kernel/watchdog.c:36:21: warning: 'watchdog_mutex' defined but not used

kernel/watchdog.c:36:21: warning: 'watchdog_mutex' defined but not used

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   a90ee4305c4a5df72c11b31dacfdc76e00fcf78a
commit: 25500ba7e77ce9d3d9b5a1929d41a2ee2e23f6fe locking/mutex: Remove the list_head from struct mutex
date:   7 months ago
config: powerpc64-randconfig-r2202-20261005 (https://download.01.org/0day-ci/archive/20261005/202610051721.Ul6QI2Or-lkp@intel.com/config)
compiler: powerpc64-linux-gcc (GCC) 12.5.0
smatch: v0.5.0-9187-g5189e3fb
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20261005/202610051721.Ul6QI2Or-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Fixes: 25500ba7e77c ("locking/mutex: Remove the list_head from struct mutex")
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202610051721.Ul6QI2Or-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from include/linux/kernfs.h:11,
                    from include/linux/sysfs.h:16,
                    from include/linux/kobject.h:20,
                    from include/linux/energy_model.h:7,
                    from include/linux/device.h:16,
                    from include/linux/node.h:18,
                    from include/linux/cpu.h:17,
                    from kernel/watchdog.c:15:
>> kernel/watchdog.c:36:21: warning: 'watchdog_mutex' defined but not used [-Wunused-variable]
      36 | static DEFINE_MUTEX(watchdog_mutex);
         |                     ^~~~~~~~~~~~~~
   include/linux/mutex.h:87:22: note: in definition of macro 'DEFINE_MUTEX'
      87 |         struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)
         |                      ^~~~~~~~~


vim +/watchdog_mutex +36 kernel/watchdog.c

58687acba592667 Don Zickus      2010-05-07  35  
946d197794b2320 Thomas Gleixner 2017-09-12 @36  static DEFINE_MUTEX(watchdog_mutex);
ab992dc38f9ae40 Peter Zijlstra  2015-05-18  37  

:::::: The code at line 36 was first introduced by commit
:::::: 946d197794b23202b8b46c43016747c72fe23393 watchdog/core: Rename watchdog_proc_mutex

:::::: TO: Thomas Gleixner <tglx@linutronix.de>
:::::: CC: Ingo Molnar <mingo@kernel.org>

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