Re: [RFC PATCH v2 17/20] rcutorture: Add a test config to torture test low RCU_DYNTICKS width
From: "Paul E. McKenney" <paulmck@kernel.org>
Date: 2023-07-20 19:53:11
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On Thu, Jul 20, 2023 at 05:30:53PM +0100, Valentin Schneider wrote:
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We now have an RCU_EXPORT knob for configuring the size of the dynticks counter: CONFIG_RCU_DYNTICKS_BITS. Add a torture config for a ridiculously small counter (2 bits). This is ac opy of TREE4 with the added counter size restriction. Link: http://lore.kernel.org/r/4c2cb573-168f-4806-b1d9-164e8276e66a@paulmck-laptop (local) Suggested-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Valentin Schneider <vschneid@redhat.com> --- .../selftests/rcutorture/configs/rcu/TREE11 | 19 +++++++++++++++++++ .../rcutorture/configs/rcu/TREE11.boot | 1 + 2 files changed, 20 insertions(+) create mode 100644 tools/testing/selftests/rcutorture/configs/rcu/TREE11 create mode 100644 tools/testing/selftests/rcutorture/configs/rcu/TREE11.bootdiff --git a/tools/testing/selftests/rcutorture/configs/rcu/TREE11 b/tools/testing/selftests/rcutorture/configs/rcu/TREE11 new file mode 100644 index 0000000000000..aa7274efd9819 --- /dev/null +++ b/tools/testing/selftests/rcutorture/configs/rcu/TREE11@@ -0,0 +1,19 @@ +CONFIG_SMP=y +CONFIG_NR_CPUS=8 +CONFIG_PREEMPT_NONE=n +CONFIG_PREEMPT_VOLUNTARY=y +CONFIG_PREEMPT=n +CONFIG_PREEMPT_DYNAMIC=n +#CHECK#CONFIG_TREE_RCU=y +CONFIG_HZ_PERIODIC=n +CONFIG_NO_HZ_IDLE=n +CONFIG_NO_HZ_FULL=y +CONFIG_RCU_TRACE=y +CONFIG_RCU_FANOUT=4 +CONFIG_RCU_FANOUT_LEAF=3 +CONFIG_DEBUG_LOCK_ALLOC=n +CONFIG_DEBUG_OBJECTS_RCU_HEAD=n +CONFIG_RCU_EXPERT=y +CONFIG_RCU_EQS_DEBUG=y +CONFIG_RCU_LAZY=y +CONFIG_RCU_DYNTICKS_BITS=2
Why not just add this last line to the existing TREE04 scenario? That would ensure that it gets tested regularly without extending the time required to run a full set of rcutorture tests.
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diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TREE11.boot b/tools/testing/selftests/rcutorture/configs/rcu/TREE11.boot new file mode 100644 index 0000000000000..a8d94caf7d2fd --- /dev/null +++ b/tools/testing/selftests/rcutorture/configs/rcu/TREE11.boot@@ -0,0 +1 @@ +rcutree.rcu_fanout_leaf=4 nohz_full=1-N-- 2.31.1