Re: [linux-next:master 8472/9209] drivers/iommu/intel/perf.c:16: warning: expecting prototype for perf.c(). Prototype was for DEFINE_SPINLOCK() instead

[Lu Baolu <baolu.lu@linux.intel.com>]

On 6/12/21 7:47 PM, kernel test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> head:   25fe90f43fa312213b653dc1f12fd2d80f855883
> commit: 456bb0b97f00fe8defba155c0a4c48d951635395 [8472/9209] iommu/vt-d: Expose latency monitor data through debugfs
> config: x86_64-randconfig-a006-20210612 (attached as .config)
> compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project d2012d965d60c3258b3a69d024491698f8aec386)
> 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
>          # install x86_64 cross compiling tool for clang build
>          # apt-get install binutils-x86-64-linux-gnu
>          # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=456bb0b97f00fe8defba155c0a4c48d951635395
>          git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
>          git fetch --no-tags linux-next master
>          git checkout 456bb0b97f00fe8defba155c0a4c48d951635395
>          # save the attached .config to linux build tree
>          COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
> 
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
> 
> All warnings (new ones prefixed by >>):
> 
>     drivers/iommu/intel/perf.c:16: warning: Function parameter or member 'latency_lock' not described in 'DEFINE_SPINLOCK'
>>> drivers/iommu/intel/perf.c:16: warning: expecting prototype for perf.c(). Prototype was for DEFINE_SPINLOCK() instead

This seems to be a kernel doc warning and should be fixed in the header
file for DEFINE_SPINLOCK. Did I miss anything?

DEFINE_SPINLOCK is used everywhere, perhaps we need to add some comments
around it?

Best regards,
baolu

> 
> 
> vim +16 drivers/iommu/intel/perf.c
> 
> 55ee5e67a59a1b Lu Baolu 2021-06-10  15
> 55ee5e67a59a1b Lu Baolu 2021-06-10 @16  static DEFINE_SPINLOCK(latency_lock);
> 55ee5e67a59a1b Lu Baolu 2021-06-10  17
> 
> :::::: The code at line 16 was first introduced by commit
> :::::: 55ee5e67a59a1b6f388d7a1c7b24022145f47a3e iommu/vt-d: Add common code for dmar latency performance monitors
> 
> :::::: TO: Lu Baolu <baolu.lu@linux.intel.com>
> :::::: CC: Joerg Roedel <jroedel@suse.de>
> 
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
>