From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754063AbdGYBwk (ORCPT ); Mon, 24 Jul 2017 21:52:40 -0400 Received: from mga06.intel.com ([134.134.136.31]:23325 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753370AbdGYBwA (ORCPT ); Mon, 24 Jul 2017 21:52:00 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.40,409,1496127600"; d="scan'208";a="128988034" From: "Huang, Ying" To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , Johannes Weiner , Minchan Kim , Rik van Riel , Shaohua Li , Hugh Dickins , Fengguang Wu , Tim Chen , Dave Hansen Subject: [PATCH -mm -v3 1/6] mm, swap: Add swap cache statistics sysfs interface Date: Tue, 25 Jul 2017 09:51:46 +0800 Message-Id: <20170725015151.19502-2-ying.huang@intel.com> X-Mailer: git-send-email 2.13.2 In-Reply-To: <20170725015151.19502-1-ying.huang@intel.com> References: <20170725015151.19502-1-ying.huang@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Huang Ying The swap cache stats could be gotten only via sysrq, which isn't convenient in some situation. So the sysfs interface of swap cache stats is added for that. The added sysfs directories/files are as follow, /sys/kernel/mm/swap /sys/kernel/mm/swap/cache_find_total /sys/kernel/mm/swap/cache_find_success /sys/kernel/mm/swap/cache_add /sys/kernel/mm/swap/cache_del /sys/kernel/mm/swap/cache_pages Signed-off-by: "Huang, Ying" Cc: Johannes Weiner Cc: Minchan Kim Cc: Rik van Riel Cc: Shaohua Li Cc: Hugh Dickins Cc: Fengguang Wu Cc: Tim Chen Cc: Dave Hansen --- mm/swap_state.c | 78 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 78 insertions(+) diff --git a/mm/swap_state.c b/mm/swap_state.c index b68c93014f50..a13bbf504e93 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -561,3 +561,81 @@ void exit_swap_address_space(unsigned int type) synchronize_rcu(); kvfree(spaces); } + +#ifdef CONFIG_SYSFS +static ssize_t swap_cache_pages_show( + struct kobject *kobj, struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%lu\n", total_swapcache_pages()); +} +static struct kobj_attribute swap_cache_pages_attr = + __ATTR(cache_pages, 0444, swap_cache_pages_show, NULL); + +static ssize_t swap_cache_add_show( + struct kobject *kobj, struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%lu\n", swap_cache_info.add_total); +} +static struct kobj_attribute swap_cache_add_attr = + __ATTR(cache_add, 0444, swap_cache_add_show, NULL); + +static ssize_t swap_cache_del_show( + struct kobject *kobj, struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%lu\n", swap_cache_info.del_total); +} +static struct kobj_attribute swap_cache_del_attr = + __ATTR(cache_del, 0444, swap_cache_del_show, NULL); + +static ssize_t swap_cache_find_success_show( + struct kobject *kobj, struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%lu\n", swap_cache_info.find_success); +} +static struct kobj_attribute swap_cache_find_success_attr = + __ATTR(cache_find_success, 0444, swap_cache_find_success_show, NULL); + +static ssize_t swap_cache_find_total_show( + struct kobject *kobj, struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%lu\n", swap_cache_info.find_total); +} +static struct kobj_attribute swap_cache_find_total_attr = + __ATTR(cache_find_total, 0444, swap_cache_find_total_show, NULL); + +static struct attribute *swap_attrs[] = { + &swap_cache_pages_attr.attr, + &swap_cache_add_attr.attr, + &swap_cache_del_attr.attr, + &swap_cache_find_success_attr.attr, + &swap_cache_find_total_attr.attr, + NULL, +}; + +static struct attribute_group swap_attr_group = { + .attrs = swap_attrs, +}; + +static int __init swap_init_sysfs(void) +{ + int err; + struct kobject *swap_kobj; + + swap_kobj = kobject_create_and_add("swap", mm_kobj); + if (!swap_kobj) { + pr_err("failed to create swap kobject\n"); + return -ENOMEM; + } + err = sysfs_create_group(swap_kobj, &swap_attr_group); + if (err) { + pr_err("failed to register swap group\n"); + goto delete_obj; + } + return 0; + +delete_obj: + kobject_put(swap_kobj); + return err; +} +subsys_initcall(swap_init_sysfs); +#endif -- 2.13.2