linux-kernel - Re: [RFC Patch V1 07/30] mm: Use cpu_to_mem()/numa_mem

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: <20140711152156.GB29137@htj.dyndns.org>
Date:	Fri, 11 Jul 2014 11:21:56 -0400
From:	Tejun Heo <tj@...nel.org>
To:	Christoph Lameter <cl@...two.org>
Cc:	Jiang Liu <jiang.liu@...ux.intel.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Mel Gorman <mgorman@...e.de>,
	David Rientjes <rientjes@...gle.com>,
	Mike Galbraith <umgwanakikbuti@...il.com>,
	Peter Zijlstra <peterz@...radead.org>,
	"Rafael J . Wysocki" <rafael.j.wysocki@...el.com>,
	Vladimir Davydov <vdavydov@...allels.com>,
	Johannes Weiner <hannes@...xchg.org>,
	"Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
	Rik van Riel <riel@...hat.com>,
	Wanpeng Li <liwanp@...ux.vnet.ibm.com>,
	Zhang Yanfei <zhangyanfei@...fujitsu.com>,
	Catalin Marinas <catalin.marinas@....com>,
	Jianyu Zhan <nasa4836@...il.com>, malc <av1474@...tv.ru>,
	Joonsoo Kim <iamjoonsoo.kim@....com>,
	Fabian Frederick <fabf@...net.be>,
	Tony Luck <tony.luck@...el.com>, linux-mm@...ck.org,
	linux-hotplug@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [RFC Patch V1 07/30] mm: Use cpu_to_mem()/numa_mem_id() to
 support memoryless node

Hello,

On Fri, Jul 11, 2014 at 10:13:57AM -0500, Christoph Lameter wrote:
> Allocators typically fall back but they wont in some cases if you say
> that you want memory from a particular node. A GFP_THISNODE would force a
> failure of the alloc. In other cases it should fall back. I am not sure
> that all allocations obey these conventions though.

But, GFP_THISNODE + numa_mem_id() is identical to numa_node_id() +
nearest node with memory fallback.  Is there any case where the user
would actually want to always fail if it's on the memless node?

Even if that's the case, there's no reason to burden everyone with
this distinction.  Most users just wanna say "I'm on this node.
Please allocate considering that".  There's nothing wrong with using
numa_node_id() for that.

Thanks.

-- 
tejun
--
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/