[PATCH v2] rv: Allow epoll in rtapp-sleep monitor

Nam Cao posted 1 patch 5 hours ago
kernel/trace/rv/monitors/sleep/sleep.c    |  8 ++
kernel/trace/rv/monitors/sleep/sleep.h    | 98 ++++++++++++-----------
tools/verification/models/rtapp/sleep.ltl |  1 +
3 files changed, 61 insertions(+), 46 deletions(-)
[PATCH v2] rv: Allow epoll in rtapp-sleep monitor
Posted by Nam Cao 5 hours ago
Since commit 0c43094f8cc9 ("eventpoll: Replace rwlock with spinlock"),
epoll_wait is real-time-safe syscall for sleeping.

Add epoll_wait to the list of rt-safe sleeping APIs.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
---
v2: Use ltl_atom_update() instead of ltl_atom_set() in handle_sys_enter()
---
 kernel/trace/rv/monitors/sleep/sleep.c    |  8 ++
 kernel/trace/rv/monitors/sleep/sleep.h    | 98 ++++++++++++-----------
 tools/verification/models/rtapp/sleep.ltl |  1 +
 3 files changed, 61 insertions(+), 46 deletions(-)

diff --git a/kernel/trace/rv/monitors/sleep/sleep.c b/kernel/trace/rv/monitors/sleep/sleep.c
index c1347da69e9d..8dfe5ec13e19 100644
--- a/kernel/trace/rv/monitors/sleep/sleep.c
+++ b/kernel/trace/rv/monitors/sleep/sleep.c
@@ -49,6 +49,7 @@ static void ltl_atoms_init(struct task_struct *task, struct ltl_monitor *mon, bo
 		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_EPOLL_WAIT, false);
 		ltl_atom_set(mon, LTL_FUTEX_LOCK_PI, false);
 		ltl_atom_set(mon, LTL_BLOCK_ON_RT_MUTEX, false);
 	}
@@ -63,6 +64,7 @@ static void ltl_atoms_init(struct task_struct *task, struct ltl_monitor *mon, bo
 		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_EPOLL_WAIT, false);
 
 		if (strstarts(task->comm, "migration/"))
 			ltl_atom_set(mon, LTL_TASK_IS_MIGRATION, true);
@@ -162,6 +164,11 @@ static void handle_sys_enter(void *data, struct pt_regs *regs, long id)
 			break;
 		}
 		break;
+#ifdef __NR_epoll_wait
+	case __NR_epoll_wait:
+		ltl_atom_update(current, LTL_EPOLL_WAIT, true);
+		break;
+#endif
 	}
 }
 
@@ -174,6 +181,7 @@ static void handle_sys_exit(void *data, struct pt_regs *regs, long ret)
 	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_EPOLL_WAIT, false);
 	ltl_atom_update(current, LTL_CLOCK_NANOSLEEP, false);
 }
 
diff --git a/kernel/trace/rv/monitors/sleep/sleep.h b/kernel/trace/rv/monitors/sleep/sleep.h
index 2ab46fd218d2..95dc2727c059 100644
--- a/kernel/trace/rv/monitors/sleep/sleep.h
+++ b/kernel/trace/rv/monitors/sleep/sleep.h
@@ -15,6 +15,7 @@ enum ltl_atom {
 	LTL_ABORT_SLEEP,
 	LTL_BLOCK_ON_RT_MUTEX,
 	LTL_CLOCK_NANOSLEEP,
+	LTL_EPOLL_WAIT,
 	LTL_FUTEX_LOCK_PI,
 	LTL_FUTEX_WAIT,
 	LTL_KERNEL_THREAD,
@@ -40,6 +41,7 @@ static const char *ltl_atom_str(enum ltl_atom atom)
 		"ab_sl",
 		"bl_on_rt_mu",
 		"cl_na",
+		"ep_wa",
 		"fu_lo_pi",
 		"fu_wa",
 		"ker_th",
@@ -75,39 +77,41 @@ 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 task_is_rcu = test_bit(LTL_TASK_IS_RCU, mon->atoms);
+	bool task_is_migration = test_bit(LTL_TASK_IS_MIGRATION, mon->atoms);
+	bool sleep = test_bit(LTL_SLEEP, mon->atoms);
+	bool rt = test_bit(LTL_RT, mon->atoms);
+	bool nanosleep_timer_abstime = test_bit(LTL_NANOSLEEP_TIMER_ABSTIME, 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 kthread_should_stop = test_bit(LTL_KTHREAD_SHOULD_STOP, mon->atoms);
+	bool kernel_thread = test_bit(LTL_KERNEL_THREAD, mon->atoms);
 	bool futex_wait = test_bit(LTL_FUTEX_WAIT, mon->atoms);
-	bool val9 = futex_wait || val18;
+	bool futex_lock_pi = test_bit(LTL_FUTEX_LOCK_PI, mon->atoms);
+	bool epoll_wait = test_bit(LTL_EPOLL_WAIT, mon->atoms);
+	bool clock_nanosleep = test_bit(LTL_CLOCK_NANOSLEEP, mon->atoms);
+	bool block_on_rt_mutex = test_bit(LTL_BLOCK_ON_RT_MUTEX, mon->atoms);
+	bool abort_sleep = test_bit(LTL_ABORT_SLEEP, mon->atoms);
+	bool val42 = task_is_rcu || task_is_migration;
+	bool val43 = futex_lock_pi || val42;
+	bool val5 = block_on_rt_mutex || val43;
+	bool val34 = abort_sleep || kthread_should_stop;
+	bool val35 = woken_by_nmi || val34;
+	bool val36 = woken_by_hardirq || val35;
+	bool val14 = woken_by_equal_or_higher_prio || val36;
+	bool val13 = !wake;
+	bool val26 = nanosleep_clock_monotonic || nanosleep_clock_tai;
+	bool val27 = nanosleep_timer_abstime && val26;
+	bool val18 = clock_nanosleep && val27;
+	bool val20 = val18 || epoll_wait;
+	bool val9 = futex_wait || val20;
 	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;
 
@@ -124,39 +128,41 @@ static void ltl_start(struct task_struct *task, struct ltl_monitor *mon)
 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 task_is_rcu = test_bit(LTL_TASK_IS_RCU, mon->atoms);
+	bool task_is_migration = test_bit(LTL_TASK_IS_MIGRATION, mon->atoms);
+	bool sleep = test_bit(LTL_SLEEP, mon->atoms);
+	bool rt = test_bit(LTL_RT, mon->atoms);
+	bool nanosleep_timer_abstime = test_bit(LTL_NANOSLEEP_TIMER_ABSTIME, 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 kthread_should_stop = test_bit(LTL_KTHREAD_SHOULD_STOP, mon->atoms);
+	bool kernel_thread = test_bit(LTL_KERNEL_THREAD, mon->atoms);
 	bool futex_wait = test_bit(LTL_FUTEX_WAIT, mon->atoms);
-	bool val9 = futex_wait || val18;
+	bool futex_lock_pi = test_bit(LTL_FUTEX_LOCK_PI, mon->atoms);
+	bool epoll_wait = test_bit(LTL_EPOLL_WAIT, mon->atoms);
+	bool clock_nanosleep = test_bit(LTL_CLOCK_NANOSLEEP, mon->atoms);
+	bool block_on_rt_mutex = test_bit(LTL_BLOCK_ON_RT_MUTEX, mon->atoms);
+	bool abort_sleep = test_bit(LTL_ABORT_SLEEP, mon->atoms);
+	bool val42 = task_is_rcu || task_is_migration;
+	bool val43 = futex_lock_pi || val42;
+	bool val5 = block_on_rt_mutex || val43;
+	bool val34 = abort_sleep || kthread_should_stop;
+	bool val35 = woken_by_nmi || val34;
+	bool val36 = woken_by_hardirq || val35;
+	bool val14 = woken_by_equal_or_higher_prio || val36;
+	bool val13 = !wake;
+	bool val26 = nanosleep_clock_monotonic || nanosleep_clock_tai;
+	bool val27 = nanosleep_timer_abstime && val26;
+	bool val18 = clock_nanosleep && val27;
+	bool val20 = val18 || epoll_wait;
+	bool val9 = futex_wait || val20;
 	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;
 
diff --git a/tools/verification/models/rtapp/sleep.ltl b/tools/verification/models/rtapp/sleep.ltl
index 6379bbeb6212..6f26c4810f78 100644
--- a/tools/verification/models/rtapp/sleep.ltl
+++ b/tools/verification/models/rtapp/sleep.ltl
@@ -5,6 +5,7 @@ RT_FRIENDLY_SLEEP = (RT_VALID_SLEEP_REASON or KERNEL_THREAD)
 
 RT_VALID_SLEEP_REASON = FUTEX_WAIT
                      or RT_FRIENDLY_NANOSLEEP
+                     or EPOLL_WAIT
 
 RT_FRIENDLY_NANOSLEEP = CLOCK_NANOSLEEP
                     and NANOSLEEP_TIMER_ABSTIME
-- 
2.47.3