Received: by 2002:a05:7412:8d10:b0:f3:1519:9f41 with SMTP id bj16csp5308875rdb; Wed, 13 Dec 2023 05:21:23 -0800 (PST) X-Google-Smtp-Source: AGHT+IFOpzITgzyIAErkHRvKTc11AruVQ3iQ7UQ2etdVlmfm9PLuTDZUsINiVvPXTGDXGcwME5KX X-Received: by 2002:a17:902:eb86:b0:1d0:92a0:492a with SMTP id q6-20020a170902eb8600b001d092a0492amr4664611plg.85.1702473683176; Wed, 13 Dec 2023 05:21:23 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1702473683; cv=none; d=google.com; s=arc-20160816; b=0QBU0QRIKdrdK026yF/vh9NRpil8MXGzgUkR4FAwrtVKbQqmVycwQuXFrtqXrj60at duL+O62taimjORU8/R46Rc/RO1GHZ9ZKfBlXHeLuTYEM6p5ZbjXq9lCD49++tIrDSZhL 8S8KUpAqEgKxppmv+YQeT5Mg8KNmhhLk1cOrT8cmjGOSwGB8JrMVO4GUlGKb4ZGsjk6/ Kqs3u0RgNJAyJhZOPibuf0hNkdI5vdMe0YRgucASGqfz7bWrJplTykigEhOMMou/Fv2f XmhkjBegdq/arMw0K5MAVJLIhU5BzGqu7DOoUfgc8AIB99/70KD1/cd16VYxrcHxrveL Z10w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:cc:to:subject :message-id:date:from:in-reply-to:references:mime-version :dkim-signature; bh=7hnDLGznNjf0HtUhZB6DiqmuEaPkDCvG/kcvfPciErs=; fh=6yEqBb9DWJhifLHlkqaL4I56FZSAMUnpEkreom+8ieA=; b=tNvGhxJrVZqDN+NYa6W3s9HiJGbcmwWybZnUOBZ4VDPhsE3lo8CY+aztN6ZFETiitc fZtr2MgeTa0qnxw3QQbHSJOBQwbmdKehXQRAGjns/tsSHH8fy3ybVR16BfNike4LYOQ5 fwYefLn7a1bQbbYdnmRVyf3NfAAZ0bseikuVrE1MZZ2felK71L8cEq1M6TtXbIYo6H7C Q4Ek1Ktbv+3dyDPnFAv2KwGOqi+TELf9xAbKuMaS13/ROkRl97Hv2ye/V3UUuyuBWz+z hV2GD6fJCBXuxSUxheM8bDU6gZ51LQbGGX6mUitDgqmzY/i2fZrycnA5ZOmHesfBXrdf eP6A== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20230601 header.b="HuT/CweC"; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Return-Path: Received: from lipwig.vger.email (lipwig.vger.email. [23.128.96.33]) by mx.google.com with ESMTPS id d16-20020a170902ced000b001d0bcd70814si9778983plg.294.2023.12.13.05.21.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 13 Dec 2023 05:21:23 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) client-ip=23.128.96.33; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20230601 header.b="HuT/CweC"; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by lipwig.vger.email (Postfix) with ESMTP id BC2598039FFC; Wed, 13 Dec 2023 05:21:17 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at lipwig.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1379191AbjLMNUt (ORCPT + 99 others); Wed, 13 Dec 2023 08:20:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56366 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1379207AbjLMNUl (ORCPT ); Wed, 13 Dec 2023 08:20:41 -0500 Received: from mail-wr1-x42f.google.com (mail-wr1-x42f.google.com [IPv6:2a00:1450:4864:20::42f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D19F6D5 for ; Wed, 13 Dec 2023 05:20:43 -0800 (PST) Received: by mail-wr1-x42f.google.com with SMTP id ffacd0b85a97d-3363eba94ebso382410f8f.3 for ; Wed, 13 Dec 2023 05:20:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1702473642; x=1703078442; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=7hnDLGznNjf0HtUhZB6DiqmuEaPkDCvG/kcvfPciErs=; b=HuT/CweCmS/3ati45b7FdqfhZun3kaMzOJZo9XaUk46zQzTeY4OoCIP9NQP+Y4CzSd wZHyzrq+0QQkzOFrSngEiofveXjH7qV+uHnh+E+dP89imiqIsrUYadd8QfbyvHT1s/cO TIfAZqnKK59HgEOUUPQbaGAUo6RZps5k+PqYUHP60PrxI/L/MwFH4ANnW2qaoiipRtIo WuYz+C0Ei55/ITQXpoJETdMWFhTc3ianc9dyIkJFRkKPKci+ghGEbUixh5S7atB/DLre KEK6LdqigUu3wOEtVeeiOJK7ubjcoPnzsXVOngbcBMIsAhih4t0qh/qav/6KAoT5AHeY iNJQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702473642; x=1703078442; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=7hnDLGznNjf0HtUhZB6DiqmuEaPkDCvG/kcvfPciErs=; b=JxnFyBqsx8usdB89ltp6a9deoHtlB/kzv1m129923N7VJ/nh3hzKJPIJgEDkY6q5k5 uKuXDVmjlQ3bcd0jFhoC3GAF2FTUwxp3Z1ubT4/L7z5Gq80A6Tm6qggfIy9406ALXzU3 NSP67HaGdVwB71o4c+jQF+QFPj69wAUf7pjxL+Ow6BGx0kb7hTDjsrkQAQoGprk8Fpzx aKqteRikDMuo76k3i9SHPnzp6b3NgRIj7oIF71cXCB0+7RH3Rc8YBoEL1IFt6D1FPY5w VtlHxP0ulpV+KoGY4CEhmR3c2F29meLb3Zq/LeYXfldBje9uQoFpQVZXa8vtbK74sKOt 5y2A== X-Gm-Message-State: AOJu0YwwpULqP0aWtZggzMdnldA/50cTSEtWUIwKpCND08DXFPiZmdrh ewhXeQ015M1qza2j3W9nLSmyQTpjoLTO7iEInqkws3wuEkk= X-Received: by 2002:adf:f94c:0:b0:334:bca8:4e64 with SMTP id q12-20020adff94c000000b00334bca84e64mr1484593wrr.143.1702473642020; Wed, 13 Dec 2023 05:20:42 -0800 (PST) MIME-Version: 1.0 References: <20231211052850.3513230-1-debug.penguin32@gmail.com> In-Reply-To: From: Ronald Monthero Date: Wed, 13 Dec 2023 23:20:04 +1000 Message-ID: Subject: Re: [PATCH] mm/zswap: Improve with alloc_workqueue() call To: Nhat Pham Cc: sjenning@redhat.com, akpm@linux-foundation.org, Dan Streetman , Vitaly Wool , linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-0.6 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lipwig.vger.email Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (lipwig.vger.email [0.0.0.0]); Wed, 13 Dec 2023 05:21:17 -0800 (PST) Hi Nhat, Thanks for checking. On Tue, Dec 12, 2023 at 12:16=E2=80=AFAM Nhat Pham wrot= e: > > On Sun, Dec 10, 2023 at 9:31=E2=80=AFPM Ronald Monthero > wrote: > > > > Use alloc_workqueue() to create and set finer > > work item attributes instead of create_workqueue() > > which is to be deprecated. > > > > Signed-off-by: Ronald Monthero > > --- > > mm/zswap.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/mm/zswap.c b/mm/zswap.c > > index 74411dfdad92..64dbe3e944a2 100644 > > --- a/mm/zswap.c > > +++ b/mm/zswap.c > > @@ -1620,7 +1620,8 @@ static int zswap_setup(void) > > zswap_enabled =3D false; > > } > > > > - shrink_wq =3D create_workqueue("zswap-shrink"); > > + shrink_wq =3D alloc_workqueue("zswap-shrink", > > + WQ_UNBOUND|WQ_MEM_RECLAIM, 0); > > Hmmm this changes the current behavior a bit right? create_workqueue() > is currently defined as: > > alloc_workqueue("%s", __WQ_LEGACY | WQ_MEM_RECLAIM, 1, (name)) create_workqueue is deprecated and it's observed that most of the subsystems have changed to using alloc_workqueue. So it's a small minority of few remnant instances in the kernel and some drivers still using create_workqueue. With the create_workqueue defined as is , it hardcodes the workqueue flags to be per cpu and unbound in nature and not giving the flexibility of using any other wait queue flags/attributes. ( WQ_CPU_INTENSIVE, WQ_HIGHPRI, WQ_RESCUER, WQ_FREEZEABLE, WQ_UNBOUND) . Hence most of the subsystems and drivers use the alloc_workqueue( ) api. #define create_workqueue(name) \ alloc_workqueue("%s", __WQ_LEGACY | WQ_MEM_RECLAIM, 1, (name)) > I think this should be noted in the changelog, at the very least, even > if it is fine. We should be as explicit as possible about behavior > changes. > imo, it's sort of known and consistently changed for quite some time alread= y. https://lists.openwall.net/linux-kernel/2016/06/07/1086 https://lists.openwall.net/linux-kernel/2011/01/03/124 https://lwn.net/Articles/403891/ =3D> quoted: "The long-term plan, it seems, is to convert all create_workqueue() users over to an appropriate alloc_workqueue() call; eventually create_workqueue() will be removed" glad to take some suggestions , thoughts ? BR, ronald