From: Chris Wedgwood <cw@f00f.org>
To: Thunder from the hill <thunder@lightweight.ods.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>,
Zheng Jian-Ming <zjm@cis.nctu.edu.tw>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: problems with changing UID/GID
Date: Tue, 27 Aug 2002 13:00:25 -0700 [thread overview]
Message-ID: <20020827200025.GA8985@tapu.f00f.org> (raw)
In-Reply-To: <Pine.LNX.4.44.0208271304250.3234-100000@hawkeye.luckynet.adm>
On Tue, Aug 27, 2002 at 01:08:04PM -0600, Thunder from the hill wrote:
And how do you protect a caller from having to wait for the lock?
You don't. If they have to wait, then they wait.
You'd need a lock count here, where you can only change the
credentials when the count is zero. But when will that ever be?
It depends... for most non-threaded applications, immediately... for
threaded applications with lots of (day) disk IO, it could be
indefinite.
And btw, the count bumping/downing does cost.
Almost immeasurable. [sg]et[eu]id doesn't get called that often.
--cw
next prev parent reply other threads:[~2002-08-27 19:56 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-08-26 13:30 problems with changing UID/GID Zheng Jian-Ming
2002-08-26 13:45 ` Alan Cox
2002-08-27 21:21 ` Mike Touloumtzis
2002-08-28 11:51 ` Florian Weimer
2002-08-28 14:01 ` Alan Cox
2002-08-26 14:58 ` Thunder from the hill
2002-08-26 17:16 ` Alan Cox
2002-08-26 17:31 ` Thunder from the hill
2002-08-26 18:47 ` Trond Myklebust
2002-08-26 18:49 ` Luca Barbieri
2002-08-27 7:54 ` Chris Wedgwood
2002-08-27 15:42 ` Thunder from the hill
2002-08-27 18:12 ` Chris Wedgwood
2002-08-27 19:08 ` Thunder from the hill
2002-08-27 20:00 ` Chris Wedgwood [this message]
2002-08-27 20:25 ` Thunder from the hill
2002-08-27 20:52 ` Chris Wedgwood
2002-08-27 19:35 ` Trond Myklebust
2002-08-27 20:01 ` Chris Wedgwood
2002-08-27 22:09 ` Trond Myklebust
2002-08-28 14:24 ` Dave McCracken
2002-08-28 18:30 ` Trond Myklebust
2002-08-28 20:59 ` Dave McCracken
2002-08-28 23:20 ` Trond Myklebust
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