From: Zqiang qiang1.zhang@intel.com
[ 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@intel.com Cc: Steven Rostedt rostedt@goodmis.org Cc: Masami Hiramatsu mhiramat@kernel.org Cc: Frederic Weisbecker fweisbec@gmail.com Cc: Thomas Gleixner tglx@linutronix.de Cc: Ingo Molnar mingo@kernel.org Cc: Anna-Maria Behnsen anna-maria@linutronix.de Acked-by: Frederic Weisbecker frederic@kernel.org Signed-off-by: Paul E. McKenney paulmck@kernel.org Signed-off-by: Joel Fernandes (Google) joel@joelfernandes.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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; }