// SPDX-License-Identifier: GPL-2.0-only
#include <linux/sched.h>
#include <linux/wait.h>
#define SYS_TPIDR2 "S3_3_C13_C0_5"
#define EXPECTED_TESTS 5
static void putstr(const char *str)
{
write(1, str, strlen(str));
}
static void putnum(unsigned int num)
{
char c;
if (num / 10)
putnum(num / 10);
c = '0' + (num % 10);
write(1, &c, 1);
}
static int tests_run;
static int tests_passed;
static int tests_failed;
static int tests_skipped;
static void set_tpidr2(uint64_t val)
{
asm volatile (
"msr " SYS_TPIDR2 ", %0\n"
:
: "r"(val)
: "cc");
}
static uint64_t get_tpidr2(void)
{
uint64_t val;
asm volatile (
"mrs %0, " SYS_TPIDR2 "\n"
: "=r"(val)
:
: "cc");
return val;
}
static void print_summary(void)
{
if (tests_passed + tests_failed + tests_skipped != EXPECTED_TESTS)
putstr("# UNEXPECTED TEST COUNT: ");
putstr("# Totals: pass:");
putnum(tests_passed);
putstr(" fail:");
putnum(tests_failed);
putstr(" xfail:0 xpass:0 skip:");
putnum(tests_skipped);
putstr(" error:0\n");
}
/* Processes should start with TPIDR2 == 0 */
static int default_value(void)
{
return get_tpidr2() == 0;
}
/* If we set TPIDR2 we should read that value */
static int write_read(void)
{
set_tpidr2(getpid());
return getpid() == get_tpidr2();
}
/* If we set a value we should read the same value after scheduling out */
static int write_sleep_read(void)
{
set_tpidr2(getpid());
msleep(100);
return getpid() == get_tpidr2();
}
/*
* If we fork the value in the parent should be unchanged and the
* child should start with the same value and be able to set its own
* value.
*/
static int write_fork_read(void)
{
pid_t newpid, waiting, oldpid;
int status;
set_tpidr2(getpid());
oldpid = getpid();
newpid = fork();
if (newpid == 0) {
/* In child */
if (get_tpidr2() != oldpid) {
putstr("# TPIDR2 changed in child: ");
putnum(get_tpidr2());
putstr("\n");
exit(0);
}
set_tpidr2(getpid());
if (get_tpidr2() == getpid()) {
exit(1);
} else {
putstr("# Failed to set TPIDR2 in child\n");
exit(0);
}
}
if (newpid < 0) {
putstr("# fork() failed: -");
putnum(-newpid);
putstr("\n");
return 0;
}
for (;;) {
waiting = waitpid(newpid, &status, 0);
if (waiting < 0) {
if (errno == EINTR)
continue;
putstr("# waitpid() failed: ");
putnum(errno);
putstr("\n");
return 0;
}
if (waiting != newpid) {
putstr("# waitpid() returned wrong PID\n");
return 0;
}
if (!WIFEXITED(status)) {
putstr("# child did not exit\n");
return 0;
}
if (getpid() != get_tpidr2()) {
putstr("# TPIDR2 corrupted in parent\n");
return 0;
}
return WEXITSTATUS(status);
}
}
/*
* sys_clone() has a lot of per architecture variation so just define
* it here rather than adding it to nolibc, plus the raw API is a
* little more convenient for this test.
*/
static int sys_clone(unsigned long clone_flags, unsigned long newsp,
int *parent_tidptr, unsigned long tls,
int *child_tidptr)
{
return my_syscall5(__NR_clone, clone_flags, newsp, parent_tidptr, tls,
child_tidptr);
}
/*
* If we clone with CLONE_SETTLS then the value in the parent should
* be unchanged and the child should start with zero and be able to
* set its own value.
*/
static int write_clone_read(void)
{
int parent_tid, child_tid;
pid_t parent, waiting;
int ret, status;
parent = getpid();
set_tpidr2(parent);
ret = sys_clone(CLONE_SETTLS, 0, &parent_tid, 0, &child_tid);
if (ret == -1) {
putstr("# clone() failed\n");
putnum(errno);
putstr("\n");
return 0;
}
if (ret == 0) {
/* In child */
if (get_tpidr2() != 0) {
putstr("# TPIDR2 non-zero in child: ");
putnum(get_tpidr2());
putstr("\n");
exit(0);
}
if (gettid() == 0)
putstr("# Child TID==0\n");
set_tpidr2(gettid());
if (get_tpidr2() == gettid()) {
exit(1);
} else {
putstr("# Failed to set TPIDR2 in child\n");
exit(0);
}
}
for (;;) {
waiting = wait4(ret, &status, __WCLONE, NULL);
if (waiting < 0) {
if (errno == EINTR)
continue;
putstr("# wait4() failed: ");
putnum(errno);
putstr("\n");
return 0;
}
if (waiting != ret) {
putstr("# wait4() returned wrong PID ");
putnum(waiting);
putstr("\n");
return 0;
}
if (!WIFEXITED(status)) {
putstr("# child did not exit\n");
return 0;
}
if (parent != get_tpidr2()) {
putstr("# TPIDR2 corrupted in parent\n");
return 0;
}
return WEXITSTATUS(status);
}
}
#define run_test(name) \
if (name()) { \
tests_passed++; \
} else { \
tests_failed++; \
putstr("not "); \
} \
putstr("ok "); \
putnum(++tests_run); \
putstr(" " #name "\n");
#define skip_test(name) \
tests_skipped++; \
putstr("ok "); \
putnum(++tests_run); \
putstr(" # SKIP " #name "\n");
int main(int argc, char **argv)
{
int ret;
putstr("TAP version 13\n");
putstr("1..");
putnum(EXPECTED_TESTS);
putstr("\n");
putstr("# PID: ");
putnum(getpid());
putstr("\n");
/*
* This test is run with nolibc which doesn't support hwcap and
* it's probably disproportionate to implement so instead check
* for the default vector length configuration in /proc.
*/
ret = open("/proc/sys/abi/sme_default_vector_length", O_RDONLY, 0);
if (ret >= 0) {
run_test(default_value);
run_test(write_read);
run_test(write_sleep_read);
run_test(write_fork_read);
run_test(write_clone_read);
} else {
putstr("# SME support not present\n");
skip_test(default_value);
skip_test(write_read);
skip_test(write_sleep_read);
skip_test(write_fork_read);
skip_test(write_clone_read);
}
print_summary();
return 0;
}
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