| 1 | /* Copyright (C) 2020-2024 Free Software Foundation, Inc. |
|---|---|
| 2 | This file is part of the GNU C Library. |
| 3 | |
| 4 | The GNU C Library is free software; you can redistribute it and/or |
| 5 | modify it under the terms of the GNU Lesser General Public |
| 6 | License as published by the Free Software Foundation; either |
| 7 | version 2.1 of the License, or (at your option) any later version. |
| 8 | |
| 9 | The GNU C Library is distributed in the hope that it will be useful, |
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | Lesser General Public License for more details. |
| 13 | |
| 14 | You should have received a copy of the GNU Lesser General Public |
| 15 | License along with the GNU C Library. If not, see |
| 16 | <https://www.gnu.org/licenses/>. */ |
| 17 | |
| 18 | #include <errno.h> |
| 19 | #include <unistd.h> |
| 20 | #include <sys/auxv.h> |
| 21 | #include <stdbool.h> |
| 22 | |
| 23 | static long int linux_sysconf (int name); |
| 24 | |
| 25 | static inline bool |
| 26 | getauxval2_einval (unsigned long int type, unsigned long int *result) |
| 27 | { |
| 28 | if (__getauxval2 (type, result)) |
| 29 | return true; |
| 30 | |
| 31 | __set_errno (EINVAL); |
| 32 | |
| 33 | return false; |
| 34 | } |
| 35 | |
| 36 | static inline long int |
| 37 | sysconf_get_cache_associativity (unsigned long type) |
| 38 | { |
| 39 | unsigned long int result; |
| 40 | |
| 41 | if (getauxval2_einval (type, result: &result)) |
| 42 | return (result & 0xffff0000) >> 16; |
| 43 | |
| 44 | return -1; |
| 45 | } |
| 46 | |
| 47 | static inline long int |
| 48 | sysconf_get_cache_linesize (unsigned long type) |
| 49 | { |
| 50 | unsigned long int result; |
| 51 | |
| 52 | if (getauxval2_einval (type, result: &result)) |
| 53 | return result & 0xffff; |
| 54 | |
| 55 | return -1; |
| 56 | } |
| 57 | |
| 58 | static inline long int |
| 59 | sysconf_get_cache_size (unsigned long type) |
| 60 | { |
| 61 | unsigned long int result; |
| 62 | |
| 63 | if (getauxval2_einval (type, result: &result)) |
| 64 | return result; |
| 65 | |
| 66 | return -1; |
| 67 | } |
| 68 | |
| 69 | /* Get the value of the system variable NAME. */ |
| 70 | long int |
| 71 | __sysconf (int name) |
| 72 | { |
| 73 | switch (name) |
| 74 | { |
| 75 | case _SC_LEVEL1_ICACHE_SIZE: |
| 76 | return sysconf_get_cache_size (AT_L1I_CACHESIZE); |
| 77 | case _SC_LEVEL1_ICACHE_ASSOC: |
| 78 | return sysconf_get_cache_associativity (AT_L1I_CACHEGEOMETRY); |
| 79 | case _SC_LEVEL1_ICACHE_LINESIZE: |
| 80 | return sysconf_get_cache_linesize (AT_L1I_CACHEGEOMETRY); |
| 81 | case _SC_LEVEL1_DCACHE_SIZE: |
| 82 | return sysconf_get_cache_size (AT_L1D_CACHESIZE); |
| 83 | case _SC_LEVEL1_DCACHE_ASSOC: |
| 84 | return sysconf_get_cache_associativity (AT_L1D_CACHEGEOMETRY); |
| 85 | case _SC_LEVEL1_DCACHE_LINESIZE: |
| 86 | return sysconf_get_cache_linesize (AT_L1D_CACHEGEOMETRY); |
| 87 | case _SC_LEVEL2_CACHE_SIZE: |
| 88 | return sysconf_get_cache_size (AT_L2_CACHESIZE); |
| 89 | case _SC_LEVEL2_CACHE_ASSOC: |
| 90 | return sysconf_get_cache_associativity (AT_L2_CACHEGEOMETRY); |
| 91 | case _SC_LEVEL2_CACHE_LINESIZE: |
| 92 | return sysconf_get_cache_linesize (AT_L2_CACHEGEOMETRY); |
| 93 | case _SC_LEVEL3_CACHE_SIZE: |
| 94 | return sysconf_get_cache_size (AT_L3_CACHESIZE); |
| 95 | case _SC_LEVEL3_CACHE_ASSOC: |
| 96 | return sysconf_get_cache_associativity (AT_L3_CACHEGEOMETRY); |
| 97 | case _SC_LEVEL3_CACHE_LINESIZE: |
| 98 | return sysconf_get_cache_linesize (AT_L3_CACHEGEOMETRY); |
| 99 | default: |
| 100 | return linux_sysconf (name); |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | /* Now the generic Linux version. */ |
| 105 | #undef __sysconf |
| 106 | #define __sysconf static linux_sysconf |
| 107 | #include <sysdeps/unix/sysv/linux/sysconf.c> |
| 108 |