From: Jason Wang <jasowang@redhat.com>
To: mst@redhat.com, jasowang@redhat.com, kvm@vger.kernel.org,
virtualization@lists.linux-foundation.org,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: davem@davemloft.net
Subject: [RFC PATCH V3 1/5] vhost: generalize adding used elem
Date: Sat, 29 Dec 2018 20:46:52 +0800 [thread overview]
Message-ID: <20181229124656.3900-2-jasowang@redhat.com> (raw)
In-Reply-To: <20181229124656.3900-1-jasowang@redhat.com>
Use one generic vhost_copy_to_user() instead of two dedicated
accessor. This will simplify the conversion to fine grain
accessors. About 2% improvement of PPS were seen during vitio-user
txonly test.
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
drivers/vhost/vhost.c | 11 +----------
1 file changed, 1 insertion(+), 10 deletions(-)
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 55e5aa662ad5..f179b5ee14c4 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -2174,16 +2174,7 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq,
start = vq->last_used_idx & (vq->num - 1);
used = vq->used->ring + start;
- if (count == 1) {
- if (vhost_put_user(vq, heads[0].id, &used->id)) {
- vq_err(vq, "Failed to write used id");
- return -EFAULT;
- }
- if (vhost_put_user(vq, heads[0].len, &used->len)) {
- vq_err(vq, "Failed to write used len");
- return -EFAULT;
- }
- } else if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) {
+ if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) {
vq_err(vq, "Failed to write used");
return -EFAULT;
}
--
2.17.1
next prev parent reply other threads:[~2018-12-29 12:47 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-12-29 12:46 [RFC PATCH V3 0/5] Hi: Jason Wang
2018-12-29 12:46 ` Jason Wang [this message]
2019-01-04 21:29 ` [RFC PATCH V3 1/5] vhost: generalize adding used elem Michael S. Tsirkin
2019-01-05 0:33 ` Sean Christopherson
2019-01-07 7:00 ` Jason Wang
2019-01-07 14:50 ` Michael S. Tsirkin
2018-12-29 12:46 ` [RFC PATCH V3 2/5] vhost: fine grain userspace memory accessors Jason Wang
2018-12-29 12:46 ` [RFC PATCH V3 3/5] vhost: rename vq_iotlb_prefetch() to vq_meta_prefetch() Jason Wang
2018-12-29 12:46 ` [RFC PATCH V3 4/5] vhost: introduce helpers to get the size of metadata area Jason Wang
2018-12-29 12:46 ` [RFC PATCH V3 5/5] vhost: access vq metadata through kernel virtual address Jason Wang
2019-01-04 21:34 ` Michael S. Tsirkin
2019-01-07 8:40 ` Jason Wang
2019-01-02 20:47 ` [RFC PATCH V3 0/5] Hi: Michael S. Tsirkin
2019-01-07 2:19 ` Jason Wang
2019-01-07 3:28 ` Michael S. Tsirkin
2019-01-07 3:53 ` Jason Wang
2019-01-07 4:17 ` Michael S. Tsirkin
2019-01-07 6:50 ` Jason Wang
2019-01-07 14:37 ` Michael S. Tsirkin
2019-01-08 10:01 ` Jason Wang
2019-01-07 7:15 ` Dan Williams
2019-01-07 14:11 ` Michael S. Tsirkin
2019-01-07 21:39 ` Dan Williams
2019-01-07 22:25 ` Michael S. Tsirkin
2019-01-07 22:44 ` Dan Williams
2019-01-09 4:31 ` __get_user slower than get_user (was Re: [RFC PATCH V3 0/5] Hi:) Michael S. Tsirkin
2019-01-09 5:19 ` Linus Torvalds
2019-01-08 11:42 ` [RFC PATCH V3 0/5] Hi: Jason Wang
2019-01-04 21:41 ` Michael S. Tsirkin
2019-01-07 6:58 ` Jason Wang
2019-01-07 14:47 ` Michael S. Tsirkin
2019-01-08 10:12 ` Jason Wang
2019-01-11 8:59 ` Jason Wang
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