[PATCH 3/3] PM: runtime: add debugfs entry for pm_runtime_summary

[Joshua Crofts <crofts@kernel.org>]

Add a debugfs entry for showing the runtime statistics for devices with
PM runtime enabled.

Signed-off-by: Joshua Crofts <crofts@kernel.org>
---
 drivers/base/power/runtime.c | 86 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 86 insertions(+)

diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index 5087a52f1784f7b4493896bce147ebcb0424d17c..f5ea6ba6d20fc4a9a3088e1fcb20b70cd5ebe476 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -14,6 +14,8 @@
 #include <linux/pm_runtime.h>
 #include <linux/pm_wakeirq.h>
 #include <linux/rculist.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
 #include <trace/events/rpm.h>
 
 #include "../base.h"
@@ -2193,3 +2195,87 @@ bool pm_runtime_need_not_resume(struct device *dev)
 }
 
 #endif /* CONFIG_PM_SLEEP */
+
+#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_PM_SLEEP)
+static void rpm_summary_show_dev(struct device *dev, void *data)
+{
+	struct seq_file *s = data;
+	unsigned long flags;
+	u64 active_time, suspended_time;
+	u64 last_sleep, min_sleep, max_sleep;
+	u64 resumes, suspends;
+	const char *status_str;
+	bool enabled;
+
+	spin_lock_irqsave(&dev->power.lock, flags);
+
+	enabled = pm_runtime_enabled(dev);
+	if (!enabled && !dev->power.resume_count && !dev->power.suspend_count) {
+		spin_unlock_irqrestore(&dev->power.lock, flags);
+		return;
+	}
+
+	update_pm_runtime_accounting(dev);
+
+	switch (dev->power.runtime_status) {
+	case RPM_ACTIVE:
+		status_str = "active";
+		break;
+	case RPM_SUSPENDED:
+		status_str = "suspended";
+		break;
+	case RPM_SUSPENDING:
+		status_str = "suspending";
+		break;
+	case RPM_RESUMING:
+		status_str = "resuming";
+		break;
+	default:
+		status_str = "unknown";
+		break;
+	}
+
+	active_time = dev->power.active_time;
+	suspended_time = dev->power.suspended_time;
+	resumes = dev->power.resume_count;
+	suspends = dev->power.suspend_count;
+	last_sleep = dev->power.last_suspended_time;
+	min_sleep = dev->power.min_suspended_time;
+	max_sleep = dev->power.max_suspended_time;
+
+	spin_unlock_irqrestore(&dev->power.lock, flags);
+
+	do_div(active_time, NSEC_PER_MSEC);
+	do_div(suspended_time, NSEC_PER_MSEC);
+	do_div(last_sleep, NSEC_PER_MSEC);
+	do_div(min_sleep, NSEC_PER_MSEC);
+	do_div(max_sleep, NSEC_PER_MSEC);
+
+	seq_printf(s, "%-32s %-12s %8llu %8llu %12llu %12llu %10llu %10llu %10llu\n",
+		   dev_name(dev), enabled ? status_str : "disabled",
+		   resumes, suspends, active_time, suspended_time,
+		   last_sleep, min_sleep, max_sleep);
+}
+
+static int pm_runtime_summary_show(struct seq_file *s, void *unused)
+{
+	seq_printf(s, "%-32s %-12s %8s %8s %12s %12s %10s %10s %10s\n",
+		   "Device", "Status", "Resumes", "Suspends",
+		   "Active(ms)", "Suspend(ms)", "Last(ms)", "Min(ms)", "Max(ms)");
+	seq_puts(s, "--------------------------------------------------------------------------------------------------------------------------\n");
+
+	dpm_for_each_dev(s, rpm_summary_show_dev);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(pm_runtime_summary);
+
+static int __init pm_runtime_debugfs_init(void)
+{
+	debugfs_create_file("pm_runtime_summary", 0444, NULL, NULL,
+			    &pm_runtime_summary_fops);
+
+	return 0;
+}
+late_initcall(pm_runtime_debugfs_init);
+#endif /* defined(CONFIG_DEBUG_FS) && defined(CONFIG_PM_SLEEP) */

-- 
2.47.3