomic_fetchadd_int(addr, -1) == 1)
1.119 +#if defined(INVARIANTS)
1.120 +#define SCTP_SAVE_ATOMIC_DECREMENT(addr, val) \
1.121 +{ \
1.122 + int32_t oldval; \
1.123 + oldval = atomic_fetchadd_int(addr, -val); \
1.124 + if (oldval < val) { \
1.125 + panic("Counter goes negative"); \
1.126 + } \
1.127 +}
1.128 +#else
1.129 +#define SCTP_SAVE_ATOMIC_DECREMENT(addr, val) \
1.130 +{ \
1.131 + int32_t oldval; \
1.132 + oldval = atomic_fetchadd_int(addr, -val); \
1.133 + if (oldval < val) { \
1.134 + *addr = 0; \
1.135 + } \
1.136 +}
1.137 +#endif
1.138 +static inline void atomic_init() {} /* empty when we are not using atomic_mtx */
1.139 +#endif
1.140 +
1.141 +#if 0 /* using libatomic_ops */
1.142 +#include "user_include/atomic_ops.h"
1.143 +
1.144 +/*Atomically add incr to *P, and return the original value of *P.*/
1.145 +#define atomic_add_int(P, V) AO_fetch_and_add((AO_t*)P, V)
1.146 +
1.147 +#define atomic_subtract_int(P, V) AO_fetch_and_add((AO_t*)P, -(V))
1.148 +
1.149 +/*
1.150 + * Atomically add the value of v to the integer pointed to by p and return
1.151 + * the previous value of *p.
1.152 + */
1.153 +#define atomic_fetchadd_int(p, v) AO_fetch_and_add((AO_t*)p, v)
1.154 +
1.155 +/* Atomically compare *addr to old_val, and replace *addr by new_val
1.156 + if the first comparison succeeds. Returns nonzero if the comparison
1.157 + succeeded and *addr was updated.
1.158 +*/
1.159 +/* Following Explanation from src/sys/i386/include/atomic.h, which
1.160 + matches that of AO_compare_and_swap above.
1.161 + * Atomic compare and set, used by the mutex functions
1.162 + *
1.163 + * if (*dst == exp) *dst = src (all 32 bit words)
1.164 + *
1.165 + * Returns 0 on failure, non-zero on success
1.166 + */
1.167 +
1.168 +#define atomic_cmpset_int(dst, exp, src) AO_compare_and_swap((AO_t*)dst, exp, src)
1.169 +
1.170 +static inline void atomic_init() {} /* empty when we are not using atomic_mtx */
1.171 +#endif /* closing #if for libatomic */
1.172 +
1.173 +#if 0 /* using atomic_mtx */
1.174 +
1.175 +#include <pthread.h>
1.176 +
1.177 +extern userland_mutex_t atomic_mtx;
1.178 +
1.179 +#if defined (__Userspace_os_Windows)
1.180 +static inline void atomic_init() {
1.181 + InitializeCriticalSection(&atomic_mtx);
1.182 +}
1.183 +static inline void atomic_destroy() {
1.184 + DeleteCriticalSection(&atomic_mtx);
1.185 +}
1.186 +static inline void atomic_lock() {
1.187 + EnterCriticalSection(&atomic_mtx);
1.188 +}
1.189 +static inline void atomic_unlock() {
1.190 + LeaveCriticalSection(&atomic_mtx);
1.191 +}
1.192 +#else
1.193 +static inline void atomic_init() {
1.194 + (void)pthread_mutex_init(&atomic_mtx, NULL);
1.195 +}
1.196 +static inline void atomic_destroy() {
1.197 + (void)pthread_mutex_destroy(&atomic_mtx);
1.198 +}
1.199 +static inline void atomic_lock() {
1.200 + (void)pthread_mutex_lock(&atomic_mtx);
1.201 +}
1.202 +static inline void atomic_unlock() {
1.203 + (void)pthread_mutex_unlock(&atomic_mtx);
1.204 +}
1.205 +#endif
1.206 +/*
1.207 + * For userland, always use lock prefixes so that the binaries will run
1.208 + * on both SMP and !SMP systems.
1.209 + */
1.210 +
1.211 +#define MPLOCKED "lock ; "
1.212 +
1.213 +/*
1.214 + * Atomically add the value of v to the integer pointed to by p and return
1.215 + * the previous value of *p.
1.216 + */
1.217 +static __inline u_int
1.218 +atomic_fetchadd_int(volatile void *n, u_int v)
1.219 +{
1.220 + int *p = (int *) n;
1.221 + atomic_lock();
1.222 + __asm __volatile(
1.223 + " " MPLOCKED " "
1.224 + " xaddl %0, %1 ; "
1.225 + "# atomic_fetchadd_int"
1.226 + : "+r" (v), /* 0 (result) */
1.227 + "=m" (*p) /* 1 */
1.228 + : "m" (*p)); /* 2 */
1.229 + atomic_unlock();
1.230 +
1.231 + return (v);
1.232 +}
1.233 +
1.234 +
1.235 +#ifdef CPU_DISABLE_CMPXCHG
1.236 +
1.237 +static __inline int
1.238 +atomic_cmpset_int(volatile u_int *dst, u_int exp, u_int src)
1.239 +{
1.240 + u_char res;
1.241 +
1.242 + atomic_lock();
1.243 + __asm __volatile(
1.244 + " pushfl ; "
1.245 + " cli ; "
1.246 + " cmpl %3,%4 ; "
1.247 + " jne 1f ; "
1.248 + " movl %2,%1 ; "
1.249 + "1: "
1.250 + " sete %0 ; "
1.251 + " popfl ; "
1.252 + "# atomic_cmpset_int"
1.253 + : "=q" (res), /* 0 */
1.254 + "=m" (*dst) /* 1 */
1.255 + : "r" (src), /* 2 */
1.256 + "r" (exp), /* 3 */
1.257 + "m" (*dst) /* 4 */
1.258 + : "memory");
1.259 + atomic_unlock();
1.260 +
1.261 + return (res);
1.262 +}
1.263 +
1.264 +#else /* !CPU_DISABLE_CMPXCHG */
1.265 +
1.266 +static __inline int
1.267 +atomic_cmpset_int(volatile u_int *dst, u_int exp, u_int src)
1.268 +{
1.269 + atomic_lock();
1.270 + u_char res;
1.271 +
1.272 + __asm __volatile(
1.273 + " " MPLOCKED " "
1.274 + " cmpxchgl %2,%1 ; "
1.275 + " sete %0 ; "
1.276 + "1: "
1.277 + "# atomic_cmpset_int"
1.278 + : "=a" (res), /* 0 */
1.279 + "=m" (*dst) /* 1 */
1.280 + : "r" (src), /* 2 */
1.281 + "a" (exp), /* 3 */
1.282 + "m" (*dst) /* 4 */
1.283 + : "memory");
1.284 + atomic_unlock();
1.285 +
1.286 + return (res);
1.287 +}
1.288 +
1.289 +#endif /* CPU_DISABLE_CMPXCHG */
1.290 +
1.291 +#define atomic_add_int(P, V) do { \
1.292 + atomic_lock(); \
1.293 + (*(u_int *)(P) += (V)); \
1.294 + atomic_unlock(); \
1.295 +} while(0)
1.296 +#define atomic_subtract_int(P, V) do { \
1.297 + atomic_lock(); \
1.298 + (*(u_int *)(P) -= (V)); \
1.299 + atomic_unlock(); \
1.300 +} while(0)
1.301 +
1.302 +#endif
1.303 +#endif
