linux-kernel - Re: [PATCH 26/35] Use the per-cpu allocator for orders up to PAGE_ALLOC_COSTLY

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]

Date:	Mon, 16 Mar 2009 12:26:07 -0400 (EDT)
From:	Christoph Lameter <cl@...ux-foundation.org>
To:	Mel Gorman <mel@....ul.ie>
cc:	Linux Memory Management List <linux-mm@...ck.org>,
	Pekka Enberg <penberg@...helsinki.fi>,
	Rik van Riel <riel@...hat.com>,
	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	Johannes Weiner <hannes@...xchg.org>,
	Nick Piggin <npiggin@...e.de>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Lin Ming <ming.m.lin@...el.com>,
	Zhang Yanmin <yanmin_zhang@...ux.intel.com>,
	Peter Zijlstra <peterz@...radead.org>
Subject: Re: [PATCH 26/35] Use the per-cpu allocator for orders up to
 PAGE_ALLOC_COSTLY_ORDER

On Mon, 16 Mar 2009, Mel Gorman wrote:

> -static void free_hot_cold_page(struct page *page, int cold)
> +static void free_hot_cold_page(struct page *page, int order, int cold)
>  {
>  	struct zone *zone = page_zone(page);
>  	struct per_cpu_pages *pcp;
>  	unsigned long flags;
>  	int clearMlocked = PageMlocked(page);
>
> +	/* SLUB can return lowish-order compound pages that need handling */
> +	if (order > 0 && unlikely(PageCompound(page)))
> +		if (unlikely(destroy_compound_page(page, order)))
> +			return;
> +

Isnt that also true for stacks and generic network objects ==- 8k?

>  again:
>  	cpu  = get_cpu();
> -	if (likely(order == 0)) {
> +	if (likely(order <= PAGE_ALLOC_COSTLY_ORDER)) {
>  		struct per_cpu_pages *pcp;
> +		int batch;
> +		int delta;
>
>  		pcp = &zone_pcp(zone, cpu)->pcp;
> +		batch = max(1, pcp->batch >> order);
>  		local_irq_save(flags);
>  		if (!pcp->count) {
> -			pcp->count = rmqueue_bulk(zone, 0,
> -					pcp->batch, &pcp->list, migratetype);
> +			delta = rmqueue_bulk(zone, order, batch,
> +					&pcp->list, migratetype);
> +			bulk_add_pcp_page(pcp, order, delta);
>  			if (unlikely(!pcp->count))
>  				goto failed;

The pcp adds a series of order N pages if an order N alloc occurs and the
queue is empty?

--
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/