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Date: Thu, 29 Sep 2005 18:55:38 +0200
From: Divacky Roman <xdivac02@stud.fit.vutbr.cz>
To: hackers@freebsd.org
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Subject: dev_lock() question
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Hi,

dev_lock() looks this way:

void
dev_lock(void)
{
	if (!mtx_initialized(&devmtx))
		mtx_init(&devmtx, "cdev", NULL, MTX_DEF);
	mtx_lock(&devmtx);
}

I wonder why is the mtx_initialized checking necessary? shouldnt explicit
initialization be sufficient?

thnx for answer

roman