linux-kernel - Re: [PATCH 2/4 v6] lib: debugobjects: add global free list and the counter

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Message-ID: <alpine.DEB.2.21.1802121654350.1158@nanos.tec.linutronix.de>
Date:   Mon, 12 Feb 2018 16:54:58 +0100 (CET)
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Yang Shi <yang.shi@...ux.alibaba.com>
cc:     longman@...hat.com, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/4 v6] lib: debugobjects: add global free list and the
 counter

On Mon, 12 Feb 2018, Thomas Gleixner wrote:
> On Tue, 6 Feb 2018, Yang Shi wrote:
> > +	/*
> > +	 * The objs on the pool list might be allocated before the work is
> > +	 * run, so recheck if pool list it full or not, if not fill pool
> > +	 * list from the global free list
> > +	 */
> > +	while (obj_pool_free < debug_objects_pool_size) {
> > +		if (obj_nr_tofree <= 0)
> > +			break;
> > +
> > +		obj = hlist_entry(obj_to_free.first, typeof(*obj), node);
> > +		hlist_del(&obj->node);
> > +		hlist_add_head(&obj->node, &obj_pool);
> > +		obj_pool_free++;
> > +		obj_nr_tofree--;
> > +	}
> > +
> > +	/*
> > +	 * pool list is already full, and there are still objs on the free list,
> > +	 * move remaining free objs to a separate list to free the memory later.
> > +	 */
> > +	if (obj_nr_tofree > 0) {
> > +		hlist_move_list(&obj_to_free, &tofree);
> > +		obj_nr_tofree = 0;
> > +	}
> > +
> >  	while (obj_pool_free >= debug_objects_pool_size + ODEBUG_FREE_BATCH) {
> >  		for (i = 0; i < ODEBUG_FREE_BATCH; i++) {
> >  			objs[i] = hlist_entry(obj_pool.first,
> 
> This whole section is now pointless and can be removed. There is no way
> that this code path can be entered after this change. Surplus objects are
> on the obj_to_free list and not on the obj_pool itself.

Actually not in this patch, but in the next one.

Thanks,

	tglx