linux-toradex.git/kernel/trace/rv/Kconfig, branch master

rv: Add KUnit mock for current

2026-07-31T14:27:45+00:00

Some monitors do not only rely on tracepoint arguments but also on the
currently executing task.
This makes it more challenging to mock events in KUnit.

Define wrapper functions around current, the functionality is mocked
only during KUnit, an additional function call is avoided using a static
branch unless any (even unrelated) KUnit test is running.

Rely on a global mock_current variable that is set only by the RV KUnit
tests and cleared on teardown. Unrelated KUnit tests that happen to
trigger RV handlers would see it null and use current.

Reviewed-by: Nam Cao 
Reviewed-by: Wen Yang 
Link: https://lore.kernel.org/r/20260723074534.43521-14-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco

rv: Add KUnit tests for some DA/HA monitors

2026-07-31T14:27:45+00:00

Validate the functionality of DA monitors by injecting events in a
controlled environment (KUnit) and expecting reactions.

Events handlers are exported directly from the monitor source files
without using system events and with dummy arguments (e.g. no real
tasks). If the provided sequence of events incurs a violation, the test
expects the stub version of rv_react() to be called.

This testing method can validate the entire monitor implementation since
it sits between the monitor and the system (in place of the
tracepoints). All sorts of system and timing events can be emulated
without affecting the running kernel.

Handlers and monitor functions are exported as part of a struct to
simplify the process of running KUnit tests from kernel modules.

Reviewed-by: Nam Cao 
Link: https://lore.kernel.org/r/20260723074534.43521-13-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco

rv/rtapp: Add wakeup monitor

2026-07-24T07:01:10+00:00

Add a wakeup monitor to detect a lower-priority task waking up a
higher-priority task.

The rtapp/sleep monitor already detects this. However, that monitor
triggers an error in the context of the wakee task and user only gets
the stacktrace of that task. It is also extremely useful to get the
stacktrace of the waker task, which this monitor offers. In other
words, this monitor complements the rtapp/sleep monitor.

Signed-off-by: Nam Cao 
Reviewed-by: Gabriele Monaco 
Link: https://lore.kernel.org/r/ba5658fa13e49ada466b84a2c211f233037180b5.1781852967.git.namcao@linutronix.de
Signed-off-by: Gabriele Monaco

rv: Add nomiss deadline monitor

2026-03-31T14:47:18+00:00

Add the deadline monitors collection to validate the deadline scheduler,
both for deadline tasks and servers.

The currently implemented monitors are:
* nomiss:
    validate dl entities run to completion before their deadiline

Reviewed-by: Nam Cao 
Reviewed-by: Juri Lelli 
Link: https://lore.kernel.org/r/20260330111010.153663-13-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco

rv: Add sample hybrid monitor stall

2026-03-31T14:47:17+00:00

Add a sample monitor to showcase hybrid/timed automata.
The stall monitor identifies tasks stalled for longer than a threshold
and reacts when that happens.

Reviewed-by: Nam Cao 
Link: https://lore.kernel.org/r/20260330111010.153663-7-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco

rv: Add Hybrid Automata monitor type

2026-03-31T14:47:16+00:00

Deterministic automata define which events are allowed in every state,
but cannot define more sophisticated constraint taking into account the
system's environment (e.g. time or other states not producing events).

Add the Hybrid Automata monitor type as an extension of Deterministic
automata where each state transition is validating a constraint on a
finite number of environment variables.
Hybrid automata can be used to implement timed automata, where the
environment variables are clocks.

Also implement the necessary functionality to handle clock constraints
(ns or jiffy granularity) on state and events.

Reviewed-by: Nam Cao 
Link: https://lore.kernel.org/r/20260330111010.153663-3-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco

rv: Add opid per-cpu monitor

2025-07-28T20:47:35+00:00

Add a per-cpu monitor as part of the sched model:
* opid: operations with preemption and irq disabled
    Monitor to ensure wakeup and need_resched occur with irq and
    preemption disabled or in irq handlers.

Cc: Jonathan Corbet 
Cc: Masami Hiramatsu 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Tomas Glozar 
Cc: Juri Lelli 
Cc: Clark Williams 
Cc: John Kacur 
Link: https://lore.kernel.org/20250728135022.255578-10-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco 
Acked-by: Nam Cao 
Tested-by: Nam Cao 
Signed-off-by: Steven Rostedt (Google)

rv: Add nrp and sssw per-task monitors

2025-07-28T20:47:34+00:00

Add 2 per-task monitors as part of the sched model:

* nrp: need-resched preempts
    Monitor to ensure preemption requires need resched.
* sssw: set state sleep and wakeup
    Monitor to ensure sched_set_state to sleepable leads to sleeping and
    sleeping tasks require wakeup.

Cc: Ingo Molnar 
Cc: Jonathan Corbet 
Cc: Masami Hiramatsu 
Cc: Tomas Glozar 
Cc: Juri Lelli 
Cc: Clark Williams 
Cc: John Kacur 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/20250728135022.255578-9-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco 
Acked-by: Nam Cao 
Tested-by: Nam Cao 
Signed-off-by: Steven Rostedt (Google)

rv: Replace tss and sncid monitors with more complete sts

2025-07-28T20:47:34+00:00

The tss monitor currently guarantees task switches can happen only while
scheduling, whereas the sncid monitor enforces scheduling occurs with
interrupt disabled.

Replace the monitors with a more comprehensive specification which
implies both but also ensures that:
* each scheduler call disable interrupts to switch
* each task switch happens with interrupts disabled

Cc: Ingo Molnar 
Cc: Jonathan Corbet 
Cc: Masami Hiramatsu 
Cc: Nam Cao 
Cc: Tomas Glozar 
Cc: Juri Lelli 
Cc: Clark Williams 
Cc: John Kacur 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/20250728135022.255578-8-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco 
Signed-off-by: Steven Rostedt (Google)

rv: Retry when da monitor detects race conditions

2025-07-28T20:47:34+00:00

DA monitor can be accessed from multiple cores simultaneously, this is
likely, for instance when dealing with per-task monitors reacting on
events that do not always occur on the CPU where the task is running.
This can cause race conditions where two events change the next state
and we see inconsistent values. E.g.:

  [62] event_srs: 27: sleepable x sched_wakeup -> running (final)
  [63] event_srs: 27: sleepable x sched_set_state_sleepable -> sleepable
  [63] error_srs: 27: event sched_switch_suspend not expected in the state running

In this case the monitor fails because the event on CPU 62 wins against
the one on CPU 63, although the correct state should have been
sleepable, since the task get suspended.

Detect if the current state was modified by using try_cmpxchg while
storing the next value. If it was, try again reading the current state.
After a maximum number of failed retries, react by calling a special
tracepoint, print on the console and reset the monitor.

Remove the functions da_monitor_curr_state() and da_monitor_set_state()
as they only hide the underlying implementation in this case.

Monitors where this type of condition can occur must be able to account
for racing events in any possible order, as we cannot know the winner.

Cc: Ingo Molnar 
Cc: Masami Hiramatsu 
Cc: Tomas Glozar 
Cc: Juri Lelli 
Cc: Clark Williams 
Cc: John Kacur 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/20250728135022.255578-6-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco 
Reviewed-by: Nam Cao 
Signed-off-by: Steven Rostedt (Google)