linux-kernel - Re: [RFC PATCH v4 06/40] mm: Demarcate and maintain pageblocks in region-order in the zones' freelists

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <5267F4CA.3070106@linux.vnet.ibm.com>
Date:	Wed, 23 Oct 2013 21:39:46 +0530
From:	"Srivatsa S. Bhat" <srivatsa.bhat@...ux.vnet.ibm.com>
To:	Johannes Weiner <hannes@...xchg.org>
CC:	akpm@...ux-foundation.org, mgorman@...e.de, dave@...1.net,
	tony.luck@...el.com, matthew.garrett@...ula.com, riel@...hat.com,
	arjan@...ux.intel.com, srinivas.pandruvada@...ux.intel.com,
	willy@...ux.intel.com, kamezawa.hiroyu@...fujitsu.com,
	lenb@...nel.org, rjw@...k.pl, gargankita@...il.com,
	paulmck@...ux.vnet.ibm.com, svaidy@...ux.vnet.ibm.com,
	andi@...stfloor.org, isimatu.yasuaki@...fujitsu.com,
	santosh.shilimkar@...com, kosaki.motohiro@...il.com,
	linux-pm@...r.kernel.org, linux-mm@...ck.org,
	linux-kernel@...r.kernel.org, mark.gross@...el.com
Subject: Re: [RFC PATCH v4 06/40] mm: Demarcate and maintain pageblocks in
 region-order in the zones' freelists

On 10/23/2013 03:47 PM, Johannes Weiner wrote:
> On Thu, Sep 26, 2013 at 04:44:56AM +0530, Srivatsa S. Bhat wrote:
>> --- a/mm/page_alloc.c
>> +++ b/mm/page_alloc.c
>> @@ -517,6 +517,111 @@ static inline int page_is_buddy(struct page *page, struct page *buddy,
>>  	return 0;
>>  }
>>  
>> +static void add_to_freelist(struct page *page, struct free_list *free_list)
>> +{
>> +	struct list_head *prev_region_list, *lru;
>> +	struct mem_region_list *region;
>> +	int region_id, i;
>> +
>> +	lru = &page->lru;
>> +	region_id = page_zone_region_id(page);
>> +
>> +	region = &free_list->mr_list[region_id];
>> +	region->nr_free++;
>> +
>> +	if (region->page_block) {
>> +		list_add_tail(lru, region->page_block);
>> +		return;
>> +	}
>> +
>> +#ifdef CONFIG_DEBUG_PAGEALLOC
>> +	WARN(region->nr_free != 1, "%s: nr_free is not unity\n", __func__);
>> +#endif
>> +
>> +	if (!list_empty(&free_list->list)) {
>> +		for (i = region_id - 1; i >= 0; i--) {
>> +			if (free_list->mr_list[i].page_block) {
>> +				prev_region_list =
>> +					free_list->mr_list[i].page_block;
>> +				goto out;
>> +			}
>> +		}
>> +	}
>> +
>> +	/* This is the first region, so add to the head of the list */
>> +	prev_region_list = &free_list->list;
>> +
>> +out:
>> +	list_add(lru, prev_region_list);
>> +
>> +	/* Save pointer to page block of this region */
>> +	region->page_block = lru;
> 
> "Pageblock" has a different meaning in the allocator already.
> 
> The things you string up here are just called pages, regardless of
> which order they are in and how many pages they can be split into.
> 

Ah, yes. I'll fix that.

Regards,
Srivatsa S. Bhat

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/