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Date: Wed, 14 Nov 2007 12:35:13 +0800
From: Jerry Jiang <wjiang@resilience.com>
To: linux-kernel@vger.kernel.org
Subject: [LOCK] Is it really necessary to use a "big module lock"?
Message-Id: <20071114123513.fbff2683.wjiang@resilience.com>
Organization: Resilience
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Hi all,

I came across a question when review other's module code.

something like:

int __init module_init()
{
	down_interruptible(the_big_module_sem);
	// code for init...
	up(the_big_module_sem);
}

void __exit module_exit()
{
	down_interruptible(the_big_module_sem);
	// code for exit...
	up(the_big_module_sem);
}

My question is:
 - Is the lock truly necessary?
 - If adding it into code, what happens?

Thank you
-- Jerry