Subject: Re: [PATCH] sched: Optimize return value of qdisc_restart

From: jamal <[email-masked]>
Date: Thu, 10 May 2007 09:18:04 -0400

On Thu, 2007-10-05 at 22:59 +1000, Herbert Xu wrote:
> jamal <[email-masked]> wrote:

> 			This release qlock isn't in our source code :)

This is why i defered this to you ;-> 
For completion sake, this is how it looks like:
 
 CPU0                 CPU1
  | wait qlock         |
  |                    |
  |                    + find that return code is 0
  |                    + release qdisc running
  |                    + release qlock
  + grab qlock         + ==> outta here
  | enq pktx           |
  | call qdisc_run     |
  +  grab running
  |  deq etc
  +  release running
  + release qlock
  + ==> outta here    

I wonder how much performance improvement this give now that the extra
incursion into qdisc_restart is avoided.

cheers,
jamal