thermal/debugfs: Pass cooling device state to thermal_debug_cdev_add()

If cdev_dt_seq_show() runs before the first state transition of a cooling
device, it will not print any state residency information for it, even
though it might be reasonably expected to print residency information for
the initial state of the cooling device.

For this reason, rearrange the code to get the initial state of a cooling
device at the registration time and pass it to thermal_debug_cdev_add(),
so that the latter can create a duration record for that state which will
allow cdev_dt_seq_show() to print its residency information.

Fixes: 755113d76786 ("thermal/debugfs: Add thermal cooling device debugfs information")
Reported-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Tested-by: Lukasz Luba <lukasz.luba@arm.com>

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 64036372e240c412810d674b38c0eb928c406629..f43237ef2cd0616709e4c2175d1161e6bcea780b 100644 (file)
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -935,6 +935,7 @@ __thermal_cooling_device_register(struct device_node *np,
 {
        struct thermal_cooling_device *cdev;
        struct thermal_zone_device *pos = NULL;
+       unsigned long current_state;
        int id, ret;
 
        if (!ops || !ops->get_max_state || !ops->get_cur_state ||
@@ -972,6 +973,10 @@ __thermal_cooling_device_register(struct device_node *np,
        if (ret)
                goto out_cdev_type;
 
+       ret = cdev->ops->get_cur_state(cdev, &current_state);
+       if (ret)
+               goto out_cdev_type;
+
        thermal_cooling_device_setup_sysfs(cdev);
 
        ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
@@ -985,6 +990,8 @@ __thermal_cooling_device_register(struct device_node *np,
                return ERR_PTR(ret);
        }
 
+       thermal_debug_cdev_add(cdev, current_state);
+
        /* Add 'this' new cdev to the global cdev list */
        mutex_lock(&thermal_list_lock);
 
@@ -1000,8 +1007,6 @@ __thermal_cooling_device_register(struct device_node *np,
 
        mutex_unlock(&thermal_list_lock);
 
-       thermal_debug_cdev_add(cdev);
-
        return cdev;
 
 out_cooling_dev:

diff --git a/drivers/thermal/thermal_debugfs.c b/drivers/thermal/thermal_debugfs.c
index c93d2b5405ded0727f8de0ea418e9274f6526fce..59b1d999383c3e4a8d3a3b78f849fc0793ec2009 100644 (file)
--- a/drivers/thermal/thermal_debugfs.c
+++ b/drivers/thermal/thermal_debugfs.c
@@ -468,8 +468,9 @@ void thermal_debug_cdev_state_update(const struct thermal_cooling_device *cdev,
  * Allocates a cooling device object for debug, initializes the
  * statistics and create the entries in sysfs.
  * @cdev: a pointer to a cooling device
+ * @state: current state of the cooling device
  */
-void thermal_debug_cdev_add(struct thermal_cooling_device *cdev)
+void thermal_debug_cdev_add(struct thermal_cooling_device *cdev, int state)
 {
        struct thermal_debugfs *thermal_dbg;
        struct cdev_debugfs *cdev_dbg;
@@ -486,9 +487,16 @@ void thermal_debug_cdev_add(struct thermal_cooling_device *cdev)
                INIT_LIST_HEAD(&cdev_dbg->durations[i]);
        }
 
-       cdev_dbg->current_state = 0;
+       cdev_dbg->current_state = state;
        cdev_dbg->timestamp = ktime_get();
 
+       /*
+        * Create a record for the initial cooling device state, so its
+        * duration will be printed by cdev_dt_seq_show() as expected if it
+        * runs before the first state transition.
+        */
+       thermal_debugfs_cdev_record_get(thermal_dbg, cdev_dbg->durations, state);
+
        debugfs_create_file("trans_table", 0400, thermal_dbg->d_top,
                            thermal_dbg, &tt_fops);
 

diff --git a/drivers/thermal/thermal_debugfs.h b/drivers/thermal/thermal_debugfs.h
index 027c145501dde4963a4db866509f63397c9a18fe..74ee65ee82ff8b4014b5fb8bedca4586d9a26cd8 100644 (file)
--- a/drivers/thermal/thermal_debugfs.h
+++ b/drivers/thermal/thermal_debugfs.h
@@ -2,7 +2,7 @@
 
 #ifdef CONFIG_THERMAL_DEBUGFS
 void thermal_debug_init(void);
-void thermal_debug_cdev_add(struct thermal_cooling_device *cdev);
+void thermal_debug_cdev_add(struct thermal_cooling_device *cdev, int state);
 void thermal_debug_cdev_remove(struct thermal_cooling_device *cdev);
 void thermal_debug_cdev_state_update(const struct thermal_cooling_device *cdev, int state);
 void thermal_debug_tz_add(struct thermal_zone_device *tz);
@@ -14,7 +14,7 @@ void thermal_debug_tz_trip_down(struct thermal_zone_device *tz,
 void thermal_debug_update_trip_stats(struct thermal_zone_device *tz);
 #else
 static inline void thermal_debug_init(void) {}
-static inline void thermal_debug_cdev_add(struct thermal_cooling_device *cdev) {}
+static inline void thermal_debug_cdev_add(struct thermal_cooling_device *cdev, int state) {}
 static inline void thermal_debug_cdev_remove(struct thermal_cooling_device *cdev) {}
 static inline void thermal_debug_cdev_state_update(const struct thermal_cooling_device *cdev,
                                                   int state) {}