From: Steven Rostedt <rostedt@kernel.org>
To: linux-kernel@vger.kernel.org
Cc: Tomas Glozar <tglozar@redhat.com>, John Kacur <jkacur@redhat.com>,
Ingo Molnar <mingo@redhat.com>, Jonathan Corbet <corbet@lwn.net>,
Masami Hiramatsu <mhiramat@kernel.org>,
Juri Lelli <jlelli@redhat.com>,
Clark Williams <williams@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Gabriele Monaco <gmonaco@redhat.com>,
Nam Cao <namcao@linutronix.de>
Subject: [for-next][PATCH 10/11] rv: Add nrp and sssw per-task monitors
Date: Mon, 28 Jul 2025 16:49:44 -0400 [thread overview]
Message-ID: <20250728204959.425356272@kernel.org> (raw)
In-Reply-To: 20250728204934.281385756@kernel.org
From: Gabriele Monaco <gmonaco@redhat.com>
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 <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20250728135022.255578-9-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Acked-by: Nam Cao <namcao@linutronix.de>
Tested-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
Documentation/trace/rv/monitor_sched.rst | 167 +++++++++++++++++++++
kernel/trace/rv/Kconfig | 2 +
kernel/trace/rv/Makefile | 2 +
kernel/trace/rv/monitors/nrp/Kconfig | 16 ++
kernel/trace/rv/monitors/nrp/nrp.c | 138 +++++++++++++++++
kernel/trace/rv/monitors/nrp/nrp.h | 75 +++++++++
kernel/trace/rv/monitors/nrp/nrp_trace.h | 15 ++
kernel/trace/rv/monitors/sched/Kconfig | 1 +
kernel/trace/rv/monitors/sssw/Kconfig | 15 ++
kernel/trace/rv/monitors/sssw/sssw.c | 116 ++++++++++++++
kernel/trace/rv/monitors/sssw/sssw.h | 105 +++++++++++++
kernel/trace/rv/monitors/sssw/sssw_trace.h | 15 ++
kernel/trace/rv/rv_trace.h | 2 +
tools/verification/models/sched/nrp.dot | 29 ++++
tools/verification/models/sched/sssw.dot | 30 ++++
15 files changed, 728 insertions(+)
create mode 100644 kernel/trace/rv/monitors/nrp/Kconfig
create mode 100644 kernel/trace/rv/monitors/nrp/nrp.c
create mode 100644 kernel/trace/rv/monitors/nrp/nrp.h
create mode 100644 kernel/trace/rv/monitors/nrp/nrp_trace.h
create mode 100644 kernel/trace/rv/monitors/sssw/Kconfig
create mode 100644 kernel/trace/rv/monitors/sssw/sssw.c
create mode 100644 kernel/trace/rv/monitors/sssw/sssw.h
create mode 100644 kernel/trace/rv/monitors/sssw/sssw_trace.h
create mode 100644 tools/verification/models/sched/nrp.dot
create mode 100644 tools/verification/models/sched/sssw.dot
diff --git a/Documentation/trace/rv/monitor_sched.rst b/Documentation/trace/rv/monitor_sched.rst
index 6c4c00216c07..11ef963cb578 100644
--- a/Documentation/trace/rv/monitor_sched.rst
+++ b/Documentation/trace/rv/monitor_sched.rst
@@ -174,6 +174,173 @@ running one, no real task switch occurs but interrupts are disabled nonetheless:
| | irq_entry
+---------------+ irq_enable
+Monitor nrp
+-----------
+
+The need resched preempts (nrp) monitor ensures preemption requires
+``need_resched``. Only kernel preemption is considered, since preemption
+while returning to userspace, for this monitor, is indistinguishable from
+``sched_switch_yield`` (described in the sssw monitor).
+A kernel preemption is whenever ``__schedule`` is called with the preemption
+flag set to true (e.g. from preempt_enable or exiting from interrupts). This
+type of preemption occurs after the need for ``rescheduling`` has been set.
+This is not valid for the *lazy* variant of the flag, which causes only
+userspace preemption.
+A ``schedule_entry_preempt`` may involve a task switch or not, in the latter
+case, a task goes through the scheduler from a preemption context but it is
+picked as the next task to run. Since the scheduler runs, this clears the need
+to reschedule. The ``any_thread_running`` state does not imply the monitored
+task is not running as this monitor does not track the outcome of scheduling.
+
+In theory, a preemption can only occur after the ``need_resched`` flag is set. In
+practice, however, it is possible to see a preemption where the flag is not
+set. This can happen in one specific condition::
+
+ need_resched
+ preempt_schedule()
+ preempt_schedule_irq()
+ __schedule()
+ !need_resched
+ __schedule()
+
+In the situation above, standard preemption starts (e.g. from preempt_enable
+when the flag is set), an interrupt occurs before scheduling and, on its exit
+path, it schedules, which clears the ``need_resched`` flag.
+When the preempted task runs again, the standard preemption started earlier
+resumes, although the flag is no longer set. The monitor considers this a
+``nested_preemption``, this allows another preemption without re-setting the
+flag. This condition relaxes the monitor constraints and may catch false
+negatives (i.e. no real ``nested_preemptions``) but makes the monitor more
+robust and able to validate other scenarios.
+For simplicity, the monitor starts in ``preempt_irq``, although no interrupt
+occurred, as the situation above is hard to pinpoint::
+
+ schedule_entry
+ irq_entry #===========================================#
+ +-------------------------- H H
+ | H H
+ +-------------------------> H any_thread_running H
+ H H
+ +-------------------------> H H
+ | #===========================================#
+ | schedule_entry | ^
+ | schedule_entry_preempt | sched_need_resched | schedule_entry
+ | | schedule_entry_preempt
+ | v |
+ | +----------------------+ |
+ | +--- | | |
+ | sched_need_resched | | rescheduling | -+
+ | +--> | |
+ | +----------------------+
+ | | irq_entry
+ | v
+ | +----------------------+
+ | | | ---+
+ | ---> | | | sched_need_resched
+ | | preempt_irq | | irq_entry
+ | | | <--+
+ | | | <--+
+ | +----------------------+ |
+ | | schedule_entry | sched_need_resched
+ | | schedule_entry_preempt |
+ | v |
+ | +-----------------------+ |
+ +-------------------------- | nested_preempt | --+
+ +-----------------------+
+ ^ irq_entry |
+ +-------------------+
+
+Due to how the ``need_resched`` flag on the preemption count works on arm64,
+this monitor is unstable on that architecture, as it often records preemption
+when the flag is not set, even in presence of the workaround above.
+For the time being, the monitor is disabled by default on arm64.
+
+Monitor sssw
+------------
+
+The set state sleep and wakeup (sssw) monitor ensures ``set_state`` to
+sleepable leads to sleeping and sleeping tasks require wakeup. It includes the
+following types of switch:
+
+* ``switch_suspend``:
+ a task puts itself to sleep, this can happen only after explicitly setting
+ the task to ``sleepable``. After a task is suspended, it needs to be woken up
+ (``waking`` state) before being switched in again.
+ Setting the task's state to ``sleepable`` can be reverted before switching if it
+ is woken up or set to ``runnable``.
+* ``switch_blocking``:
+ a special case of a ``switch_suspend`` where the task is waiting on a
+ sleeping RT lock (``PREEMPT_RT`` only), it is common to see wakeup and set
+ state events racing with each other and this leads the model to perceive this
+ type of switch when the task is not set to sleepable. This is a limitation of
+ the model in SMP system and workarounds may slow down the system.
+* ``switch_preempt``:
+ a task switch as a result of kernel preemption (``schedule_entry_preempt`` in
+ the nrp model).
+* ``switch_yield``:
+ a task explicitly calls the scheduler or is preempted while returning to
+ userspace. It can happen after a ``yield`` system call, from the idle task or
+ if the ``need_resched`` flag is set. By definition, a task cannot yield while
+ ``sleepable`` as that would be a suspension. A special case of a yield occurs
+ when a task in ``TASK_INTERRUPTIBLE`` calls the scheduler while a signal is
+ pending. The task doesn't go through the usual blocking/waking and is set
+ back to runnable, the resulting switch (if there) looks like a yield to the
+ ``signal_wakeup`` state and is followed by the signal delivery. From this
+ state, the monitor expects a signal even if it sees a wakeup event, although
+ not necessary, to rule out false negatives.
+
+This monitor doesn't include a running state, ``sleepable`` and ``runnable``
+are only referring to the task's desired state, which could be scheduled out
+(e.g. due to preemption). However, it does include the event
+``sched_switch_in`` to represent when a task is allowed to become running. This
+can be triggered also by preemption, but cannot occur after the task got to
+``sleeping`` before a ``wakeup`` occurs::
+
+ +--------------------------------------------------------------------------+
+ | |
+ | |
+ | switch_suspend | |
+ | switch_blocking | |
+ v v |
+ +----------+ #==========================# set_state_runnable |
+ | | H H wakeup |
+ | | H H switch_in |
+ | | H H switch_yield |
+ | sleeping | H H switch_preempt |
+ | | H H signal_deliver |
+ | | switch_ H H ------+ |
+ | | _blocking H runnable H | |
+ | | <----------- H H <-----+ |
+ +----------+ H H |
+ | wakeup H H |
+ +---------------------> H H |
+ H H |
+ +---------> H H |
+ | #==========================# |
+ | | ^ |
+ | | | set_state_runnable |
+ | | | wakeup |
+ | set_state_sleepable | +------------------------+
+ | v | |
+ | +--------------------------+ set_state_sleepable
+ | | | switch_in
+ | | | switch_preempt
+ signal_deliver | sleepable | signal_deliver
+ | | | ------+
+ | | | |
+ | | | <-----+
+ | +--------------------------+
+ | | ^
+ | switch_yield | set_state_sleepable
+ | v |
+ | +---------------+ |
+ +---------- | signal_wakeup | -+
+ +---------------+
+ ^ | switch_in
+ | | switch_preempt
+ | | switch_yield
+ +-----------+ wakeup
+
References
----------
diff --git a/kernel/trace/rv/Kconfig b/kernel/trace/rv/Kconfig
index b688b24081c8..59d0db898d4a 100644
--- a/kernel/trace/rv/Kconfig
+++ b/kernel/trace/rv/Kconfig
@@ -55,6 +55,8 @@ source "kernel/trace/rv/monitors/snroc/Kconfig"
source "kernel/trace/rv/monitors/scpd/Kconfig"
source "kernel/trace/rv/monitors/snep/Kconfig"
source "kernel/trace/rv/monitors/sts/Kconfig"
+source "kernel/trace/rv/monitors/nrp/Kconfig"
+source "kernel/trace/rv/monitors/sssw/Kconfig"
# Add new sched monitors here
source "kernel/trace/rv/monitors/rtapp/Kconfig"
diff --git a/kernel/trace/rv/Makefile b/kernel/trace/rv/Makefile
index 1939d3d7621c..2afac88539d3 100644
--- a/kernel/trace/rv/Makefile
+++ b/kernel/trace/rv/Makefile
@@ -14,6 +14,8 @@ obj-$(CONFIG_RV_MON_RTAPP) += monitors/rtapp/rtapp.o
obj-$(CONFIG_RV_MON_PAGEFAULT) += monitors/pagefault/pagefault.o
obj-$(CONFIG_RV_MON_SLEEP) += monitors/sleep/sleep.o
obj-$(CONFIG_RV_MON_STS) += monitors/sts/sts.o
+obj-$(CONFIG_RV_MON_NRP) += monitors/nrp/nrp.o
+obj-$(CONFIG_RV_MON_SSSW) += monitors/sssw/sssw.o
# Add new monitors here
obj-$(CONFIG_RV_REACTORS) += rv_reactors.o
obj-$(CONFIG_RV_REACT_PRINTK) += reactor_printk.o
diff --git a/kernel/trace/rv/monitors/nrp/Kconfig b/kernel/trace/rv/monitors/nrp/Kconfig
new file mode 100644
index 000000000000..f5ec08f65535
--- /dev/null
+++ b/kernel/trace/rv/monitors/nrp/Kconfig
@@ -0,0 +1,16 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+config RV_MON_NRP
+ depends on RV
+ depends on RV_MON_SCHED
+ default y if !ARM64
+ select DA_MON_EVENTS_ID
+ bool "nrp monitor"
+ help
+ Monitor to ensure preemption requires need resched.
+ This monitor is part of the sched monitors collection.
+
+ This monitor is unstable on arm64, say N unless you are testing it.
+
+ For further information, see:
+ Documentation/trace/rv/monitor_sched.rst
diff --git a/kernel/trace/rv/monitors/nrp/nrp.c b/kernel/trace/rv/monitors/nrp/nrp.c
new file mode 100644
index 000000000000..5a83b7171432
--- /dev/null
+++ b/kernel/trace/rv/monitors/nrp/nrp.c
@@ -0,0 +1,138 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/ftrace.h>
+#include <linux/tracepoint.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/rv.h>
+#include <rv/instrumentation.h>
+#include <rv/da_monitor.h>
+
+#define MODULE_NAME "nrp"
+
+#include <trace/events/irq.h>
+#include <trace/events/sched.h>
+#include <rv_trace.h>
+#include <monitors/sched/sched.h>
+
+#include "nrp.h"
+
+static struct rv_monitor rv_nrp;
+DECLARE_DA_MON_PER_TASK(nrp, unsigned char);
+
+#ifdef CONFIG_X86_LOCAL_APIC
+#include <asm/trace/irq_vectors.h>
+
+static void handle_vector_irq_entry(void *data, int vector)
+{
+ da_handle_event_nrp(current, irq_entry_nrp);
+}
+
+static void attach_vector_irq(void)
+{
+ rv_attach_trace_probe("nrp", local_timer_entry, handle_vector_irq_entry);
+ if (IS_ENABLED(CONFIG_IRQ_WORK))
+ rv_attach_trace_probe("nrp", irq_work_entry, handle_vector_irq_entry);
+ if (IS_ENABLED(CONFIG_SMP)) {
+ rv_attach_trace_probe("nrp", reschedule_entry, handle_vector_irq_entry);
+ rv_attach_trace_probe("nrp", call_function_entry, handle_vector_irq_entry);
+ rv_attach_trace_probe("nrp", call_function_single_entry, handle_vector_irq_entry);
+ }
+}
+
+static void detach_vector_irq(void)
+{
+ rv_detach_trace_probe("nrp", local_timer_entry, handle_vector_irq_entry);
+ if (IS_ENABLED(CONFIG_IRQ_WORK))
+ rv_detach_trace_probe("nrp", irq_work_entry, handle_vector_irq_entry);
+ if (IS_ENABLED(CONFIG_SMP)) {
+ rv_detach_trace_probe("nrp", reschedule_entry, handle_vector_irq_entry);
+ rv_detach_trace_probe("nrp", call_function_entry, handle_vector_irq_entry);
+ rv_detach_trace_probe("nrp", call_function_single_entry, handle_vector_irq_entry);
+ }
+}
+
+#else
+/* We assume irq_entry tracepoints are sufficient on other architectures */
+static void attach_vector_irq(void) { }
+static void detach_vector_irq(void) { }
+#endif
+
+static void handle_irq_entry(void *data, int irq, struct irqaction *action)
+{
+ da_handle_event_nrp(current, irq_entry_nrp);
+}
+
+static void handle_sched_need_resched(void *data, struct task_struct *tsk,
+ int cpu, int tif)
+{
+ /*
+ * Although need_resched leads to both the rescheduling and preempt_irq
+ * states, it is safer to start the monitor always in preempt_irq,
+ * which may not mirror the system state but makes the monitor simpler,
+ */
+ if (tif == TIF_NEED_RESCHED)
+ da_handle_start_event_nrp(tsk, sched_need_resched_nrp);
+}
+
+static void handle_schedule_entry(void *data, bool preempt)
+{
+ if (preempt)
+ da_handle_event_nrp(current, schedule_entry_preempt_nrp);
+ else
+ da_handle_event_nrp(current, schedule_entry_nrp);
+}
+
+static int enable_nrp(void)
+{
+ int retval;
+
+ retval = da_monitor_init_nrp();
+ if (retval)
+ return retval;
+
+ rv_attach_trace_probe("nrp", irq_handler_entry, handle_irq_entry);
+ rv_attach_trace_probe("nrp", sched_set_need_resched_tp, handle_sched_need_resched);
+ rv_attach_trace_probe("nrp", sched_entry_tp, handle_schedule_entry);
+ attach_vector_irq();
+
+ return 0;
+}
+
+static void disable_nrp(void)
+{
+ rv_nrp.enabled = 0;
+
+ rv_detach_trace_probe("nrp", irq_handler_entry, handle_irq_entry);
+ rv_detach_trace_probe("nrp", sched_set_need_resched_tp, handle_sched_need_resched);
+ rv_detach_trace_probe("nrp", sched_entry_tp, handle_schedule_entry);
+ detach_vector_irq();
+
+ da_monitor_destroy_nrp();
+}
+
+static struct rv_monitor rv_nrp = {
+ .name = "nrp",
+ .description = "need resched preempts.",
+ .enable = enable_nrp,
+ .disable = disable_nrp,
+ .reset = da_monitor_reset_all_nrp,
+ .enabled = 0,
+};
+
+static int __init register_nrp(void)
+{
+ return rv_register_monitor(&rv_nrp, &rv_sched);
+}
+
+static void __exit unregister_nrp(void)
+{
+ rv_unregister_monitor(&rv_nrp);
+}
+
+module_init(register_nrp);
+module_exit(unregister_nrp);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Gabriele Monaco <gmonaco@redhat.com>");
+MODULE_DESCRIPTION("nrp: need resched preempts.");
diff --git a/kernel/trace/rv/monitors/nrp/nrp.h b/kernel/trace/rv/monitors/nrp/nrp.h
new file mode 100644
index 000000000000..c9f12207cbf6
--- /dev/null
+++ b/kernel/trace/rv/monitors/nrp/nrp.h
@@ -0,0 +1,75 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Automatically generated C representation of nrp automaton
+ * For further information about this format, see kernel documentation:
+ * Documentation/trace/rv/deterministic_automata.rst
+ */
+
+enum states_nrp {
+ preempt_irq_nrp = 0,
+ any_thread_running_nrp,
+ nested_preempt_nrp,
+ rescheduling_nrp,
+ state_max_nrp
+};
+
+#define INVALID_STATE state_max_nrp
+
+enum events_nrp {
+ irq_entry_nrp = 0,
+ sched_need_resched_nrp,
+ schedule_entry_nrp,
+ schedule_entry_preempt_nrp,
+ event_max_nrp
+};
+
+struct automaton_nrp {
+ char *state_names[state_max_nrp];
+ char *event_names[event_max_nrp];
+ unsigned char function[state_max_nrp][event_max_nrp];
+ unsigned char initial_state;
+ bool final_states[state_max_nrp];
+};
+
+static const struct automaton_nrp automaton_nrp = {
+ .state_names = {
+ "preempt_irq",
+ "any_thread_running",
+ "nested_preempt",
+ "rescheduling"
+ },
+ .event_names = {
+ "irq_entry",
+ "sched_need_resched",
+ "schedule_entry",
+ "schedule_entry_preempt"
+ },
+ .function = {
+ {
+ preempt_irq_nrp,
+ preempt_irq_nrp,
+ nested_preempt_nrp,
+ nested_preempt_nrp
+ },
+ {
+ any_thread_running_nrp,
+ rescheduling_nrp,
+ any_thread_running_nrp,
+ INVALID_STATE
+ },
+ {
+ nested_preempt_nrp,
+ preempt_irq_nrp,
+ any_thread_running_nrp,
+ any_thread_running_nrp
+ },
+ {
+ preempt_irq_nrp,
+ rescheduling_nrp,
+ any_thread_running_nrp,
+ any_thread_running_nrp
+ },
+ },
+ .initial_state = preempt_irq_nrp,
+ .final_states = { 0, 1, 0, 0 },
+};
diff --git a/kernel/trace/rv/monitors/nrp/nrp_trace.h b/kernel/trace/rv/monitors/nrp/nrp_trace.h
new file mode 100644
index 000000000000..2e13497de3b6
--- /dev/null
+++ b/kernel/trace/rv/monitors/nrp/nrp_trace.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*
+ * Snippet to be included in rv_trace.h
+ */
+
+#ifdef CONFIG_RV_MON_NRP
+DEFINE_EVENT(event_da_monitor_id, event_nrp,
+ TP_PROTO(int id, char *state, char *event, char *next_state, bool final_state),
+ TP_ARGS(id, state, event, next_state, final_state));
+
+DEFINE_EVENT(error_da_monitor_id, error_nrp,
+ TP_PROTO(int id, char *state, char *event),
+ TP_ARGS(id, state, event));
+#endif /* CONFIG_RV_MON_NRP */
diff --git a/kernel/trace/rv/monitors/sched/Kconfig b/kernel/trace/rv/monitors/sched/Kconfig
index ae3eb410abd7..aa16456da864 100644
--- a/kernel/trace/rv/monitors/sched/Kconfig
+++ b/kernel/trace/rv/monitors/sched/Kconfig
@@ -2,6 +2,7 @@
#
config RV_MON_SCHED
depends on RV
+ depends on RV_PER_TASK_MONITORS >= 3
bool "sched monitor"
help
Collection of monitors to check the scheduler behaves according to specifications.
diff --git a/kernel/trace/rv/monitors/sssw/Kconfig b/kernel/trace/rv/monitors/sssw/Kconfig
new file mode 100644
index 000000000000..23b7eeb38bbf
--- /dev/null
+++ b/kernel/trace/rv/monitors/sssw/Kconfig
@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+config RV_MON_SSSW
+ depends on RV
+ depends on RV_MON_SCHED
+ default y
+ select DA_MON_EVENTS_ID
+ bool "sssw monitor"
+ help
+ Monitor to ensure sched_set_state to sleepable leads to sleeping and
+ sleeping tasks require wakeup.
+ This monitor is part of the sched monitors collection.
+
+ For further information, see:
+ Documentation/trace/rv/monitor_sched.rst
diff --git a/kernel/trace/rv/monitors/sssw/sssw.c b/kernel/trace/rv/monitors/sssw/sssw.c
new file mode 100644
index 000000000000..84b8d890d9d4
--- /dev/null
+++ b/kernel/trace/rv/monitors/sssw/sssw.c
@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/ftrace.h>
+#include <linux/tracepoint.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/rv.h>
+#include <rv/instrumentation.h>
+#include <rv/da_monitor.h>
+
+#define MODULE_NAME "sssw"
+
+#include <trace/events/sched.h>
+#include <trace/events/signal.h>
+#include <rv_trace.h>
+#include <monitors/sched/sched.h>
+
+#include "sssw.h"
+
+static struct rv_monitor rv_sssw;
+DECLARE_DA_MON_PER_TASK(sssw, unsigned char);
+
+static void handle_sched_set_state(void *data, struct task_struct *tsk, int state)
+{
+ if (state == TASK_RUNNING)
+ da_handle_start_event_sssw(tsk, sched_set_state_runnable_sssw);
+ else
+ da_handle_event_sssw(tsk, sched_set_state_sleepable_sssw);
+}
+
+static void handle_sched_switch(void *data, bool preempt,
+ struct task_struct *prev,
+ struct task_struct *next,
+ unsigned int prev_state)
+{
+ if (preempt)
+ da_handle_event_sssw(prev, sched_switch_preempt_sssw);
+ else if (prev_state == TASK_RUNNING)
+ da_handle_event_sssw(prev, sched_switch_yield_sssw);
+ else if (prev_state == TASK_RTLOCK_WAIT)
+ /* special case of sleeping task with racy conditions */
+ da_handle_event_sssw(prev, sched_switch_blocking_sssw);
+ else
+ da_handle_event_sssw(prev, sched_switch_suspend_sssw);
+ da_handle_event_sssw(next, sched_switch_in_sssw);
+}
+
+static void handle_sched_wakeup(void *data, struct task_struct *p)
+{
+ /*
+ * Wakeup can also lead to signal_wakeup although the system is
+ * actually runnable. The monitor can safely start with this event.
+ */
+ da_handle_start_event_sssw(p, sched_wakeup_sssw);
+}
+
+static void handle_signal_deliver(void *data, int sig,
+ struct kernel_siginfo *info,
+ struct k_sigaction *ka)
+{
+ da_handle_event_sssw(current, signal_deliver_sssw);
+}
+
+static int enable_sssw(void)
+{
+ int retval;
+
+ retval = da_monitor_init_sssw();
+ if (retval)
+ return retval;
+
+ rv_attach_trace_probe("sssw", sched_set_state_tp, handle_sched_set_state);
+ rv_attach_trace_probe("sssw", sched_switch, handle_sched_switch);
+ rv_attach_trace_probe("sssw", sched_wakeup, handle_sched_wakeup);
+ rv_attach_trace_probe("sssw", signal_deliver, handle_signal_deliver);
+
+ return 0;
+}
+
+static void disable_sssw(void)
+{
+ rv_sssw.enabled = 0;
+
+ rv_detach_trace_probe("sssw", sched_set_state_tp, handle_sched_set_state);
+ rv_detach_trace_probe("sssw", sched_switch, handle_sched_switch);
+ rv_detach_trace_probe("sssw", sched_wakeup, handle_sched_wakeup);
+ rv_detach_trace_probe("sssw", signal_deliver, handle_signal_deliver);
+
+ da_monitor_destroy_sssw();
+}
+
+static struct rv_monitor rv_sssw = {
+ .name = "sssw",
+ .description = "set state sleep and wakeup.",
+ .enable = enable_sssw,
+ .disable = disable_sssw,
+ .reset = da_monitor_reset_all_sssw,
+ .enabled = 0,
+};
+
+static int __init register_sssw(void)
+{
+ return rv_register_monitor(&rv_sssw, &rv_sched);
+}
+
+static void __exit unregister_sssw(void)
+{
+ rv_unregister_monitor(&rv_sssw);
+}
+
+module_init(register_sssw);
+module_exit(unregister_sssw);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Gabriele Monaco <gmonaco@redhat.com>");
+MODULE_DESCRIPTION("sssw: set state sleep and wakeup.");
diff --git a/kernel/trace/rv/monitors/sssw/sssw.h b/kernel/trace/rv/monitors/sssw/sssw.h
new file mode 100644
index 000000000000..243d54050c94
--- /dev/null
+++ b/kernel/trace/rv/monitors/sssw/sssw.h
@@ -0,0 +1,105 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Automatically generated C representation of sssw automaton
+ * For further information about this format, see kernel documentation:
+ * Documentation/trace/rv/deterministic_automata.rst
+ */
+
+enum states_sssw {
+ runnable_sssw = 0,
+ signal_wakeup_sssw,
+ sleepable_sssw,
+ sleeping_sssw,
+ state_max_sssw
+};
+
+#define INVALID_STATE state_max_sssw
+
+enum events_sssw {
+ sched_set_state_runnable_sssw = 0,
+ sched_set_state_sleepable_sssw,
+ sched_switch_blocking_sssw,
+ sched_switch_in_sssw,
+ sched_switch_preempt_sssw,
+ sched_switch_suspend_sssw,
+ sched_switch_yield_sssw,
+ sched_wakeup_sssw,
+ signal_deliver_sssw,
+ event_max_sssw
+};
+
+struct automaton_sssw {
+ char *state_names[state_max_sssw];
+ char *event_names[event_max_sssw];
+ unsigned char function[state_max_sssw][event_max_sssw];
+ unsigned char initial_state;
+ bool final_states[state_max_sssw];
+};
+
+static const struct automaton_sssw automaton_sssw = {
+ .state_names = {
+ "runnable",
+ "signal_wakeup",
+ "sleepable",
+ "sleeping"
+ },
+ .event_names = {
+ "sched_set_state_runnable",
+ "sched_set_state_sleepable",
+ "sched_switch_blocking",
+ "sched_switch_in",
+ "sched_switch_preempt",
+ "sched_switch_suspend",
+ "sched_switch_yield",
+ "sched_wakeup",
+ "signal_deliver"
+ },
+ .function = {
+ {
+ runnable_sssw,
+ sleepable_sssw,
+ sleeping_sssw,
+ runnable_sssw,
+ runnable_sssw,
+ INVALID_STATE,
+ runnable_sssw,
+ runnable_sssw,
+ runnable_sssw
+ },
+ {
+ INVALID_STATE,
+ sleepable_sssw,
+ INVALID_STATE,
+ signal_wakeup_sssw,
+ signal_wakeup_sssw,
+ INVALID_STATE,
+ signal_wakeup_sssw,
+ signal_wakeup_sssw,
+ runnable_sssw
+ },
+ {
+ runnable_sssw,
+ sleepable_sssw,
+ sleeping_sssw,
+ sleepable_sssw,
+ sleepable_sssw,
+ sleeping_sssw,
+ signal_wakeup_sssw,
+ runnable_sssw,
+ sleepable_sssw
+ },
+ {
+ INVALID_STATE,
+ INVALID_STATE,
+ INVALID_STATE,
+ INVALID_STATE,
+ INVALID_STATE,
+ INVALID_STATE,
+ INVALID_STATE,
+ runnable_sssw,
+ INVALID_STATE
+ },
+ },
+ .initial_state = runnable_sssw,
+ .final_states = { 1, 0, 0, 0 },
+};
diff --git a/kernel/trace/rv/monitors/sssw/sssw_trace.h b/kernel/trace/rv/monitors/sssw/sssw_trace.h
new file mode 100644
index 000000000000..6c03cfc6960b
--- /dev/null
+++ b/kernel/trace/rv/monitors/sssw/sssw_trace.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*
+ * Snippet to be included in rv_trace.h
+ */
+
+#ifdef CONFIG_RV_MON_SSSW
+DEFINE_EVENT(event_da_monitor_id, event_sssw,
+ TP_PROTO(int id, char *state, char *event, char *next_state, bool final_state),
+ TP_ARGS(id, state, event, next_state, final_state));
+
+DEFINE_EVENT(error_da_monitor_id, error_sssw,
+ TP_PROTO(int id, char *state, char *event),
+ TP_ARGS(id, state, event));
+#endif /* CONFIG_RV_MON_SSSW */
diff --git a/kernel/trace/rv/rv_trace.h b/kernel/trace/rv/rv_trace.h
index 97b2f7e07f27..e4e78d23b7b0 100644
--- a/kernel/trace/rv/rv_trace.h
+++ b/kernel/trace/rv/rv_trace.h
@@ -123,6 +123,8 @@ DECLARE_EVENT_CLASS(error_da_monitor_id,
#include <monitors/wwnr/wwnr_trace.h>
#include <monitors/snroc/snroc_trace.h>
+#include <monitors/nrp/nrp_trace.h>
+#include <monitors/sssw/sssw_trace.h>
// Add new monitors based on CONFIG_DA_MON_EVENTS_ID here
#endif /* CONFIG_DA_MON_EVENTS_ID */
diff --git a/tools/verification/models/sched/nrp.dot b/tools/verification/models/sched/nrp.dot
new file mode 100644
index 000000000000..77bb64669416
--- /dev/null
+++ b/tools/verification/models/sched/nrp.dot
@@ -0,0 +1,29 @@
+digraph state_automaton {
+ center = true;
+ size = "7,11";
+ {node [shape = doublecircle] "any_thread_running"};
+ {node [shape = circle] "any_thread_running"};
+ {node [shape = circle] "nested_preempt"};
+ {node [shape = plaintext, style=invis, label=""] "__init_preempt_irq"};
+ {node [shape = circle] "preempt_irq"};
+ {node [shape = circle] "rescheduling"};
+ "__init_preempt_irq" -> "preempt_irq";
+ "any_thread_running" [label = "any_thread_running", color = green3];
+ "any_thread_running" -> "any_thread_running" [ label = "schedule_entry\nirq_entry" ];
+ "any_thread_running" -> "rescheduling" [ label = "sched_need_resched" ];
+ "nested_preempt" [label = "nested_preempt"];
+ "nested_preempt" -> "any_thread_running" [ label = "schedule_entry_preempt\nschedule_entry" ];
+ "nested_preempt" -> "nested_preempt" [ label = "irq_entry" ];
+ "nested_preempt" -> "preempt_irq" [ label = "sched_need_resched" ];
+ "preempt_irq" [label = "preempt_irq"];
+ "preempt_irq" -> "nested_preempt" [ label = "schedule_entry_preempt\nschedule_entry" ];
+ "preempt_irq" -> "preempt_irq" [ label = "irq_entry\nsched_need_resched" ];
+ "rescheduling" [label = "rescheduling"];
+ "rescheduling" -> "any_thread_running" [ label = "schedule_entry_preempt\nschedule_entry" ];
+ "rescheduling" -> "preempt_irq" [ label = "irq_entry" ];
+ "rescheduling" -> "rescheduling" [ label = "sched_need_resched" ];
+ { rank = min ;
+ "__init_preempt_irq";
+ "preempt_irq";
+ }
+}
diff --git a/tools/verification/models/sched/sssw.dot b/tools/verification/models/sched/sssw.dot
new file mode 100644
index 000000000000..4994c3e876be
--- /dev/null
+++ b/tools/verification/models/sched/sssw.dot
@@ -0,0 +1,30 @@
+digraph state_automaton {
+ center = true;
+ size = "7,11";
+ {node [shape = plaintext, style=invis, label=""] "__init_runnable"};
+ {node [shape = doublecircle] "runnable"};
+ {node [shape = circle] "runnable"};
+ {node [shape = circle] "signal_wakeup"};
+ {node [shape = circle] "sleepable"};
+ {node [shape = circle] "sleeping"};
+ "__init_runnable" -> "runnable";
+ "runnable" [label = "runnable", color = green3];
+ "runnable" -> "runnable" [ label = "sched_set_state_runnable\nsched_wakeup\nsched_switch_in\nsched_switch_yield\nsched_switch_preempt\nsignal_deliver" ];
+ "runnable" -> "sleepable" [ label = "sched_set_state_sleepable" ];
+ "runnable" -> "sleeping" [ label = "sched_switch_blocking" ];
+ "signal_wakeup" [label = "signal_wakeup"];
+ "signal_wakeup" -> "runnable" [ label = "signal_deliver" ];
+ "signal_wakeup" -> "signal_wakeup" [ label = "sched_switch_in\nsched_switch_preempt\nsched_switch_yield\nsched_wakeup" ];
+ "signal_wakeup" -> "sleepable" [ label = "sched_set_state_sleepable" ];
+ "sleepable" [label = "sleepable"];
+ "sleepable" -> "runnable" [ label = "sched_set_state_runnable\nsched_wakeup" ];
+ "sleepable" -> "signal_wakeup" [ label = "sched_switch_yield" ];
+ "sleepable" -> "sleepable" [ label = "sched_set_state_sleepable\nsched_switch_in\nsched_switch_preempt\nsignal_deliver" ];
+ "sleepable" -> "sleeping" [ label = "sched_switch_suspend\nsched_switch_blocking" ];
+ "sleeping" [label = "sleeping"];
+ "sleeping" -> "runnable" [ label = "sched_wakeup" ];
+ { rank = min ;
+ "__init_runnable";
+ "runnable";
+ }
+}
--
2.47.2
next prev parent reply other threads:[~2025-07-28 20:49 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-28 20:49 [for-next][PATCH 00/11] verification: Updates for v6.17 Steven Rostedt
2025-07-28 20:49 ` [for-next][PATCH 01/11] rv: Fix wrong type cast in monitors_show() Steven Rostedt
2025-07-28 20:49 ` [for-next][PATCH 02/11] rv: Fix wrong type cast in reactors_show() and monitor_reactor_show() Steven Rostedt
2025-07-28 20:49 ` [for-next][PATCH 03/11] rv: Add da_handle_start_run_event_ to per-task monitors Steven Rostedt
2025-07-28 20:49 ` [for-next][PATCH 04/11] rv: Remove trailing whitespace from tracepoint string Steven Rostedt
2025-07-28 20:49 ` [for-next][PATCH 05/11] rv: Use strings in da monitors tracepoints Steven Rostedt
2025-07-28 20:49 ` [for-next][PATCH 06/11] rv: Adjust monitor dependencies Steven Rostedt
2025-07-28 20:49 ` [for-next][PATCH 07/11] rv: Retry when da monitor detects race conditions Steven Rostedt
2025-07-28 20:49 ` [for-next][PATCH 08/11] sched: Adapt sched tracepoints for RV task model Steven Rostedt
2025-07-28 20:49 ` [for-next][PATCH 09/11] rv: Replace tss and sncid monitors with more complete sts Steven Rostedt
2025-07-28 20:49 ` Steven Rostedt [this message]
2025-07-28 20:49 ` [for-next][PATCH 11/11] rv: Add opid per-cpu monitor Steven Rostedt
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