diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/lguest/lguest.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c index 84c471b07c2..20f8253881b 100644 --- a/Documentation/lguest/lguest.c +++ b/Documentation/lguest/lguest.c | |||
@@ -151,6 +151,9 @@ struct virtqueue | |||
151 | /* Last available index we saw. */ | 151 | /* Last available index we saw. */ |
152 | u16 last_avail_idx; | 152 | u16 last_avail_idx; |
153 | 153 | ||
154 | /* How many are used since we sent last irq? */ | ||
155 | unsigned int pending_used; | ||
156 | |||
154 | /* Eventfd where Guest notifications arrive. */ | 157 | /* Eventfd where Guest notifications arrive. */ |
155 | int eventfd; | 158 | int eventfd; |
156 | 159 | ||
@@ -556,6 +559,11 @@ static void trigger_irq(struct virtqueue *vq) | |||
556 | { | 559 | { |
557 | unsigned long buf[] = { LHREQ_IRQ, vq->config.irq }; | 560 | unsigned long buf[] = { LHREQ_IRQ, vq->config.irq }; |
558 | 561 | ||
562 | /* Don't inform them if nothing used. */ | ||
563 | if (!vq->pending_used) | ||
564 | return; | ||
565 | vq->pending_used = 0; | ||
566 | |||
559 | /* If they don't want an interrupt, don't send one, unless empty. */ | 567 | /* If they don't want an interrupt, don't send one, unless empty. */ |
560 | if ((vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT) | 568 | if ((vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT) |
561 | && lg_last_avail(vq) != vq->vring.avail->idx) | 569 | && lg_last_avail(vq) != vq->vring.avail->idx) |
@@ -647,6 +655,7 @@ static void add_used(struct virtqueue *vq, unsigned int head, int len) | |||
647 | /* Make sure buffer is written before we update index. */ | 655 | /* Make sure buffer is written before we update index. */ |
648 | wmb(); | 656 | wmb(); |
649 | vq->vring.used->idx++; | 657 | vq->vring.used->idx++; |
658 | vq->pending_used++; | ||
650 | } | 659 | } |
651 | 660 | ||
652 | /* And here's the combo meal deal. Supersize me! */ | 661 | /* And here's the combo meal deal. Supersize me! */ |