netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Vijay Subramanian <subramanian.vijay@gmail.com>
To: netdev@vger.kernel.org
Cc: Stephen Hemminger <shemminger@vyatta.com>,
	"David S. Miller" <davem@davemloft.net>,
	Vijay Subramanian <subramanian.vijay@gmail.com>
Subject: [PATCH ] netem: Fix off-by-one bug in reordering
Date: Thu, 19 Jan 2012 12:20:59 -0800	[thread overview]
Message-ID: <1327004459-19275-1-git-send-email-subramanian.vijay@gmail.com> (raw)

With netem reordering, a gap of N is supposed to reorder every Nth packet with
given reorder probability.  However, the code currently skips N packets and
reorders every (N+1)th packet.

Signed-off-by: Vijay Subramanian <subramanian.vijay@gmail.com>
---
 net/sched/sch_netem.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index e7e1d0b..2776012 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -419,7 +419,7 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 
 	cb = netem_skb_cb(skb);
 	if (q->gap == 0 ||		/* not doing reordering */
-	    q->counter < q->gap ||	/* inside last reordering gap */
+	    q->counter < q->gap - 1 ||	/* inside last reordering gap */
 	    q->reorder < get_crandom(&q->reorder_cor)) {
 		psched_time_t now;
 		psched_tdiff_t delay;
-- 
1.7.0.4

             reply	other threads:[~2012-01-19 20:16 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-19 20:20 Vijay Subramanian [this message]
2012-01-22 19:23 ` [PATCH ] netem: Fix off-by-one bug in reordering David Miller

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1327004459-19275-1-git-send-email-subramanian.vijay@gmail.com \
    --to=subramanian.vijay@gmail.com \
    --cc=davem@davemloft.net \
    --cc=netdev@vger.kernel.org \
    --cc=shemminger@vyatta.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).