From 23381d2c5ea84cb45e41163b81c3b7bb43a9db75 Mon Sep 17 00:00:00 2001 From: Corey Farrell Date: Thu, 25 Jan 2018 02:37:32 -0500 Subject: Build System: Require __sync or __atomic functions. This change causes the configure script to throw an error if neither __sync nor __atomic builtin functions are available. ASTERISK-27619 Change-Id: Ie01a281e0f5c41dfeeb5f250c1ccea8752f56ef9 --- include/asterisk/autoconfig.h.in | 3 -- include/asterisk/lock.h | 102 +++++++-------------------------------- 2 files changed, 17 insertions(+), 88 deletions(-) (limited to 'include/asterisk') diff --git a/include/asterisk/autoconfig.h.in b/include/asterisk/autoconfig.h.in index 18f9d4e75..b95d52693 100644 --- a/include/asterisk/autoconfig.h.in +++ b/include/asterisk/autoconfig.h.in @@ -603,9 +603,6 @@ /* Define to 1 if you have the Open Sound System library. */ #undef HAVE_OSS -/* Define to 1 if OSX atomic operations are supported. */ -#undef HAVE_OSX_ATOMICS - /* Define to 1 if your system defines the file flag O_EVTONLY in fcntl.h */ #undef HAVE_O_EVTONLY diff --git a/include/asterisk/lock.h b/include/asterisk/lock.h index d912b56d3..c3dd691a8 100644 --- a/include/asterisk/lock.h +++ b/include/asterisk/lock.h @@ -617,107 +617,39 @@ static void __attribute__((destructor)) fini_##rwlock(void) \ #define pthread_create __use_ast_pthread_create_instead__ #endif -/* - * Support for atomic instructions. - * For platforms that have it, use the native cpu instruction to - * implement them. For other platforms, resort to a 'slow' version - * (defined in utils.c) that protects the atomic instruction with - * a single lock. - * The slow versions is always available, for testing purposes, - * as ast_atomic_fetchadd_int_slow() - */ - -int ast_atomic_fetchadd_int_slow(volatile int *p, int v); +/* Support for atomic instructions. */ #include "asterisk/inline_api.h" -#if defined(HAVE_OSX_ATOMICS) -#include "libkern/OSAtomic.h" +#if defined(HAVE_C_ATOMICS) +#define ast_atomic_fetch_add(p, v, memorder) __atomic_fetch_add(p, v, memorder) +#define ast_atomic_sub_fetch(p, v, memorder) __atomic_sub_fetch(p, v, memorder) +#elif defined(HAVE_GCC_ATOMICS) +#define ast_atomic_fetch_add(p, v, memorder) __sync_fetch_and_add(p, v) +#define ast_atomic_sub_fetch(p, v, memorder) __sync_sub_and_fetch(p, v) +#else +#error "Atomics not available." #endif -/*! \brief Atomically add v to *p and return * the previous value of *p. +/*! + * \brief Atomically add v to *p and return the previous value of *p. + * * This can be used to handle reference counts, and the return value * can be used to generate unique identifiers. */ - -#if defined(HAVE_C_ATOMICS) AST_INLINE_API(int ast_atomic_fetchadd_int(volatile int *p, int v), { - return __atomic_fetch_add(p, v, __ATOMIC_RELAXED); + return ast_atomic_fetch_add(p, v, __ATOMIC_RELAXED); }) -#elif defined(HAVE_GCC_ATOMICS) -AST_INLINE_API(int ast_atomic_fetchadd_int(volatile int *p, int v), -{ - return __sync_fetch_and_add(p, v); -}) -#elif defined(HAVE_OSX_ATOMICS) && (SIZEOF_INT == 4) -AST_INLINE_API(int ast_atomic_fetchadd_int(volatile int *p, int v), -{ - return OSAtomicAdd32(v, (int32_t *) p) - v; -}) -#elif defined(HAVE_OSX_ATOMICS) && (SIZEOF_INT == 8) -AST_INLINE_API(int ast_atomic_fetchadd_int(volatile int *p, int v), -{ - return OSAtomicAdd64(v, (int64_t *) p) - v; -}) -#elif defined (__i386__) || defined(__x86_64__) -#ifdef sun -AST_INLINE_API(int ast_atomic_fetchadd_int(volatile int *p, int v), -{ - __asm __volatile ( - " lock; xaddl %0, %1 ; " - : "+r" (v), /* 0 (result) */ - "=m" (*p) /* 1 */ - : "m" (*p)); /* 2 */ - return (v); -}) -#else /* ifndef sun */ -AST_INLINE_API(int ast_atomic_fetchadd_int(volatile int *p, int v), -{ - __asm __volatile ( - " lock xaddl %0, %1 ; " - : "+r" (v), /* 0 (result) */ - "=m" (*p) /* 1 */ - : "m" (*p)); /* 2 */ - return (v); -}) -#endif -#else /* low performance version in utils.c */ -AST_INLINE_API(int ast_atomic_fetchadd_int(volatile int *p, int v), -{ - return ast_atomic_fetchadd_int_slow(p, v); -}) -#endif -/*! \brief decrement *p by 1 and return true if the variable has reached 0. +/*! + * \brief decrement *p by 1 and return true if the variable has reached 0. + * * Useful e.g. to check if a refcount has reached 0. */ -#if defined(HAVE_C_ATOMICS) -AST_INLINE_API(int ast_atomic_dec_and_test(volatile int *p), -{ - return __atomic_sub_fetch(p, 1, __ATOMIC_RELAXED) == 0; -}) -#elif defined(HAVE_GCC_ATOMICS) -AST_INLINE_API(int ast_atomic_dec_and_test(volatile int *p), -{ - return __sync_sub_and_fetch(p, 1) == 0; -}) -#elif defined(HAVE_OSX_ATOMICS) && (SIZEOF_INT == 4) -AST_INLINE_API(int ast_atomic_dec_and_test(volatile int *p), -{ - return OSAtomicAdd32( -1, (int32_t *) p) == 0; -}) -#elif defined(HAVE_OSX_ATOMICS) && (SIZEOF_INT == 8) -AST_INLINE_API(int ast_atomic_dec_and_test(volatile int *p), -{ - return OSAtomicAdd64( -1, (int64_t *) p) == 0; -}) -#else AST_INLINE_API(int ast_atomic_dec_and_test(volatile int *p), { - int a = ast_atomic_fetchadd_int(p, -1); - return a == 1; /* true if the value is 0 now (so it was 1 previously) */ + return ast_atomic_sub_fetch(p, 1, __ATOMIC_RELAXED) == 0; }) -#endif #endif /* _ASTERISK_LOCK_H */ -- cgit v1.2.3