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Date: Sun, 02 Jan 2011 18:48:01 -0500
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To: Christoph Lameter <cl@linux-foundation.org>,
        Pekka Enberg <penberg@cs.helsinki.fi>, Matt Mackall <mpm@selenic.com>,
        linux-mm@kvack.org
cc: linux-kernel@vger.kernel.org
Subject: Should we be using unlikely() around tests of GFP_ZERO?
From: "Theodore Ts'o" <tytso@mit.edu>
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Given the patches being busily submitted by trivial patch submitters to
make use kmem_cache_zalloc(), et. al, I believe we should remove the
unlikely() tests around the (gfp_flags & __GFP_ZERO) tests, such as:

-	if (unlikely((flags & __GFP_ZERO) && objp))
+	if ((flags & __GFP_ZERO) && objp)
		memset(objp, 0, obj_size(cachep));

Agreed?  If so, I'll send a patch...

	    					- Ted