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This patch thus removes the unreachable logic and the would-be unused 'flags' parameter. Signed-off-by: Alan Huang --- kernel/rcu/tree.c | 35 ++--------------------------------- 1 file changed, 2 insertions(+), 33 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index d5507ac1bbf1..b0ea2ebd7769 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -2983,7 +2983,7 @@ static void rcutree_enqueue(struct rcu_data *rdp, struct rcu_head *head, rcu_cal * Handle any core-RCU processing required by a call_rcu() invocation. */ static void call_rcu_core(struct rcu_data *rdp, struct rcu_head *head, - rcu_callback_t func, unsigned long flags) + rcu_callback_t func) { rcutree_enqueue(rdp, head, func); /* @@ -2992,37 +2992,6 @@ static void call_rcu_core(struct rcu_data *rdp, struct rcu_head *head, */ if (!rcu_is_watching()) invoke_rcu_core(); - - /* If interrupts were disabled or CPU offline, don't invoke RCU core. */ - if (irqs_disabled_flags(flags) || cpu_is_offline(smp_processor_id())) - return; - - /* - * Force the grace period if too many callbacks or too long waiting. - * Enforce hysteresis, and don't invoke rcu_force_quiescent_state() - * if some other CPU has recently done so. Also, don't bother - * invoking rcu_force_quiescent_state() if the newly enqueued callback - * is the only one waiting for a grace period to complete. - */ - if (unlikely(rcu_segcblist_n_cbs(&rdp->cblist) > - rdp->qlen_last_fqs_check + qhimark)) { - - /* Are we ignoring a completed grace period? */ - note_gp_changes(rdp); - - /* Start a new grace period if one not already started. */ - if (!rcu_gp_in_progress()) { - rcu_accelerate_cbs_unlocked(rdp->mynode, rdp); - } else { - /* Give the grace period a kick. */ - rdp->blimit = DEFAULT_MAX_RCU_BLIMIT; - if (READ_ONCE(rcu_state.n_force_qs) == rdp->n_force_qs_snap && - rcu_segcblist_first_pend_cb(&rdp->cblist) != head) - rcu_force_quiescent_state(); - rdp->n_force_qs_snap = READ_ONCE(rcu_state.n_force_qs); - rdp->qlen_last_fqs_check = rcu_segcblist_n_cbs(&rdp->cblist); - } - } } /* @@ -3121,7 +3090,7 @@ __call_rcu_common(struct rcu_head *head, rcu_callback_t func, bool lazy_in) if (unlikely(rcu_rdp_is_offloaded(rdp))) call_rcu_nocb(rdp, head, func, flags, lazy); else - call_rcu_core(rdp, head, func, flags); + call_rcu_core(rdp, head, func); local_irq_restore(flags); }