| /* Copyright (C) 2007-2018 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, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <errno.h> |
| #include <sched.h> |
| #include <sysdep.h> |
| |
| #ifdef HAVE_GETCPU_VSYSCALL |
| # define HAVE_VSYSCALL |
| #endif |
| #include <sysdep-vdso.h> |
| |
| #if defined __clang__ && defined __powerpc64__ |
| /* On ppc, sched_getcpu's body eventually expands into asm code |
| that does a bctrl, but clang does not recognize the need to save |
| the link register, so calls loop infinitely instead of returning. |
| As workaround, make a dummy function call that forces a link |
| register save. */ |
| volatile int sched_getcpu_dummy_glob; |
| |
| void __attribute__((noinline)) sched_getcpu_dummy () |
| { |
| sched_getcpu_dummy_glob = 45; |
| } |
| #endif |
| |
| int |
| sched_getcpu (void) |
| { |
| #ifdef __NR_getcpu |
| unsigned int cpu; |
| #if defined __clang__ && defined __powerpc64__ |
| sched_getcpu_dummy (); |
| #endif |
| int r = INLINE_VSYSCALL (getcpu, 3, &cpu, NULL, NULL); |
| |
| return r == -1 ? r : cpu; |
| #else |
| __set_errno (ENOSYS); |
| return -1; |
| #endif |
| } |