From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=BAYES_00,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0F7C6C433ED for ; Mon, 19 Apr 2021 22:54:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DDA496135F for ; Mon, 19 Apr 2021 22:54:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230427AbhDSWyr (ORCPT ); Mon, 19 Apr 2021 18:54:47 -0400 Received: from mail-io1-f50.google.com ([209.85.166.50]:33289 "EHLO mail-io1-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230126AbhDSWyo (ORCPT ); Mon, 19 Apr 2021 18:54:44 -0400 Received: by mail-io1-f50.google.com with SMTP id a11so34456609ioo.0 for ; Mon, 19 Apr 2021 15:54:14 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=2xNe1AI+zAlQJlHonsRA7VbAthmGAmqlvMIkGNsV22k=; b=O09TIma8F+pRNckWT49pRMJZ6WRlJWw0aqUF6B9qDj6I0JyOEyZ4EYQKZ51vsbjzWL +ljejwelNhfWfLXmfgGq3MyalVPaMWExJkB6X+mXqBAOPdyiIVE7sLERuA7wj1yDy+Gd 2UEZ/1Gi8Fobn8OEXLmIkHsluLzvCbjH/qtc7tQEA7lLivDF4a5padkAtvAC0tvJuI+I SkK1dR1mL0U2fVwyhVV1xOLjDbHYe5wZDJRAizWWQRpDcKzYgD9CoFEJ/kc+2s/FKxX6 xEnkEaWTXERIC0aWebZk65/6KGo+nlvhi3tcOr7lWU7W4tdadNCJm9S4Yz2OvoLEVmGQ kUGA== X-Gm-Message-State: AOAM530KvzHfzsZ/Cjet3MmgyvPofX8EXY7HAeq1H7N1hlDC51C2Zt2l l+OYotJyJhdrSDDoinRrXXMcxO/BFIc= X-Google-Smtp-Source: ABdhPJxt5t6ZO16155uYGSei0G9muX0BqwWOt5nj2Dvznm46xkm1D5FXFelC0mcW7xv+XUHpwOdggA== X-Received: by 2002:a05:6602:1689:: with SMTP id s9mr16042508iow.171.1618872854077; Mon, 19 Apr 2021 15:54:14 -0700 (PDT) Received: from google.com (243.199.238.35.bc.googleusercontent.com. [35.238.199.243]) by smtp.gmail.com with ESMTPSA id k1sm3841824ils.54.2021.04.19.15.54.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 Apr 2021 15:54:13 -0700 (PDT) Date: Mon, 19 Apr 2021 22:54:12 +0000 From: Dennis Zhou To: Tejun Heo , Christoph Lameter , Roman Gushchin Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 0/4] percpu: partial chunk depopulation Message-ID: References: <20210419225047.3415425-1-dennis@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210419225047.3415425-1-dennis@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Apr 19, 2021 at 10:50:43PM +0000, Dennis Zhou wrote: > Hello, > > This series is a continuation of Roman's series in [1]. It aims to solve > chunks holding onto free pages by adding a reclaim process to the percpu > balance work item. > And I forgot to link [1]... [1] https://lore.kernel.org/lkml/20210408035736.883861-1-guro@fb.com/ > The main difference is that the nr_empty_pop_pages is now managed at > time of isolation instead of intermixed. This helps with deciding which > chunks to free instead of having to interleave returning chunks to > active duty. > > The allocation priority is as follows: > 1) appropriate chunk slot increasing until fit > 2) sidelined chunks > 3) full free chunks > > The last slot for to_depopulate is never used for allocations. > > A big thanks to Roman for initiating the work and being available for > iterating on these ideas. > > This patchset contains the following 4 patches: > 0001-percpu-factor-out-pcpu_check_block_hint.patch > 0002-percpu-use-pcpu_free_slot-instead-of-pcpu_nr_slots-1.patch > 0003-percpu-implement-partial-chunk-depopulation.patch > 0004-percpu-use-reclaim-threshold-instead-of-running-for-.patch > > 0001 and 0002 are clean ups. 0003 implement partial chunk depopulation > initially from Roman. 0004 adds a reclaim threshold so we do not need to > schedule for every page freed. > > This series is on top of percpu$for-5.14 67c2669d69fb. > > diffstats below: > > Dennis Zhou (2): > percpu: use pcpu_free_slot instead of pcpu_nr_slots - 1 > percpu: use reclaim threshold instead of running for every page > > Roman Gushchin (2): > percpu: factor out pcpu_check_block_hint() > percpu: implement partial chunk depopulation > > mm/percpu-internal.h | 5 + > mm/percpu-km.c | 5 + > mm/percpu-stats.c | 20 ++-- > mm/percpu-vm.c | 30 ++++++ > mm/percpu.c | 252 ++++++++++++++++++++++++++++++++++++++----- > 5 files changed, 278 insertions(+), 34 deletions(-) > > Thanks, > Dennis