mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-26 04:31:03 +00:00
76 lines
2.8 KiB
C
76 lines
2.8 KiB
C
/* x86 cache info.
|
|
Copyright (C) 2020-2021 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 <assert.h>
|
|
#include <unistd.h>
|
|
#include <cpuid.h>
|
|
#include <cpu-features.h>
|
|
|
|
#if HAVE_TUNABLES
|
|
# define TUNABLE_NAMESPACE cpu
|
|
# include <unistd.h> /* Get STDOUT_FILENO for _dl_printf. */
|
|
# include <elf/dl-tunables.h>
|
|
#endif
|
|
|
|
#if IS_IN (libc)
|
|
/* Data cache size for use in memory and string routines, typically
|
|
L1 size, rounded to multiple of 256 bytes. */
|
|
long int __x86_data_cache_size_half attribute_hidden = 32 * 1024 / 2;
|
|
long int __x86_data_cache_size attribute_hidden = 32 * 1024;
|
|
/* Shared cache size for use in memory and string routines, typically
|
|
L2 or L3 size, rounded to multiple of 256 bytes. */
|
|
long int __x86_shared_cache_size_half attribute_hidden = 1024 * 1024 / 2;
|
|
long int __x86_shared_cache_size attribute_hidden = 1024 * 1024;
|
|
|
|
/* Threshold to use non temporal store. */
|
|
long int __x86_shared_non_temporal_threshold attribute_hidden;
|
|
|
|
/* Threshold to use Enhanced REP MOVSB. */
|
|
long int __x86_rep_movsb_threshold attribute_hidden = 2048;
|
|
|
|
/* Threshold to use Enhanced REP STOSB. */
|
|
long int __x86_rep_stosb_threshold attribute_hidden = 2048;
|
|
|
|
/* Threshold to stop using Enhanced REP MOVSB. */
|
|
long int __x86_rep_movsb_stop_threshold attribute_hidden;
|
|
|
|
static void
|
|
init_cacheinfo (void)
|
|
{
|
|
const struct cpu_features *cpu_features = __get_cpu_features ();
|
|
long int data = cpu_features->data_cache_size;
|
|
/* Round data cache size to multiple of 256 bytes. */
|
|
data = data & ~255L;
|
|
__x86_data_cache_size_half = data / 2;
|
|
__x86_data_cache_size = data;
|
|
|
|
long int shared = cpu_features->shared_cache_size;
|
|
/* Round shared cache size to multiple of 256 bytes. */
|
|
shared = shared & ~255L;
|
|
__x86_shared_cache_size_half = shared / 2;
|
|
__x86_shared_cache_size = shared;
|
|
|
|
__x86_shared_non_temporal_threshold
|
|
= cpu_features->non_temporal_threshold;
|
|
|
|
__x86_rep_movsb_threshold = cpu_features->rep_movsb_threshold;
|
|
__x86_rep_stosb_threshold = cpu_features->rep_stosb_threshold;
|
|
__x86_rep_movsb_stop_threshold = cpu_features->rep_movsb_stop_threshold;
|
|
}
|
|
#endif
|