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From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@9fans.net
Subject: Re: [9fans] interesting timing tests
Date: Mon, 21 Jun 2010 10:40:57 -0400	[thread overview]
Message-ID: <a4c3e91d8044dc47b504fab2bf11aa54@kw.quanstro.net> (raw)
In-Reply-To: <AANLkTimysByILLkzs6Fs5XfqxmXcQNB3tazBtgbIhHiw@mail.gmail.com>

void
lock(ulong *l)
{
	ulong old;
	ushort next, owner;

	old = _xadd(l, 1);
	for(;;){
		next = old;
		owner = old>>16;
		old = *l;
		if(next == owner)
			break;
	}
}

void
unlock(ulong *l)
{
	_xadd(l, 1<<16);
}

- erik



  reply	other threads:[~2010-06-21 14:40 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-06-18 23:26 erik quanstrom
2010-06-19 13:42 ` Richard Miller
2010-06-20  1:36   ` erik quanstrom
2010-06-20  7:44     ` Richard Miller
2010-06-20 12:45       ` erik quanstrom
2010-06-20 16:51         ` Richard Miller
2010-06-20 21:55           ` erik quanstrom
2010-06-21  1:41             ` erik quanstrom
2010-06-21  3:46               ` Venkatesh Srinivas
2010-06-21 14:40                 ` erik quanstrom [this message]
2010-06-21 16:42                   ` Venkatesh Srinivas
2010-06-21 16:43                   ` erik quanstrom
2010-06-21 21:11 ` Bakul Shah
2010-06-21 21:21   ` erik quanstrom
2010-06-21 21:47     ` Bakul Shah
2010-06-21 22:16       ` erik quanstrom
2010-06-22  3:24 ` Lawrence E. Bakst
2010-06-23  1:09   ` erik quanstrom

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