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From: Nicolas Pitre <nico@fluxnic.net>
Subject: Re: [PATCH v2] Make xmalloc and xrealloc thread-safe
Date: Wed, 07 Apr 2010 10:47:01 -0400 (EDT)
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Cc: Fredrik Kuivinen <frekui@gmail.com>,
	Junio C Hamano <gitster@pobox.com>, git@vger.kernel.org,
	Johannes Sixt <j6t@kdbg.org>
To: Shawn Pearce <spearce@spearce.org>
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On Wed, 7 Apr 2010, Shawn Pearce wrote:

> On Wed, Apr 7, 2010 at 6:17 AM, Nicolas Pitre <nico@fluxnic.net> wrote:
> > Yet, the memset() issue comes up only because pthread_t is meant to be
> > an opaque type.  The only information we would need here is the actual
> > thread ID as returned by gettid() on Linux or GetCurrentThreadId() on
> > Windows, and then the read_mutex_owner could be a simple atomically
> > modifiable integer.  But what about other pthread-capable non Linux
> > systems?
> 
> Indeed.  If Windows threads are atomic words, then actually you don't
> need that double mutex in the emulation layer, and can instead use the
> atomic word to determine ownership.  Which makes this entire debate
> somewhat moot, doesn't it?

Well, indeed.


Nicolas

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