Cc: Steven Rostedt <rostedt@goodmis.org>, LKML <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@linux-foundation.org>,
       Thomas Gleixner <tglx@linutronix.de>,
       Christoph Hellwig <hch@infradead.org>,
       john stultz <johnstul@us.ibm.com>, Oleg Nesterov <oleg@tv-sign.ru>,
       "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
       Dipankar Sarma <dipankar@in.ibm.com>,
       "David S. Miller" <davem@davemloft.net>, matthew.wilcox@hp.com,
       kuznet@ms2.inr.ac.ru, Linus Torvalds <torvalds@linux-foundation.org>
To: Ingo Molnar <mingo@elte.hu>
Subject: Re: [RFC PATCH 0/6] Convert all tasklets to workqueues 
From: corbet@lwn.net (Jonathan Corbet)
In-reply-to: Your message of "Sun, 24 Jun 2007 09:16:07 MDT."
             <10876.1182698167@lwn.net> 
Date: Mon, 25 Jun 2007 18:00:12 -0600
Message-ID: <10203.1182816012@lwn.net>
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 977
Lines: 27

A couple of days ago I said:

> The cafe_ccic (OLPC) camera driver uses a tasklet to move frames out of
> the DMA buffers in the streaming I/O path....
> 
> Obviously some testing is called for here.  I will make an attempt to do
> that testing

I've done that testing - I have an OLPC B3 unit running V2 of the
tasklet->workqueue patch, and all seems well.  30 FPS to the display and
no dropped frames.  The tasklets/0 process is running 3-5% CPU, in case
that's interesting.  For whatever reason, I see about 3% *more* idle
time when running just mplayer than I did without the patch.

Consider my minor qualms withdrawn, there doesn't seem to be any trouble
in this area.

Thanks,

jon

Jonathan Corbet / LWN.net / corbet@lwn.net
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/