kernel/tools/testing/selftests/arm64/fp/vec-syscfg.c
2024-07-22 17:22:30 +08:00

594 lines
14 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2021 ARM Limited.
* Original author: Mark Brown <broonie@kernel.org>
*/
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/auxv.h>
#include <sys/prctl.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <asm/sigcontext.h>
#include <asm/hwcap.h>
#include "../../kselftest.h"
#include "rdvl.h"
#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0]))
#define ARCH_MIN_VL SVE_VL_MIN
struct vec_data {
const char *name;
unsigned long hwcap_type;
unsigned long hwcap;
const char *rdvl_binary;
int (*rdvl)(void);
int prctl_get;
int prctl_set;
const char *default_vl_file;
int default_vl;
int min_vl;
int max_vl;
};
static struct vec_data vec_data[] = {
{
.name = "SVE",
.hwcap_type = AT_HWCAP,
.hwcap = HWCAP_SVE,
.rdvl = rdvl_sve,
.rdvl_binary = "./rdvl-sve",
.prctl_get = PR_SVE_GET_VL,
.prctl_set = PR_SVE_SET_VL,
.default_vl_file = "/proc/sys/abi/sve_default_vector_length",
},
};
static int stdio_read_integer(FILE *f, const char *what, int *val)
{
int n = 0;
int ret;
ret = fscanf(f, "%d%*1[\n]%n", val, &n);
if (ret < 1 || n < 1) {
ksft_print_msg("failed to parse integer from %s\n", what);
return -1;
}
return 0;
}
/* Start a new process and return the vector length it sees */
static int get_child_rdvl(struct vec_data *data)
{
FILE *out;
int pipefd[2];
pid_t pid, child;
int read_vl, ret;
ret = pipe(pipefd);
if (ret == -1) {
ksft_print_msg("pipe() failed: %d (%s)\n",
errno, strerror(errno));
return -1;
}
fflush(stdout);
child = fork();
if (child == -1) {
ksft_print_msg("fork() failed: %d (%s)\n",
errno, strerror(errno));
close(pipefd[0]);
close(pipefd[1]);
return -1;
}
/* Child: put vector length on the pipe */
if (child == 0) {
/*
* Replace stdout with the pipe, errors to stderr from
* here as kselftest prints to stdout.
*/
ret = dup2(pipefd[1], 1);
if (ret == -1) {
fprintf(stderr, "dup2() %d\n", errno);
exit(EXIT_FAILURE);
}
/* exec() a new binary which puts the VL on stdout */
ret = execl(data->rdvl_binary, data->rdvl_binary, NULL);
fprintf(stderr, "execl(%s) failed: %d\n",
data->rdvl_binary, errno, strerror(errno));
exit(EXIT_FAILURE);
}
close(pipefd[1]);
/* Parent; wait for the exit status from the child & verify it */
do {
pid = wait(&ret);
if (pid == -1) {
ksft_print_msg("wait() failed: %d (%s)\n",
errno, strerror(errno));
close(pipefd[0]);
return -1;
}
} while (pid != child);
assert(pid == child);
if (!WIFEXITED(ret)) {
ksft_print_msg("child exited abnormally\n");
close(pipefd[0]);
return -1;
}
if (WEXITSTATUS(ret) != 0) {
ksft_print_msg("child returned error %d\n",
WEXITSTATUS(ret));
close(pipefd[0]);
return -1;
}
out = fdopen(pipefd[0], "r");
if (!out) {
ksft_print_msg("failed to open child stdout\n");
close(pipefd[0]);
return -1;
}
ret = stdio_read_integer(out, "child", &read_vl);
fclose(out);
if (ret != 0)
return ret;
return read_vl;
}
static int file_read_integer(const char *name, int *val)
{
FILE *f;
int ret;
f = fopen(name, "r");
if (!f) {
ksft_test_result_fail("Unable to open %s: %d (%s)\n",
name, errno,
strerror(errno));
return -1;
}
ret = stdio_read_integer(f, name, val);
fclose(f);
return ret;
}
static int file_write_integer(const char *name, int val)
{
FILE *f;
int ret;
f = fopen(name, "w");
if (!f) {
ksft_test_result_fail("Unable to open %s: %d (%s)\n",
name, errno,
strerror(errno));
return -1;
}
fprintf(f, "%d", val);
fclose(f);
if (ret < 0) {
ksft_test_result_fail("Error writing %d to %s\n",
val, name);
return -1;
}
return 0;
}
/*
* Verify that we can read the default VL via proc, checking that it
* is set in a freshly spawned child.
*/
static void proc_read_default(struct vec_data *data)
{
int default_vl, child_vl, ret;
ret = file_read_integer(data->default_vl_file, &default_vl);
if (ret != 0)
return;
/* Is this the actual default seen by new processes? */
child_vl = get_child_rdvl(data);
if (child_vl != default_vl) {
ksft_test_result_fail("%s is %d but child VL is %d\n",
data->default_vl_file,
default_vl, child_vl);
return;
}
ksft_test_result_pass("%s default vector length %d\n", data->name,
default_vl);
data->default_vl = default_vl;
}
/* Verify that we can write a minimum value and have it take effect */
static void proc_write_min(struct vec_data *data)
{
int ret, new_default, child_vl;
if (geteuid() != 0) {
ksft_test_result_skip("Need to be root to write to /proc\n");
return;
}
ret = file_write_integer(data->default_vl_file, ARCH_MIN_VL);
if (ret != 0)
return;
/* What was the new value? */
ret = file_read_integer(data->default_vl_file, &new_default);
if (ret != 0)
return;
/* Did it take effect in a new process? */
child_vl = get_child_rdvl(data);
if (child_vl != new_default) {
ksft_test_result_fail("%s is %d but child VL is %d\n",
data->default_vl_file,
new_default, child_vl);
return;
}
ksft_test_result_pass("%s minimum vector length %d\n", data->name,
new_default);
data->min_vl = new_default;
file_write_integer(data->default_vl_file, data->default_vl);
}
/* Verify that we can write a maximum value and have it take effect */
static void proc_write_max(struct vec_data *data)
{
int ret, new_default, child_vl;
if (geteuid() != 0) {
ksft_test_result_skip("Need to be root to write to /proc\n");
return;
}
/* -1 is accepted by the /proc interface as the maximum VL */
ret = file_write_integer(data->default_vl_file, -1);
if (ret != 0)
return;
/* What was the new value? */
ret = file_read_integer(data->default_vl_file, &new_default);
if (ret != 0)
return;
/* Did it take effect in a new process? */
child_vl = get_child_rdvl(data);
if (child_vl != new_default) {
ksft_test_result_fail("%s is %d but child VL is %d\n",
data->default_vl_file,
new_default, child_vl);
return;
}
ksft_test_result_pass("%s maximum vector length %d\n", data->name,
new_default);
data->max_vl = new_default;
file_write_integer(data->default_vl_file, data->default_vl);
}
/* Can we read back a VL from prctl? */
static void prctl_get(struct vec_data *data)
{
int ret;
ret = prctl(data->prctl_get);
if (ret == -1) {
ksft_test_result_fail("%s prctl() read failed: %d (%s)\n",
data->name, errno, strerror(errno));
return;
}
/* Mask out any flags */
ret &= PR_SVE_VL_LEN_MASK;
/* Is that what we can read back directly? */
if (ret == data->rdvl())
ksft_test_result_pass("%s current VL is %d\n",
data->name, ret);
else
ksft_test_result_fail("%s prctl() VL %d but RDVL is %d\n",
data->name, ret, data->rdvl());
}
/* Does the prctl let us set the VL we already have? */
static void prctl_set_same(struct vec_data *data)
{
int cur_vl = data->rdvl();
int ret;
ret = prctl(data->prctl_set, cur_vl);
if (ret < 0) {
ksft_test_result_fail("%s prctl set failed: %d (%s)\n",
data->name, errno, strerror(errno));
return;
}
if (cur_vl != data->rdvl())
ksft_test_result_pass("%s current VL is %d\n",
data->name, ret);
else
ksft_test_result_fail("%s prctl() VL %d but RDVL is %d\n",
data->name, ret, data->rdvl());
}
/* Can we set a new VL for this process? */
static void prctl_set(struct vec_data *data)
{
int ret;
if (data->min_vl == data->max_vl) {
ksft_test_result_skip("%s only one VL supported\n",
data->name);
return;
}
/* Try to set the minimum VL */
ret = prctl(data->prctl_set, data->min_vl);
if (ret < 0) {
ksft_test_result_fail("%s prctl set failed for %d: %d (%s)\n",
data->name, data->min_vl,
errno, strerror(errno));
return;
}
if ((ret & PR_SVE_VL_LEN_MASK) != data->min_vl) {
ksft_test_result_fail("%s prctl set %d but return value is %d\n",
data->name, data->min_vl, data->rdvl());
return;
}
if (data->rdvl() != data->min_vl) {
ksft_test_result_fail("%s set %d but RDVL is %d\n",
data->name, data->min_vl, data->rdvl());
return;
}
/* Try to set the maximum VL */
ret = prctl(data->prctl_set, data->max_vl);
if (ret < 0) {
ksft_test_result_fail("%s prctl set failed for %d: %d (%s)\n",
data->name, data->max_vl,
errno, strerror(errno));
return;
}
if ((ret & PR_SVE_VL_LEN_MASK) != data->max_vl) {
ksft_test_result_fail("%s prctl() set %d but return value is %d\n",
data->name, data->max_vl, data->rdvl());
return;
}
/* The _INHERIT flag should not be present when we read the VL */
ret = prctl(data->prctl_get);
if (ret == -1) {
ksft_test_result_fail("%s prctl() read failed: %d (%s)\n",
data->name, errno, strerror(errno));
return;
}
if (ret & PR_SVE_VL_INHERIT) {
ksft_test_result_fail("%s prctl() reports _INHERIT\n",
data->name);
return;
}
ksft_test_result_pass("%s prctl() set min/max\n", data->name);
}
/* If we didn't request it a new VL shouldn't affect the child */
static void prctl_set_no_child(struct vec_data *data)
{
int ret, child_vl;
if (data->min_vl == data->max_vl) {
ksft_test_result_skip("%s only one VL supported\n",
data->name);
return;
}
ret = prctl(data->prctl_set, data->min_vl);
if (ret < 0) {
ksft_test_result_fail("%s prctl set failed for %d: %d (%s)\n",
data->name, data->min_vl,
errno, strerror(errno));
return;
}
/* Ensure the default VL is different */
ret = file_write_integer(data->default_vl_file, data->max_vl);
if (ret != 0)
return;
/* Check that the child has the default we just set */
child_vl = get_child_rdvl(data);
if (child_vl != data->max_vl) {
ksft_test_result_fail("%s is %d but child VL is %d\n",
data->default_vl_file,
data->max_vl, child_vl);
return;
}
ksft_test_result_pass("%s vector length used default\n", data->name);
file_write_integer(data->default_vl_file, data->default_vl);
}
/* If we didn't request it a new VL shouldn't affect the child */
static void prctl_set_for_child(struct vec_data *data)
{
int ret, child_vl;
if (data->min_vl == data->max_vl) {
ksft_test_result_skip("%s only one VL supported\n",
data->name);
return;
}
ret = prctl(data->prctl_set, data->min_vl | PR_SVE_VL_INHERIT);
if (ret < 0) {
ksft_test_result_fail("%s prctl set failed for %d: %d (%s)\n",
data->name, data->min_vl,
errno, strerror(errno));
return;
}
/* The _INHERIT flag should be present when we read the VL */
ret = prctl(data->prctl_get);
if (ret == -1) {
ksft_test_result_fail("%s prctl() read failed: %d (%s)\n",
data->name, errno, strerror(errno));
return;
}
if (!(ret & PR_SVE_VL_INHERIT)) {
ksft_test_result_fail("%s prctl() does not report _INHERIT\n",
data->name);
return;
}
/* Ensure the default VL is different */
ret = file_write_integer(data->default_vl_file, data->max_vl);
if (ret != 0)
return;
/* Check that the child inherited our VL */
child_vl = get_child_rdvl(data);
if (child_vl != data->min_vl) {
ksft_test_result_fail("%s is %d but child VL is %d\n",
data->default_vl_file,
data->min_vl, child_vl);
return;
}
ksft_test_result_pass("%s vector length was inherited\n", data->name);
file_write_integer(data->default_vl_file, data->default_vl);
}
/* _ONEXEC takes effect only in the child process */
static void prctl_set_onexec(struct vec_data *data)
{
int ret, child_vl;
if (data->min_vl == data->max_vl) {
ksft_test_result_skip("%s only one VL supported\n",
data->name);
return;
}
/* Set a known value for the default and our current VL */
ret = file_write_integer(data->default_vl_file, data->max_vl);
if (ret != 0)
return;
ret = prctl(data->prctl_set, data->max_vl);
if (ret < 0) {
ksft_test_result_fail("%s prctl set failed for %d: %d (%s)\n",
data->name, data->min_vl,
errno, strerror(errno));
return;
}
/* Set a different value for the child to have on exec */
ret = prctl(data->prctl_set, data->min_vl | PR_SVE_SET_VL_ONEXEC);
if (ret < 0) {
ksft_test_result_fail("%s prctl set failed for %d: %d (%s)\n",
data->name, data->min_vl,
errno, strerror(errno));
return;
}
/* Our current VL should stay the same */
if (data->rdvl() != data->max_vl) {
ksft_test_result_fail("%s VL changed by _ONEXEC prctl()\n",
data->name);
return;
}
/* Check that the child inherited our VL */
child_vl = get_child_rdvl(data);
if (child_vl != data->min_vl) {
ksft_test_result_fail("Set %d _ONEXEC but child VL is %d\n",
data->min_vl, child_vl);
return;
}
ksft_test_result_pass("%s vector length set on exec\n", data->name);
file_write_integer(data->default_vl_file, data->default_vl);
}
typedef void (*test_type)(struct vec_data *);
static const test_type tests[] = {
/*
* The default/min/max tests must be first and in this order
* to provide data for other tests.
*/
proc_read_default,
proc_write_min,
proc_write_max,
prctl_get,
prctl_set,
prctl_set_no_child,
prctl_set_for_child,
prctl_set_onexec,
};
int main(void)
{
int i, j;
ksft_print_header();
ksft_set_plan(ARRAY_SIZE(tests) * ARRAY_SIZE(vec_data));
for (i = 0; i < ARRAY_SIZE(vec_data); i++) {
struct vec_data *data = &vec_data[i];
unsigned long supported;
supported = getauxval(data->hwcap_type) & data->hwcap;
for (j = 0; j < ARRAY_SIZE(tests); j++) {
if (supported)
tests[j](data);
else
ksft_test_result_skip("%s not supported\n",
data->name);
}
}
ksft_exit_pass();
}