From owner-freebsd-mips@FreeBSD.ORG  Tue Dec 28 17:22:32 2010
Return-Path: <owner-freebsd-mips@FreeBSD.ORG>
Delivered-To: freebsd-mips@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 76BC21065670
	for <freebsd-mips@freebsd.org>; Tue, 28 Dec 2010 17:22:32 +0000 (UTC)
	(envelope-from imp@bsdimp.com)
Received: from harmony.bsdimp.com (bsdimp.com [199.45.160.85])
	by mx1.freebsd.org (Postfix) with ESMTP id 35BDC8FC08
	for <freebsd-mips@freebsd.org>; Tue, 28 Dec 2010 17:22:32 +0000 (UTC)
Received: from [127.0.0.1] (localhost [127.0.0.1])
	by harmony.bsdimp.com (8.14.3/8.14.1) with ESMTP id oBSHGp9p056985
	for <freebsd-mips@freebsd.org>; Tue, 28 Dec 2010 10:16:52 -0700 (MST)
	(envelope-from imp@bsdimp.com)
Message-ID: <4D1A1B83.5070602@bsdimp.com>
Date: Tue, 28 Dec 2010 10:16:51 -0700
From: Warner Losh <imp@bsdimp.com>
User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US;
	rv:1.9.2.12) Gecko/20101029 Thunderbird/3.1.6
MIME-Version: 1.0
To: freebsd-mips@freebsd.org
References: <AANLkTimg3CUk0p8YPyepiumEHvKo2F6jdVA0=1CefYrQ@mail.gmail.com>	<AANLkTikxHUj+Ge3YyJOWMQne31D=uY_712Qveq=Dmh2A@mail.gmail.com>	<AANLkTimyqAWFo5Ddd8_UAL654iGquCMnEjFETUnsFdxO@mail.gmail.com>
	<AANLkTi=nyXw3Tw-BnhAMwob4yP0-TSxeh5f_wEjtEfQ9@mail.gmail.com>
In-Reply-To: <AANLkTi=nyXw3Tw-BnhAMwob4yP0-TSxeh5f_wEjtEfQ9@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Subject: Re: [PATCH] Retrieval of TLS pointer via RDHWR
X-BeenThere: freebsd-mips@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Porting FreeBSD to MIPS <freebsd-mips.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-mips>,
	<mailto:freebsd-mips-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-mips>
List-Post: <mailto:freebsd-mips@freebsd.org>
List-Help: <mailto:freebsd-mips-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-mips>,
	<mailto:freebsd-mips-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 28 Dec 2010 17:22:32 -0000

On 12/28/2010 04:36, Robert Millan wrote:
> Not interested?
>
> Note this might become mandatory if you ever want to compile
> code that uses TLS with recent GCC.
>
> In any case, when executed natively, rdhwr is a speed-up
> compared to a sysarch() call.
Actually, am interested in this, but have been swamped with other 
things...  The code looks good, and we should definitely move in this 
direction.

Warner
> 2010/12/9 Robert Millan<rmh@debian.org>:
>> 2010/12/9 Jayachandran C.<jchandra@freebsd.org>:
>>> I'm not sure that the freebsd mips toolchain supports the __thread
>>> directive yet.  Were you able to test this from C?
>> Yes, but not via __thread.  I wrote a small program that sets
>> the TLS pointer to an arbitrary value (via MIPS_SET_TLS),
>> then issued rdhwr instruction using C inline assembly, and
>> finally verified that both values are the same.
>>
>> (the toolchain I'm using doesn't support __thread either,
>> but I submit this patch with the expectation that it can be
>> useful later on)
>>
>> --
>> Robert Millan
>>
>
>