From: Paul E. McKenney Date: Thu, 29 Jul 2021 22:35:21 +0000 (-0700) Subject: rcu: Simplify rcu_report_dead() call to rcu_report_exp_rdp() X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=768f5d50e6ad88363291f96a2e230442b8d633bc;p=uclinux-h8%2Flinux.git rcu: Simplify rcu_report_dead() call to rcu_report_exp_rdp() Currently, rcu_report_dead() disables preemption across its call to rcu_report_exp_rdp(), but this is pointless because interrupts are already disabled by the caller. In addition, rcu_report_dead() computes the address of the outgoing CPU's rcu_data structure, which is also pointless because this address is already present in local variable rdp. This commit therefore drops the preemption disabling and passes rdp to rcu_report_exp_rdp(). Signed-off-by: Paul E. McKenney --- diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 801075e36515..dc2968473593 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -4294,9 +4294,7 @@ void rcu_report_dead(unsigned int cpu) do_nocb_deferred_wakeup(rdp); /* QS for any half-done expedited grace period. */ - preempt_disable(); - rcu_report_exp_rdp(this_cpu_ptr(&rcu_data)); - preempt_enable(); + rcu_report_exp_rdp(rdp); rcu_preempt_deferred_qs(current); /* Remove outgoing CPU from mask in the leaf rcu_node structure. */