From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id CDA1B6B000D for ; Mon, 26 Mar 2018 11:38:38 -0400 (EDT) Received: by mail-pf0-f199.google.com with SMTP id u8so2176721pfm.21 for ; Mon, 26 Mar 2018 08:38:38 -0700 (PDT) Received: from EUR01-VE1-obe.outbound.protection.outlook.com (mail-ve1eur01on0090.outbound.protection.outlook.com. [104.47.1.90]) by mx.google.com with ESMTPS id a12-v6si16416380plt.606.2018.03.26.08.38.37 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 26 Mar 2018 08:38:37 -0700 (PDT) Subject: Re: [PATCH 01/10] mm: Assign id to every memcg-aware shrinker References: <152163840790.21546.980703278415599202.stgit@localhost.localdomain> <152163847740.21546.16821490541519326725.stgit@localhost.localdomain> <20180324184009.dyjlt4rj4b6y6sz3@esperanza> <0db2d93f-12cd-d703-fce7-4c3b8df5bc12@virtuozzo.com> <20180326151406.GE10912@bombadil.infradead.org> From: Kirill Tkhai Message-ID: Date: Mon, 26 Mar 2018 18:38:29 +0300 MIME-Version: 1.0 In-Reply-To: <20180326151406.GE10912@bombadil.infradead.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Matthew Wilcox Cc: Vladimir Davydov , viro@zeniv.linux.org.uk, hannes@cmpxchg.org, mhocko@kernel.org, akpm@linux-foundation.org, tglx@linutronix.de, pombredanne@nexb.com, stummala@codeaurora.org, gregkh@linuxfoundation.org, sfr@canb.auug.org.au, guro@fb.com, mka@chromium.org, penguin-kernel@I-love.SAKURA.ne.jp, chris@chris-wilson.co.uk, longman@redhat.com, minchan@kernel.org, hillf.zj@alibaba-inc.com, ying.huang@intel.com, mgorman@techsingularity.net, shakeelb@google.com, jbacik@fb.com, linux@roeck-us.net, linux-kernel@vger.kernel.org, linux-mm@kvack.org On 26.03.2018 18:14, Matthew Wilcox wrote: > On Mon, Mar 26, 2018 at 06:09:35PM +0300, Kirill Tkhai wrote: >>> AFAIK ida always allocates the smallest available id so you don't need >>> to keep track of bitmap_id_start. >> >> I saw mnt_alloc_group_id() does the same, so this was the reason, the additional >> variable was used. Doesn't this gives a good advise to ida and makes it find >> a free id faster? > > No, it doesn't help the IDA in the slightest. I have a patch in my > tree to delete that silliness from mnt_alloc_group_id(); just haven't > submitted it yet. Ok, then I'll remove this trick. Thanks, Kirill