| 1 | /* CPU strand yielding for busy loops. Linux/sparc version. |
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| 2 | Copyright (C) 2017-2024 Free Software Foundation, Inc. |
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| 3 | This file is part of the GNU C Library. |
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| 4 | |
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| 5 | The GNU C Library is free software; you can redistribute it and/or |
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| 6 | modify it under the terms of the GNU Lesser General Public |
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| 7 | License as published by the Free Software Foundation; either |
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| 8 | version 2.1 of the License, or (at your option) any later version. |
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| 9 | |
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| 10 | The GNU C Library is distributed in the hope that it will be useful, |
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| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 13 | Lesser General Public License for more details. |
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| 14 | |
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| 15 | You should have received a copy of the GNU Lesser General Public |
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| 16 | License along with the GNU C Library; if not, see |
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| 17 | <https://www.gnu.org/licenses/>. */ |
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| 18 | |
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| 19 | #include <sparc-ifunc.h> |
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| 20 | |
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| 21 | #ifdef __sparc_v9__ |
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| 22 | static void |
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| 23 | __cpu_relax_generic (void) |
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| 24 | { |
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| 25 | asm volatile ("rd %ccr, %g0;" |
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| 26 | "rd %ccr, %g0;" |
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| 27 | "rd %ccr, %g0" ); |
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| 28 | } |
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| 29 | |
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| 30 | static void |
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| 31 | __cpu_relax_pause (void) |
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| 32 | { |
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| 33 | asm volatile ("wr %g0, 128, %asr27" ); |
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| 34 | } |
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| 35 | |
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| 36 | sparc_libc_ifunc (__cpu_relax, |
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| 37 | hwcap & HWCAP_SPARC_PAUSE |
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| 38 | ? __cpu_relax_pause |
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| 39 | : __cpu_relax_generic) |
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| 40 | #endif |
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| 41 | |
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