diff options
Diffstat (limited to 'sysdeps/sparc/cpu_relax.c')
| -rw-r--r-- | sysdeps/sparc/cpu_relax.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/sysdeps/sparc/cpu_relax.c b/sysdeps/sparc/cpu_relax.c new file mode 100644 index 0000000000..973dfb5935 --- /dev/null +++ b/sysdeps/sparc/cpu_relax.c @@ -0,0 +1,40 @@ +/* CPU strand yielding for busy loops. Linux/sparc version. + Copyright (C) 2017-2019 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 + <https://www.gnu.org/licenses/>. */ + +#include <sparc-ifunc.h> + +#ifdef __sparc_v9__ +static void +__cpu_relax_generic (void) +{ + asm volatile ("rd %ccr, %g0;" + "rd %ccr, %g0;" + "rd %ccr, %g0"); +} + +static void +__cpu_relax_pause (void) +{ + asm volatile ("wr %g0, 128, %asr27"); +} + +sparc_libc_ifunc (__cpu_relax, + hwcap & HWCAP_SPARC_PAUSE + ? __cpu_relax_pause + : __cpu_relax_generic) +#endif |