kernel/linux.git/tools/testing/selftests/rcutorture, branch master

rcutorture: Add NOCB02 config for nocb poll mode testing

2026-03-30T19:48:14+00:00

Add new rcutorture config NOCB02 that enables rcu_nocb_poll boot parameter combined with CONFIG_RCU_NOCB_CPU to exercise the polling mode code paths in the NOCB implementation. This config exercises poll-mode paths not covered by other configs, where callback invocation uses active polling instead of kthread wakeups. This config is not added to CFLIST to avoid increasing the default test duration; it can be run explicitly when poll-mode testing is needed. Acked-by: Frederic Weisbecker Reviewed-by: Paul E. McKenney Tested-by: Paul E. McKenney Signed-off-by: Joel Fernandes

rcutorture: Add NOCB01 config for RCU_LAZY torture testing

2026-03-30T19:48:14+00:00

Add new rcutorture config NOCB01 that enables CONFIG_RCU_LAZY combined with CONFIG_RCU_NOCB_CPU to exercise the lazy callback code paths in the NOCB implementation. This config exercises lazy callback paths not covered by other configs, including lazy-only wake and lazy defer logic. This config is not added to CFLIST to avoid increasing the default test duration; it can be run explicitly when lazy callback testing is needed. Acked-by: Frederic Weisbecker Reviewed-by: Paul E. McKenney Tested-by: Paul E. McKenney Signed-off-by: Joel Fernandes

rcuscale: Ditch rcu_scale_shutdown in favor of torture_shutdown_init()

2026-03-30T19:48:13+00:00

The torture_shutdown_init() function spawns a shutdown kthread in a manner very similar to that implemented by rcu_scale_shutdown(). This commit therefore re-implements rcu_scale_shutdown() in terms of torture_shutdown_init(). This patch was generated by Claude given as input the patch making the same transformation of ref_scale_shutdown(). Signed-off-by: Paul E. McKenney Signed-off-by: Joel Fernandes

refscale: Ditch ref_scale_shutdown in favor of torture_shutdown_init()

2026-03-30T19:48:13+00:00

The torture_shutdown_init() function spawns a shutdown kthread in a manner very similar to that implemented by ref_scale_shutdown(). This commit therefore re-implements ref_scale_shutdown in terms of torture_shutdown_init(). The initial draft of this patch was generated by version 2.1.16 of the Claude AI/LLM, but trained and configured for use by my employer, and prompted to refer to Linux-kernel source code. This initial draft failed to provide a forward reference to ref_scale_cleanup(), passed zero to torture_shutdown_init() for an unwelcome insta-shutdown, and failed to pass the kvm.sh --duration argument in as a refscale module parameter. On the other hand, it did catch the need to NULL main_task on the post-test self-shutdown code path, which I might well have forgotten to do. This version of the patch fixes those problems, and in fact very little of the initial draft remains. Signed-off-by: Paul E. McKenney Signed-off-by: Joel Fernandes

rcutorture: Fix numeric "test" comparison in srcu_lockdep.sh

2026-03-30T19:48:13+00:00

This commit switches from "-eq" to "=" to handle the non-numeric comparisons in srcu_lockdep.sh. While in the area, adjust SRCU flavor to improve coverage. Signed-off-by: Paul E. McKenney Signed-off-by: Joel Fernandes

torture: Print informative message for test without recheck file

2026-03-30T19:48:13+00:00

If a type of torture test lacks a recheck file, a bash diagnostic is printed, which looks like a torture-test bug. This commit gets rid of this false positive by explicitly checking for the file, invoking it if it exists, otherwise printing an informative non-diagnostic message. Signed-off-by: Paul E. McKenney Signed-off-by: Joel Fernandes

torture: Make hangs more visible in torture.sh output

2026-03-30T19:48:13+00:00

This commit labels "QEMU killed" lines so that they will be picked up by torture.sh processing. Signed-off-by: Paul E. McKenney Signed-off-by: Joel Fernandes

kvm-check-branches.sh: Remove in favor of kvm-series.sh

2026-03-30T19:48:13+00:00

The kvm-series.sh script is an order-of-magnitude optimization of kvm-check-branches.sh, so remove the old script. Signed-off-by: Paul E. McKenney Signed-off-by: Joel Fernandes

rcutorture: Add a textbook-style trivial preemptible RCU

2026-03-30T19:48:13+00:00

This commit adds a trivial textbook implementation of preemptible RCU to rcutorture ("torture_type=trivial-preempt"), similar in spirit to the existing "torture_type=trivial" textbook implementation of non-preemptible RCU. Neither trivial RCU implementation has any value for production use, and are intended only to keep Paul honest in his introductory writings and presentations. [ paulmck: Apply kernel test robot feedback. ] Signed-off-by: Joel Fernandes

scftorture: Update due to x86 not supporting none/voluntary preemption

2026-03-05T21:11:10+00:00

As of v7.0-rc1, architectures that support preemption, including x86 and arm64, no longer support CONFIG_PREEMPT_NONE or CONFIG_PREEMPT_VOLUNTARY. Attempting to build kernels with these two Kconfig options results in .config errors. This commit therefore switches such scftorture scenarios to CONFIG_PREEMPT_LAZY. Signed-off-by: Paul E. McKenney Signed-off-by: Boqun Feng Link: https://patch.msgid.link/20260303235903.1967409-4-paulmck@kernel.org