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

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Date:   Mon, 12 Feb 2018 10:53:24 -0800
From:   Yang Shi <yang.shi@...ux.alibaba.com>
To:     Thomas Gleixner <tglx@...utronix.de>
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 2/12/18 7:54 AM, Thomas Gleixner wrote:
> 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.

Yes, it is correct. I think the whole ODEBUG_FREE_BATCH thing can be 
removed too.

Will do it in the next version.

Regards,
Yang

> Actually not in this patch, but in the next one.
>
> Thanks,
>
> 	tglx