linux-kernel - [PATCH] PM: domains: create debugfs nodes when adding power domains

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20201203233546.3482813-1-tstrudel@google.com>
Date:   Thu,  3 Dec 2020 15:35:46 -0800
From:   Thierry Strudel <tstrudel@...gle.com>
To:     "Rafael J. Wysocki" <rjw@...ysocki.net>,
        Kevin Hilman <khilman@...nel.org>,
        Ulf Hansson <ulf.hansson@...aro.org>
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org,
        Thierry Strudel <tstrudel@...gle.com>
Subject: [PATCH] PM: domains: create debugfs nodes when adding power domains

debugfs nodes were created in genpd_debug_init alled in late_initcall
preventing power domains registered though loadable modules to have
a debugfs entry.

Create/remove debugfs nodes when the power domain is added/removed
to/from the internal gpd_list.

Signed-off-by: Thierry Strudel <tstrudel@...gle.com>
---
 drivers/base/power/domain.c | 61 ++++++++++++++++++++++++-------------
 1 file changed, 39 insertions(+), 22 deletions(-)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 743268996336..3f168ec93762 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -1880,6 +1880,8 @@ static void genpd_lock_init(struct generic_pm_domain *genpd)
 	}
 }
 
+static void genpd_debug_add(struct generic_pm_domain *genpd);
+
 /**
  * pm_genpd_init - Initialize a generic I/O PM domain object.
  * @genpd: PM domain object to initialize.
@@ -1954,12 +1956,15 @@ int pm_genpd_init(struct generic_pm_domain *genpd,
 
 	mutex_lock(&gpd_list_lock);
 	list_add(&genpd->gpd_list_node, &gpd_list);
+	genpd_debug_add(genpd);
 	mutex_unlock(&gpd_list_lock);
 
 	return 0;
 }
 EXPORT_SYMBOL_GPL(pm_genpd_init);
 
+static void genpd_debug_remove(struct generic_pm_domain *genpd);
+
 static int genpd_remove(struct generic_pm_domain *genpd)
 {
 	struct gpd_link *l, *link;
@@ -1987,6 +1992,7 @@ static int genpd_remove(struct generic_pm_domain *genpd)
 		kfree(link);
 	}
 
+	genpd_debug_remove(genpd);
 	list_del(&genpd->gpd_list_node);
 	genpd_unlock(genpd);
 	cancel_work_sync(&genpd->power_off_work);
@@ -3177,36 +3183,44 @@ DEFINE_SHOW_ATTRIBUTE(total_idle_time);
 DEFINE_SHOW_ATTRIBUTE(devices);
 DEFINE_SHOW_ATTRIBUTE(perf_state);
 
-static int __init genpd_debug_init(void)
+static void genpd_debug_add(struct generic_pm_domain *genpd)
 {
 	struct dentry *d;
-	struct generic_pm_domain *genpd;
 
+	d = debugfs_create_dir(genpd->name, genpd_debugfs_dir);
+
+	debugfs_create_file("current_state", 0444,
+			    d, genpd, &status_fops);
+	debugfs_create_file("sub_domains", 0444,
+			    d, genpd, &sub_domains_fops);
+	debugfs_create_file("idle_states", 0444,
+			    d, genpd, &idle_states_fops);
+	debugfs_create_file("active_time", 0444,
+			    d, genpd, &active_time_fops);
+	debugfs_create_file("total_idle_time", 0444,
+			    d, genpd, &total_idle_time_fops);
+	debugfs_create_file("devices", 0444,
+			    d, genpd, &devices_fops);
+	if (genpd->set_performance_state)
+		debugfs_create_file("perf_state", 0444,
+				    d, genpd, &perf_state_fops);
+}
+
+static void genpd_debug_remove(struct generic_pm_domain *genpd)
+{
+	struct dentry *d;
+
+	d = debugfs_lookup(genpd->name, genpd_debugfs_dir);
+	debugfs_remove(d);
+}
+
+static int __init genpd_debug_init(void)
+{
 	genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
 
 	debugfs_create_file("pm_genpd_summary", S_IRUGO, genpd_debugfs_dir,
 			    NULL, &summary_fops);
 
-	list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
-		d = debugfs_create_dir(genpd->name, genpd_debugfs_dir);
-
-		debugfs_create_file("current_state", 0444,
-				d, genpd, &status_fops);
-		debugfs_create_file("sub_domains", 0444,
-				d, genpd, &sub_domains_fops);
-		debugfs_create_file("idle_states", 0444,
-				d, genpd, &idle_states_fops);
-		debugfs_create_file("active_time", 0444,
-				d, genpd, &active_time_fops);
-		debugfs_create_file("total_idle_time", 0444,
-				d, genpd, &total_idle_time_fops);
-		debugfs_create_file("devices", 0444,
-				d, genpd, &devices_fops);
-		if (genpd->set_performance_state)
-			debugfs_create_file("perf_state", 0444,
-					    d, genpd, &perf_state_fops);
-	}
-
 	return 0;
 }
 late_initcall(genpd_debug_init);
@@ -3216,4 +3230,7 @@ static void __exit genpd_debug_exit(void)
 	debugfs_remove_recursive(genpd_debugfs_dir);
 }
 __exitcall(genpd_debug_exit);
+#else
+static void genpd_debug_add(struct generic_pm_domain *genpd) {}
+static void genpd_debug_remove(struct generic_pm_domain *genpd) {}
 #endif /* CONFIG_DEBUG_FS */
-- 
2.29.2.576.ga3fc446d84-goog