linux-kernel - Re: [PATCH 08/18] 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: <20130731093802.GB4880@linux.vnet.ibm.com>
Date:	Wed, 31 Jul 2013 15:08:02 +0530
From:	Srikar Dronamraju <srikar@...ux.vnet.ibm.com>
To:	Mel Gorman <mgorman@...e.de>
Cc:	Hillf Danton <dhillf@...il.com>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	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 08/18] sched: Reschedule task on preferred NUMA node once
 selected

* Mel Gorman <mgorman@...e.de> [2013-07-31 10:07:27]:

> On Wed, Jul 17, 2013 at 09:31:05AM +0800, Hillf Danton wrote:
> > On Mon, Jul 15, 2013 at 11:20 PM, Mel Gorman <mgorman@...e.de> 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?
> > 
> 
> If the task is not allowed to run on the CPUs for that node then how
> were the NUMA hinting faults recorded?
> 

But still we could check if the task is allowed to run on a cpu before we
capture the load of the cpu. This would avoid us trying to select a cpu
whose load is low but which cannot run this task.

> -- 
> Mel Gorman
> SUSE Labs
> 

-- 
Thanks and Regards
Srikar Dronamraju

--
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/