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Date: Thu, 15 Jan 2009 09:10:25 +0100
From: Luigi Rizzo <rizzo@iet.unipi.it>
To: geom@freebsd.org, Luigi Rizzo <rizzo@iet.unipi.it>
Message-ID: <20090115081025.GA76218@onelab2.iet.unipi.it>
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Subject: recursion check in 'taste' functions ?
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Hi,
I notice that the check to prevent recursion in the 'taste'
function is always based on a string comparison, written
in various forms, e.g.,

	if (strcmp(pp->geom->class->name, mp->name) == 0)
                return (NULL);
	...
	if (!strcmp(pp->geom->class->name, MBR_CLASS_NAME))
                return (NULL);

Wouldn't the following be more efficient (and perhaps correct) ?

	if (pp->geom->class == mp)
		return (NULL);


This is because pp->geom->class is always initialized with a pointer
to the class descriptor, and I guess it cannot be different...

	cheers
	luigi