From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751944AbaIJLa2 (ORCPT ); Wed, 10 Sep 2014 07:30:28 -0400 Received: from mailout2.w1.samsung.com ([210.118.77.12]:56641 "EHLO mailout2.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751077AbaIJLa0 (ORCPT ); Wed, 10 Sep 2014 07:30:26 -0400 X-AuditID: cbfec7f4-b7f156d0000063c7-0b-5410364ac6ec From: Maciej Matraszek To: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, "Rafael J. Wysocki" , Len Brown , Pavel Machek , Greg Kroah-Hartman Cc: Krzysztof Kozlowski , Bartlomiej Zolnierkiewicz , Maciej Matraszek Subject: [PATCH] PM / Domains: add debugfs listing of struct generic_pm_domain-s Date: Wed, 10 Sep 2014 13:28:56 +0200 Message-id: <1410348536-15201-1-git-send-email-m.matraszek@samsung.com> X-Mailer: git-send-email 1.9.1 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrDJMWRmVeSWpSXmKPExsVy+t/xa7peZgIhBm/+aFpsnLGe1aJ58Xo2 i9cvDC1mTdnLZHF51xw2i8+9RxgtTr64zGhx99RRNoszpy+xOnB6LN7zkslj/9w17B5brraz ePRtWcXosWL1d3aPz5vkAtiiuGxSUnMyy1KL9O0SuDIOPtnHWLDeuOLTIfEGxm/qXYwcHBIC JhL/djp0MXICmWISF+6tZ+ti5OIQEljKKLFi9TRGCKeXSWLTxsvsIFVsAgYSm//1s4AkRASu MUrsWbSMGcRhFpjOKLGkczobSJWwQIDE1nXfwDpYBFQlTr7/wQxi8wq4S9z/t5EFYp+cxMlj k1knMHIvYGRYxSiaWppcUJyUnmuoV5yYW1yal66XnJ+7iRESQl92MC4+ZnWIUYCDUYmHt/Ai f4gQa2JZcWXuIUYJDmYlEd40I4EQId6UxMqq1KL8+KLSnNTiQ4xMHJxSDYxbhee+W/Dhn1Ws RuvTPbqmmc82uYu+2L1TYp7qdZV8/98prydNkXTbfT1g45PCC32xJf9aNdYZzrg5IaWd8atc 7Yp3v6OnrpTS5HkSeXXqXc2zN5l4jlt8j655Mv2bjP4zmT8bp97lj7qRmP1RNUk+TY/1lcwF z/yTE88KHfsevvtN0FpW89OdSizFGYmGWsxFxYkA+UBcef8BAAA= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add /sys/kernel/debug/pm_genpd/pm_genpd_summary file, which lists power domains in the system, their statuses and attached devices, resembling /sys/kernel/debug/clk/clk_summary. Currently it is impossible to inspect (from userland) whether a power domain is on or off. And, if it is on, which device blocks it from powering down. This change allows developers working on embedded devices power efficiency to list all necessary information about generic power domains in one place. The content of pm_genpd/pm_genpd_summary file is generated by iterating over all generic power domain in the system, and, for each, over registered devices. Example output: $ cat /sys/kernel/debug/pm_genpd/pm_genpd_summary domain status slaves /device runtime status ---------------------------------------------------------------------- isp-power-domain off /devices/soc/12180000.fimc-is suspended /devices/soc/12180000.fimc-is/120a0000.fimc-lite suspended lcd0-power-domain on /devices/soc/11c80000.dsi active /devices/soc/11c00000.fimd active /devices/soc/11e20000.sysmmu suspended g3d-power-domain off /devices/soc/13001000.gpu suspended mfc-power-domain off /devices/soc/13400000.mfc-codec suspended /devices/soc/13620000.sysmmu suspended cam-power-domain off /devices/soc/11830000.jpeg-codec suspended /devices/soc/11a60000.sysmmu suspended /devices/soc/12180000.fimc-is/120c0000.csis suspended To enable this feature, compile the kernel with debugfs and CONFIG_PM_ADVANCED_DEBUG enabled. Signed-off-by: Maciej Matraszek --- drivers/base/power/domain.c | 153 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 153 insertions(+) diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index eee55c1e5fde..d1aa731ba0db 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -2189,3 +2189,156 @@ void pm_genpd_init(struct generic_pm_domain *genpd, list_add(&genpd->gpd_list_node, &gpd_list); mutex_unlock(&gpd_list_lock); } + + +/*** debugfs support ***/ + +#ifdef CONFIG_PM_ADVANCED_DEBUG +#include +#include +#include +#include +static struct dentry *pm_genpd_debugfs_dir; + +/* + * TODO: This function is a slightly modified version of rtpm_status_show + * from sysfs.c, but dependencies between PM_GENERIC_DOMAINS and PM_RUNTIME + * are too loose to generalize it. + */ +#ifdef CONFIG_PM_RUNTIME +static void rtpm_status_str(struct seq_file *s, struct device *dev) +{ + static const char * const status_lookup[] = { + [RPM_ACTIVE] = "active", + [RPM_RESUMING] = "resuming", + [RPM_SUSPENDED] = "suspended", + [RPM_SUSPENDING] = "suspending" + }; + const char *p = ""; + + if (dev->power.runtime_error) + p = "error"; + else if (dev->power.disable_depth) + p = "unsupported"; + else if (dev->power.runtime_status < ARRAY_SIZE(status_lookup)) + p = status_lookup[dev->power.runtime_status]; + else + WARN_ON(1); + + seq_puts(s, p); +} +#else +static void rtpm_status_str(struct seq_file *s, struct device *dev) +{ + seq_puts(s, "active"); +} +#endif + +static int pm_genpd_summary_one(struct seq_file *s, + struct generic_pm_domain *gpd) +{ + static const char * const status_lookup[] = { + [GPD_STATE_ACTIVE] = "on", + [GPD_STATE_WAIT_MASTER] = "wait-master", + [GPD_STATE_BUSY] = "busy", + [GPD_STATE_REPEAT] = "off-in-progress", + [GPD_STATE_POWER_OFF] = "off" + }; + struct pm_domain_data *pm_data; + const char *kobj_path; + struct gpd_link *link; + int ret; + + ret = mutex_lock_interruptible(&gpd->lock); + if (ret) + return -ERESTARTSYS; + + if (WARN_ON(gpd->status >= ARRAY_SIZE(status_lookup))) + goto exit; + seq_printf(s, "%-30s %-15s ", gpd->name, status_lookup[gpd->status]); + + /* + * Modifications on the list require holding locks on both + * master and slave, so we are safe. + * Also gpd->name is immutable. + */ + list_for_each_entry(link, &gpd->master_links, master_node) { + seq_printf(s, "%s", link->slave->name); + if (!list_is_last(&link->master_node, &gpd->master_links)) + seq_puts(s, ", "); + } + + list_for_each_entry(pm_data, &gpd->dev_list, list_node) { + kobj_path = kobject_get_path(&pm_data->dev->kobj, GFP_KERNEL); + if (kobj_path == NULL) + continue; + + seq_printf(s, "\n %-50s ", kobj_path); + rtpm_status_str(s, pm_data->dev); + kfree(kobj_path); + } + + seq_puts(s, "\n"); +exit: + mutex_unlock(&gpd->lock); + + return 0; +} + +static int pm_genpd_summary_show(struct seq_file *s, void *data) +{ + struct generic_pm_domain *gpd; + int ret = 0; + + seq_puts(s, " domain status slaves\n"); + seq_puts(s, " /device runtime status\n"); + seq_puts(s, "----------------------------------------------------------------------\n"); + + ret = mutex_lock_interruptible(&gpd_list_lock); + if (ret) + return -ERESTARTSYS; + + list_for_each_entry(gpd, &gpd_list, gpd_list_node) { + ret = pm_genpd_summary_one(s, gpd); + if (ret) + break; + } + mutex_unlock(&gpd_list_lock); + + return ret; +} + +static int pm_genpd_summary_open(struct inode *inode, struct file *file) +{ + return single_open(file, pm_genpd_summary_show, inode->i_private); +} + +static const struct file_operations pm_genpd_summary_fops = { + .open = pm_genpd_summary_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static int __init pm_genpd_debug_init(void) +{ + struct dentry *d; + + pm_genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL); + + /* No debugfs */ + if (IS_ERR(pm_genpd_debugfs_dir)) + return PTR_ERR(pm_genpd_debugfs_dir); + + if (!pm_genpd_debugfs_dir) + return -ENOMEM; + + d = debugfs_create_file("pm_genpd_summary", S_IRUGO, + pm_genpd_debugfs_dir, NULL, &pm_genpd_summary_fops); + if (!d) + return -ENOMEM; + + return 0; +} +late_initcall(pm_genpd_debug_init); +#endif /* CONFIG_PM_ADVANCED_DEBUG */ -- 1.9.1