From 564506495ca96a6e66d077d3d5b9f02d4b9b0f45 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Wed, 8 Jun 2022 16:40:32 +0200 Subject: rcu/context-tracking: Move deferred nocb resched to context tracking To prepare for migrating the RCU eqs accounting code to context tracking, split the last-resort deferred nocb resched from rcu_user_enter() and move it into a separate call from context tracking. Acked-by: Paul E. McKenney Signed-off-by: Frederic Weisbecker Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Neeraj Upadhyay Cc: Uladzislau Rezki Cc: Joel Fernandes Cc: Boqun Feng Cc: Nicolas Saenz Julienne Cc: Marcelo Tosatti Cc: Xiongfeng Wang Cc: Yu Liao Cc: Phil Auld Cc: Paul Gortmaker Cc: Alex Belits Signed-off-by: Paul E. McKenney Reviewed-by: Nicolas Saenz Julienne Tested-by: Nicolas Saenz Julienne --- kernel/context_tracking.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'kernel/context_tracking.c') diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c index 7c3033e9a518..8cf59d8a6af6 100644 --- a/kernel/context_tracking.c +++ b/kernel/context_tracking.c @@ -177,6 +177,8 @@ static __always_inline void context_tracking_recursion_exit(void) */ void noinstr __ct_user_enter(enum ctx_state state) { + lockdep_assert_irqs_disabled(); + /* Kernel threads aren't supposed to go to userspace */ WARN_ON_ONCE(!current->mm); @@ -198,6 +200,12 @@ void noinstr __ct_user_enter(enum ctx_state state) vtime_user_enter(current); instrumentation_end(); } + /* + * Other than generic entry implementation, we may be past the last + * rescheduling opportunity in the entry code. Trigger a self IPI + * that will fire and reschedule once we resume in user/guest mode. + */ + rcu_irq_work_resched(); rcu_user_enter(); } /* -- cgit v1.2.3