From: Zqiang <qiang1.zhang@xxxxxxxxx>
[ Upstream commit db7b464df9d820186e98a65aa6a10f0d51fbf8ce ]
This commit adds checks for the TICK_DEP_MASK_RCU_EXP bit, thus enabling
RCU expedited grace periods to actually force-enable scheduling-clock
interrupts on holdout CPUs.
Fixes: df1e849ae455 ("rcu: Enable tick for nohz_full CPUs slow to provide expedited QS")
Signed-off-by: Zqiang <qiang1.zhang@xxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Anna-Maria Behnsen <anna-maria@xxxxxxxxxxxxx>
Acked-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
include/trace/events/timer.h | 3 ++-
kernel/time/tick-sched.c | 5 +++++
2 files changed, 7 insertions(+), 1 deletion(-)
diff --git a/include/trace/events/timer.h b/include/trace/events/timer.h
index 6ad031c71be74..1cf012de6442e 100644
--- a/include/trace/events/timer.h
+++ b/include/trace/events/timer.h
@@ -368,7 +368,8 @@ TRACE_EVENT(itimer_expire,
tick_dep_name(PERF_EVENTS) \
tick_dep_name(SCHED) \
tick_dep_name(CLOCK_UNSTABLE) \
- tick_dep_name_end(RCU)
+ tick_dep_name(RCU) \
+ tick_dep_name_end(RCU_EXP)
#undef tick_dep_name
#undef tick_dep_mask_name
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 63e3e8ebcd643..e014927c82e76 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -264,6 +264,11 @@ static bool check_tick_dependency(atomic_t *dep)
return true;
}
+ if (val & TICK_DEP_MASK_RCU_EXP) {
+ trace_tick_stop(0, TICK_DEP_MASK_RCU_EXP);
+ return true;
+ }
+
return false;
}
--
2.39.2
