glibc/sysdeps/x86/tst-hwcap-tunables.c
Adhemerval Zanella 2a969b53c0 elf: Do not duplicate the GLIBC_TUNABLES string
The tunable parsing duplicates the tunable environment variable so it
null-terminates each one since it simplifies the later parsing. It has
the drawback of adding another point of failure (__minimal_malloc
failing), and the memory copy requires tuning the compiler to avoid mem
operations calls.

The parsing now tracks the tunable start and its size. The
dl-tunable-parse.h adds helper functions to help parsing, like a strcmp
that also checks for size and an iterator for suboptions that are
comma-separated (used on hwcap parsing by x86, powerpc, and s390x).

Since the environment variable is allocated on the stack by the kernel,
it is safe to keep the references to the suboptions for later parsing
of string tunables (as done by set_hwcaps by multiple architectures).

Checked on x86_64-linux-gnu, powerpc64le-linux-gnu, and
aarch64-linux-gnu.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-12-19 13:25:45 -03:00

149 lines
4.1 KiB
C

/* Tests for x86 GLIBC_TUNABLES=glibc.cpu.hwcaps filter.
Copyright (C) 2023 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
<http://www.gnu.org/licenses/>. */
#include <array_length.h>
#include <getopt.h>
#include <ifunc-impl-list.h>
#include <spawn.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <intprops.h>
#include <support/check.h>
#include <support/support.h>
#include <support/xunistd.h>
#include <support/capture_subprocess.h>
/* Nonzero if the program gets called via `exec'. */
#define CMDLINE_OPTIONS \
{ "restart", no_argument, &restart, 1 },
static int restart;
/* Disable everything. */
static const char *test_1[] =
{
"__memcpy_avx512_no_vzeroupper",
"__memcpy_avx512_unaligned",
"__memcpy_avx512_unaligned_erms",
"__memcpy_evex_unaligned",
"__memcpy_evex_unaligned_erms",
"__memcpy_avx_unaligned",
"__memcpy_avx_unaligned_erms",
"__memcpy_avx_unaligned_rtm",
"__memcpy_avx_unaligned_erms_rtm",
"__memcpy_ssse3",
};
static const struct test_t
{
const char *env;
const char *const *funcs;
size_t nfuncs;
} tests[] =
{
{
/* Disable everything. */
"-Prefer_ERMS,-Prefer_FSRM,-AVX,-AVX2,-AVX_Usable,-AVX2_Usable,"
"-AVX512F_Usable,-SSE4_1,-SSE4_2,-SSSE3,-Fast_Unaligned_Load,-ERMS,"
"-AVX_Fast_Unaligned_Load",
test_1,
array_length (test_1)
},
{
/* Same as before, but with some empty suboptions. */
",-,-Prefer_ERMS,-Prefer_FSRM,-AVX,-AVX2,-AVX_Usable,-AVX2_Usable,"
"-AVX512F_Usable,-SSE4_1,-SSE4_2,,-SSSE3,-Fast_Unaligned_Load,,-,-ERMS,"
"-AVX_Fast_Unaligned_Load,-,",
test_1,
array_length (test_1)
}
};
/* Called on process re-execution. */
_Noreturn static void
handle_restart (int ntest)
{
struct libc_ifunc_impl impls[32];
int cnt = __libc_ifunc_impl_list ("memcpy", impls, array_length (impls));
if (cnt == 0)
_exit (EXIT_SUCCESS);
TEST_VERIFY_EXIT (cnt >= 1);
for (int i = 0; i < cnt; i++)
{
for (int f = 0; f < tests[ntest].nfuncs; f++)
{
if (strcmp (impls[i].name, tests[ntest].funcs[f]) == 0)
TEST_COMPARE (impls[i].usable, false);
}
}
_exit (EXIT_SUCCESS);
}
static int
do_test (int argc, char *argv[])
{
/* We must have either:
- One our fource parameters left if called initially:
+ path to ld.so optional
+ "--library-path" optional
+ the library path optional
+ the application name
+ the test to check */
TEST_VERIFY_EXIT (argc == 2 || argc == 5);
if (restart)
handle_restart (atoi (argv[1]));
char nteststr[INT_BUFSIZE_BOUND (int)];
char *spargv[10];
{
int i = 0;
for (; i < argc - 1; i++)
spargv[i] = argv[i + 1];
spargv[i++] = (char *) "--direct";
spargv[i++] = (char *) "--restart";
spargv[i++] = nteststr;
spargv[i] = NULL;
}
for (int i = 0; i < array_length (tests); i++)
{
snprintf (nteststr, sizeof nteststr, "%d", i);
printf ("[%d] Spawned test for %s\n", i, tests[i].env);
char *tunable = xasprintf ("glibc.cpu.hwcaps=%s", tests[i].env);
setenv ("GLIBC_TUNABLES", tunable, 1);
struct support_capture_subprocess result
= support_capture_subprogram (spargv[0], spargv);
support_capture_subprocess_check (&result, "tst-tunables", 0,
sc_allow_stderr);
support_capture_subprocess_free (&result);
free (tunable);
}
return 0;
}
#define TEST_FUNCTION_ARGV do_test
#include <support/test-driver.c>