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Date: Mon, 19 Jan 2009 19:41:35 -0500
From: Brian Fundakowski Feldman <green@FreeBSD.org>
To: Jason Evans <jasone@FreeBSD.org>
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Cc: hackers@FreeBSD.org, Julian Elischer <julian@elischer.org>
Subject: Re: threaded, forked, rethreaded processes will deadlock
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On Fri, Jan 16, 2009 at 02:36:06PM -0800, Jason Evans wrote:
> Brian Fundakowski Feldman wrote:
>  > Could you, and anyone else who would care to, check this out?  It's a 
> regression
>> fix but it also makes the code a little bit clearer.  Thanks!
>> 
>> Index: lib/libc/stdlib/malloc.c
> 
> Why does malloc need to change for this?  Unless there's a really good 
> reason, I don't want the extra branches in the locking functions.

Because malloc is the thing causing the regression.  It is easy enough
to optimize out the one extra fetch and branch in the single-threaded case
if I can get some consensus that the fix to it is actually fine.

-- 
Brian Fundakowski Feldman                           \'[ FreeBSD ]''''''''''\
  <> green@FreeBSD.org                               \  The Power to Serve! \
 Opinions expressed are my own.                       \,,,,,,,,,,,,,,,,,,,,,,\