diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c index 3e1a8a675572..41c605b0058f 100644 --- a/drivers/iommu/iova.c +++ b/drivers/iommu/iova.c @@ -577,7 +577,9 @@ void queue_iova(struct iova_domain *iovad, spin_unlock_irqrestore(&fq->lock, flags); - if (atomic_cmpxchg(&iovad->fq_timer_on, 0, 1) == 0) + /* Avoid false sharing as much as possible. */ + if (!atomic_read(&iovad->fq_timer_on) && + !atomic_cmpxchg(&iovad->fq_timer_on, 0, 1)) mod_timer(&iovad->fq_timer, jiffies + msecs_to_jiffies(IOVA_FQ_TIMEOUT)); }