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From: cinap_lenrek@gmx.de
To: 9fans@9fans.net
Subject: Re: [9fans] devmnt crash, fix.
Date: Thu, 23 Aug 2012 11:47:14 +0200	[thread overview]
Message-ID: <ddde182808bdb363b6ed3c1501cbea21@rei2.9hal> (raw)
In-Reply-To: <2558025d29ad87b629bc88c6e6a043a3@kw.quanstro.net>

can you provide the source file, dont have current 9atom iso handy
and the stuff i found on the net doesnt seem to cut it. however,
i found http://www.quanstro.net/plan9/sleepwake.html which at the
end gives a solution to the problem:

void
dowake(Io *i)
{
	i->cond = 1;
	wakeup(i);
	i->cond = 2;		/* atomic */
	/* hands off i now */
}
void
doio(void)
{
	Io *i;

	dispatch(i = malloc(sizeof *i));
	while(waserror())
		/* eat note */;
	sleep(i, iodone, i);
	poperror();
	while(i->cond != 2)
		/* rendez not done */;
	free(i);
}

that would be relatively easy to apply to devmnt and doesnt have the
problem of spurious wakeups with abusing up->sleep as rendez.

--
cinap



  reply	other threads:[~2012-08-23  9:47 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-08-22 18:53 erik quanstrom
2012-08-22 19:09 ` cinap_lenrek
2012-08-22 19:12 ` cinap_lenrek
2012-08-22 19:53 ` cinap_lenrek
2012-08-22 22:26   ` erik quanstrom
2012-08-22 23:30 ` cinap_lenrek
2012-08-23  1:53   ` erik quanstrom
2012-08-23  9:47     ` cinap_lenrek [this message]
2012-08-23 13:27       ` erik quanstrom
2012-08-23 15:02         ` cinap_lenrek
2012-08-23 15:39         ` Bakul Shah
2012-08-23 15:48           ` erik quanstrom
2012-08-23 15:53           ` cinap_lenrek
2012-08-23 16:06             ` erik quanstrom
2012-08-23 16:18               ` cinap_lenrek
2012-08-23 16:24                 ` erik quanstrom
2012-08-23 16:47                   ` Charles Forsyth
2012-08-23 17:01                     ` cinap_lenrek
2012-08-23 17:53                     ` Bakul Shah
2012-08-23 18:03                       ` erik quanstrom
     [not found]                   ` <CAOw7k5ii5PoYZnEbDeUuhR9GsgEEGt7i+XTQm7FR9+r=ENg=xw@mail.gmail.c>
2012-08-23 17:09                     ` erik quanstrom

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