Date: Wed, 26 Mar 2008 11:37:47 -0400 (EDT)
From: Alan Stern <stern@rowland.harvard.edu>
To: Richard Kennedy <richard@rsk.demon.co.uk>
cc: dbrownell@users.sourceforge.net, linux-usb <linux-usb@vger.kernel.org>,
       lkml <linux-kernel@vger.kernel.org>
Subject: Re: ohci : strange looking use of round_jiffies_relative. possible
 bug ?
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On Wed, 26 Mar 2008, Richard Kennedy wrote:

> I was looking at the uses of round_jiffies and noticed that the ohci
> unlink_watchdog_func() calls 
> mod_timer(&ohci->unlink_watchdog, round_jiffies_relative(HZ));
> 
> Which looks a bit strange as it will set the timer to 0 <= t < HZ.
> Reading the comments I think that is really is expecting to setup timer
> to (now + 1s)
> 
> mod_timer(&ohci->unlink_watchdog, round_jiffies(jiffies + HZ));
> 
> If this is not true then perhaps it needs a comment to explain what it
> _is_ trying to do, because it's got me baffled ;)

I'd say it's a bug.  Or rather a pair of bugs, since that mod_timer() 
call appears in two places.

Alan Stern

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