From: "Paul E. McKenney" <[email protected]> This commit adds READ_ONCE() to a lockless diagnostic read from rcu_state.gp_flags to avoid giving the compiler any chance whatsoever of confusing the diagnostic state printed.
Signed-off-by: Paul E. McKenney <[email protected]> Signed-off-by: Uladzislau Rezki (Sony) <[email protected]> --- kernel/rcu/tree_stall.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/rcu/tree_stall.h b/kernel/rcu/tree_stall.h index 5d666428546b..62b2c4858028 100644 --- a/kernel/rcu/tree_stall.h +++ b/kernel/rcu/tree_stall.h @@ -579,7 +579,7 @@ static void rcu_check_gp_kthread_expired_fqs_timer(void) pr_err("%s kthread timer wakeup didn't happen for %ld jiffies! g%ld f%#x %s(%d) ->state=%#x\n", rcu_state.name, (jiffies - jiffies_fqs), (long)rcu_seq_current(&rcu_state.gp_seq), - data_race(rcu_state.gp_flags), + data_race(READ_ONCE(rcu_state.gp_flags)), // Diagnostic read gp_state_getname(RCU_GP_WAIT_FQS), RCU_GP_WAIT_FQS, data_race(READ_ONCE(gpk->__state))); pr_err("\tPossible timer handling issue on cpu=%d timer-softirq=%u\n", -- 2.39.2
