From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with ESMTP id C0D726B01F0 for ; Fri, 23 Apr 2010 04:45:28 -0400 (EDT) Received: from hpaq1.eem.corp.google.com (hpaq1.eem.corp.google.com [10.3.21.1]) by smtp-out.google.com with ESMTP id o3N8jQlv028766 for ; Fri, 23 Apr 2010 01:45:26 -0700 Received: from pvg4 (pvg4.prod.google.com [10.241.210.132]) by hpaq1.eem.corp.google.com with ESMTP id o3N8jJlM032485 for ; Fri, 23 Apr 2010 10:45:24 +0200 Received: by pvg4 with SMTP id 4so377166pvg.29 for ; Fri, 23 Apr 2010 01:45:22 -0700 (PDT) Date: Fri, 23 Apr 2010 01:45:17 -0700 (PDT) From: David Rientjes Subject: Re: [PATCH 1/2] mm: fix bugs of mpol_rebind_nodemask() In-Reply-To: <4BD0F797.6020704@cn.fujitsu.com> Message-ID: References: <4BD05929.8040900@cn.fujitsu.com> <4BD0F797.6020704@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Miao Xie Cc: Lee Schermerhorn , Nick Piggin , Paul Menage , Andrew Morton , Linux-Kernel , Linux-MM List-ID: On Fri, 23 Apr 2010, Miao Xie wrote: > Suppose the current mempolicy nodes is 0-2, we can remap it from 0-2 to 2, > then we can remap it from 2 to 1, but we can't remap it from 2 to 0-2. > > that is to say it can't be remaped to a large set of allowed nodes, and the task > just can use the small set of nodes for ever, even the large set of nodes is allowed, > I think it is unreasonable. > That's been the behavior for at least three years so changing it from under the applications isn't acceptable, see Documentation/vm/numa_memory_policy.txt regarding mempolicy rebinds and the two flags that are defined that can be used to adjust the behavior. The pol->v.nodes = nodes_empty(tmp) ? *nodes : tmp fix is welcome, however, as a standalone patch. -- 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