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Message-ID: <4642CCEB.6010908@gmail.com>
Date: Thu, 10 May 2007 15:42:35 +0800
From: Li Yu <raise.sail@gmail.com>
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To: Steven Rostedt <srostedt@redhat.com>
CC: LKML <linux-kernel@vger.kernel.org>
Subject: Hi, I have one question about rt_mutex.
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Hi, Steven.

Nice to meet you again.

I have read the rt-mutex-design.txt that you wrote. That is excellent
description of rt_mutex. But I have a question for rt_mutex.

As you said:


> Now since mutexes can be defined by user-land applications, we don't
want a DOS
> type of application that nests large amounts of mutexes to create a large
> PI chain, and have the code holding spin locks while looking at a large
> amount of data. So to prevent this, the implementation not only implements
> a maximum lock depth, but also only holds at most two different locks at a
> time, as it walks the PI chain. More about this below.

After read the implementation of rt_mutex_adjust_prio_chain(), I found
the we really require maximin lock depth (1024 default), but I can not
see the check for more same locks duplication. Does this doc is
inconsistent with code?

Thanks in advanced.

Good luck.
- Li Yu
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