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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id DD3FEC6FD1D for ; Thu, 23 Mar 2023 07:59:34 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5B7356B0072; Thu, 23 Mar 2023 03:59:34 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 567DF6B0074; Thu, 23 Mar 2023 03:59:34 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 42F046B0075; Thu, 23 Mar 2023 03:59:34 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 3386B6B0072 for ; Thu, 23 Mar 2023 03:59:34 -0400 (EDT) Received: from smtpin19.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id EA06F1405F8 for ; Thu, 23 Mar 2023 07:59:33 +0000 (UTC) X-FDA: 80599413426.19.879D2C3 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by imf10.hostedemail.com (Postfix) with ESMTP id EBBB0C000F for ; Thu, 23 Mar 2023 07:59:31 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=none; dmarc=none; spf=none (imf10.hostedemail.com: domain of hch@lst.de has no SPF policy when checking 213.95.11.211) smtp.mailfrom=hch@lst.de ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1679558372; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=FgDQK3eUlH5Rqds1aM1Qgt3Y1oUND9OP/S1iLslhdxo=; b=W1ebQ6LrQax6JxKKAP5nJDQ/3BgZcfOXBgxCK+v8mPi6dbPSvwq3hR44SYHgAvYkYiTyUK dcYwO+2Hoxc9Ip0+9yXQQnfc+na9P61zVsV8vi40HnZ4vCVj9XuGmQ+jdQxjST0wVdPLeN 7A5GGzCJun0eXveaCVxv5nIuuVihgVo= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=none; dmarc=none; spf=none (imf10.hostedemail.com: domain of hch@lst.de has no SPF policy when checking 213.95.11.211) smtp.mailfrom=hch@lst.de ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1679558372; a=rsa-sha256; cv=none; b=QM1/W20Tb9+2g5oKWbRu0HWM1O7tmelBBzSgFLPBKUfdLFeeLAw7UYG/a04GZ8HpbZ6F70 E15flk89F6QiScg8BRLhTFEKojZjP4WlCWcf6ZuuZGwYNPzgVqvGVOz0W6zK/W2jRN9104 9Umb4cptfO49NLkRaZ5PYzwbBkOziXQ= Received: by verein.lst.de (Postfix, from userid 2407) id 5D07068AA6; Thu, 23 Mar 2023 08:59:27 +0100 (CET) Date: Thu, 23 Mar 2023 08:59:27 +0100 From: Christoph Hellwig To: Vitaly Wool Cc: Liu Shixin , Seth Jennings , Dan Streetman , Andrew Morton , Nathan Chancellor , Christoph Hellwig , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH -next v6 2/2] mm/zswap: delay the initializaton of zswap Message-ID: <20230323075927.GB20444@lst.de> References: <20230322102006.780624-1-liushixin2@huawei.com> <20230322102006.780624-3-liushixin2@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-Rspamd-Queue-Id: EBBB0C000F X-Stat-Signature: zy9ob89848iy6hszr6imzq1t1szuz3m5 X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1679558371-567791 X-HE-Meta: U2FsdGVkX1/eQjqrwN/y01WyFJMK+EbdQO3Zf7yx7KpiKxF60PLmHMa/mLxr6VuTdVJqLaz1E3xQU8xFFYMnlFLHyz9cPLUIpqAR5YfrJmtu9XW/KNETPoymzuw5aR0Tp0ieIX6u+vqQeJsHiKZGylicmc/XSOp+9QhxwuY75p2nvKT89vOqcPkl/eeNDoY9lMvHZDVK84gtFAA+yynHNDACXbRhBWgxjupF8PJau8LdeTa9jrKcJOT1q5LejAD5luOA9tq5Vyl0pltceooArkeu86KJOy2DN0mzuuXygrsc9dh3U9PMf6hTL0FLrklA/ODO5yal2wQ0YDFRyRDtHz41b43jQiKs0UXXlnqUhmfHNIcN5kLifujjAULcdnC24KH6GHEZh0gUaUESIUW+8hediULgHwANTlGmlSbHAZiJxHWq1/3RBUzHlCScDZN/Z4kFPdEMd/+T0UJgMqU1hRk/axRbnFY80mT6FLJzMdFDZ7rLzQdsuWvFfy79LiDlZ7xGy1aNFoAkdoXO8OMbI/qbLirELWZuujRX5m8SyNPGMp4DlC2kSgtjBIO4iTjDEoaF6byAXL4/x3ZK8KCWyii0QADey9h6Ul3zEeQREJCthjUlSVo8oA2IEEgXggsMBr1RBA5I+M/dX0/Yz/H0RcjxuGYwac3A1kt6a12Fr1Z/JURnefhtb8/Z4tDWK2c09uhRCkKeM+dOwdd47cmfWdkYQ4+rEubOBg+M233Y7V+u2dLOyCA3OUHT807w06obQJDbBADgGaoHsDCgwJmxcXGFvrXLv0L+a1Xp7rh9Ih87iIjYl7PMFXW/eOxd7Sz9UubQxMaCQfCYMOWNNsgHfiyLUAmGeyyZodAMyQHX6d+HXWEu6xzRAu0VqPdtuPrMyeWKPeCs2j6yThcDfPIbubqKFOClaqZaoBVaefGV/andPNiKTScHjTH5FSx3msIgGqV0QIQthDSUQGQUkCg ZbXvGeEK b7w9tTMOp73iBZ1NraN8iLowl+ZwIO5fRJf2InRf5BmFxq38tjtmnx13UCwKVeuNc8aeatdcSrz8OU4g7tVAjN7tu5/LN7wvJw0NC X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Mar 22, 2023 at 06:17:12PM +0100, Vitaly Wool wrote: > On Wed, Mar 22, 2023 at 10:30 AM Liu Shixin wrote: > > > > Since some users may not use zswap, the zswap_pool is wasted. Save memory > > by delaying the initialization of zswap until enabled. > > To be honest, I'm not a huge fan of this. Would enabling zswap module > build instead solve your problem? making zswap build modular would be a mess. It is core MM infrastructure and now we'd need to start dealing with adding and removing it at runtime as well as module refcounting.