From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f49.google.com (mail-pa0-f49.google.com [209.85.220.49]) by kanga.kvack.org (Postfix) with ESMTP id 451986B00BA for ; Wed, 27 May 2015 12:08:49 -0400 (EDT) Received: by pacwv17 with SMTP id wv17so1181209pac.2 for ; Wed, 27 May 2015 09:08:49 -0700 (PDT) Received: from mail-pa0-x22c.google.com (mail-pa0-x22c.google.com. [2607:f8b0:400e:c03::22c]) by mx.google.com with ESMTPS id od15si12976184pdb.221.2015.05.27.09.08.48 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 27 May 2015 09:08:48 -0700 (PDT) Received: by pabru16 with SMTP id ru16so1178884pab.1 for ; Wed, 27 May 2015 09:08:48 -0700 (PDT) Subject: Re: [RFC PATCH 2/2] arm64: Implement vmalloc based thread_info allocator Mime-Version: 1.0 (Apple Message framework v1283) Content-Type: text/plain; charset=us-ascii From: Jungseok Lee In-Reply-To: <20150527041015.GB11609@blaptop> Date: Thu, 28 May 2015 01:08:43 +0900 Content-Transfer-Encoding: quoted-printable Message-Id: References: <1432483340-23157-1-git-send-email-jungseoklee85@gmail.com> <20150525144045.GE14922@blaptop> <20150527041015.GB11609@blaptop> Sender: owner-linux-mm@kvack.org List-ID: To: Minchan Kim Cc: linux-arm-kernel@lists.infradead.org, barami97@gmail.com, Catalin Marinas , Will Deacon , linux-kernel@vger.kernel.org, linux-mm@kvack.org On May 27, 2015, at 1:10 PM, Minchan Kim wrote: > Hello Jungseok, Hi, Minchan, > On Tue, May 26, 2015 at 08:29:59PM +0900, Jungseok Lee wrote: >> On May 25, 2015, at 11:40 PM, Minchan Kim wrote: >>> Hello Jungseok, >>=20 >> Hi, Minchan, >>=20 >>> On Mon, May 25, 2015 at 01:02:20AM +0900, Jungseok Lee wrote: >>>> Fork-routine sometimes fails to get a physically contiguous region = for >>>> thread_info on 4KB page system although free memory is enough. That = is, >>>> a physically contiguous region, which is currently 16KB, is not = available >>>> since system memory is fragmented. >>>=20 >>> Order less than PAGE_ALLOC_COSTLY_ORDER should not fail in current >>> mm implementation. If you saw the order-2,3 high-order allocation = fail >>> maybe your application received SIGKILL by someone. LMK? >>=20 >> Exactly right. The allocation is failed via the following path. >>=20 >> if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL)) >> goto nopage; >>=20 >> IMHO, a reclaim operation would be not needed in this context if = memory is >> allocated from vmalloc space. It means there is no need to traverse = shrinker list.=20 >=20 > For making fork successful with using vmalloc, it's bandaid. Thanks for clarification! Best Regards Jungseok Lee= -- 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