[patch 10/10] selftests/rseq: Expand for optimized RSEQ ABI v2

Thomas Gleixner
2026-04-28T23:34:28Z

Update the selftests so they are executed for legacy (32 bytes RSEQ region)
and optimized RSEQ ABI v2 mode.

Fixes: d6200245c75e ("rseq: Allow registering RSEQ with slice extension")
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Cc: stable@vger.kernel.org
---
tools/testing/selftests/rseq/Makefile | 7 ++-
tools/testing/selftests/rseq/check_optimized.c | 17 +++++++++
tools/testing/selftests/rseq/param_test.c | 22 +++++++----
tools/testing/selftests/rseq/run_param_test.sh | 39 +++++++++++++++++++++
tools/testing/selftests/rseq/run_timeslice_test.sh | 14 +++++++
tools/testing/selftests/rseq/slice_test.c | 2 -
6 files changed, 89 insertions(+), 12 deletions(-)

--- a/tools/testing/selftests/rseq/Makefile
+++ b/tools/testing/selftests/rseq/Makefile
@@ -17,11 +17,11 @@ OVERRIDE_TARGETS = 1
TEST_GEN_PROGS = basic_test basic_percpu_ops_test basic_percpu_ops_mm_cid_test param_test \
param_test_benchmark param_test_compare_twice param_test_mm_cid \
param_test_mm_cid_benchmark param_test_mm_cid_compare_twice \
- syscall_errors_test slice_test legacy_check
+ syscall_errors_test slice_test legacy_check check_optimized

TEST_GEN_PROGS_EXTENDED = librseq.so

-TEST_PROGS = run_param_test.sh run_syscall_errors_test.sh run_legacy_check.sh
+TEST_PROGS = run_param_test.sh run_syscall_errors_test.sh run_legacy_check.sh run_timeslice_test.sh

TEST_FILES := settings

@@ -62,3 +62,6 @@ include ../lib.mk

$(OUTPUT)/slice_test: slice_test.c $(TEST_GEN_PROGS_EXTENDED) rseq.h rseq-*.h
$(CC) $(CFLAGS) $< $(LDLIBS) -lrseq -o $@
+
+$(OUTPUT)/check_optimized: check_optimized.c $(TEST_GEN_PROGS_EXTENDED) rseq.h rseq-*.h
+ $(CC) $(CFLAGS) $< $(LDLIBS) -lrseq -o $@
--- /dev/null
+++ b/tools/testing/selftests/rseq/check_optimized.c
@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: LGPL-2.1
+#define _GNU_SOURCE
+#include <assert.h>
+#include <sched.h>
+#include <signal.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/time.h>
+
+#include "rseq.h"
+
+int main(int argc, char **argv)
+{
+ if (__rseq_register_current_thread(true, false))
+ return -1;
+ return 0;
+}
--- a/tools/testing/selftests/rseq/param_test.c
+++ b/tools/testing/selftests/rseq/param_test.c
@@ -38,7 +38,7 @@ static int opt_modulo, verbose;
static int opt_yield, opt_signal, opt_sleep,
opt_disable_rseq, opt_threads = 200,
opt_disable_mod = 0, opt_test = 's';
-
+static bool opt_rseq_legacy;
static long long opt_reps = 5000;

static __thread __attribute__((tls_model("initial-exec")))
@@ -481,7 +481,7 @@ void *test_percpu_spinlock_thread(void *
long long i, reps;

if (!opt_disable_rseq && thread_data->reg &&
- rseq_register_current_thread())
+ __rseq_register_current_thread(true, opt_rseq_legacy))
abort();
reps = thread_data->reps;
for (i = 0; i < reps; i++) {
@@ -558,7 +558,7 @@ void *test_percpu_inc_thread(void *arg)
long long i, reps;

if (!opt_disable_rseq && thread_data->reg &&
- rseq_register_current_thread())
+ __rseq_register_current_thread(true, opt_rseq_legacy))
abort();
reps = thread_data->reps;
for (i = 0; i < reps; i++) {
@@ -712,7 +712,7 @@ void *test_percpu_list_thread(void *arg)
long long i, reps;
struct percpu_list *list = (struct percpu_list *)arg;

- if (!opt_disable_rseq && rseq_register_current_thread())
+ if (!opt_disable_rseq && __rseq_register_current_thread(true, opt_rseq_legacy))
abort();

reps = opt_reps;
@@ -895,7 +895,7 @@ void *test_percpu_buffer_thread(void *ar
long long i, reps;
struct percpu_buffer *buffer = (struct percpu_buffer *)arg;

- if (!opt_disable_rseq && rseq_register_current_thread())
+ if (!opt_disable_rseq && __rseq_register_current_thread(true, opt_rseq_legacy))
abort();

reps = opt_reps;
@@ -1105,7 +1105,7 @@ void *test_percpu_memcpy_buffer_thread(v
long long i, reps;
struct percpu_memcpy_buffer *buffer = (struct percpu_memcpy_buffer *)arg;

- if (!opt_disable_rseq && rseq_register_current_thread())
+ if (!opt_disable_rseq && __rseq_register_current_thread(true, opt_rseq_legacy))
abort();

reps = opt_reps;
@@ -1258,7 +1258,7 @@ void *test_membarrier_worker_thread(void
const int iters = opt_reps;
int i;

- if (rseq_register_current_thread()) {
+ if (__rseq_register_current_thread(true, opt_rseq_legacy)) {
fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n",
errno, strerror(errno));
abort();
@@ -1323,7 +1323,7 @@ void *test_membarrier_manager_thread(voi
intptr_t expect_a = 0, expect_b = 0;
int cpu_a = 0, cpu_b = 0;

- if (rseq_register_current_thread()) {
+ if (__rseq_register_current_thread(true, opt_rseq_legacy)) {
fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n",
errno, strerror(errno));
abort();
@@ -1475,6 +1475,7 @@ static void show_usage(int argc, char **
printf(" [-D M] Disable rseq for each M threads\n");
printf(" [-T test] Choose test: (s)pinlock, (l)ist, (b)uffer, (m)emcpy, (i)ncrement, membarrie(r)\n");
printf(" [-M] Push into buffer and memcpy buffer with memory barriers.\n");
+ printf(" [-O] Test with optimized RSEQ\n");
printf(" [-v] Verbose output.\n");
printf(" [-h] Show this help.\n");
printf("\n");
@@ -1602,6 +1603,9 @@ int main(int argc, char **argv)
case 'M':
opt_mo = RSEQ_MO_RELEASE;
break;
+ case 'L':
+ opt_rseq_legacy = true;
+ break;
default:
show_usage(argc, argv);
goto error;
@@ -1618,7 +1622,7 @@ int main(int argc, char **argv)
if (set_signal_handler())
goto error;

- if (!opt_disable_rseq && rseq_register_current_thread())
+ if (!opt_disable_rseq && __rseq_register_current_thread(true, opt_rseq_legacy))
goto error;
if (!opt_disable_rseq && !rseq_validate_cpu_id()) {
fprintf(stderr, "Error: cpu id getter unavailable\n");
--- a/tools/testing/selftests/rseq/run_param_test.sh
+++ b/tools/testing/selftests/rseq/run_param_test.sh
@@ -34,6 +34,11 @@ REPS=1000
SLOW_REPS=100
NR_THREADS=$((6*${NR_CPUS}))

+# Prevent GLIBC from registering RSEQ so the selftest can run in legacy and
+# performance optimized mode.
+GLIBC_TUNABLES="${GLIBC_TUNABLES:-}:glibc.pthread.rseq=0"
+export GLIBC_TUNABLES
+
function do_tests()
{
local i=0
@@ -103,6 +108,40 @@ function inject_blocking()
NR_LOOPS=
}

+echo "Testing in legacy RSEQ mode"
+echo "Yield injection (25%)"
+inject_blocking -m 4 -y -L
+
+echo "Yield injection (50%)"
+inject_blocking -m 2 -y -L
+
+echo "Yield injection (100%)"
+inject_blocking -m 1 -y -L
+
+echo "Kill injection (25%)"
+inject_blocking -m 4 -k -L
+
+echo "Kill injection (50%)"
+inject_blocking -m 2 -k -L
+
+echo "Kill injection (100%)"
+inject_blocking -m 1 -k -L
+
+echo "Sleep injection (1ms, 25%)"
+inject_blocking -m 4 -s 1 -L
+
+echo "Sleep injection (1ms, 50%)"
+inject_blocking -m 2 -s 1 -L
+
+echo "Sleep injection (1ms, 100%)"
+inject_blocking -m 1 -s 1 -L
+
+./check_optimized || {
+ echo "Skipping optimized RSEQ mode test. Not supported";
+ exit 0
+}
+
+echo "Testing in optimized RSEQ mode"
echo "Yield injection (25%)"
inject_blocking -m 4 -y

--- /dev/null
+++ b/tools/testing/selftests/rseq/run_timeslice_test.sh
@@ -0,0 +1,14 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0+
+
+# Prevent GLIBC from registering RSEQ so the selftest can run in legacy
+# and performance optimized mode.
+GLIBC_TUNABLES="${GLIBC_TUNABLES:-}:glibc.pthread.rseq=0"
+export GLIBC_TUNABLES
+
+./check_optimized || {
+ echo "Skipping optimized RSEQ mode test. Not supported";
+ exit 0
+}
+
+./slice_test
--- a/tools/testing/selftests/rseq/slice_test.c
+++ b/tools/testing/selftests/rseq/slice_test.c
@@ -124,7 +124,7 @@ FIXTURE_SETUP(slice_ext)
{
cpu_set_t affinity;

- if (rseq_register_current_thread())
+ if (__rseq_register_current_thread(true, false))
SKIP(return, "RSEQ not supported\n");

if (prctl(PR_RSEQ_SLICE_EXTENSION, PR_RSEQ_SLICE_EXTENSION_SET,