From patchwork Thu Sep 15 03:50:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liu Shixin X-Patchwork-Id: 12976802 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 CBBCFECAAD8 for ; Thu, 15 Sep 2022 03:16:14 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 456E98D0001; Wed, 14 Sep 2022 23:16:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 406BD6B0073; Wed, 14 Sep 2022 23:16:14 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2CEB38D0001; Wed, 14 Sep 2022 23:16:14 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 1DACE6B0071 for ; Wed, 14 Sep 2022 23:16:14 -0400 (EDT) Received: from smtpin28.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id E1F1AA0B24 for ; Thu, 15 Sep 2022 03:16:13 +0000 (UTC) X-FDA: 79912856226.28.41152FD Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by imf17.hostedemail.com (Postfix) with ESMTP id 8773140098 for ; Thu, 15 Sep 2022 03:16:11 +0000 (UTC) Received: from dggpemm500020.china.huawei.com (unknown [172.30.72.53]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4MSj0M6kfrzNmK1; Thu, 15 Sep 2022 11:11:31 +0800 (CST) Received: from dggpemm100009.china.huawei.com (7.185.36.113) by dggpemm500020.china.huawei.com (7.185.36.49) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 15 Sep 2022 11:16:08 +0800 Received: from huawei.com (10.175.113.32) by dggpemm100009.china.huawei.com (7.185.36.113) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 15 Sep 2022 11:16:07 +0800 From: Liu Shixin To: Seth Jennings , Dan Streetman , Vitaly Wool , Andrew Morton , Nathan Chancellor , "Christoph Hellwig" CC: , , Liu Shixin , Kefeng Wang Subject: [PATCH v5 4/5] mm/zswap: delay the initializaton of zswap until the first enablement Date: Thu, 15 Sep 2022 11:50:02 +0800 Message-ID: <20220915035003.3347466-5-liushixin2@huawei.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220915035003.3347466-1-liushixin2@huawei.com> References: <20220915035003.3347466-1-liushixin2@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.113.32] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpemm100009.china.huawei.com (7.185.36.113) X-CFilter-Loop: Reflected ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1663211773; 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=ygudW5h3+fGZn8qgaKuqS8DlGNtvOI0q05JNF5mAobg=; b=uVVSBrRsm07nZmWfUACAhdLFHrr8Id+eUAI2IQkEtZXLrrd+DaWMR6srpxxOP6Z5sCdeTy rBk7+oxYj70N84Cpr7qDGgamB+mRcpU8ce3sVHlK/PhpJdNrMxq8CAVGM3y1nkTGjW8Gkm R9l4ysJA3X4a4XBdqEdN/3RrECPpFe4= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=none; spf=pass (imf17.hostedemail.com: domain of liushixin2@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=liushixin2@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1663211773; a=rsa-sha256; cv=none; b=cBlZQWbK9sTLsQPPUMsSZZJTNWySpVhIXPibQYcU98PIJ0Yi4N0MLqn77CBX5+Oo5Yijp0 ai/N6VBlPOmnhvfAZ375KwSQNZwNE80q+eFYNfnhGnZ0PDlrrzc5lCxISADva0tIXtsJvH D4ZwHBwGJNxWTMtOXiYCwmFLxhdhzi8= Authentication-Results: imf17.hostedemail.com; dkim=none; spf=pass (imf17.hostedemail.com: domain of liushixin2@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=liushixin2@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com X-Rspamd-Server: rspam08 X-Rspam-User: X-Stat-Signature: fipg51dbia64arztkc8ueb4jzh7hzg5i X-Rspamd-Queue-Id: 8773140098 X-HE-Tag: 1663211771-786693 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: In the initialization of zswap, about 18MB memory will be allocated for zswap_pool in my machine. Since not all users use zswap, the memory may be wasted. Save the memory for these users by delaying the initialization of zswap to first enablement. Signed-off-by: Liu Shixin --- mm/zswap.c | 50 ++++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 40 insertions(+), 10 deletions(-) diff --git a/mm/zswap.c b/mm/zswap.c index 84e38300f571..4c476c463035 100644 --- a/mm/zswap.c +++ b/mm/zswap.c @@ -81,6 +81,8 @@ static bool zswap_pool_reached_full; #define ZSWAP_PARAM_UNSET "" +static int zswap_setup(void); + /* Enable/disable zswap */ static bool zswap_enabled = IS_ENABLED(CONFIG_ZSWAP_DEFAULT_ON); static int zswap_enabled_param_set(const char *, @@ -220,6 +222,8 @@ static atomic_t zswap_pools_count = ATOMIC_INIT(0); /* init state */ static int zswap_init_state; +/* used to ensure the integrity of initialization */ +static DEFINE_MUTEX(zswap_init_lock); /* init completed, but couldn't create the initial pool */ static bool zswap_has_pool; @@ -273,13 +277,13 @@ static void zswap_update_total_size(void) **********************************/ static struct kmem_cache *zswap_entry_cache; -static int __init zswap_entry_cache_create(void) +static int zswap_entry_cache_create(void) { zswap_entry_cache = KMEM_CACHE(zswap_entry, 0); return zswap_entry_cache == NULL; } -static void __init zswap_entry_cache_destroy(void) +static void zswap_entry_cache_destroy(void) { kmem_cache_destroy(zswap_entry_cache); } @@ -664,7 +668,7 @@ static struct zswap_pool *zswap_pool_create(char *type, char *compressor) return NULL; } -static __init struct zswap_pool *__zswap_pool_create_fallback(void) +static struct zswap_pool *__zswap_pool_create_fallback(void) { bool has_comp, has_zpool; @@ -782,11 +786,17 @@ static int __zswap_param_set(const char *val, const struct kernel_param *kp, if (!strcmp(s, *(char **)kp->arg) && zswap_has_pool) return 0; - /* if this is load-time (pre-init) param setting, + /* + * if zswap has not been initialized, * don't create a pool; that's done during init. */ - if (zswap_init_state == ZSWAP_UNINIT) - return param_set_charp(s, kp); + mutex_lock(&zswap_init_lock); + if (zswap_init_state == ZSWAP_UNINIT) { + ret = param_set_charp(s, kp); + mutex_unlock(&zswap_init_lock); + return ret; + } + mutex_unlock(&zswap_init_lock); if (!type) { if (!zpool_has_pool(s)) { @@ -876,6 +886,14 @@ static int zswap_zpool_param_set(const char *val, static int zswap_enabled_param_set(const char *val, const struct kernel_param *kp) { + if (system_state == SYSTEM_RUNNING) { + mutex_lock(&zswap_init_lock); + if (zswap_setup()) { + mutex_unlock(&zswap_init_lock); + return -ENODEV; + } + mutex_unlock(&zswap_init_lock); + } if (zswap_init_state == ZSWAP_INIT_FAILED) { pr_err("can't enable, initialization failed\n"); return -ENODEV; @@ -1432,7 +1450,7 @@ static const struct frontswap_ops zswap_frontswap_ops = { static struct dentry *zswap_debugfs_root; -static int __init zswap_debugfs_init(void) +static int zswap_debugfs_init(void) { if (!debugfs_initialized()) return -ENODEV; @@ -1463,7 +1481,7 @@ static int __init zswap_debugfs_init(void) return 0; } #else -static int __init zswap_debugfs_init(void) +static int zswap_debugfs_init(void) { return 0; } @@ -1472,11 +1490,14 @@ static int __init zswap_debugfs_init(void) /********************************* * module init and exit **********************************/ -static int __init init_zswap(void) +static int zswap_setup(void) { struct zswap_pool *pool; int ret; + if (zswap_init_state != ZSWAP_UNINIT) + return 0; + if (zswap_entry_cache_create()) { pr_err("entry cache creation failed\n"); goto cache_fail; @@ -1534,8 +1555,17 @@ static int __init init_zswap(void) zswap_enabled = false; return -ENOMEM; } + +static int __init zswap_init(void) +{ + /* skip init if zswap is disabled when system startup */ + if (!zswap_enabled) + return 0; + return zswap_setup(); +} + /* must be late so crypto has time to come up */ -late_initcall(init_zswap); +late_initcall(zswap_init); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Seth Jennings ");