thermal: core: Add and use cooling device guard

Add and use a special guard for cooling devices.

This allows quite a few error code paths to be simplified among
other things and brings in code size reduction for a good measure.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/5837621.DvuYhMxLoT@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>

diff --git a/drivers/thermal/gov_power_allocator.c b/drivers/thermal/gov_power_allocator.c
index bdae60001b2c9834e20eb253577e812e40a9a4f4..5cb03923fa8f2f02422301e69c244c44ce78dea6 100644 (file)
--- a/drivers/thermal/gov_power_allocator.c
+++ b/drivers/thermal/gov_power_allocator.c
@@ -549,18 +549,17 @@ static void allow_maximum_power(struct thermal_zone_device *tz)
                cdev = instance->cdev;
 
                instance->target = 0;
-               mutex_lock(&cdev->lock);
-               /*
-                * Call for updating the cooling devices local stats and avoid
-                * periods of dozen of seconds when those have not been
-                * maintained.
-                */
-               cdev->ops->get_requested_power(cdev, &req_power);
-
-               if (params->update_cdevs)
-                       __thermal_cdev_update(cdev);
-
-               mutex_unlock(&cdev->lock);
+               scoped_guard(cooling_dev, cdev) {
+                       /*
+                        * Call for updating the cooling devices local stats and
+                        * avoid periods of dozen of seconds when those have not
+                        * been maintained.
+                        */
+                       cdev->ops->get_requested_power(cdev, &req_power);
+
+                       if (params->update_cdevs)
+                               __thermal_cdev_update(cdev);
+               }
        }
 }
 

diff --git a/drivers/thermal/gov_step_wise.c b/drivers/thermal/gov_step_wise.c
index ea4bf88d37f33791297cf1f0f45148bd5f0a57dd..d1bb59f1dfbd39c84fbc6fd47fc3b68612913134 100644 (file)
--- a/drivers/thermal/gov_step_wise.c
+++ b/drivers/thermal/gov_step_wise.c
@@ -97,9 +97,9 @@ static void thermal_zone_trip_update(struct thermal_zone_device *tz,
 
                instance->initialized = true;
 
-               mutex_lock(&instance->cdev->lock);
-               instance->cdev->updated = false; /* cdev needs update */
-               mutex_unlock(&instance->cdev->lock);
+               scoped_guard(cooling_dev, instance->cdev) {
+                       instance->cdev->updated = false; /* cdev needs update */
+               }
        }
 }
 

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index ab0c7c6396c0297aa8a0770a3f6cd939ee485dcc..f98aa396787af59adde03c7aba8ab5ac00bdb93f 100644 (file)
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -758,12 +758,10 @@ static int thermal_instance_add(struct thermal_instance *new_instance,
 
        list_add_tail(&new_instance->trip_node, &td->thermal_instances);
 
-       mutex_lock(&cdev->lock);
+       guard(cooling_dev)(cdev);
 
        list_add_tail(&new_instance->cdev_node, &cdev->thermal_instances);
 
-       mutex_unlock(&cdev->lock);
-
        return 0;
 }
 
@@ -872,11 +870,9 @@ static void thermal_instance_delete(struct thermal_instance *instance)
 {
        list_del(&instance->trip_node);
 
-       mutex_lock(&instance->cdev->lock);
+       guard(cooling_dev)(instance->cdev);
 
        list_del(&instance->cdev_node);
-
-       mutex_unlock(&instance->cdev->lock);
 }
 
 /**
@@ -1239,10 +1235,10 @@ void thermal_cooling_device_update(struct thermal_cooling_device *cdev)
         * Update under the cdev lock to prevent the state from being set beyond
         * the new limit concurrently.
         */
-       mutex_lock(&cdev->lock);
+       guard(cooling_dev)(cdev);
 
        if (cdev->ops->get_max_state(cdev, &cdev->max_state))
-               goto unlock;
+               return;
 
        thermal_cooling_device_stats_reinit(cdev);
 
@@ -1269,12 +1265,9 @@ void thermal_cooling_device_update(struct thermal_cooling_device *cdev)
        }
 
        if (cdev->ops->get_cur_state(cdev, &state) || state > cdev->max_state)
-               goto unlock;
+               return;
 
        thermal_cooling_device_stats_update(cdev, state);
-
-unlock:
-       mutex_unlock(&cdev->lock);
 }
 EXPORT_SYMBOL_GPL(thermal_cooling_device_update);
 

diff --git a/drivers/thermal/thermal_debugfs.c b/drivers/thermal/thermal_debugfs.c
index d67021aeb13670dc6fe4de759ead974d4082d8c6..c800504c3cfe0ea3b4a51286f348dd5802e1898f 100644 (file)
--- a/drivers/thermal/thermal_debugfs.c
+++ b/drivers/thermal/thermal_debugfs.c
@@ -516,6 +516,19 @@ void thermal_debug_cdev_add(struct thermal_cooling_device *cdev, int state)
        cdev->debugfs = thermal_dbg;
 }
 
+static struct thermal_debugfs *thermal_debug_cdev_clear(struct thermal_cooling_device *cdev)
+{
+       struct thermal_debugfs *thermal_dbg;
+
+       guard(cooling_dev)(cdev);
+
+       thermal_dbg = cdev->debugfs;
+       if (thermal_dbg)
+               cdev->debugfs = NULL;
+
+       return thermal_dbg;
+}
+
 /**
  * thermal_debug_cdev_remove - Remove a cooling device debugfs entry
  *
@@ -527,17 +540,9 @@ void thermal_debug_cdev_remove(struct thermal_cooling_device *cdev)
 {
        struct thermal_debugfs *thermal_dbg;
 
-       mutex_lock(&cdev->lock);
-
-       thermal_dbg = cdev->debugfs;
-       if (!thermal_dbg) {
-               mutex_unlock(&cdev->lock);
+       thermal_dbg = thermal_debug_cdev_clear(cdev);
+       if (!thermal_dbg)
                return;
-       }
-
-       cdev->debugfs = NULL;
-
-       mutex_unlock(&cdev->lock);
 
        mutex_lock(&thermal_dbg->lock);
 

diff --git a/drivers/thermal/thermal_helpers.c b/drivers/thermal/thermal_helpers.c
index 030a4e4bc824ca72f06a18231b0ea149f0948490..b1152ad7acc9005fc5ce95e3b522e9fb686d0778 100644 (file)
--- a/drivers/thermal/thermal_helpers.c
+++ b/drivers/thermal/thermal_helpers.c
@@ -58,17 +58,10 @@ bool thermal_trip_is_bound_to_cdev(struct thermal_zone_device *tz,
                                   const struct thermal_trip *trip,
                                   struct thermal_cooling_device *cdev)
 {
-       bool ret;
-
        guard(thermal_zone)(tz);
+       guard(cooling_dev)(cdev);
 
-       mutex_lock(&cdev->lock);
-
-       ret = thermal_instance_present(tz, cdev, trip);
-
-       mutex_unlock(&cdev->lock);
-
-       return ret;
+       return thermal_instance_present(tz, cdev, trip);
 }
 EXPORT_SYMBOL_GPL(thermal_trip_is_bound_to_cdev);
 
@@ -197,12 +190,12 @@ void __thermal_cdev_update(struct thermal_cooling_device *cdev)
  */
 void thermal_cdev_update(struct thermal_cooling_device *cdev)
 {
-       mutex_lock(&cdev->lock);
+       guard(cooling_dev)(cdev);
+
        if (!cdev->updated) {
                __thermal_cdev_update(cdev);
                cdev->updated = true;
        }
-       mutex_unlock(&cdev->lock);
 }
 
 /**
@@ -211,11 +204,9 @@ void thermal_cdev_update(struct thermal_cooling_device *cdev)
  */
 void thermal_cdev_update_nocheck(struct thermal_cooling_device *cdev)
 {
-       mutex_lock(&cdev->lock);
+       guard(cooling_dev)(cdev);
 
        __thermal_cdev_update(cdev);
-
-       mutex_unlock(&cdev->lock);
 }
 
 /**

diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c
index 701607a953ff49633bfc38674eb074bea3e27bb1..24b9055a0b6c515b865e0d7e2db1d0de176ff767 100644 (file)
--- a/drivers/thermal/thermal_sysfs.c
+++ b/drivers/thermal/thermal_sysfs.c
@@ -544,14 +544,15 @@ cur_state_store(struct device *dev, struct device_attribute *attr,
        if (state > cdev->max_state)
                return -EINVAL;
 
-       mutex_lock(&cdev->lock);
+       guard(cooling_dev)(cdev);
 
        result = cdev->ops->set_cur_state(cdev, state);
-       if (!result)
-               thermal_cooling_device_stats_update(cdev, state);
+       if (result)
+               return result;
+
+       thermal_cooling_device_stats_update(cdev, state);
 
-       mutex_unlock(&cdev->lock);
-       return result ? result : count;
+       return count;
 }
 
 static struct device_attribute
@@ -625,21 +626,18 @@ static ssize_t total_trans_show(struct device *dev,
 {
        struct thermal_cooling_device *cdev = to_cooling_device(dev);
        struct cooling_dev_stats *stats;
-       int ret = 0;
+       int ret;
 
-       mutex_lock(&cdev->lock);
+       guard(cooling_dev)(cdev);
 
        stats = cdev->stats;
        if (!stats)
-               goto unlock;
+               return 0;
 
        spin_lock(&stats->lock);
        ret = sprintf(buf, "%u\n", stats->total_trans);
        spin_unlock(&stats->lock);
 
-unlock:
-       mutex_unlock(&cdev->lock);
-
        return ret;
 }
 
@@ -652,11 +650,11 @@ time_in_state_ms_show(struct device *dev, struct device_attribute *attr,
        ssize_t len = 0;
        int i;
 
-       mutex_lock(&cdev->lock);
+       guard(cooling_dev)(cdev);
 
        stats = cdev->stats;
        if (!stats)
-               goto unlock;
+               return 0;
 
        spin_lock(&stats->lock);
 
@@ -668,9 +666,6 @@ time_in_state_ms_show(struct device *dev, struct device_attribute *attr,
        }
        spin_unlock(&stats->lock);
 
-unlock:
-       mutex_unlock(&cdev->lock);
-
        return len;
 }
 
@@ -682,11 +677,11 @@ reset_store(struct device *dev, struct device_attribute *attr, const char *buf,
        struct cooling_dev_stats *stats;
        int i, states;
 
-       mutex_lock(&cdev->lock);
+       guard(cooling_dev)(cdev);
 
        stats = cdev->stats;
        if (!stats)
-               goto unlock;
+               return count;
 
        states = cdev->max_state + 1;
 
@@ -702,9 +697,6 @@ reset_store(struct device *dev, struct device_attribute *attr, const char *buf,
 
        spin_unlock(&stats->lock);
 
-unlock:
-       mutex_unlock(&cdev->lock);
-
        return count;
 }
 
@@ -716,13 +708,11 @@ static ssize_t trans_table_show(struct device *dev,
        ssize_t len = 0;
        int i, j;
 
-       mutex_lock(&cdev->lock);
+       guard(cooling_dev)(cdev);
 
        stats = cdev->stats;
-       if (!stats) {
-               len = -ENODATA;
-               goto unlock;
-       }
+       if (!stats)
+               return -ENODATA;
 
        len += snprintf(buf + len, PAGE_SIZE - len, " From  :    To\n");
        len += snprintf(buf + len, PAGE_SIZE - len, "       : ");
@@ -731,10 +721,8 @@ static ssize_t trans_table_show(struct device *dev,
                        break;
                len += snprintf(buf + len, PAGE_SIZE - len, "state%2u  ", i);
        }
-       if (len >= PAGE_SIZE) {
-               len = PAGE_SIZE;
-               goto unlock;
-       }
+       if (len >= PAGE_SIZE)
+               return PAGE_SIZE;
 
        len += snprintf(buf + len, PAGE_SIZE - len, "\n");
 
@@ -760,9 +748,6 @@ static ssize_t trans_table_show(struct device *dev,
                len = -EFBIG;
        }
 
-unlock:
-       mutex_unlock(&cdev->lock);
-
        return len;
 }
 

diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index bcaa92732e14a4e827c5b2fd6f334bcc0c56a584..754802478b96a6b25ac016d825a5aed491b97e1a 100644 (file)
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -140,6 +140,9 @@ struct thermal_cooling_device {
 #endif
 };
 
+DEFINE_GUARD(cooling_dev, struct thermal_cooling_device *, mutex_lock(&_T->lock),
+            mutex_unlock(&_T->lock))
+
 /* Structure to define Thermal Zone parameters */
 struct thermal_zone_params {
        const char *governor_name;