From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751231Ab3GQBbI (ORCPT ); Tue, 16 Jul 2013 21:31:08 -0400 Received: from mail-oa0-f45.google.com ([209.85.219.45]:47845 "EHLO mail-oa0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750972Ab3GQBbG (ORCPT ); Tue, 16 Jul 2013 21:31:06 -0400 MIME-Version: 1.0 In-Reply-To: <1373901620-2021-9-git-send-email-mgorman@suse.de> References: <1373901620-2021-1-git-send-email-mgorman@suse.de> <1373901620-2021-9-git-send-email-mgorman@suse.de> Date: Wed, 17 Jul 2013 09:31:05 +0800 Message-ID: Subject: Re: [PATCH 08/18] sched: Reschedule task on preferred NUMA node once selected From: Hillf Danton To: Mel Gorman Cc: Peter Zijlstra , Srikar Dronamraju , Ingo Molnar , Andrea Arcangeli , Johannes Weiner , Linux-MM , LKML Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 15, 2013 at 11:20 PM, 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); > + > + rcu_read_lock(); > + for_each_cpu(i, cpumask_of_node(nid)) { Check allowed CPUs first if task is given? > + load = weighted_cpuload(i); > + > + if (load < min_load) { > + min_load = load; > + idlest_cpu = i; > + } > + } > + rcu_read_unlock(); > + > + return idlest_cpu; > +} > + [...] > + /* > + * Record the preferred node as the node with the most faults, > + * requeue the task to be running on the idlest CPU on the > + * preferred node and reset the scanning rate to recheck > + * the working set placement. > + */ > if (max_faults && max_nid != p->numa_preferred_nid) { > + int preferred_cpu; > + > + /* > + * If the task is not on the preferred node then find the most > + * idle CPU to migrate to. > + */ > + preferred_cpu = task_cpu(p); > + if (cpu_to_node(preferred_cpu) != max_nid) { > + preferred_cpu = find_idlest_cpu_node(preferred_cpu, > + max_nid); > + } > + > + /* Update the preferred nid and migrate task if possible */ > p->numa_preferred_nid = max_nid; > p->numa_migrate_seq = 0; > + migrate_task_to(p, preferred_cpu); > } From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx147.postini.com [74.125.245.147]) by kanga.kvack.org (Postfix) with SMTP id 625766B0033 for ; Tue, 16 Jul 2013 21:31:06 -0400 (EDT) Received: by mail-oa0-f50.google.com with SMTP id k7so1778298oag.9 for ; Tue, 16 Jul 2013 18:31:05 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <1373901620-2021-9-git-send-email-mgorman@suse.de> References: <1373901620-2021-1-git-send-email-mgorman@suse.de> <1373901620-2021-9-git-send-email-mgorman@suse.de> Date: Wed, 17 Jul 2013 09:31:05 +0800 Message-ID: Subject: Re: [PATCH 08/18] sched: Reschedule task on preferred NUMA node once selected From: Hillf Danton Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Peter Zijlstra , Srikar Dronamraju , Ingo Molnar , Andrea Arcangeli , Johannes Weiner , Linux-MM , LKML On Mon, Jul 15, 2013 at 11:20 PM, 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); > + > + rcu_read_lock(); > + for_each_cpu(i, cpumask_of_node(nid)) { Check allowed CPUs first if task is given? > + load = weighted_cpuload(i); > + > + if (load < min_load) { > + min_load = load; > + idlest_cpu = i; > + } > + } > + rcu_read_unlock(); > + > + return idlest_cpu; > +} > + [...] > + /* > + * Record the preferred node as the node with the most faults, > + * requeue the task to be running on the idlest CPU on the > + * preferred node and reset the scanning rate to recheck > + * the working set placement. > + */ > if (max_faults && max_nid != p->numa_preferred_nid) { > + int preferred_cpu; > + > + /* > + * If the task is not on the preferred node then find the most > + * idle CPU to migrate to. > + */ > + preferred_cpu = task_cpu(p); > + if (cpu_to_node(preferred_cpu) != max_nid) { > + preferred_cpu = find_idlest_cpu_node(preferred_cpu, > + max_nid); > + } > + > + /* Update the preferred nid and migrate task if possible */ > p->numa_preferred_nid = max_nid; > p->numa_migrate_seq = 0; > + migrate_task_to(p, preferred_cpu); > } -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org