> monitor_todo is not needed as the work struct already tracks if work is
> pending. Just use that to know if work is pending using
> delayed_work_pending() helper.
>
> Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
> ---
> kernel/rcu/tree.c | 22 +++++++---------------
> 1 file changed, 7 insertions(+), 15 deletions(-)
>
> diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
> index 3baf29014f86..3828ac3bf1c4 100644
> --- a/kernel/rcu/tree.c
> +++ b/kernel/rcu/tree.c
> @@ -3155,7 +3155,6 @@ struct kfree_rcu_cpu_work {
> * @krw_arr: Array of batches of kfree_rcu() objects waiting for a grace period
> * @lock: Synchronize access to this structure
> * @monitor_work: Promote @head to @head_free after KFREE_DRAIN_JIFFIES
> - * @monitor_todo: Tracks whether a @monitor_work delayed work is pending
> * @initialized: The @rcu_work fields have been initialized
> * @count: Number of objects for which GP not started
> * @bkvcache:
> @@ -3180,7 +3179,6 @@ struct kfree_rcu_cpu {
> struct kfree_rcu_cpu_work krw_arr[KFREE_N_BATCHES];
> raw_spinlock_t lock;
> struct delayed_work monitor_work;
> - bool monitor_todo;
> bool initialized;
> int count;
>
> @@ -3416,9 +3414,7 @@ static void kfree_rcu_monitor(struct work_struct *work)
> // of the channels that is still busy we should rearm the
> // work to repeat an attempt. Because previous batches are
> // still in progress.
> - if (!krcp->bkvhead[0] && !krcp->bkvhead[1] && !krcp->head)
> - krcp->monitor_todo = false;
> - else
> + if (krcp->bkvhead[0] || krcp->bkvhead[1] || krcp->head)
> schedule_delayed_work(&krcp->monitor_work, KFREE_DRAIN_JIFFIES);
>
> raw_spin_unlock_irqrestore(&krcp->lock, flags);
> @@ -3607,10 +3603,8 @@ void kvfree_call_rcu(struct rcu_head *head, rcu_callback_t func)
>
> // Set timer to drain after KFREE_DRAIN_JIFFIES.
> if (rcu_scheduler_active == RCU_SCHEDULER_RUNNING &&
> - !krcp->monitor_todo) {
> - krcp->monitor_todo = true;
> + !delayed_work_pending(&krcp->monitor_work))
> schedule_delayed_work(&krcp->monitor_work, KFREE_DRAIN_JIFFIES);
> - }
>
> unlock_return:
> krc_this_cpu_unlock(krcp, flags);
> @@ -3685,14 +3679,12 @@ void __init kfree_rcu_scheduler_running(void)
> struct kfree_rcu_cpu *krcp = per_cpu_ptr(&krc, cpu);
>
> raw_spin_lock_irqsave(&krcp->lock, flags);
> - if ((!krcp->bkvhead[0] && !krcp->bkvhead[1] && !krcp->head) ||
> - krcp->monitor_todo) {
> - raw_spin_unlock_irqrestore(&krcp->lock, flags);
> - continue;
> + if (krcp->bkvhead[0] || krcp->bkvhead[1] || krcp->head) {
> + if (delayed_work_pending(&krcp->monitor_work)) {
> + schedule_delayed_work_on(cpu, &krcp->monitor_work,
> + KFREE_DRAIN_JIFFIES);
> + }
> }
> - krcp->monitor_todo = true;
> - schedule_delayed_work_on(cpu, &krcp->monitor_work,
> - KFREE_DRAIN_JIFFIES);
> raw_spin_unlock_irqrestore(&krcp->lock, flags);
> }
> }
> --
>
Looks good to me from the first glance, but let me know to have a look
at it more closely.
--
Uladzislau Rezki
