diff mbox series

thermal/core: cooling device duplicate creation check

Message ID 20221027031648.2452-1-huangqibo.tech@gmail.com
State New
Headers
Series thermal/core: cooling device duplicate creation check |

Commit Message

Qibo Huang Oct. 27, 2022, 3:16 a.m. UTC 
  Because creating a cooling device may have duplicate names.
When creating, first check thermal_cdev_list whether
there is a device with the same name. If it has the same name,
it returns a reference to the cooling device.

Signed-off-by: Qibo Huang <huangqibo.tech@gmail.com>
---
 drivers/thermal/thermal_core.c | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

Comments

kernel test robot Oct. 27, 2022, 11:01 a.m. UTC | #1 
Hi Qibo,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on rafael-pm/thermal]
[also build test WARNING on linus/master v6.1-rc2 next-20221027]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Qibo-Huang/thermal-core-cooling-device-duplicate-creation-check/20221027-111751
base:   https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git thermal
patch link:    https://lore.kernel.org/r/20221027031648.2452-1-huangqibo.tech%40gmail.com
patch subject: [PATCH] thermal/core: cooling device duplicate creation check
config: x86_64-randconfig-a016
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/a48c9aab70c31e06e9e02f82cb2283153012dfa0
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Qibo-Huang/thermal-core-cooling-device-duplicate-creation-check/20221027-111751
        git checkout a48c9aab70c31e06e9e02f82cb2283153012dfa0
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/thermal/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/thermal/thermal_core.c:847:32: warning: no previous prototype for function 'thermal_cdev_get_zone_by_name' [-Wmissing-prototypes]
   struct thermal_cooling_device *thermal_cdev_get_zone_by_name(const char *name)
                                  ^
   drivers/thermal/thermal_core.c:847:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   struct thermal_cooling_device *thermal_cdev_get_zone_by_name(const char *name)
   ^
   static 
   1 warning generated.


vim +/thermal_cdev_get_zone_by_name +847 drivers/thermal/thermal_core.c

   846	
 > 847	struct thermal_cooling_device *thermal_cdev_get_zone_by_name(const char *name)
   848	{
   849		struct thermal_cooling_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
   850		unsigned int found = 0;
   851	
   852		if (!name)
   853			goto exit;
   854	
   855		mutex_lock(&thermal_list_lock);
   856		list_for_each_entry(pos, &thermal_cdev_list, node)
   857			if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
   858				found++;
   859				ref = pos;
   860			}
   861		mutex_unlock(&thermal_list_lock);
   862	
   863		/* nothing has been found, thus an error code for it */
   864		if (found == 0)
   865			ref = ERR_PTR(-ENODEV);
   866		else if (found > 1)
   867		/* Success only when an unique zone is found */
   868			ref = ERR_PTR(-EEXIST);
   869	
   870	exit:
   871		return ref;
   872	}
   873	EXPORT_SYMBOL_GPL(thermal_cdev_get_zone_by_name);
   874
kernel test robot Oct. 27, 2022, 11:12 a.m. UTC | #2 
Hi Qibo,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on rafael-pm/thermal]
[also build test WARNING on linus/master v6.1-rc2 next-20221027]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Qibo-Huang/thermal-core-cooling-device-duplicate-creation-check/20221027-111751
base:   https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git thermal
patch link:    https://lore.kernel.org/r/20221027031648.2452-1-huangqibo.tech%40gmail.com
patch subject: [PATCH] thermal/core: cooling device duplicate creation check
config: i386-randconfig-a013
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/a48c9aab70c31e06e9e02f82cb2283153012dfa0
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Qibo-Huang/thermal-core-cooling-device-duplicate-creation-check/20221027-111751
        git checkout a48c9aab70c31e06e9e02f82cb2283153012dfa0
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/thermal/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/thermal/thermal_core.c:847:32: warning: no previous prototype for function 'thermal_cdev_get_zone_by_name' [-Wmissing-prototypes]
   struct thermal_cooling_device *thermal_cdev_get_zone_by_name(const char *name)
                                  ^
   drivers/thermal/thermal_core.c:847:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   struct thermal_cooling_device *thermal_cdev_get_zone_by_name(const char *name)
   ^
   static 
   1 warning generated.


vim +/thermal_cdev_get_zone_by_name +847 drivers/thermal/thermal_core.c

   846	
 > 847	struct thermal_cooling_device *thermal_cdev_get_zone_by_name(const char *name)
   848	{
   849		struct thermal_cooling_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
   850		unsigned int found = 0;
   851	
   852		if (!name)
   853			goto exit;
   854	
   855		mutex_lock(&thermal_list_lock);
   856		list_for_each_entry(pos, &thermal_cdev_list, node)
   857			if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
   858				found++;
   859				ref = pos;
   860			}
   861		mutex_unlock(&thermal_list_lock);
   862	
   863		/* nothing has been found, thus an error code for it */
   864		if (found == 0)
   865			ref = ERR_PTR(-ENODEV);
   866		else if (found > 1)
   867		/* Success only when an unique zone is found */
   868			ref = ERR_PTR(-EEXIST);
   869	
   870	exit:
   871		return ref;
   872	}
   873	EXPORT_SYMBOL_GPL(thermal_cdev_get_zone_by_name);
   874
Rafael J. Wysocki Oct. 28, 2022, 5:42 p.m. UTC | #3 
On Thu, Oct 27, 2022 at 5:17 AM Qibo Huang <huangqibo.tech@gmail.com> wrote:
>
> Because creating a cooling device may have duplicate names.

Why is this a problem?

> When creating, first check thermal_cdev_list whether
> there is a device with the same name. If it has the same name,
> it returns a reference to the cooling device.

Why is this a correct and the best possible solution?

> Signed-off-by: Qibo Huang <huangqibo.tech@gmail.com>
> ---
>  drivers/thermal/thermal_core.c | 34 ++++++++++++++++++++++++++++++++++
>  1 file changed, 34 insertions(+)
>
> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> index 7e669b60a065..f38f9464e9f4 100644
> --- a/drivers/thermal/thermal_core.c
> +++ b/drivers/thermal/thermal_core.c
> @@ -844,6 +844,34 @@ static void bind_cdev(struct thermal_cooling_device *cdev)
>         mutex_unlock(&thermal_list_lock);
>  }
>
> +struct thermal_cooling_device *thermal_cdev_get_zone_by_name(const char *name)
> +{
> +       struct thermal_cooling_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
> +       unsigned int found = 0;
> +
> +       if (!name)
> +               goto exit;
> +
> +       mutex_lock(&thermal_list_lock);
> +       list_for_each_entry(pos, &thermal_cdev_list, node)
> +               if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
> +                       found++;
> +                       ref = pos;
> +               }
> +       mutex_unlock(&thermal_list_lock);
> +
> +       /* nothing has been found, thus an error code for it */
> +       if (found == 0)
> +               ref = ERR_PTR(-ENODEV);
> +       else if (found > 1)
> +       /* Success only when an unique zone is found */
> +               ref = ERR_PTR(-EEXIST);
> +
> +exit:
> +       return ref;
> +}
> +EXPORT_SYMBOL_GPL(thermal_cdev_get_zone_by_name);
> +
>  /**
>   * __thermal_cooling_device_register() - register a new thermal cooling device
>   * @np:                a pointer to a device tree node.
> @@ -873,6 +901,12 @@ __thermal_cooling_device_register(struct device_node *np,
>             !ops->set_cur_state)
>                 return ERR_PTR(-EINVAL);
>
> +       if (type) {
> +               cdev = thermal_cdev_get_zone_by_name(type);
> +               if (!IS_ERR(cdev))
> +                       return cdev;
> +       }
> +
>         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
>         if (!cdev)
>                 return ERR_PTR(-ENOMEM);
> --
> 2.37.1
>
diff mbox series

Patch

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 7e669b60a065..f38f9464e9f4 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -844,6 +844,34 @@  static void bind_cdev(struct thermal_cooling_device *cdev)
 	mutex_unlock(&thermal_list_lock);
 }
 
+struct thermal_cooling_device *thermal_cdev_get_zone_by_name(const char *name)
+{
+	struct thermal_cooling_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
+	unsigned int found = 0;
+
+	if (!name)
+		goto exit;
+
+	mutex_lock(&thermal_list_lock);
+	list_for_each_entry(pos, &thermal_cdev_list, node)
+		if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
+			found++;
+			ref = pos;
+		}
+	mutex_unlock(&thermal_list_lock);
+
+	/* nothing has been found, thus an error code for it */
+	if (found == 0)
+		ref = ERR_PTR(-ENODEV);
+	else if (found > 1)
+	/* Success only when an unique zone is found */
+		ref = ERR_PTR(-EEXIST);
+
+exit:
+	return ref;
+}
+EXPORT_SYMBOL_GPL(thermal_cdev_get_zone_by_name);
+
 /**
  * __thermal_cooling_device_register() - register a new thermal cooling device
  * @np:		a pointer to a device tree node.
@@ -873,6 +901,12 @@  __thermal_cooling_device_register(struct device_node *np,
 	    !ops->set_cur_state)
 		return ERR_PTR(-EINVAL);
 
+	if (type) {
+		cdev = thermal_cdev_get_zone_by_name(type);
+		if (!IS_ERR(cdev))
+			return cdev;
+	}
+
 	cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 	if (!cdev)
 		return ERR_PTR(-ENOMEM);