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Message-ID: <06d48208-686a-4d33-95ca-4e4d5991a42f@redhat.com>
Date: Fri, 16 May 2025 16:31:03 +0000 (UTC)
From: Gabriele Monaco <gmonaco@...hat.com>
To: Nam Cao <namcao@...utronix.de>, Steven Rostedt <rostedt@...dmis.org>
Cc: linux-trace-kernel@...r.kernel.org, linux-kernel@...r.kernel.org,
	john.ogness@...utronix.de
Subject: Re: [PATCH v8 20/22] rv: Add rtapp_sleep monitor

2025-05-12T10:56:30Z Nam Cao <namcao@...utronix.de>:

> Add a monitor for checking that real-time tasks do not go to sleep in a
> manner that may cause undesirable latency.
>
> Also change
>     RV depends on TRACING
> to
>     RV select TRACING
> to avoid the following recursive dependency:
>
> error: recursive dependency detected!
>     symbol TRACING is selected by PREEMPTIRQ_TRACEPOINTS
>     symbol PREEMPTIRQ_TRACEPOINTS depends on TRACE_IRQFLAGS
>     symbol TRACE_IRQFLAGS is selected by RV_MON_SLEEP
>     symbol RV_MON_SLEEP depends on RV
>     symbol RV depends on TRACING
>
> Reviewed-by: Gabriele Monaco <gmonaco@...hat.com>
> Signed-off-by: Nam Cao <namcao@...utronix.de>
> ---
> kernel/trace/rv/Kconfig                      |   3 +-
> kernel/trace/rv/Makefile                     |   1 +
> kernel/trace/rv/monitors/sleep/Kconfig       |  13 +
> kernel/trace/rv/monitors/sleep/sleep.c       | 236 +++++++++++++++++
> kernel/trace/rv/monitors/sleep/sleep.h       | 250 +++++++++++++++++++
> kernel/trace/rv/monitors/sleep/sleep_trace.h |  14 ++
> kernel/trace/rv/rv_trace.h                   |   1 +
> tools/verification/models/rtapp/sleep.ltl    |  22 ++
> 8 files changed, 539 insertions(+), 1 deletion(-)
> create mode 100644 kernel/trace/rv/monitors/sleep/Kconfig
> create mode 100644 kernel/trace/rv/monitors/sleep/sleep.c
> create mode 100644 kernel/trace/rv/monitors/sleep/sleep.h
> create mode 100644 kernel/trace/rv/monitors/sleep/sleep_trace.h
> create mode 100644 tools/verification/models/rtapp/sleep.ltl
> [...]
> diff --git a/kernel/trace/rv/monitors/sleep/Kconfig b/kernel/trace/rv/monitors/sleep/Kconfig
> new file mode 100644
> index 000000000000..d00aa1aae069
> --- /dev/null
> +++ b/kernel/trace/rv/monitors/sleep/Kconfig
> @@ -0,0 +1,13 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +#
> +config RV_MON_SLEEP
> +   depends on RV
> +   select RV_LTL_MONITOR
> +   depends on HAVE_SYSCALL_TRACEPOINTS
> +   depends on RV_MON_RTAPP
> +   select TRACE_IRQFLAGS

I had a different approach towards those (the preemptirq tracepoints) under the assumption adding them introduces latency.
Besides me picking the wrong config (I used IRQSOFF, I'll fix that) I considered the monitor should /depend/ on the tracepoint instead of select it.
This way it looks easier to me to avoid making a change that introduces latency slip in when distribution maintainers enable the monitor (e.g. TRACE_IRQFLAGS may be enabled on debug kernels and using depends would automatically prevent the monitor on non-debug kernels).

Now is this concern justified? Is it only a performance issue for the preempt tracepoint or not even there?
I'd like to keep consistency but I really can't decide on which approach is better.

Also curiosity on my side (I didn't try), you require TRACE_IRQFLAGS to use hardirq_context but how different is it from in_hardirq() in your case?

Thanks,
Gabriele

> +   default y
> +   select LTL_MON_EVENTS_ID
> +   bool "sleep monitor"
> +   help
> +     Monitor that real-time tasks do not sleep in a manner that may cause undesirable latency.
> diff --git a/kernel/trace/rv/monitors/sleep/sleep.c b/kernel/trace/rv/monitors/sleep/sleep.c
> new file mode 100644
> index 000000000000..1841875e1cef
> --- /dev/null
> +++ b/kernel/trace/rv/monitors/sleep/sleep.c
> @@ -0,0 +1,236 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#include <linux/ftrace.h>
> +#include <linux/tracepoint.h>
> +#include <linux/init.h>
> +#include <linux/irqflags.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/rv.h>
> +#include <linux/sched/deadline.h>
> +#include <linux/sched/rt.h>
> +#include <rv/instrumentation.h>
> +
> +#define MODULE_NAME "sleep"
> +
> +#include <trace/events/syscalls.h>
> +#include <trace/events/sched.h>
> +#include <trace/events/lock.h>
> +#include <uapi/linux/futex.h>
> +#include <rv_trace.h>
> +#include <monitors/rtapp/rtapp.h>
> +
> +#include "sleep.h"
> +#include <rv/ltl_monitor.h>
> +
> +static void ltl_atoms_fetch(struct task_struct *task, struct ltl_monitor *mon)
> +{
> +   /*
> +    * This includes "actual" real-time tasks and also PI-boosted tasks. A task being PI-boosted
> +    * means it is blocking an "actual" real-task, therefore it should also obey the monitor's
> +    * rule, otherwise the "actual" real-task may be delayed.
> +    */
> +   ltl_atom_set(mon, LTL_RT, rt_or_dl_task(task));
> +}
> +
> +static void ltl_atoms_init(struct task_struct *task, struct ltl_monitor *mon, bool task_creation)
> +{
> +   ltl_atom_set(mon, LTL_SLEEP, false);
> +   ltl_atom_set(mon, LTL_WAKE, false);
> +   ltl_atom_set(mon, LTL_ABORT_SLEEP, false);
> +   ltl_atom_set(mon, LTL_WOKEN_BY_HARDIRQ, false);
> +   ltl_atom_set(mon, LTL_WOKEN_BY_NMI, false);
> +   ltl_atom_set(mon, LTL_WOKEN_BY_EQUAL_OR_HIGHER_PRIO, false);
> +
> +   if (task_creation) {
> +       ltl_atom_set(mon, LTL_KTHREAD_SHOULD_STOP, false);
> +       ltl_atom_set(mon, LTL_NANOSLEEP_CLOCK_MONOTONIC, false);
> +       ltl_atom_set(mon, LTL_NANOSLEEP_CLOCK_TAI, false);
> +       ltl_atom_set(mon, LTL_NANOSLEEP_TIMER_ABSTIME, false);
> +       ltl_atom_set(mon, LTL_CLOCK_NANOSLEEP, false);
> +       ltl_atom_set(mon, LTL_FUTEX_WAIT, false);
> +       ltl_atom_set(mon, LTL_FUTEX_LOCK_PI, false);
> +       ltl_atom_set(mon, LTL_BLOCK_ON_RT_MUTEX, false);
> +   }
> +
> +   if (task->flags & PF_KTHREAD) {
> +       ltl_atom_set(mon, LTL_KERNEL_THREAD, true);
> +
> +       /* kernel tasks do not do syscall */
> +       ltl_atom_set(mon, LTL_FUTEX_WAIT, false);
> +       ltl_atom_set(mon, LTL_FUTEX_LOCK_PI, false);
> +       ltl_atom_set(mon, LTL_NANOSLEEP_CLOCK_MONOTONIC, false);
> +       ltl_atom_set(mon, LTL_NANOSLEEP_CLOCK_TAI, false);
> +       ltl_atom_set(mon, LTL_NANOSLEEP_TIMER_ABSTIME, false);
> +       ltl_atom_set(mon, LTL_CLOCK_NANOSLEEP, false);
> +
> +       if (strstarts(task->comm, "migration/"))
> +           ltl_atom_set(mon, LTL_TASK_IS_MIGRATION, true);
> +       else
> +           ltl_atom_set(mon, LTL_TASK_IS_MIGRATION, false);
> +
> +       if (strstarts(task->comm, "rcu"))
> +           ltl_atom_set(mon, LTL_TASK_IS_RCU, true);
> +       else
> +           ltl_atom_set(mon, LTL_TASK_IS_RCU, false);
> +   } else {
> +       ltl_atom_set(mon, LTL_KTHREAD_SHOULD_STOP, false);
> +       ltl_atom_set(mon, LTL_KERNEL_THREAD, false);
> +       ltl_atom_set(mon, LTL_TASK_IS_RCU, false);
> +       ltl_atom_set(mon, LTL_TASK_IS_MIGRATION, false);
> +   }
> +
> +}
> +
> +static void handle_sched_set_state(void *data, struct task_struct *task, int state)
> +{
> +   if (state & TASK_INTERRUPTIBLE)
> +       ltl_atom_pulse(task, LTL_SLEEP, true);
> +   else if (state == TASK_RUNNING)
> +       ltl_atom_pulse(task, LTL_ABORT_SLEEP, true);
> +}
> +
> +static void handle_sched_wakeup(void *data, struct task_struct *task)
> +{
> +   ltl_atom_pulse(task, LTL_WAKE, true);
> +}
> +
> +static void handle_sched_waking(void *data, struct task_struct *task)
> +{
> +   if (this_cpu_read(hardirq_context)) {
> +       ltl_atom_pulse(task, LTL_WOKEN_BY_HARDIRQ, true);
> +   } else if (in_task()) {
> +       if (current->prio <= task->prio)
> +           ltl_atom_pulse(task, LTL_WOKEN_BY_EQUAL_OR_HIGHER_PRIO, true);
> +   } else if (in_nmi()) {
> +       ltl_atom_pulse(task, LTL_WOKEN_BY_NMI, true);
> +   }
> +}
> +
> +static void handle_contention_begin(void *data, void *lock, unsigned int flags)
> +{
> +   if (flags & LCB_F_RT)
> +       ltl_atom_update(current, LTL_BLOCK_ON_RT_MUTEX, true);
> +}
> +
> +static void handle_contention_end(void *data, void *lock, int ret)
> +{
> +   ltl_atom_update(current, LTL_BLOCK_ON_RT_MUTEX, false);
> +}
> +
> +static void handle_sys_enter(void *data, struct pt_regs *regs, long id)
> +{
> +   struct ltl_monitor *mon;
> +   unsigned long args[6];
> +   int op, cmd;
> +
> +   mon = ltl_get_monitor(current);
> +
> +   switch (id) {
> +   case __NR_clock_nanosleep:
> +#ifdef __NR_clock_nanosleep_time64
> +   case __NR_clock_nanosleep_time64:
> +#endif
> +       syscall_get_arguments(current, regs, args);
> +       ltl_atom_set(mon, LTL_NANOSLEEP_CLOCK_MONOTONIC, args[0] == CLOCK_MONOTONIC);
> +       ltl_atom_set(mon, LTL_NANOSLEEP_CLOCK_TAI, args[0] == CLOCK_TAI);
> +       ltl_atom_set(mon, LTL_NANOSLEEP_TIMER_ABSTIME, args[1] == TIMER_ABSTIME);
> +       ltl_atom_update(current, LTL_CLOCK_NANOSLEEP, true);
> +       break;
> +
> +   case __NR_futex:
> +#ifdef __NR_futex_time64
> +   case __NR_futex_time64:
> +#endif
> +       syscall_get_arguments(current, regs, args);
> +       op = args[1];
> +       cmd = op & FUTEX_CMD_MASK;
> +
> +       switch (cmd) {
> +       case FUTEX_LOCK_PI:
> +       case FUTEX_LOCK_PI2:
> +           ltl_atom_update(current, LTL_FUTEX_LOCK_PI, true);
> +           break;
> +       case FUTEX_WAIT:
> +       case FUTEX_WAIT_BITSET:
> +       case FUTEX_WAIT_REQUEUE_PI:
> +           ltl_atom_update(current, LTL_FUTEX_WAIT, true);
> +           break;
> +       }
> +       break;
> +   }
> +}
> +
> +static void handle_sys_exit(void *data, struct pt_regs *regs, long ret)
> +{
> +   struct ltl_monitor *mon = ltl_get_monitor(current);
> +
> +   ltl_atom_set(mon, LTL_FUTEX_LOCK_PI, false);
> +   ltl_atom_set(mon, LTL_FUTEX_WAIT, false);
> +   ltl_atom_set(mon, LTL_NANOSLEEP_CLOCK_MONOTONIC, false);
> +   ltl_atom_set(mon, LTL_NANOSLEEP_CLOCK_TAI, false);
> +   ltl_atom_set(mon, LTL_NANOSLEEP_TIMER_ABSTIME, false);
> +   ltl_atom_update(current, LTL_CLOCK_NANOSLEEP, false);
> +}
> +
> +static void handle_kthread_stop(void *data, struct task_struct *task)
> +{
> +   /* FIXME: this could race with other tracepoint handlers */
> +   ltl_atom_update(task, LTL_KTHREAD_SHOULD_STOP, true);
> +}
> +
> +static int enable_sleep(void)
> +{
> +   int retval;
> +
> +   retval = ltl_monitor_init();
> +   if (retval)
> +       return retval;
> +
> +   rv_attach_trace_probe("rtapp_sleep", sched_waking, handle_sched_waking);
> +   rv_attach_trace_probe("rtapp_sleep", sched_wakeup, handle_sched_wakeup);
> +   rv_attach_trace_probe("rtapp_sleep", sched_set_state_tp, handle_sched_set_state);
> +   rv_attach_trace_probe("rtapp_sleep", contention_begin, handle_contention_begin);
> +   rv_attach_trace_probe("rtapp_sleep", contention_end, handle_contention_end);
> +   rv_attach_trace_probe("rtapp_sleep", sched_kthread_stop, handle_kthread_stop);
> +   rv_attach_trace_probe("rtapp_sleep", sys_enter, handle_sys_enter);
> +   rv_attach_trace_probe("rtapp_sleep", sys_exit, handle_sys_exit);
> +   return 0;
> +}
> +
> +static void disable_sleep(void)
> +{
> +   rv_detach_trace_probe("rtapp_sleep", sched_waking, handle_sched_waking);
> +   rv_detach_trace_probe("rtapp_sleep", sched_wakeup, handle_sched_wakeup);
> +   rv_detach_trace_probe("rtapp_sleep", sched_set_state_tp, handle_sched_set_state);
> +   rv_detach_trace_probe("rtapp_sleep", contention_begin, handle_contention_begin);
> +   rv_detach_trace_probe("rtapp_sleep", contention_end, handle_contention_end);
> +   rv_detach_trace_probe("rtapp_sleep", sched_kthread_stop, handle_kthread_stop);
> +   rv_detach_trace_probe("rtapp_sleep", sys_enter, handle_sys_enter);
> +   rv_detach_trace_probe("rtapp_sleep", sys_exit, handle_sys_exit);
> +
> +   ltl_monitor_destroy();
> +}
> +
> +static struct rv_monitor rv_sleep = {
> +   .name = "sleep",
> +   .description = "Monitor that RT tasks do not undesirably sleep",
> +   .enable = enable_sleep,
> +   .disable = disable_sleep,
> +};
> +
> +static int __init register_sleep(void)
> +{
> +   return rv_register_monitor(&rv_sleep, &rv_rtapp);
> +}
> +
> +static void __exit unregister_sleep(void)
> +{
> +   rv_unregister_monitor(&rv_sleep);
> +}
> +
> +module_init(register_sleep);
> +module_exit(unregister_sleep);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Nam Cao <namcao@...utronix.de>");
> +MODULE_DESCRIPTION("sleep: Monitor that RT tasks do not undesirably sleep");
> diff --git a/kernel/trace/rv/monitors/sleep/sleep.h b/kernel/trace/rv/monitors/sleep/sleep.h
> new file mode 100644
> index 000000000000..d1f990195a20
> --- /dev/null
> +++ b/kernel/trace/rv/monitors/sleep/sleep.h
> @@ -0,0 +1,250 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +
> +#include <linux/rv.h>
> +
> +#define MONITOR_NAME sleep
> +
> +enum ltl_atom {
> +   LTL_ABORT_SLEEP,
> +   LTL_BLOCK_ON_RT_MUTEX,
> +   LTL_CLOCK_NANOSLEEP,
> +   LTL_FUTEX_LOCK_PI,
> +   LTL_FUTEX_WAIT,
> +   LTL_KERNEL_THREAD,
> +   LTL_KTHREAD_SHOULD_STOP,
> +   LTL_NANOSLEEP_CLOCK_MONOTONIC,
> +   LTL_NANOSLEEP_CLOCK_TAI,
> +   LTL_NANOSLEEP_TIMER_ABSTIME,
> +   LTL_RT,
> +   LTL_SLEEP,
> +   LTL_TASK_IS_MIGRATION,
> +   LTL_TASK_IS_RCU,
> +   LTL_WAKE,
> +   LTL_WOKEN_BY_EQUAL_OR_HIGHER_PRIO,
> +   LTL_WOKEN_BY_HARDIRQ,
> +   LTL_WOKEN_BY_NMI,
> +   LTL_NUM_ATOM
> +};
> +static_assert(LTL_NUM_ATOM <= RV_MAX_LTL_ATOM);
> +
> +static const char *ltl_atom_str(enum ltl_atom atom)
> +{
> +   static const char *const names[] = {
> +       "ab_sl",
> +       "bl_on_rt_mu",
> +       "cl_na",
> +       "fu_lo_pi",
> +       "fu_wa",
> +       "ker_th",
> +       "kth_sh_st",
> +       "na_cl_mo",
> +       "na_cl_ta",
> +       "na_ti_ab",
> +       "rt",
> +       "sl",
> +       "ta_mi",
> +       "ta_rc",
> +       "wak",
> +       "wo_eq_hi_pr",
> +       "wo_ha",
> +       "wo_nm",
> +   };
> +
> +   return names[atom];
> +}
> +
> +enum ltl_buchi_state {
> +   S0,
> +   S1,
> +   S2,
> +   S3,
> +   S4,
> +   S5,
> +   S6,
> +   S7,
> +   RV_NUM_BA_STATES
> +};
> +static_assert(RV_NUM_BA_STATES <= RV_MAX_BA_STATES);
> +
> +static void ltl_start(struct task_struct *task, struct ltl_monitor *mon)
> +{
> +   bool task_is_migration = test_bit(LTL_TASK_IS_MIGRATION, mon->atoms);
> +   bool task_is_rcu = test_bit(LTL_TASK_IS_RCU, mon->atoms);
> +   bool val40 = task_is_rcu || task_is_migration;
> +   bool futex_lock_pi = test_bit(LTL_FUTEX_LOCK_PI, mon->atoms);
> +   bool val41 = futex_lock_pi || val40;
> +   bool block_on_rt_mutex = test_bit(LTL_BLOCK_ON_RT_MUTEX, mon->atoms);
> +   bool val5 = block_on_rt_mutex || val41;
> +   bool kthread_should_stop = test_bit(LTL_KTHREAD_SHOULD_STOP, mon->atoms);
> +   bool abort_sleep = test_bit(LTL_ABORT_SLEEP, mon->atoms);
> +   bool val32 = abort_sleep || kthread_should_stop;
> +   bool woken_by_nmi = test_bit(LTL_WOKEN_BY_NMI, mon->atoms);
> +   bool val33 = woken_by_nmi || val32;
> +   bool woken_by_hardirq = test_bit(LTL_WOKEN_BY_HARDIRQ, mon->atoms);
> +   bool val34 = woken_by_hardirq || val33;
> +   bool woken_by_equal_or_higher_prio = test_bit(LTL_WOKEN_BY_EQUAL_OR_HIGHER_PRIO,
> +        mon->atoms);
> +   bool val14 = woken_by_equal_or_higher_prio || val34;
> +   bool wake = test_bit(LTL_WAKE, mon->atoms);
> +   bool val13 = !wake;
> +   bool kernel_thread = test_bit(LTL_KERNEL_THREAD, mon->atoms);
> +   bool nanosleep_clock_tai = test_bit(LTL_NANOSLEEP_CLOCK_TAI, mon->atoms);
> +   bool nanosleep_clock_monotonic = test_bit(LTL_NANOSLEEP_CLOCK_MONOTONIC, mon->atoms);
> +   bool val24 = nanosleep_clock_monotonic || nanosleep_clock_tai;
> +   bool nanosleep_timer_abstime = test_bit(LTL_NANOSLEEP_TIMER_ABSTIME, mon->atoms);
> +   bool val25 = nanosleep_timer_abstime && val24;
> +   bool clock_nanosleep = test_bit(LTL_CLOCK_NANOSLEEP, mon->atoms);
> +   bool val18 = clock_nanosleep && val25;
> +   bool futex_wait = test_bit(LTL_FUTEX_WAIT, mon->atoms);
> +   bool val9 = futex_wait || val18;
> +   bool val11 = val9 || kernel_thread;
> +   bool sleep = test_bit(LTL_SLEEP, mon->atoms);
> +   bool val2 = !sleep;
> +   bool rt = test_bit(LTL_RT, mon->atoms);
> +   bool val1 = !rt;
> +   bool val3 = val1 || val2;
> +
> +   if (val3)
> +       __set_bit(S0, mon->states);
> +   if (val11 && val13)
> +       __set_bit(S1, mon->states);
> +   if (val11 && val14)
> +       __set_bit(S4, mon->states);
> +   if (val5)
> +       __set_bit(S5, mon->states);
> +}
> +
> +static void
> +ltl_possible_next_states(struct ltl_monitor *mon, unsigned int state, unsigned long *next)
> +{
> +   bool task_is_migration = test_bit(LTL_TASK_IS_MIGRATION, mon->atoms);
> +   bool task_is_rcu = test_bit(LTL_TASK_IS_RCU, mon->atoms);
> +   bool val40 = task_is_rcu || task_is_migration;
> +   bool futex_lock_pi = test_bit(LTL_FUTEX_LOCK_PI, mon->atoms);
> +   bool val41 = futex_lock_pi || val40;
> +   bool block_on_rt_mutex = test_bit(LTL_BLOCK_ON_RT_MUTEX, mon->atoms);
> +   bool val5 = block_on_rt_mutex || val41;
> +   bool kthread_should_stop = test_bit(LTL_KTHREAD_SHOULD_STOP, mon->atoms);
> +   bool abort_sleep = test_bit(LTL_ABORT_SLEEP, mon->atoms);
> +   bool val32 = abort_sleep || kthread_should_stop;
> +   bool woken_by_nmi = test_bit(LTL_WOKEN_BY_NMI, mon->atoms);
> +   bool val33 = woken_by_nmi || val32;
> +   bool woken_by_hardirq = test_bit(LTL_WOKEN_BY_HARDIRQ, mon->atoms);
> +   bool val34 = woken_by_hardirq || val33;
> +   bool woken_by_equal_or_higher_prio = test_bit(LTL_WOKEN_BY_EQUAL_OR_HIGHER_PRIO,
> +        mon->atoms);
> +   bool val14 = woken_by_equal_or_higher_prio || val34;
> +   bool wake = test_bit(LTL_WAKE, mon->atoms);
> +   bool val13 = !wake;
> +   bool kernel_thread = test_bit(LTL_KERNEL_THREAD, mon->atoms);
> +   bool nanosleep_clock_tai = test_bit(LTL_NANOSLEEP_CLOCK_TAI, mon->atoms);
> +   bool nanosleep_clock_monotonic = test_bit(LTL_NANOSLEEP_CLOCK_MONOTONIC, mon->atoms);
> +   bool val24 = nanosleep_clock_monotonic || nanosleep_clock_tai;
> +   bool nanosleep_timer_abstime = test_bit(LTL_NANOSLEEP_TIMER_ABSTIME, mon->atoms);
> +   bool val25 = nanosleep_timer_abstime && val24;
> +   bool clock_nanosleep = test_bit(LTL_CLOCK_NANOSLEEP, mon->atoms);
> +   bool val18 = clock_nanosleep && val25;
> +   bool futex_wait = test_bit(LTL_FUTEX_WAIT, mon->atoms);
> +   bool val9 = futex_wait || val18;
> +   bool val11 = val9 || kernel_thread;
> +   bool sleep = test_bit(LTL_SLEEP, mon->atoms);
> +   bool val2 = !sleep;
> +   bool rt = test_bit(LTL_RT, mon->atoms);
> +   bool val1 = !rt;
> +   bool val3 = val1 || val2;
> +
> +   switch (state) {
> +   case S0:
> +       if (val3)
> +           __set_bit(S0, next);
> +       if (val11 && val13)
> +           __set_bit(S1, next);
> +       if (val11 && val14)
> +           __set_bit(S4, next);
> +       if (val5)
> +           __set_bit(S5, next);
> +       break;
> +   case S1:
> +       if (val11 && val13)
> +           __set_bit(S1, next);
> +       if (val13 && val3)
> +           __set_bit(S2, next);
> +       if (val14 && val3)
> +           __set_bit(S3, next);
> +       if (val11 && val14)
> +           __set_bit(S4, next);
> +       if (val13 && val5)
> +           __set_bit(S6, next);
> +       if (val14 && val5)
> +           __set_bit(S7, next);
> +       break;
> +   case S2:
> +       if (val11 && val13)
> +           __set_bit(S1, next);
> +       if (val13 && val3)
> +           __set_bit(S2, next);
> +       if (val14 && val3)
> +           __set_bit(S3, next);
> +       if (val11 && val14)
> +           __set_bit(S4, next);
> +       if (val13 && val5)
> +           __set_bit(S6, next);
> +       if (val14 && val5)
> +           __set_bit(S7, next);
> +       break;
> +   case S3:
> +       if (val3)
> +           __set_bit(S0, next);
> +       if (val11 && val13)
> +           __set_bit(S1, next);
> +       if (val11 && val14)
> +           __set_bit(S4, next);
> +       if (val5)
> +           __set_bit(S5, next);
> +       break;
> +   case S4:
> +       if (val3)
> +           __set_bit(S0, next);
> +       if (val11 && val13)
> +           __set_bit(S1, next);
> +       if (val11 && val14)
> +           __set_bit(S4, next);
> +       if (val5)
> +           __set_bit(S5, next);
> +       break;
> +   case S5:
> +       if (val3)
> +           __set_bit(S0, next);
> +       if (val11 && val13)
> +           __set_bit(S1, next);
> +       if (val11 && val14)
> +           __set_bit(S4, next);
> +       if (val5)
> +           __set_bit(S5, next);
> +       break;
> +   case S6:
> +       if (val11 && val13)
> +           __set_bit(S1, next);
> +       if (val13 && val3)
> +           __set_bit(S2, next);
> +       if (val14 && val3)
> +           __set_bit(S3, next);
> +       if (val11 && val14)
> +           __set_bit(S4, next);
> +       if (val13 && val5)
> +           __set_bit(S6, next);
> +       if (val14 && val5)
> +           __set_bit(S7, next);
> +       break;
> +   case S7:
> +       if (val3)
> +           __set_bit(S0, next);
> +       if (val11 && val13)
> +           __set_bit(S1, next);
> +       if (val11 && val14)
> +           __set_bit(S4, next);
> +       if (val5)
> +           __set_bit(S5, next);
> +       break;
> +   }
> +}
> diff --git a/kernel/trace/rv/monitors/sleep/sleep_trace.h b/kernel/trace/rv/monitors/sleep/sleep_trace.h
> new file mode 100644
> index 000000000000..22eaf31da987
> --- /dev/null
> +++ b/kernel/trace/rv/monitors/sleep/sleep_trace.h
> @@ -0,0 +1,14 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +
> +/*
> + * Snippet to be included in rv_trace.h
> + */
> +
> +#ifdef CONFIG_RV_MON_SLEEP
> +DEFINE_EVENT(event_ltl_monitor_id, event_sleep,
> +        TP_PROTO(struct task_struct *task, char *states, char *atoms, char *next),
> +        TP_ARGS(task, states, atoms, next));
> +DEFINE_EVENT(error_ltl_monitor_id, error_sleep,
> +        TP_PROTO(struct task_struct *task),
> +        TP_ARGS(task));
> +#endif /* CONFIG_RV_MON_SLEEP */
> diff --git a/kernel/trace/rv/rv_trace.h b/kernel/trace/rv/rv_trace.h
> index cfa34af5551b..36ed96868dc4 100644
> --- a/kernel/trace/rv/rv_trace.h
> +++ b/kernel/trace/rv/rv_trace.h
> @@ -173,6 +173,7 @@ TRACE_EVENT(error_ltl_monitor_id,
>     TP_printk("%s[%d]: violation detected", __get_str(comm), __entry->pid)
> );
> #include <monitors/pagefault/pagefault_trace.h>
> +#include <monitors/sleep/sleep_trace.h>
> // Add new monitors based on CONFIG_LTL_MON_EVENTS_ID here
> #endif /* CONFIG_LTL_MON_EVENTS_ID */
> #endif /* _TRACE_RV_H */
> diff --git a/tools/verification/models/rtapp/sleep.ltl b/tools/verification/models/rtapp/sleep.ltl
> new file mode 100644
> index 000000000000..6379bbeb6212
> --- /dev/null
> +++ b/tools/verification/models/rtapp/sleep.ltl
> @@ -0,0 +1,22 @@
> +RULE = always ((RT and SLEEP) imply (RT_FRIENDLY_SLEEP or ALLOWLIST))
> +
> +RT_FRIENDLY_SLEEP = (RT_VALID_SLEEP_REASON or KERNEL_THREAD)
> +                and ((not WAKE) until RT_FRIENDLY_WAKE)
> +
> +RT_VALID_SLEEP_REASON = FUTEX_WAIT
> +                     or RT_FRIENDLY_NANOSLEEP
> +
> +RT_FRIENDLY_NANOSLEEP = CLOCK_NANOSLEEP
> +                    and NANOSLEEP_TIMER_ABSTIME
> +                    and (NANOSLEEP_CLOCK_MONOTONIC or NANOSLEEP_CLOCK_TAI)
> +
> +RT_FRIENDLY_WAKE = WOKEN_BY_EQUAL_OR_HIGHER_PRIO
> +                or WOKEN_BY_HARDIRQ
> +                or WOKEN_BY_NMI
> +                or ABORT_SLEEP
> +                or KTHREAD_SHOULD_STOP
> +
> +ALLOWLIST = BLOCK_ON_RT_MUTEX
> +         or FUTEX_LOCK_PI
> +         or TASK_IS_RCU
> +         or TASK_IS_MIGRATION
> --
> 2.39.5


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