linux-stable.git/kernel/trace/rv/monitors, branch linux-rolling-lts

rv: Make rtapp/pagefault monitor depends on CONFIG_MMU

2025-10-20T10:47:40+00:00

There is no page fault without MMU. Compiling the rtapp/pagefault monitor
without CONFIG_MMU fails as page fault tracepoints' definitions are not
available.

Make rtapp/pagefault monitor depends on CONFIG_MMU.

Fixes: 9162620eb604 ("rv: Add rtapp_pagefault monitor")
Signed-off-by: Nam Cao 
Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202509260455.6Z9Vkty4-lkp@intel.com/
Cc: stable@vger.kernel.org
Reviewed-by: Gabriele Monaco 
Link: https://lore.kernel.org/r/20251002082317.973839-1-namcao@linutronix.de
Signed-off-by: Gabriele Monaco

rv: Support systems with time64-only syscalls

2025-09-15T06:36:27+00:00

Some systems (like 32-bit RISC-V) only have the 64-bit time_t versions
of syscalls.  So handle the 32-bit time_t version of those being
undefined.

Fixes: f74f8bb246cf ("rv: Add rtapp_sleep monitor")
Closes: https://lore.kernel.org/oe-kbuild-all/202508160204.SsFyNfo6-lkp@intel.com
Signed-off-by: Palmer Dabbelt 
Acked-by: Nam Cao 
Link: https://lore.kernel.org/r/20250804194518.97620-2-palmer@dabbelt.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)

sched: Adapt sched tracepoints for RV task model

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

Add the following tracepoint:
* sched_set_need_resched(tsk, cpu, tif)
    Called when a task is set the need resched [lazy] flag

Remove the unused ip parameter from sched_entry and sched_exit and alter
sched_entry to have a value of preempt consistent with the one used in
sched_switch.

Also adapt all monitors using sched_{entry,exit} to avoid breaking build.

These tracepoints are useful to describe the Linux task model and are
adapted from the patches by Daniel Bristot de Oliveira
(https://bristot.me/linux-task-model/).

Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Masami Hiramatsu 
Cc: Nam Cao 
Cc: Tomas Glozar 
Cc: Juri Lelli 
Cc: Clark Williams 
Cc: John Kacur 
Link: https://lore.kernel.org/20250728135022.255578-7-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco 
Signed-off-by: Steven Rostedt (Google)

rv: Adjust monitor dependencies

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

RV monitors relying on the preemptirqs tracepoints are set as dependent
on PREEMPT_TRACER and IRQSOFF_TRACER. In fact, those configurations do
enable the tracepoints but are not the minimal configurations enabling
them, which are TRACE_PREEMPT_TOGGLE and TRACE_IRQFLAGS (not selectable
manually).

Set TRACE_PREEMPT_TOGGLE and TRACE_IRQFLAGS as dependencies for
monitors.

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/20250728135022.255578-5-gmonaco@redhat.com
Fixes: fbe6c09b7eb4 ("rv: Add scpd, snep and sncid per-cpu monitors")
Acked-by: Nam Cao 
Signed-off-by: Gabriele Monaco 
Signed-off-by: Steven Rostedt (Google)

rv: Return init error when registering monitors

2025-07-24T14:43:46+00:00

Monitors generated with dot2k have their registration function (the one
called during monitor initialisation) return always 0, even if the
registration failed on RV side.
This can hide potential errors.

Return the value returned by the RV register function.

Cc: Masami Hiramatsu 
Cc: Tomas Glozar 
Cc: Juri Lelli 
Cc: Clark Williams 
Cc: John Kacur 
Link: https://lore.kernel.org/20250723161240.194860-6-gmonaco@redhat.com
Reviewed-by: Nam Cao 
Signed-off-by: Gabriele Monaco 
Signed-off-by: Steven Rostedt (Google)

tools/dot2c: Fix generated files going over 100 column limit

2025-07-24T14:43:46+00:00

The dot2c.py script generates all states in a single line. This breaks the
100 column limit when the state machines are non-trivial.

Change dot2c.py to generate the states in separate lines in case the
generated line is going to be too long.

Also adapt existing monitors with line length over the limit.

Cc: Masami Hiramatsu 
Cc: Tomas Glozar 
Cc: Juri Lelli 
Cc: Clark Williams 
Cc: John Kacur 
Link: https://lore.kernel.org/20250723161240.194860-4-gmonaco@redhat.com
Suggested-by: Nam Cao 
Signed-off-by: Gabriele Monaco 
Signed-off-by: Steven Rostedt (Google)

rv: Allow to configure the number of per-task monitor

2025-07-09T19:27:02+00:00

Now that there are 2 monitors for real-time applications, users may want to
enable both of them simultaneously. Make the number of per-task monitor
configurable. Default it to 2 for now.

Cc: John Ogness 
Cc: Masami Hiramatsu 
Cc: Mathieu Desnoyers 
Link: https://lore.kernel.org/93e83313fc4ba7f6e66f4abe80ca5f5494d658d0.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco 
Signed-off-by: Nam Cao 
Signed-off-by: Steven Rostedt (Google)