diff mbox series

[ovs-dev,15/23] datapath: don't call pad_packet if not necessary

Message ID 1597963790-12362-16-git-send-email-gvrose8192@gmail.com
State Superseded
Headers show
Series Add support for Linux kernels up to 5.9.x | expand

Commit Message

Gregory Rose Aug. 20, 2020, 10:49 p.m. UTC 
From: Tonghao Zhang <xiangxia.m.yue@gmail.com>

Upstream commit:
    commit 61ca533c0e94104c35fcb7858a23ec9a05d78143
    Author: Tonghao Zhang <xiangxia.m.yue@gmail.com>
    Date:   Thu Nov 14 23:51:08 2019 +0800

    net: openvswitch: don't call pad_packet if not necessary

    The nla_put_u16/nla_put_u32 makes sure that
    *attrlen is align. The call tree is that:

    nla_put_u16/nla_put_u32
      -> nla_put		attrlen = sizeof(u16) or sizeof(u32)
      -> __nla_put		attrlen
      -> __nla_reserve	attrlen
      -> skb_put(skb, nla_total_size(attrlen))

    nla_total_size returns the total length of attribute
    including padding.

    Cc: Joe Stringer <joe@ovn.org>
    Cc: William Tu <u9012063@gmail.com>
    Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
    Acked-by: Pravin B Shelar <pshelar@ovn.org>
    Signed-off-by: David S. Miller <davem@davemloft.net>

Cc: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Signed-off-by: Greg Rose <gvrose8192@gmail.com>
---
 datapath/datapath.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

Comments

Tonghao Zhang Aug. 25, 2020, 4:01 a.m. UTC | #1 
On Fri, Aug 21, 2020 at 6:50 AM Greg Rose <gvrose8192@gmail.com> wrote:
>
> From: Tonghao Zhang <xiangxia.m.yue@gmail.com>
>
> Upstream commit:
>     commit 61ca533c0e94104c35fcb7858a23ec9a05d78143
>     Author: Tonghao Zhang <xiangxia.m.yue@gmail.com>
>     Date:   Thu Nov 14 23:51:08 2019 +0800
>
>     net: openvswitch: don't call pad_packet if not necessary
>
>     The nla_put_u16/nla_put_u32 makes sure that
>     *attrlen is align. The call tree is that:
>
>     nla_put_u16/nla_put_u32
>       -> nla_put                attrlen = sizeof(u16) or sizeof(u32)
>       -> __nla_put              attrlen
>       -> __nla_reserve  attrlen
>       -> skb_put(skb, nla_total_size(attrlen))
>
>     nla_total_size returns the total length of attribute
>     including padding.
>
>     Cc: Joe Stringer <joe@ovn.org>
>     Cc: William Tu <u9012063@gmail.com>
>     Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
>     Acked-by: Pravin B Shelar <pshelar@ovn.org>
>     Signed-off-by: David S. Miller <davem@davemloft.net>
>
> Cc: Tonghao Zhang <xiangxia.m.yue@gmail.com>
> Signed-off-by: Greg Rose <gvrose8192@gmail.com>
Reviewed-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
> ---
>  datapath/datapath.c | 22 ++++++++--------------
>  1 file changed, 8 insertions(+), 14 deletions(-)
>
> diff --git a/datapath/datapath.c b/datapath/datapath.c
> index f04ce21..b9ac676 100644
> --- a/datapath/datapath.c
> +++ b/datapath/datapath.c
> @@ -512,23 +512,17 @@ static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
>         }
>
>         /* Add OVS_PACKET_ATTR_MRU */
> -       if (upcall_info->mru) {
> -               if (nla_put_u16(user_skb, OVS_PACKET_ATTR_MRU,
> -                               upcall_info->mru)) {
> -                       err = -ENOBUFS;
> -                       goto out;
> -               }
> -               pad_packet(dp, user_skb);
> +       if (upcall_info->mru &&
> +           nla_put_u16(user_skb, OVS_PACKET_ATTR_MRU, upcall_info->mru)) {
> +               err = -ENOBUFS;
> +               goto out;
>         }
>
>         /* Add OVS_PACKET_ATTR_LEN when packet is truncated */
> -       if (cutlen > 0) {
> -               if (nla_put_u32(user_skb, OVS_PACKET_ATTR_LEN,
> -                               skb->len)) {
> -                       err = -ENOBUFS;
> -                       goto out;
> -               }
> -               pad_packet(dp, user_skb);
> +       if (cutlen > 0 &&
> +           nla_put_u32(user_skb, OVS_PACKET_ATTR_LEN, skb->len)) {
> +               err = -ENOBUFS;
> +               goto out;
>         }
>
>         /* Add OVS_PACKET_ATTR_HASH */
> --
> 1.8.3.1
>
diff mbox series

Patch

diff --git a/datapath/datapath.c b/datapath/datapath.c
index f04ce21..b9ac676 100644
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -512,23 +512,17 @@  static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
 	}
 
 	/* Add OVS_PACKET_ATTR_MRU */
-	if (upcall_info->mru) {
-		if (nla_put_u16(user_skb, OVS_PACKET_ATTR_MRU,
-				upcall_info->mru)) {
-			err = -ENOBUFS;
-			goto out;
-		}
-		pad_packet(dp, user_skb);
+	if (upcall_info->mru &&
+	    nla_put_u16(user_skb, OVS_PACKET_ATTR_MRU, upcall_info->mru)) {
+		err = -ENOBUFS;
+		goto out;
 	}
 
 	/* Add OVS_PACKET_ATTR_LEN when packet is truncated */
-	if (cutlen > 0) {
-		if (nla_put_u32(user_skb, OVS_PACKET_ATTR_LEN,
-				skb->len)) {
-			err = -ENOBUFS;
-			goto out;
-		}
-		pad_packet(dp, user_skb);
+	if (cutlen > 0 &&
+	    nla_put_u32(user_skb, OVS_PACKET_ATTR_LEN, skb->len)) {
+		err = -ENOBUFS;
+		goto out;
 	}
 
 	/* Add OVS_PACKET_ATTR_HASH */