A task in the kernel (task_mm_cid_work) runs somewhat periodically to
compact the mm_cid for each process. Add a test to validate that it runs
correctly and timely.
The test spawns 1 thread pinned to each CPU, then each thread, including
the main one, runs in short bursts for some time. During this period, the
mm_cids should be spanning all numbers between 0 and nproc.
At the end of this phase, a thread with high enough mm_cid (>= nproc/2)
is selected to be the new leader, all other threads terminate.
After some time, the only running thread should see 0 as mm_cid, if that
doesn't happen, the compaction mechanism didn't work and the test fails.
The test never fails if only 1 core is available, in which case, we
cannot test anything as the only available mm_cid is 0.
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com>
Acked-by: Shuah Khan <skhan(a)linuxfoundation.org>
Signed-off-by: Gabriele Monaco <gmonaco(a)redhat.com>
---
tools/testing/selftests/rseq/.gitignore | 1 +
tools/testing/selftests/rseq/Makefile | 2 +-
.../selftests/rseq/mm_cid_compaction_test.c | 200 ++++++++++++++++++
3 files changed, 202 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/rseq/mm_cid_compaction_test.c
diff --git a/tools/testing/selftests/rseq/.gitignore b/tools/testing/selftests/rseq/.gitignore
index 0fda241fa62b0..b3920c59bf401 100644
--- a/tools/testing/selftests/rseq/.gitignore
+++ b/tools/testing/selftests/rseq/.gitignore
@@ -3,6 +3,7 @@ basic_percpu_ops_test
basic_percpu_ops_mm_cid_test
basic_test
basic_rseq_op_test
+mm_cid_compaction_test
param_test
param_test_benchmark
param_test_compare_twice
diff --git a/tools/testing/selftests/rseq/Makefile b/tools/testing/selftests/rseq/Makefile
index 0d0a5fae59547..bc4d940f66d40 100644
--- a/tools/testing/selftests/rseq/Makefile
+++ b/tools/testing/selftests/rseq/Makefile
@@ -17,7 +17,7 @@ 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
+ syscall_errors_test mm_cid_compaction_test
TEST_GEN_PROGS_EXTENDED = librseq.so
diff --git a/tools/testing/selftests/rseq/mm_cid_compaction_test.c b/tools/testing/selftests/rseq/mm_cid_compaction_test.c
new file mode 100644
index 0000000000000..7ddde3b657dd6
--- /dev/null
+++ b/tools/testing/selftests/rseq/mm_cid_compaction_test.c
@@ -0,0 +1,200 @@
+// SPDX-License-Identifier: LGPL-2.1
+#define _GNU_SOURCE
+#include <assert.h>
+#include <pthread.h>
+#include <sched.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stddef.h>
+
+#include "../kselftest.h"
+#include "rseq.h"
+
+#define VERBOSE 0
+#define printf_verbose(fmt, ...) \
+ do { \
+ if (VERBOSE) \
+ printf(fmt, ##__VA_ARGS__); \
+ } while (0)
+
+/* 0.5 s */
+#define RUNNER_PERIOD 500000
+/* Number of runs before we terminate or get the token */
+#define THREAD_RUNS 5
+
+/*
+ * Number of times we check that the mm_cid were compacted.
+ * Checks are repeated every RUNNER_PERIOD.
+ */
+#define MM_CID_COMPACT_TIMEOUT 10
+
+struct thread_args {
+ int cpu;
+ int num_cpus;
+ pthread_mutex_t *token;
+ pthread_barrier_t *barrier;
+ pthread_t *tinfo;
+ struct thread_args *args_head;
+};
+
+static void __noreturn *thread_runner(void *arg)
+{
+ struct thread_args *args = arg;
+ int i, ret, curr_mm_cid;
+ cpu_set_t cpumask;
+
+ CPU_ZERO(&cpumask);
+ CPU_SET(args->cpu, &cpumask);
+ ret = pthread_setaffinity_np(pthread_self(), sizeof(cpumask), &cpumask);
+ if (ret) {
+ errno = ret;
+ perror("Error: failed to set affinity");
+ abort();
+ }
+ pthread_barrier_wait(args->barrier);
+
+ for (i = 0; i < THREAD_RUNS; i++)
+ usleep(RUNNER_PERIOD);
+ curr_mm_cid = rseq_current_mm_cid();
+ /*
+ * We select one thread with high enough mm_cid to be the new leader.
+ * All other threads (including the main thread) will terminate.
+ * After some time, the mm_cid of the only remaining thread should
+ * converge to 0, if not, the test fails.
+ */
+ if (curr_mm_cid >= args->num_cpus / 2 &&
+ !pthread_mutex_trylock(args->token)) {
+ printf_verbose(
+ "cpu%d has mm_cid=%d and will be the new leader.\n",
+ sched_getcpu(), curr_mm_cid);
+ for (i = 0; i < args->num_cpus; i++) {
+ if (args->tinfo[i] == pthread_self())
+ continue;
+ ret = pthread_join(args->tinfo[i], NULL);
+ if (ret) {
+ errno = ret;
+ perror("Error: failed to join thread");
+ abort();
+ }
+ }
+ pthread_barrier_destroy(args->barrier);
+ free(args->tinfo);
+ free(args->token);
+ free(args->barrier);
+ free(args->args_head);
+
+ for (i = 0; i < MM_CID_COMPACT_TIMEOUT; i++) {
+ curr_mm_cid = rseq_current_mm_cid();
+ printf_verbose("run %d: mm_cid=%d on cpu%d.\n", i,
+ curr_mm_cid, sched_getcpu());
+ if (curr_mm_cid == 0)
+ exit(EXIT_SUCCESS);
+ usleep(RUNNER_PERIOD);
+ }
+ exit(EXIT_FAILURE);
+ }
+ printf_verbose("cpu%d has mm_cid=%d and is going to terminate.\n",
+ sched_getcpu(), curr_mm_cid);
+ pthread_exit(NULL);
+}
+
+int test_mm_cid_compaction(void)
+{
+ cpu_set_t affinity;
+ int i, j, ret = 0, num_threads;
+ pthread_t *tinfo;
+ pthread_mutex_t *token;
+ pthread_barrier_t *barrier;
+ struct thread_args *args;
+
+ sched_getaffinity(0, sizeof(affinity), &affinity);
+ num_threads = CPU_COUNT(&affinity);
+ tinfo = calloc(num_threads, sizeof(*tinfo));
+ if (!tinfo) {
+ perror("Error: failed to allocate tinfo");
+ return -1;
+ }
+ args = calloc(num_threads, sizeof(*args));
+ if (!args) {
+ perror("Error: failed to allocate args");
+ ret = -1;
+ goto out_free_tinfo;
+ }
+ token = malloc(sizeof(*token));
+ if (!token) {
+ perror("Error: failed to allocate token");
+ ret = -1;
+ goto out_free_args;
+ }
+ barrier = malloc(sizeof(*barrier));
+ if (!barrier) {
+ perror("Error: failed to allocate barrier");
+ ret = -1;
+ goto out_free_token;
+ }
+ if (num_threads == 1) {
+ fprintf(stderr, "Cannot test on a single cpu. "
+ "Skipping mm_cid_compaction test.\n");
+ /* only skipping the test, this is not a failure */
+ goto out_free_barrier;
+ }
+ pthread_mutex_init(token, NULL);
+ ret = pthread_barrier_init(barrier, NULL, num_threads);
+ if (ret) {
+ errno = ret;
+ perror("Error: failed to initialise barrier");
+ goto out_free_barrier;
+ }
+ for (i = 0, j = 0; i < CPU_SETSIZE && j < num_threads; i++) {
+ if (!CPU_ISSET(i, &affinity))
+ continue;
+ args[j].num_cpus = num_threads;
+ args[j].tinfo = tinfo;
+ args[j].token = token;
+ args[j].barrier = barrier;
+ args[j].cpu = i;
+ args[j].args_head = args;
+ if (!j) {
+ /* The first thread is the main one */
+ tinfo[0] = pthread_self();
+ ++j;
+ continue;
+ }
+ ret = pthread_create(&tinfo[j], NULL, thread_runner, &args[j]);
+ if (ret) {
+ errno = ret;
+ perror("Error: failed to create thread");
+ abort();
+ }
+ ++j;
+ }
+ printf_verbose("Started %d threads.\n", num_threads);
+
+ /* Also main thread will terminate if it is not selected as leader */
+ thread_runner(&args[0]);
+
+ /* only reached in case of errors */
+out_free_barrier:
+ free(barrier);
+out_free_token:
+ free(token);
+out_free_args:
+ free(args);
+out_free_tinfo:
+ free(tinfo);
+
+ return ret;
+}
+
+int main(int argc, char **argv)
+{
+ if (!rseq_mm_cid_available()) {
+ fprintf(stderr, "Error: rseq_mm_cid unavailable\n");
+ return -1;
+ }
+ if (test_mm_cid_compaction())
+ return -1;
+ return 0;
+}
--
2.50.0
Some cleanups for the vDSO selftests.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh(a)linutronix.de>
---
Thomas Weißschuh (5):
selftests: vDSO: vdso_test_abi: Use ksft_finished()
selftests: vDSO: vdso_test_abi: Drop clock availability tests
selftests: vDSO: vdso_test_abi: Use explicit indices for name array
selftests: vDSO: vdso_test_abi: Test CPUTIME clocks
selftests: vDSO: Drop vdso_test_clock_getres
tools/testing/selftests/vDSO/Makefile | 2 -
tools/testing/selftests/vDSO/vdso_test_abi.c | 57 +++-------
.../selftests/vDSO/vdso_test_clock_getres.c | 123 ---------------------
3 files changed, 17 insertions(+), 165 deletions(-)
---
base-commit: 437079605c26dc7c98586580a8c01b5f7f746a79
change-id: 20250707-vdso-tests-fixes-7e4ddffd7f27
Best regards,
--
Thomas Weißschuh <thomas.weissschuh(a)linutronix.de>
Arguments passed into WEXITSTATUS() should have been initialized earlier.
Otherwise following warning show up while building platform selftests on
arm64. Hence just zero out all the relevant local variables to avoid the
build warning.
Warning: ‘status’ may be used uninitialized in this function [-Wmaybe-uninitialized]
Cc: Catalin Marinas <catalin.marinas(a)arm.com>
Cc: Will Deacon <will(a)kernel.org>
Cc: Shuah Khan <shuah(a)kernel.org>
Cc: Mark Brown <broonie(a)kernel.org>
Cc: linux-arm-kernel(a)lists.infradead.org
Cc: linux-kselftest(a)vger.kernel.org
Cc: linux-kernel(a)vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual(a)arm.com>
---
This applies on v6.16-rc3
tools/testing/selftests/arm64/abi/tpidr2.c | 2 +-
tools/testing/selftests/arm64/fp/za-fork.c | 2 +-
tools/testing/selftests/arm64/gcs/basic-gcs.c | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/arm64/abi/tpidr2.c b/tools/testing/selftests/arm64/abi/tpidr2.c
index eb19dcc37a755..389a60e5feabf 100644
--- a/tools/testing/selftests/arm64/abi/tpidr2.c
+++ b/tools/testing/selftests/arm64/abi/tpidr2.c
@@ -96,7 +96,7 @@ static int write_sleep_read(void)
static int write_fork_read(void)
{
pid_t newpid, waiting, oldpid;
- int status;
+ int status = 0;
set_tpidr2(getpid());
diff --git a/tools/testing/selftests/arm64/fp/za-fork.c b/tools/testing/selftests/arm64/fp/za-fork.c
index 587b946482226..6098beb3515a0 100644
--- a/tools/testing/selftests/arm64/fp/za-fork.c
+++ b/tools/testing/selftests/arm64/fp/za-fork.c
@@ -24,7 +24,7 @@ int verify_fork(void);
int fork_test_c(void)
{
pid_t newpid, waiting;
- int child_status, parent_result;
+ int child_status = 0, parent_result;
newpid = fork();
if (newpid == 0) {
diff --git a/tools/testing/selftests/arm64/gcs/basic-gcs.c b/tools/testing/selftests/arm64/gcs/basic-gcs.c
index 3fb9742342a34..2b350b6b7e12c 100644
--- a/tools/testing/selftests/arm64/gcs/basic-gcs.c
+++ b/tools/testing/selftests/arm64/gcs/basic-gcs.c
@@ -240,7 +240,7 @@ static bool map_guarded_stack(void)
static bool test_fork(void)
{
unsigned long child_mode;
- int ret, status;
+ int ret, status = 0;
pid_t pid;
bool pass = true;
--
2.30.2
glibc does not define SYS_futex for 32-bit architectures using 64-bit
time_t e.g. riscv32, therefore this test fails to compile since it does not
find SYS_futex in C library headers. Define SYS_futex as SYS_futex_time64
in this situation to ensure successful compilation and compatibility.
Signed-off-by: Cynthia Huang <cynthia(a)andestech.com>
Signed-off-by: Ben Zong-You Xie <ben717(a)andestech.com>
---
Changes since v1:
- Fix the SOB chain
v1 : https://lore.kernel.org/all/20250527093536.3646143-1-ben717@andestech.com/
---
tools/testing/selftests/futex/include/futextest.h | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/tools/testing/selftests/futex/include/futextest.h b/tools/testing/selftests/futex/include/futextest.h
index ddbcfc9b7bac..7a5fd1d5355e 100644
--- a/tools/testing/selftests/futex/include/futextest.h
+++ b/tools/testing/selftests/futex/include/futextest.h
@@ -47,6 +47,17 @@ typedef volatile u_int32_t futex_t;
FUTEX_PRIVATE_FLAG)
#endif
+/*
+ * SYS_futex is expected from system C library, in glibc some 32-bit
+ * architectures (e.g. RV32) are using 64-bit time_t, therefore it doesn't have
+ * SYS_futex defined but just SYS_futex_time64. Define SYS_futex as
+ * SYS_futex_time64 in this situation to ensure the compilation and the
+ * compatibility.
+ */
+#if !defined(SYS_futex) && defined(SYS_futex_time64)
+#define SYS_futex SYS_futex_time64
+#endif
+
/**
* futex() - SYS_futex syscall wrapper
* @uaddr: address of first futex
--
2.34.1
When an error is encountered by printf() it needs to be reported.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh(a)linutronix.de>
---
Thomas Weißschuh (2):
selftests/nolibc: create /dev/full when running as PID 1
selftests/nolibc: correctly report errors from printf() and friends
tools/include/nolibc/stdio.h | 4 ++--
tools/testing/selftests/nolibc/nolibc-test.c | 27 ++++++++++++++++++++++++++-
2 files changed, 28 insertions(+), 3 deletions(-)
---
base-commit: 1536aa0fb1e09cb50f401ec4852c60f38173d751
change-id: 20250704-nolibc-printf-error-aa54f951c0a4
Best regards,
--
Thomas Weißschuh <thomas.weissschuh(a)linutronix.de>
This picks up from Michal Rostecki's work[0]. Per Michal's guidance I
have omitted Co-authored tags, as the end result is quite different.
Link: https://lore.kernel.org/rust-for-linux/20240819153656.28807-2-vadorovsky@pr… [0]
Closes: https://github.com/Rust-for-Linux/linux/issues/1075
Signed-off-by: Tamir Duberstein <tamird(a)gmail.com>
---
Changes in v13:
- Rebase on v6.16-rc4.
- Link to v12: https://lore.kernel.org/r/20250619-cstr-core-v12-0-80c9c7b45900@gmail.com
Changes in v12:
- Introduce `kernel::fmt::Display` to allow implementations on foreign
types.
- Tidy up doc comment on `str_to_cstr`. (Alice Ryhl).
- Link to v11: https://lore.kernel.org/r/20250530-cstr-core-v11-0-cd9c0cbcb902@gmail.com
Changes in v11:
- Use `quote_spanned!` to avoid `use<'a, T>` and generally reduce manual
token construction.
- Add a commit to simplify `quote_spanned!`.
- Drop first commit in favor of
https://lore.kernel.org/rust-for-linux/20240906164448.2268368-1-paddymills@….
(Miguel Ojeda)
- Correctly handle expressions such as `pr_info!("{a}", a = a = a)`.
(Benno Lossin)
- Avoid dealing with `}}` escapes, which is not needed. (Benno Lossin)
- Revert some unnecessary changes. (Benno Lossin)
- Rename `c_str_avoid_literals!` to `str_to_cstr!`. (Benno Lossin &
Alice Ryhl).
- Link to v10: https://lore.kernel.org/r/20250524-cstr-core-v10-0-6412a94d9d75@gmail.com
Changes in v10:
- Rebase on cbeaa41dfe26b72639141e87183cb23e00d4b0dd.
- Implement Alice's suggestion to use a proc macro to work around orphan
rules otherwise preventing `core::ffi::CStr` to be directly printed
with `{}`.
- Link to v9: https://lore.kernel.org/r/20250317-cstr-core-v9-0-51d6cc522f62@gmail.com
Changes in v9:
- Rebase on rust-next.
- Restore `impl Display for BStr` which exists upstream[1].
- Link: https://doc.rust-lang.org/nightly/std/bstr/struct.ByteStr.html#impl-Display… [1]
- Link to v8: https://lore.kernel.org/r/20250203-cstr-core-v8-0-cb3f26e78686@gmail.com
Changes in v8:
- Move `{from,as}_char_ptr` back to `CStrExt`. This reduces the diff
some.
- Restore `from_bytes_with_nul_unchecked_mut`, `to_cstring`.
- Link to v7: https://lore.kernel.org/r/20250202-cstr-core-v7-0-da1802520438@gmail.com
Changes in v7:
- Rebased on mainline.
- Restore functionality added in commit a321f3ad0a5d ("rust: str: add
{make,to}_{upper,lower}case() to CString").
- Used `diff.algorithm patience` to improve diff readability.
- Link to v6: https://lore.kernel.org/r/20250202-cstr-core-v6-0-8469cd6d29fd@gmail.com
Changes in v6:
- Split the work into several commits for ease of review.
- Restore `{from,as}_char_ptr` to allow building on ARM (see commit
message).
- Add `CStrExt` to `kernel::prelude`. (Alice Ryhl)
- Remove `CStrExt::from_bytes_with_nul_unchecked_mut` and restore
`DerefMut for CString`. (Alice Ryhl)
- Rename and hide `kernel::c_str!` to encourage use of C-String
literals.
- Drop implementation and invocation changes in kunit.rs. (Trevor Gross)
- Drop docs on `Display` impl. (Trevor Gross)
- Rewrite docs in the style of the standard library.
- Restore the `test_cstr_debug` unit tests to demonstrate that the
implementation has changed.
Changes in v5:
- Keep the `test_cstr_display*` unit tests.
Changes in v4:
- Provide the `CStrExt` trait with `display()` method, which returns a
`CStrDisplay` wrapper with `Display` implementation. This addresses
the lack of `Display` implementation for `core::ffi::CStr`.
- Provide `from_bytes_with_nul_unchecked_mut()` method in `CStrExt`,
which might be useful and is going to prevent manual, unsafe casts.
- Fix a typo (s/preffered/prefered/).
Changes in v3:
- Fix the commit message.
- Remove redundant braces in `use`, when only one item is imported.
Changes in v2:
- Do not remove `c_str` macro. While it's preferred to use C-string
literals, there are two cases where `c_str` is helpful:
- When working with macros, which already return a Rust string literal
(e.g. `stringify!`).
- When building macros, where we want to take a Rust string literal as an
argument (for caller's convenience), but still use it as a C-string
internally.
- Use Rust literals as arguments in macros (`new_mutex`, `new_condvar`,
`new_mutex`). Use the `c_str` macro to convert these literals to C-string
literals.
- Use `c_str` in kunit.rs for converting the output of `stringify!` to a
`CStr`.
- Remove `DerefMut` implementation for `CString`.
---
Tamir Duberstein (5):
rust: macros: reduce collections in `quote!` macro
rust: support formatting of foreign types
rust: replace `CStr` with `core::ffi::CStr`
rust: replace `kernel::c_str!` with C-Strings
rust: remove core::ffi::CStr reexport
drivers/block/rnull.rs | 4 +-
drivers/cpufreq/rcpufreq_dt.rs | 5 +-
drivers/gpu/drm/drm_panic_qr.rs | 5 +-
drivers/gpu/drm/nova/driver.rs | 10 +-
drivers/gpu/nova-core/driver.rs | 6 +-
drivers/gpu/nova-core/firmware.rs | 2 +-
drivers/gpu/nova-core/gpu.rs | 4 +-
drivers/gpu/nova-core/nova_core.rs | 2 +-
drivers/net/phy/ax88796b_rust.rs | 8 +-
drivers/net/phy/qt2025.rs | 6 +-
rust/kernel/auxiliary.rs | 6 +-
rust/kernel/block/mq.rs | 2 +-
rust/kernel/clk.rs | 9 +-
rust/kernel/configfs.rs | 14 +-
rust/kernel/cpufreq.rs | 6 +-
rust/kernel/device.rs | 9 +-
rust/kernel/devres.rs | 2 +-
rust/kernel/driver.rs | 4 +-
rust/kernel/drm/device.rs | 4 +-
rust/kernel/drm/driver.rs | 3 +-
rust/kernel/drm/ioctl.rs | 2 +-
rust/kernel/error.rs | 10 +-
rust/kernel/faux.rs | 5 +-
rust/kernel/firmware.rs | 16 +-
rust/kernel/fmt.rs | 89 +++++++
rust/kernel/kunit.rs | 28 +--
rust/kernel/lib.rs | 3 +-
rust/kernel/miscdevice.rs | 5 +-
rust/kernel/net/phy.rs | 12 +-
rust/kernel/of.rs | 5 +-
rust/kernel/pci.rs | 2 +-
rust/kernel/platform.rs | 6 +-
rust/kernel/prelude.rs | 5 +-
rust/kernel/print.rs | 4 +-
rust/kernel/seq_file.rs | 6 +-
rust/kernel/str.rs | 444 ++++++++++------------------------
rust/kernel/sync.rs | 7 +-
rust/kernel/sync/completion.rs | 2 +-
rust/kernel/sync/condvar.rs | 4 +-
rust/kernel/sync/lock.rs | 4 +-
rust/kernel/sync/lock/global.rs | 6 +-
rust/kernel/sync/poll.rs | 1 +
rust/kernel/workqueue.rs | 9 +-
rust/macros/fmt.rs | 99 ++++++++
rust/macros/kunit.rs | 10 +-
rust/macros/lib.rs | 19 ++
rust/macros/module.rs | 2 +-
rust/macros/quote.rs | 111 ++++-----
samples/rust/rust_configfs.rs | 9 +-
samples/rust/rust_driver_auxiliary.rs | 7 +-
samples/rust/rust_driver_faux.rs | 4 +-
samples/rust/rust_driver_pci.rs | 4 +-
samples/rust/rust_driver_platform.rs | 4 +-
samples/rust/rust_misc_device.rs | 3 +-
scripts/rustdoc_test_gen.rs | 6 +-
55 files changed, 543 insertions(+), 521 deletions(-)
---
base-commit: 769e324b66b0d92d04f315d0c45a0f72737c7494
change-id: 20250201-cstr-core-d4b9b69120cf
Best regards,
--
Tamir Duberstein <tamird(a)gmail.com>