linux-kernel - Re: [PATCH 6/8] sched: Reschedule task on preferred NUMA node once selected

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: <20130627145458.GU28407@twins.programming.kicks-ass.net>
Date:	Thu, 27 Jun 2013 16:54:58 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	Mel Gorman <mgorman@...e.de>
Cc:	Ingo Molnar <mingo@...nel.org>,
	Andrea Arcangeli <aarcange@...hat.com>,
	Johannes Weiner <hannes@...xchg.org>,
	Linux-MM <linux-mm@...ck.org>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 6/8] sched: Reschedule task on preferred NUMA node once
 selected

On Wed, Jun 26, 2013 at 03:38:05PM +0100, Mel Gorman wrote:
> +static int
> +find_idlest_cpu_node(int this_cpu, int nid)
> +{
> +	unsigned long load, min_load = ULONG_MAX;
> +	int i, idlest_cpu = this_cpu;
> +
> +	BUG_ON(cpu_to_node(this_cpu) == nid);
> +
> +	for_each_cpu(i, cpumask_of_node(nid)) {
> +		load = weighted_cpuload(i);
> +
> +		if (load < min_load) {
> +			struct task_struct *p;
> +
> +			/* Do not preempt a task running on its preferred node */
> +			struct rq *rq = cpu_rq(i);
> +			local_irq_disable();
> +			raw_spin_lock(&rq->lock);

raw_spin_lock_irq() ?

> +			p = rq->curr;
> +			if (p->numa_preferred_nid != nid) {
> +				min_load = load;
> +				idlest_cpu = i;
> +			}
> +			raw_spin_unlock(&rq->lock);
> +			local_irq_disable();
> +		}
> +	}
> +
> +	return idlest_cpu;
> +}
--
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/