From owner-freebsd-alpha  Thu Feb  7 16:22:45 2002
Delivered-To: freebsd-alpha@freebsd.org
Received: from net2.gendyn.com (nat2.gendyn.com [204.60.171.12])
	by hub.freebsd.org (Postfix) with ESMTP id A8ADD37B41C
	for <alpha@freebsd.org>; Thu,  7 Feb 2002 16:22:37 -0800 (PST)
Received: from [153.11.11.3] (helo=plunger.gdeb.com)
	by net2.gendyn.com with esmtp (Exim 2.12 #1)
	id 16Yyo9-000M3Q-00
	for alpha@FreeBSD.org; Thu, 7 Feb 2002 19:22:29 -0500
Received: from clcrtr.gdeb.com ([153.11.109.11])
	by plunger.gdeb.com  with SMTP id TAA11556;
	Thu, 7 Feb 2002 19:19:05 -0500 (EST)
Received: from vigrid.com (gpz.clc.gdeb.com [192.168.3.12])
	by clcrtr.gdeb.com (8.11.4/8.11.4) with ESMTP id g180YcK58267;
	Thu, 7 Feb 2002 19:34:46 -0500 (EST)
	(envelope-from eischen@vigrid.com)
Message-ID: <3C631A1B.68E59BFE@vigrid.com>
Date: Thu, 07 Feb 2002 19:21:47 -0500
From: Daniel Eischen <eischen@vigrid.com>
X-Mailer: Mozilla 4.78 [en] (X11; U; SunOS 5.8 sun4u)
X-Accept-Language: en
MIME-Version: 1.0
To: alpha@FreeBSD.org
Cc: Bernd Walter <ticso@cicely8.cicely.de>
Subject: Tester needed
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Sender: owner-freebsd-alpha@FreeBSD.ORG
Precedence: bulk
List-ID: <freebsd-alpha.FreeBSD.ORG>
List-Archive: <http://docs.freebsd.org/mail/> (Web Archive)
List-Help: <mailto:majordomo@FreeBSD.ORG?subject=help> (List Instructions)
List-Subscribe: <mailto:majordomo@FreeBSD.ORG?subject=subscribe%20freebsd-alpha>
List-Unsubscribe: <mailto:majordomo@FreeBSD.ORG?subject=unsubscribe%20freebsd-alpha>
X-Loop: FreeBSD.org

I want to add the getsetcontext system call and am looking for an
alpha tester to see if the code works.  Diffs and a test program
are at:

  http://people.freebsd.org/~deischen/ucontext/uc-sys.diffs
  http://people.freebsd.org/~deischen/ucontext/uc-libc.diffs
  http://people.freebsd.org/~deischen/ucontext/test_context.c

Don't forget to regenerate the system calls before building
a kernel.

I've also got a question.  Is the user stack stored in the PCB
or does it have to be read from the PAL?  If 'td' is the current
thread, then how do we get and set the user stack?
From uc-sys.diffs:

  +void
  +get_mcontext(struct thread *td, mcontext_t *mcp)
  +{
  +
  +	/*
  +	 * Use a trapframe for getsetcontext, so just copy the
  +	 * threads trapframe.
  +	 *
  +	 * XXX - Is there something that is missing from the saved
  +	 *       trapframe?  Like the stack pointer?
  +	 */
  +	bcopy(&td->td_frame, &mcp->mc_regs, sizeof(td->td_frame));
  +#if 1
  +	mcp->mc_regs[FRAME_SP] = alpha_pal_rdusp();
  +#else
  +	mcp->mc_regs[FRAME_SP] = td->td_pcb->pcb_hw.apcb_usp;
  +#endif
  [...]

And what if 'td' is not 'curthread'?  Has it been saved in the
PCB then?  Should the above be:

  +	if (td == curthread)
  +		mcp->mc_regs[FRAME_SP] = alpha_pal_rdusp();
  +	else
  +		mcp->mc_regs[FRAME_SP] = td->td_pcb->pcb_hw.apcb_usp;


Thanks,

-- 
Dan Eischen

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-alpha" in the body of the message