The comment header for rcu_scheduler_active states that it is used to optimize synchronize_sched() at early boot. This is incorrect. The synchronize_sched() function instead checks the number of online CPUs. This commit therefore replaces the comment's synchronize_sched() with synchronize_rcu(), which really does use rcu_scheduler_active for this purpose.
Reported-by: Lihao Liang <lihao.li...@gmail.com> Signed-off-by: Paul E. McKenney <paul...@linux.vnet.ibm.com> --- kernel/rcu/tree.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index c7f1bc4f817c..0fa692f1094e 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -130,7 +130,7 @@ int rcu_num_nodes __read_mostly = NUM_RCU_NODES; /* Total # rcu_nodes in use. */ * The rcu_scheduler_active variable transitions from zero to one just * before the first task is spawned. So when this variable is zero, RCU * can assume that there is but one task, allowing RCU to (for example) - * optimize synchronize_sched() to a simple barrier(). When this variable + * optimize synchronize_rcu() to a simple barrier(). When this variable * is one, RCU must actually do all the hard work required to detect real * grace periods. This variable is also used to suppress boot-time false * positives from lockdep-RCU error checking. -- 2.5.2
