From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH net-next V2] tun/macvtap: use consume_skb() instead of kfree_skb() when needed Date: Wed, 26 Nov 2014 15:47:42 +0200 Message-ID: <20141126134742.GA5358@redhat.com> References: <1416987810-23263-1-git-send-email-jasowang@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Eric Dumazet To: Jason Wang Return-path: Content-Disposition: inline In-Reply-To: <1416987810-23263-1-git-send-email-jasowang@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Wed, Nov 26, 2014 at 03:43:30PM +0800, Jason Wang wrote: > To be more friendly with drop monitor, we should only call kfree_skb() when > the packets were dropped and use consume_skb() in other cases. > > Cc: Eric Dumazet > Signed-off-by: Jason Wang > --- > Changes from V1: > - check the return value of tun/macvtap_put_user() > --- > drivers/net/macvtap.c | 5 ++++- > drivers/net/tun.c | 5 ++++- > 2 files changed, 8 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c > index 42a80d3..c171ab6 100644 > --- a/drivers/net/macvtap.c > +++ b/drivers/net/macvtap.c > @@ -862,7 +862,10 @@ static ssize_t macvtap_do_read(struct macvtap_queue *q, > } > iov_iter_init(&iter, READ, iv, segs, len); > ret = macvtap_put_user(q, skb, &iter); > - kfree_skb(skb); > + if (ret < 0) Maybe unlikely() here? > + kfree_skb(skb); > + else > + consume_skb(skb); > break; > } > > diff --git a/drivers/net/tun.c b/drivers/net/tun.c > index ac53a73..a21c130 100644 > --- a/drivers/net/tun.c > +++ b/drivers/net/tun.c > @@ -1363,7 +1363,10 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile, > > iov_iter_init(&iter, READ, iv, segs, len); > ret = tun_put_user(tun, tfile, skb, &iter); > - kfree_skb(skb); > + if (ret < 0) > + kfree_skb(skb); > + else > + consume_skb(skb); > > return ret; > } > -- > 1.9.1