Subject: Re: [PATCH 6/6] futex: fix miss ordered wakeups
From: Daniel Walker <dwalker@mvista.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>
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Date: Wed, 25 Jun 2008 08:25:07 -0700
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On Wed, 2008-06-25 at 17:07 +0200, Peter Zijlstra wrote:
> On Wed, 2008-06-25 at 07:36 -0700, Daniel Walker wrote:
> > On Wed, 2008-06-25 at 07:29 +0200, Peter Zijlstra wrote:
> > 
> > > Daniel, I'm not sure what to think,.. you were told how broken this
> > > approach was, you were told to give proper justification for this
> > > change. You did neither and just reposted the same old broken shite
> > > again.
> > 
> > Broken approach ? Never heard that before, 
> 
> I suggest you re-read some of Thomas' emails from last time...
> 
>   http://lkml.org/lkml/2008/6/12/275

Most of what he's saying there is that it breaks real time, and I
provided a real time fix in this set of patches. I don't have a problem
with the state mixing, since 99.9% of the time we're dealing operations
that don't interact (and it's perfectly ok when they do interact).

> > in fact the problem is
> > whether or not the changes are needed (not weather their broken).. I
> > gave justification in the last thread, and I'm not sure why it's unclear
> > to you..
> 
> You failed to convince, also justification goes in the changelog, not in
> random lkml threads.

It boils down to POSIX compliance which was discussed in the last
thread. POSIX requires the waiters to be sorts for 5-10 different API's
which ultimately use the futex (most of which aren't at all related to
PI).

And yes I can add it to the headers, before it goes up stream.

Daniel

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