Re: [PATCH] tracing/timerlat: Hotplug support for the user-space interface

[Daniel Bristot de Oliveira <bristot@kernel.org>]

On 9/16/23 02:21, kernel test robot wrote:
> Hi Daniel,
> 
> kernel test robot noticed the following build warnings:
> 
> [auto build test WARNING on linus/master]
> [also build test WARNING on v6.6-rc1 next-20230915]
> [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/Daniel-Bristot-de-Oliveira/tracing-timerlat-Hotplug-support-for-the-user-space-interface/20230915-230157
> base:   linus/master
> patch link:    https://lore.kernel.org/r/b619d9fd08a3bb47018cf40afa95783844a3c1fd.1694789910.git.bristot%40kernel.org
> patch subject: [PATCH] tracing/timerlat: Hotplug support for the user-space interface
> config: um-randconfig-002-20230916 (https://download.01.org/0day-ci/archive/20230916/202309160854.SAw0rIUm-lkp@intel.com/config)
> 

^^ The config has no timerlat and no hotplug...

compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230916/202309160854.SAw0rIUm-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
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202309160854.SAw0rIUm-lkp@intel.com/
> 
> All warnings (new ones prefixed by >>):
> 
>>> kernel/trace/trace_osnoise.c:2125:13: warning: 'timerlat_rm_per_cpu_interface' defined but not used [-Wunused-function]
>     2125 | static void timerlat_rm_per_cpu_interface(long cpu) {};
>          |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>> kernel/trace/trace_osnoise.c:2124:12: warning: 'timerlat_add_per_cpu_interface' defined but not used [-Wunused-function]
>     2124 | static int timerlat_add_per_cpu_interface(long cpu) { return 0; };
>          |            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

These functions are called when hotplug but no timerlat.... when no hotplug: defined but not used.

> 
> vim +/timerlat_rm_per_cpu_interface +2125 kernel/trace/trace_osnoise.c
> 
>   2112	
>   2113	static void timerlat_rm_per_cpu_interface(long cpu)
>   2114	{
>   2115		struct dentry *cpu_dir = per_cpu_ptr(&osnoise_per_cpu_dir, cpu)->root;
>   2116	
>   2117		if (cpu_dir) {
>   2118			tracefs_remove(cpu_dir);
>   2119			per_cpu_ptr(&osnoise_per_cpu_dir, cpu)->root = NULL;
>   2120			per_cpu_ptr(&osnoise_per_cpu_dir, cpu)->timerlat_fd = NULL;
>   2121		}
>   2122	}
>   2123	#else
>> 2124	static int timerlat_add_per_cpu_interface(long cpu) { return 0; };
>> 2125	static void timerlat_rm_per_cpu_interface(long cpu) {};
>   2126	#endif
>   2127	
> 

Fixing it.

-- Daniel