From patchwork Fri Aug 26 07:34:30 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liu Shixin X-Patchwork-Id: 12955600 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 BA31EECAAD2 for ; Fri, 26 Aug 2022 07:00:04 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7A593940008; Fri, 26 Aug 2022 03:00:03 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 72E006B007B; Fri, 26 Aug 2022 03:00:03 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5CFDC940008; Fri, 26 Aug 2022 03:00:03 -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 4CF5C6B0078 for ; Fri, 26 Aug 2022 03:00:03 -0400 (EDT) Received: from smtpin12.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 2E5F2C039B for ; Fri, 26 Aug 2022 07:00:03 +0000 (UTC) X-FDA: 79840844286.12.27BE4AC Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by imf10.hostedemail.com (Postfix) with ESMTP id 08645C000C for ; Fri, 26 Aug 2022 07:00:01 +0000 (UTC) Received: from dggpemm500020.china.huawei.com (unknown [172.30.72.56]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4MDVwB6HWMzYcqW; Fri, 26 Aug 2022 14:55:38 +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; Fri, 26 Aug 2022 14:59:58 +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; Fri, 26 Aug 2022 14:59:57 +0800 From: Liu Shixin To: Seth Jennings , Dan Streetman , Vitaly Wool , Andrew Morton CC: , , Liu Shixin , Kefeng Wang Subject: [PATCH -next v2 1/3] mm/zswap: replace zswap_init_{started/failed} with zswap_init_state Date: Fri, 26 Aug 2022 15:34:30 +0800 Message-ID: <20220826073432.4168976-2-liushixin2@huawei.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220826073432.4168976-1-liushixin2@huawei.com> References: <20220826073432.4168976-1-liushixin2@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.113.32] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm100009.china.huawei.com (7.185.36.113) X-CFilter-Loop: Reflected ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf10.hostedemail.com: domain of liushixin2@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=liushixin2@huawei.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1661497202; a=rsa-sha256; cv=none; b=cfeJFSxDF2RdTLoIac6O9oJ9YykOOcfS7qJ3RtN69sCmfCgPyvRS5twOiricR0Ub74XpA1 /pI3HQkUkXiw5l19Qt7rxbs7yzao8OYiw6N7rpQPm4xzWbmqIg8BeCEiuPnr/FKA1yiXqZ G83NVW/W2qH4HKFb0bwjpkJmyqmjbAA= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1661497202; 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=+HmHSV2NYV3DgK5b2IIHOduZfAPoEHHLMKXhxHU3EVA=; b=jnGufH6mAKE+v/vAXIdts+poqyBZpKa7l3z7AkZ0ZbgqnFQQMVoOUioIOAiGXAjGLTVn4P 80yNIYYDET47QoBvPZgx+xbkEjsOlF2eErtvfk4jDE+UcyzpVZ61/SxXWVUdR2LSsx9MNh K87+PxI1hBZ1RhfS2x0f5iFH6xcx6N4= X-Stat-Signature: dqdn91omsczbouonbeh98m67qisk6ae6 Authentication-Results: imf10.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf10.hostedemail.com: domain of liushixin2@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=liushixin2@huawei.com X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 08645C000C X-Rspam-User: X-HE-Tag: 1661497201-244890 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: zswap_init_started indicates that the initialization is started. And zswap_init_failed indicates that the initialization is failed. As we will support to init zswap after system startup, it's necessary to add a state to indicate the initialization is complete and succeed to avoid concurrency issues. Since we don't care about the difference between init started with init completion. We only need three states: uninitialized, initial failed, initial succeed. Signed-off-by: Liu Shixin --- mm/zswap.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/mm/zswap.c b/mm/zswap.c index 2d48fd59cc7a..84e38300f571 100644 --- a/mm/zswap.c +++ b/mm/zswap.c @@ -214,11 +214,12 @@ static DEFINE_SPINLOCK(zswap_pools_lock); /* pool counter to provide unique names to zpool */ static atomic_t zswap_pools_count = ATOMIC_INIT(0); -/* used by param callback function */ -static bool zswap_init_started; +#define ZSWAP_UNINIT 0 +#define ZSWAP_INIT_SUCCEED 1 +#define ZSWAP_INIT_FAILED 2 -/* fatal error during init */ -static bool zswap_init_failed; +/* init state */ +static int zswap_init_state; /* init completed, but couldn't create the initial pool */ static bool zswap_has_pool; @@ -772,7 +773,7 @@ static int __zswap_param_set(const char *val, const struct kernel_param *kp, char *s = strstrip((char *)val); int ret; - if (zswap_init_failed) { + if (zswap_init_state == ZSWAP_INIT_FAILED) { pr_err("can't set param, initialization failed\n"); return -ENODEV; } @@ -784,7 +785,7 @@ static int __zswap_param_set(const char *val, const struct kernel_param *kp, /* if this is load-time (pre-init) param setting, * don't create a pool; that's done during init. */ - if (!zswap_init_started) + if (zswap_init_state == ZSWAP_UNINIT) return param_set_charp(s, kp); if (!type) { @@ -875,11 +876,11 @@ static int zswap_zpool_param_set(const char *val, static int zswap_enabled_param_set(const char *val, const struct kernel_param *kp) { - if (zswap_init_failed) { + if (zswap_init_state == ZSWAP_INIT_FAILED) { pr_err("can't enable, initialization failed\n"); return -ENODEV; } - if (!zswap_has_pool && zswap_init_started) { + if (!zswap_has_pool && zswap_init_state == ZSWAP_INIT_SUCCEED) { pr_err("can't enable, no pool configured\n"); return -ENODEV; } @@ -1476,8 +1477,6 @@ static int __init init_zswap(void) struct zswap_pool *pool; int ret; - zswap_init_started = true; - if (zswap_entry_cache_create()) { pr_err("entry cache creation failed\n"); goto cache_fail; @@ -1517,6 +1516,7 @@ static int __init init_zswap(void) goto destroy_wq; if (zswap_debugfs_init()) pr_warn("debugfs initialization failed\n"); + zswap_init_state = ZSWAP_INIT_SUCCEED; return 0; destroy_wq: @@ -1530,7 +1530,7 @@ static int __init init_zswap(void) zswap_entry_cache_destroy(); cache_fail: /* if built-in, we aren't unloaded on failure; don't allow use */ - zswap_init_failed = true; + zswap_init_state = ZSWAP_INIT_FAILED; zswap_enabled = false; return -ENOMEM; } From patchwork Fri Aug 26 07:34:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liu Shixin X-Patchwork-Id: 12955602 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 24906ECAAD2 for ; Fri, 26 Aug 2022 07:00:26 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A3E3C6B007B; 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Fri, 26 Aug 2022 14:56:01 +0800 (CST) Received: from dggpemm100009.china.huawei.com (7.185.36.113) by dggpemm500022.china.huawei.com (7.185.36.162) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 26 Aug 2022 14:59:58 +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; Fri, 26 Aug 2022 14:59:58 +0800 From: Liu Shixin To: Seth Jennings , Dan Streetman , Vitaly Wool , Andrew Morton CC: , , Liu Shixin , Kefeng Wang Subject: [PATCH -next v2 2/3] mm/zswap: delay the initializaton of zswap until the first enablement Date: Fri, 26 Aug 2022 15:34:31 +0800 Message-ID: <20220826073432.4168976-3-liushixin2@huawei.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220826073432.4168976-1-liushixin2@huawei.com> References: <20220826073432.4168976-1-liushixin2@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.113.32] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm100009.china.huawei.com (7.185.36.113) X-CFilter-Loop: Reflected ARC-Authentication-Results: i=1; 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dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf13.hostedemail.com: domain of liushixin2@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=liushixin2@huawei.com X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 6D31120020 X-Rspam-User: X-HE-Tag: 1661497224-420579 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 "); From patchwork Fri Aug 26 07:34:32 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liu Shixin X-Patchwork-Id: 12955601 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 83C18ECAAD2 for ; Fri, 26 Aug 2022 07:00:16 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 13D8C6B0078; Fri, 26 Aug 2022 03:00:16 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0C69C94000A; Fri, 26 Aug 2022 03:00:16 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EA94F940009; Fri, 26 Aug 2022 03:00:15 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id DBE076B0078 for ; Fri, 26 Aug 2022 03:00:15 -0400 (EDT) Received: from smtpin20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id ABA521A071F for ; Fri, 26 Aug 2022 07:00:15 +0000 (UTC) X-FDA: 79840844790.20.9D6EE52 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by imf30.hostedemail.com (Postfix) with ESMTP id DC74480025 for ; Fri, 26 Aug 2022 07:00:14 +0000 (UTC) Received: from dggpemm500023.china.huawei.com (unknown [172.30.72.56]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4MDVxM2yzPz19VdM; Fri, 26 Aug 2022 14:56:39 +0800 (CST) Received: from dggpemm100009.china.huawei.com (7.185.36.113) by dggpemm500023.china.huawei.com (7.185.36.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 26 Aug 2022 14:59:59 +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; Fri, 26 Aug 2022 14:59:58 +0800 From: Liu Shixin To: Seth Jennings , Dan Streetman , Vitaly Wool , Andrew Morton CC: , , Liu Shixin , Kefeng Wang Subject: [PATCH -next v2 3/3] mm/zswap: skip confusing print info Date: Fri, 26 Aug 2022 15:34:32 +0800 Message-ID: <20220826073432.4168976-4-liushixin2@huawei.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220826073432.4168976-1-liushixin2@huawei.com> References: <20220826073432.4168976-1-liushixin2@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.113.32] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm100009.china.huawei.com (7.185.36.113) X-CFilter-Loop: Reflected ARC-Seal: i=1; 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dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf30.hostedemail.com: domain of liushixin2@huawei.com designates 45.249.212.255 as permitted sender) smtp.mailfrom=liushixin2@huawei.com X-Rspam-User: X-Rspamd-Queue-Id: DC74480025 X-Rspamd-Server: rspam08 X-Stat-Signature: apjy8iqf7xfntwj5rrff4m7uqoh5t8i3 X-HE-Tag: 1661497214-529082 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: It's confusing when we disable zswap while zswap is init failed or has no pool. If no change required, just return directly. Signed-off-by: Liu Shixin --- mm/zswap.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/mm/zswap.c b/mm/zswap.c index 4c476c463035..ef7463550e49 100644 --- a/mm/zswap.c +++ b/mm/zswap.c @@ -886,6 +886,15 @@ static int zswap_zpool_param_set(const char *val, static int zswap_enabled_param_set(const char *val, const struct kernel_param *kp) { + bool res; + + if (kstrtobool(val, &res)) + return -EINVAL; + + /* no change required */ + if (res == *(bool *)kp->arg) + return 0; + if (system_state == SYSTEM_RUNNING) { mutex_lock(&zswap_init_lock); if (zswap_setup()) {