[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: a recursive lock prototype

From: Thomas Bushnell, BSG
Subject: Re: a recursive lock prototype
Date: 05 Jul 2001 08:57:15 -0700
User-agent: Gnus/5.0808 (Gnus v5.8.8) Emacs/20.7

Marcus Brinkmann <brinkmd@master.debian.org> writes:

> We agreed, in an inspiring coordinated coding effort, on the following
> implementation (thanks to Johannes, Neal, Moshe and Rene):

No, that still has a race condition as follows.  We begin in the fully
unlocked state.

THREAD 1                        THREAD 2

Start recursive_lock
Read RL->locking_thread
                Context Switch
                                Start recursive_lock, function finishes        
                Context Switch
Check RL->locking_thread
  it seems to match, and the lock
  incorrectly succeeds.

You need some kind of guard around this structure!

reply via email to

[Prev in Thread] Current Thread [Next in Thread]