From: Huawei Xie <huawei.xie@intel.com>
To: dev@dpdk.org
Subject: [dpdk-dev] [RFC PATCH] avail idx update optimizations
Date: Fri, 22 Apr 2016 01:18:12 +0800 [thread overview]
Message-ID: <1461259092-9309-1-git-send-email-huawei.xie@intel.com> (raw)
eliminate unnecessary cache to cache transfer between virtio and vhost
core
---
drivers/net/virtio/virtqueue.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/virtio/virtqueue.h b/drivers/net/virtio/virtqueue.h
index 4e9239e..8c46a83 100644
--- a/drivers/net/virtio/virtqueue.h
+++ b/drivers/net/virtio/virtqueue.h
@@ -302,7 +302,8 @@ vq_update_avail_ring(struct virtqueue *vq, uint16_t desc_idx)
* descriptor.
*/
avail_idx = (uint16_t)(vq->vq_avail_idx & (vq->vq_nentries - 1));
- vq->vq_ring.avail->ring[avail_idx] = desc_idx;
+ if (unlikely(vq->vq_ring.avail->ring[avail_idx] != desc_idx))
+ vq->vq_ring.avail->ring[avail_idx] = desc_idx;
vq->vq_avail_idx++;
}
--
2.4.3
next reply other threads:[~2016-04-22 9:12 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-04-21 17:18 Huawei Xie [this message]
[not found] ` <C37D651A908B024F974696C65296B57B4C713327@SHSMSX101.ccr.corp.intel.com>
2016-04-24 2:45 ` Xie, Huawei
2016-04-24 9:15 ` Michael S. Tsirkin
2016-04-24 13:23 ` Xie, Huawei
2016-04-28 9:17 ` Xie, Huawei
2016-04-27 8:53 ` [dpdk-dev] [PATCH] virtio: avoid avail ring entry index update if equal Huawei Xie
2016-04-28 6:19 ` Yuanhan Liu
2016-04-28 8:14 ` Thomas Monjalon
2016-04-28 13:15 ` Xie, Huawei
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