glibc/sysdeps/x86/cacheinfo.h
Paul Eggert 581c785bf3 Update copyright dates with scripts/update-copyrights
I used these shell commands:

../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")

and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.

I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah.  I don't
know why I run into these diagnostics whereas others evidently do not.

remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
2022-01-01 11:40:24 -08:00

85 lines
3.2 KiB
C

/* x86 cache info.
Copyright (C) 2020-2022 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;
/* A bit-wise OR of string/memory requirements for optimal performance
e.g. X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB. These bits
are used at runtime to tune implementation behavior. */
int __x86_string_control 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;
if (CPU_FEATURES_ARCH_P (cpu_features, Avoid_Short_Distance_REP_MOVSB))
__x86_string_control
|= X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB;
}
#endif