linux/tools/testing/selftests/sched_ext, branch master

selftests/sched_ext: Fix wrong DSQ ID in peek_dsq error message

2026-04-10T09:00:44Z

The error path after scx_bpf_create_dsq(real_dsq_id, ...) was reporting test_dsq_id instead of real_dsq_id in the error message, which would mislead debugging. Signed-off-by: fangqiurong Signed-off-by: Tejun Heo

selftests/sched_ext: Improve runner error reporting for invalid arguments

2026-04-09T01:20:44Z

Report an error for './runner foo' (positional arg instead of -t) and for './runner -t foo' when the filter matches no tests. Previously both cases produced no error output. Pre-scan the test list before the main loop so the error is reported immediately, avoiding spurious SKIP output from '-s' when no tests match. Signed-off-by: Cheng-Yang Chou Signed-off-by: Tejun Heo

Merge branch 'for-7.0-fixes' into for-7.1

2026-03-30T19:02:05Z

Conflict in kernel/sched/ext.c init_sched_ext_class() between: 415cb193bb97 ("sched_ext: Fix SCX_KICK_WAIT deadlock by deferring wait to balance callback") which adds cpus_to_sync cpumask allocation, and: 84b1a0ea0b7c ("sched_ext: Implement scx_bpf_dsq_reenq() for user DSQs") 8c1b9453fde6 ("sched_ext: Convert deferred_reenq_locals from llist to regular list") which add deferred_reenq init code at the same location. Both are independent additions. Include both. Signed-off-by: Tejun Heo

selftests/sched_ext: Add cyclic SCX_KICK_WAIT stress test

2026-03-30T18:37:55Z

Add a test that creates a 3-CPU kick_wait cycle (A->B->C->A). A BPF scheduler kicks the next CPU in the ring with SCX_KICK_WAIT on every enqueue while userspace workers generate continuous scheduling churn via sched_yield(). Without the preceding fix, this hangs the machine within seconds. Signed-off-by: Tejun Heo Reviewed-by: Christian Loehle Tested-by: Christian Loehle

Revert "selftests/sched_ext: Add tests for SCX_ENQ_IMMED and scx_bpf_dsq_reenq()"

2026-03-27T00:45:37Z

This reverts commit c50dcf533149. The tests are superficial, likely AI-generated slop, and flaky. They don't add actual value and just churn the selftests. Signed-off-by: Tejun Heo

selftests/sched_ext: Skip rt_stall on older kernels and list skipped tests

2026-03-24T20:33:25Z

rt_stall tests the ext DL server which was introduced in commit cd959a356205 ("sched_ext: Add a DL server for sched_ext tasks"). On older kernels that lack this feature, the test calls ksft_exit_fail() internally which terminates the entire runner process, preventing subsequent tests from running. Add a guard in setup() that checks for the ext_server field in struct rq via __COMPAT_struct_has_field() and returns SCX_TEST_SKIP if not present. Also print the names of skipped tests in the results summary, mirroring the existing behavior for failed tests. Signed-off-by: Cheng-Yang Chou Signed-off-by: Tejun Heo

selftests/sched_ext: Add tests for SCX_ENQ_IMMED and scx_bpf_dsq_reenq()

2026-03-23T00:29:42Z

Add three selftests covering features introduced in v7.1: - dsq_reenq: Verify scx_bpf_dsq_reenq() on user DSQs triggers ops.enqueue() with SCX_ENQ_REENQ and SCX_TASK_REENQ_KFUNC in p->scx.flags. - enq_immed: Verify SCX_OPS_ALWAYS_ENQ_IMMED slow path where tasks dispatched to a busy CPU's local DSQ are re-enqueued through ops.enqueue() with SCX_TASK_REENQ_IMMED. - consume_immed: Verify SCX_ENQ_IMMED via the consume path using scx_bpf_dsq_move_to_local___v2() with explicit SCX_ENQ_IMMED. All three tests skip gracefully on kernels that predate the required features by checking availability via __COMPAT_has_ksym() / __COMPAT_read_enum() before loading. Signed-off-by: zhidao su Signed-off-by: Tejun Heo

selftests/sched_ext: Return non-zero exit code on test failure

2026-03-21T18:35:51Z

runner.c always returned 0 regardless of test results. The kselftest framework (tools/testing/selftests/kselftest/runner.sh) invokes the runner binary and treats a non-zero exit code as a test failure; with the old code, failed sched_ext tests were silently hidden from the parent harness even though individual "not ok" TAP lines were emitted. Return 1 when at least one test failed, 0 when all tests passed or were skipped. Signed-off-by: zhidao su Acked-by: Andrea Righi Signed-off-by: Tejun Heo

selftests/sched_ext: Show failed test names in summary

2026-03-17T17:46:57Z

When tests fail, the runner only printed the failure count, making it hard to tell which tests failed without scrolling through output. Track failed test names in an array and print them after the summary so failures are immediately visible at the end of the run. Signed-off-by: Cheng-Yang Chou Signed-off-by: Tejun Heo

sched_ext: Update selftests to drop ops.cpu_acquire/release()

2026-03-15T08:54:05Z

ops.cpu_acquire/release() are deprecated by commit a3f5d4822253 ("sched_ext: Allow scx_bpf_reenqueue_local() to be called from anywhere") in favor of handling CPU preemption via the sched_switch tracepoint. In the maximal selftest, replace the cpu_acquire/release stubs with a minimal sched_switch TP program. Attach all non-struct_ops programs (including the new TP) via maximal__attach() after disabling auto-attach for the maximal_ops struct_ops map, which is managed manually in run(). Apply the same fix to reload_loop, which also uses the maximal skeleton. Signed-off-by: Cheng-Yang Chou Reviewed-by: Andrea Righi Signed-off-by: Tejun Heo