X-Git-Url: https://oss.titaniummirror.com/gitweb?a=blobdiff_plain;f=libgomp%2Fconfig%2Flinux%2Flock.c;fp=libgomp%2Fconfig%2Flinux%2Flock.c;h=405460780a94eb6459205616d63d936715035bc9;hb=6fed43773c9b0ce596dca5686f37ac3fc0fa11c0;hp=0000000000000000000000000000000000000000;hpb=27b11d56b743098deb193d510b337ba22dc52e5c;p=msp430-gcc.git diff --git a/libgomp/config/linux/lock.c b/libgomp/config/linux/lock.c new file mode 100644 index 00000000..40546078 --- /dev/null +++ b/libgomp/config/linux/lock.c @@ -0,0 +1,256 @@ +/* Copyright (C) 2005, 2008, 2009 Free Software Foundation, Inc. + Contributed by Richard Henderson . + + This file is part of the GNU OpenMP Library (libgomp). + + Libgomp is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3, or (at your option) + any later version. + + Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY + WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS + FOR A PARTICULAR PURPOSE. See the GNU General Public License for + more details. + + Under Section 7 of GPL version 3, you are granted additional + permissions described in the GCC Runtime Library Exception, version + 3.1, as published by the Free Software Foundation. + + You should have received a copy of the GNU General Public License and + a copy of the GCC Runtime Library Exception along with this program; + see the files COPYING3 and COPYING.RUNTIME respectively. If not, see + . */ + +/* This is a Linux specific implementation of the public OpenMP locking + primitives. This implementation uses atomic instructions and the futex + syscall. */ + +#include +#include +#include +#include "wait.h" + + +/* The internal gomp_mutex_t and the external non-recursive omp_lock_t + have the same form. Re-use it. */ + +void +gomp_init_lock_30 (omp_lock_t *lock) +{ + gomp_mutex_init (lock); +} + +void +gomp_destroy_lock_30 (omp_lock_t *lock) +{ + gomp_mutex_destroy (lock); +} + +void +gomp_set_lock_30 (omp_lock_t *lock) +{ + gomp_mutex_lock (lock); +} + +void +gomp_unset_lock_30 (omp_lock_t *lock) +{ + gomp_mutex_unlock (lock); +} + +int +gomp_test_lock_30 (omp_lock_t *lock) +{ + return __sync_bool_compare_and_swap (lock, 0, 1); +} + +void +gomp_init_nest_lock_30 (omp_nest_lock_t *lock) +{ + memset (lock, '\0', sizeof (*lock)); +} + +void +gomp_destroy_nest_lock_30 (omp_nest_lock_t *lock) +{ +} + +void +gomp_set_nest_lock_30 (omp_nest_lock_t *lock) +{ + void *me = gomp_icv (true); + + if (lock->owner != me) + { + gomp_mutex_lock (&lock->lock); + lock->owner = me; + } + + lock->count++; +} + +void +gomp_unset_nest_lock_30 (omp_nest_lock_t *lock) +{ + if (--lock->count == 0) + { + lock->owner = NULL; + gomp_mutex_unlock (&lock->lock); + } +} + +int +gomp_test_nest_lock_30 (omp_nest_lock_t *lock) +{ + void *me = gomp_icv (true); + + if (lock->owner == me) + return ++lock->count; + + if (__sync_bool_compare_and_swap (&lock->lock, 0, 1)) + { + lock->owner = me; + lock->count = 1; + return 1; + } + + return 0; +} + +#ifdef LIBGOMP_GNU_SYMBOL_VERSIONING +/* gomp_mutex_* can be safely locked in one thread and + unlocked in another thread, so the OpenMP 2.5 and OpenMP 3.0 + non-nested locks can be the same. */ +strong_alias (gomp_init_lock_30, gomp_init_lock_25) +strong_alias (gomp_destroy_lock_30, gomp_destroy_lock_25) +strong_alias (gomp_set_lock_30, gomp_set_lock_25) +strong_alias (gomp_unset_lock_30, gomp_unset_lock_25) +strong_alias (gomp_test_lock_30, gomp_test_lock_25) + +/* The external recursive omp_nest_lock_25_t form requires additional work. */ + +/* We need an integer to uniquely identify this thread. Most generally + this is the thread's TID, which ideally we'd get this straight from + the TLS block where glibc keeps it. Unfortunately, we can't get at + that directly. + + If we don't support (or have disabled) TLS, one function call is as + good (or bad) as any other. Use the syscall all the time. + + On an ILP32 system (defined here as not LP64), we can make do with + any thread-local pointer. Ideally we'd use the TLS base address, + since that requires the least amount of arithmetic, but that's not + always available directly. Make do with the gomp_thread pointer + since it's handy. */ + +# if !defined (HAVE_TLS) +static inline int gomp_tid (void) +{ + return syscall (SYS_gettid); +} +# elif !defined(__LP64__) +static inline int gomp_tid (void) +{ + return (int) gomp_thread (); +} +# else +static __thread int tid_cache; +static inline int gomp_tid (void) +{ + int tid = tid_cache; + if (__builtin_expect (tid == 0, 0)) + tid_cache = tid = syscall (SYS_gettid); + return tid; +} +# endif + + +void +gomp_init_nest_lock_25 (omp_nest_lock_25_t *lock) +{ + memset (lock, 0, sizeof (lock)); +} + +void +gomp_destroy_nest_lock_25 (omp_nest_lock_25_t *lock) +{ +} + +void +gomp_set_nest_lock_25 (omp_nest_lock_25_t *lock) +{ + int otid, tid = gomp_tid (); + + while (1) + { + otid = __sync_val_compare_and_swap (&lock->owner, 0, tid); + if (otid == 0) + { + lock->count = 1; + return; + } + if (otid == tid) + { + lock->count++; + return; + } + + do_wait (&lock->owner, otid); + } +} + +void +gomp_unset_nest_lock_25 (omp_nest_lock_25_t *lock) +{ + /* ??? Validate that we own the lock here. */ + + if (--lock->count == 0) + { + __sync_lock_release (&lock->owner); + futex_wake (&lock->owner, 1); + } +} + +int +gomp_test_nest_lock_25 (omp_nest_lock_25_t *lock) +{ + int otid, tid = gomp_tid (); + + otid = __sync_val_compare_and_swap (&lock->owner, 0, tid); + if (otid == 0) + { + lock->count = 1; + return 1; + } + if (otid == tid) + return ++lock->count; + + return 0; +} + +omp_lock_symver (omp_init_lock) +omp_lock_symver (omp_destroy_lock) +omp_lock_symver (omp_set_lock) +omp_lock_symver (omp_unset_lock) +omp_lock_symver (omp_test_lock) +omp_lock_symver (omp_init_nest_lock) +omp_lock_symver (omp_destroy_nest_lock) +omp_lock_symver (omp_set_nest_lock) +omp_lock_symver (omp_unset_nest_lock) +omp_lock_symver (omp_test_nest_lock) + +#else + +ialias (omp_init_lock) +ialias (omp_init_nest_lock) +ialias (omp_destroy_lock) +ialias (omp_destroy_nest_lock) +ialias (omp_set_lock) +ialias (omp_set_nest_lock) +ialias (omp_unset_lock) +ialias (omp_unset_nest_lock) +ialias (omp_test_lock) +ialias (omp_test_nest_lock) + +#endif