[ofa-general] Re: [PATCH 02/10] Networking include file changes.

Krishna Kumar2 wrote:

Hi Sridhar,

Sridhar Samudrala [off-list ref] wrote on 07/20/2007 10:55:05 PM:

quoted

quoted

diff -ruNp org/include/net/pkt_sched.h new/include/net/pkt_sched.h

--- org/include/net/pkt_sched.h   2007-07-20 07:49:28.000000000 +0530
+++ new/include/net/pkt_sched.h   2007-07-20 08:30:22.000000000 +0530

@@ -80,13 +80,13 @@ extern struct qdisc_rate_table *qdisc_ge
       struct rtattr *tab);
 extern void qdisc_put_rtab(struct qdisc_rate_table *tab);

-extern void __qdisc_run(struct net_device *dev);
+extern void __qdisc_run(struct net_device *dev, struct sk_buff_head

*blist);

quoted

Why do we need this additional 'blist' argument?
Is this different from dev->skb_blist?

It is the same, but I want to call it mostly with NULL and rarely with the
batch list pointer (so it is related to your other question). My original
code didn't have this and was trying batching in all cases. But in most
xmit's (probably almost all), there will be only one packet in the queue to
send and batching will never happen. When there is a lock contention or if
the queue is stopped, then the next iteration will find >1 packets. But I
still will try no batching for the lock failure case as there be probably
2 packets (one from previous time and 1 from this time, or 3 if two
failures,
etc), and try batching only when queue was stopped from net_tx_action (this
was based on Dave Miller's idea).

Is this right to say that the above change is to get this behavior?
   If qdisc_run() is called from dev_queue_xmit() don't use batching.
   If qdisc_run() is called from net_tx_action(), do batching.

Isn't it possible to have multiple skb's in the qdisc queue in the
first case?

If this additional argument is used to indicate if we should do batching
or not, then passing a flag may be much more cleaner than passing the blist.

Thanks
Sridhar