Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753889AbcJ0QbP (ORCPT ); Thu, 27 Oct 2016 12:31:15 -0400 Received: from mail-lf0-f66.google.com ([209.85.215.66]:35722 "EHLO mail-lf0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751613AbcJ0QbK (ORCPT ); Thu, 27 Oct 2016 12:31:10 -0400 From: Piotr Kwapulinski To: akpm@linux-foundation.org Cc: kirill.shutemov@linux.intel.com, vbabka@suse.cz, rientjes@google.com, mhocko@suse.com, liangchen.linux@gmail.com, mgorman@techsingularity.net, dave.hansen@linux.intel.com, nzimmer@sgi.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, kwapulinski.piotr@gmail.com Subject: [PATCH v3 0/1] mm/mempolicy.c: forbid static or relative flags for local NUMA mode Date: Thu, 27 Oct 2016 18:30:37 +0200 Message-Id: <20161027163037.4089-1-kwapulinski.piotr@gmail.com> X-Mailer: git-send-email 2.10.0 In-Reply-To: <20160927132532.12110-1-kwapulinski.piotr@gmail.com> References: <20160927132532.12110-1-kwapulinski.piotr@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1434 Lines: 39 The MPOL_F_STATIC_NODES and MPOL_F_RELATIVE_NODES flags are irrelevant when setting them for MPOL_LOCAL NUMA memory policy via set_mempolicy or mbind. Return the "invalid argument" from set_mempolicy and mbind whenever any of these flags is passed along with MPOL_LOCAL. It is consistent with MPOL_PREFERRED passed with empty nodemask. It slightly shortens the execution time in paths where these flags are used e.g. when trying to rebind the NUMA nodes for changes in cgroups cpuset mems (mpol_rebind_preferred()) or when just printing the mempolicy structure (/proc/PID/numa_maps). Isolated tests done. Signed-off-by: Piotr Kwapulinski --- Changes since V2: Information from Documentation/vm/numa_memory_policy.txt removed. Please let me know what else I should do to let this patch to be accepted. --- mm/mempolicy.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 0b859af..266893e 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -276,7 +276,9 @@ static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags, return ERR_PTR(-EINVAL); } } else if (mode == MPOL_LOCAL) { - if (!nodes_empty(*nodes)) + if (!nodes_empty(*nodes) || + (flags & MPOL_F_STATIC_NODES) || + (flags & MPOL_F_RELATIVE_NODES)) return ERR_PTR(-EINVAL); mode = MPOL_PREFERRED; } else if (nodes_empty(*nodes)) -- 2.10.0