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Date: Wed, 2 Mar 2016 20:26:59 +0800
From: Xishi Qiu <qiuxishi@huawei.com>
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To: LKML <linux-kernel@vger.kernel.org>, Linux MM <linux-mm@kvack.org>
Subject: a question about slub in function __slab_free()
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___slab_alloc()
	deactivate_slab()
		add_full(s, n, page);
The page will be added to full list and the frozen is 0, right?

__slab_free()
	prior = page->freelist;  // prior is NULL
	was_frozen = new.frozen;  // was_frozen is 0
	...
		/*
		 * Slab was on no list before and will be
		 * partially empty
		 * We can defer the list move and instead
		 * freeze it.
		 */
		new.frozen = 1;
	...

I don't understand why "Slab was on no list before"?

Thanks,
Xishi Qiu