| /* |
| Copyright 2005-2010 Intel Corporation. All Rights Reserved. |
| |
| This file is part of Threading Building Blocks. |
| |
| Threading Building Blocks is free software; you can redistribute it |
| and/or modify it under the terms of the GNU General Public License |
| version 2 as published by the Free Software Foundation. |
| |
| Threading Building Blocks 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. |
| |
| You should have received a copy of the GNU General Public License |
| along with Threading Building Blocks; if not, write to the Free Software |
| Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| |
| As a special exception, you may use this file as part of a free software |
| library without restriction. Specifically, if other files instantiate |
| templates or use macros or inline functions from this file, or you compile |
| this file and link it with other files to produce an executable, this |
| file does not by itself cause the resulting executable to be covered by |
| the GNU General Public License. This exception does not however |
| invalidate any other reasons why the executable file might be covered by |
| the GNU General Public License. |
| */ |
| |
| #ifndef __TBB_machine_H |
| #error Do not include this file directly; include tbb_machine.h instead |
| #endif |
| |
| #include <stdint.h> |
| #include <unistd.h> |
| #include <sched.h> |
| |
| // Definition of __TBB_Yield() |
| #ifndef __TBB_Yield |
| #define __TBB_Yield() sched_yield() |
| #endif |
| |
| /* Futex definitions */ |
| #include <sys/syscall.h> |
| |
| #if defined(SYS_futex) |
| |
| #define __TBB_USE_FUTEX 1 |
| #include <limits.h> |
| #include <errno.h> |
| // Unfortunately, some versions of Linux do not have a header that defines FUTEX_WAIT and FUTEX_WAKE. |
| |
| #ifdef FUTEX_WAIT |
| #define __TBB_FUTEX_WAIT FUTEX_WAIT |
| #else |
| #define __TBB_FUTEX_WAIT 0 |
| #endif |
| |
| #ifdef FUTEX_WAKE |
| #define __TBB_FUTEX_WAKE FUTEX_WAKE |
| #else |
| #define __TBB_FUTEX_WAKE 1 |
| #endif |
| |
| #ifndef __TBB_ASSERT |
| #error machine specific headers must be included after tbb_stddef.h |
| #endif |
| |
| namespace tbb { |
| |
| namespace internal { |
| |
| inline int futex_wait( void *futex, int comparand ) { |
| int r = ::syscall( SYS_futex,futex,__TBB_FUTEX_WAIT,comparand,NULL,NULL,0 ); |
| #if TBB_USE_ASSERT |
| int e = errno; |
| __TBB_ASSERT( r==0||r==EWOULDBLOCK||(r==-1&&(e==EAGAIN||e==EINTR)), "futex_wait failed." ); |
| #endif /* TBB_USE_ASSERT */ |
| return r; |
| } |
| |
| inline int futex_wakeup_one( void *futex ) { |
| int r = ::syscall( SYS_futex,futex,__TBB_FUTEX_WAKE,1,NULL,NULL,0 ); |
| __TBB_ASSERT( r==0||r==1, "futex_wakeup_one: more than one thread woken up?" ); |
| return r; |
| } |
| |
| inline int futex_wakeup_all( void *futex ) { |
| int r = ::syscall( SYS_futex,futex,__TBB_FUTEX_WAKE,INT_MAX,NULL,NULL,0 ); |
| __TBB_ASSERT( r>=0, "futex_wakeup_all: error in waking up threads" ); |
| return r; |
| } |
| |
| } /* namespace internal */ |
| |
| } /* namespace tbb */ |
| |
| #endif /* SYS_futex */ |
