From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754790AbZLBPYr (ORCPT ); Wed, 2 Dec 2009 10:24:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754633AbZLBPYq (ORCPT ); Wed, 2 Dec 2009 10:24:46 -0500 Received: from e38.co.us.ibm.com ([32.97.110.159]:58495 "EHLO e38.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754415AbZLBPYo (ORCPT ); Wed, 2 Dec 2009 10:24:44 -0500 Subject: Re: [PATCH] hugetlb: Abort a hugepage pool resize if a signal is pending From: Dave Hansen To: Mel Gorman Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org In-Reply-To: <20091202141504.GE1457@csn.ul.ie> References: <20091202141504.GE1457@csn.ul.ie> Content-Type: text/plain Date: Wed, 02 Dec 2009 07:24:35 -0800 Message-Id: <1259767475.24696.2368.camel@nimitz> Mime-Version: 1.0 X-Mailer: Evolution 2.26.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2009-12-02 at 14:15 +0000, Mel Gorman wrote: > If a user asks for a hugepage pool resize but specified a large number, the > machine can begin trashing. In response, they might hit ctrl-c but signals > are ignored and the pool resize continues until it fails an allocation. This > can take a considerable amount of time so this patch aborts a pool resize > if a signal is pending. > > [dave@linux.vnet.ibm.com: His idea] > Signed-off-by: Mel Gorman > --- > mm/hugetlb.c | 3 +++ > 1 files changed, 3 insertions(+), 0 deletions(-) > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index af02ee8..a952cb8 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -1238,6 +1238,9 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count) > if (!ret) > goto out; > > + /* Bail for signals. Probably ctrl-c from user */ > + if (signal_pending(current)) > + goto out; Thanks, Mel! This will help m unwedge my system the next time I fat-finger an extra zero or two into my hugepage pool size. -- Dave