| /* Determine realtime clock frequency. |
| Copyright (C) 2003, 2004, 2006 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library 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 |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #include <sys/time.h> |
| #include <libc-internal.h> |
| #include <kernel-features.h> |
| #include <ldsodefs.h> |
| |
| |
| int |
| __profile_frequency (void) |
| { |
| #ifdef __ASSUME_AT_CLKTCK |
| return GLRO(dl_clktck); |
| #else |
| if (GLRO(dl_clktck) != 0) |
| return GLRO(dl_clktck); |
| |
| struct itimerval tim; |
| |
| tim.it_interval.tv_sec = 0; |
| tim.it_interval.tv_usec = 1; |
| tim.it_value.tv_sec = 0; |
| tim.it_value.tv_usec = 0; |
| |
| __setitimer (ITIMER_REAL, &tim, 0); |
| __setitimer (ITIMER_REAL, 0, &tim); |
| |
| if (tim.it_interval.tv_usec < 2) |
| return 0; |
| |
| return 1000000 / tim.it_interval.tv_usec; |
| #endif |
| } |
| libc_hidden_def (__profile_frequency) |
