Re: [PATCH V1 2/2] mm/damon/core: remove duplicate check about THP

[Andrew Morton <akpm@linux-foundation.org>]

On Fri, 16 Sep 2022 05:54:56 +0800 kernel test robot <lkp@intel.com> wrote:

> Hi Xin,
> 
> Thank you for the patch! Yet something to improve:
> 
> [auto build test ERROR on akpm-mm/mm-everything]
> 
> url:    https://github.com/intel-lab-lkp/linux/commits/Xin-Hao/mm-damon-sysfs-avoid-call-damon_target_has_pid-repeatedly/20220915-230635
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
> config: hexagon-randconfig-r002-20220915 (https://download.01.org/0day-ci/archive/20220916/202209160528.6z2rUbjZ-lkp@intel.com/config)
> compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 791a7ae1ba3efd6bca96338e10ffde557ba83920)
> 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/7902790b04d0eb74686b55218e8ead191ba5c003
>         git remote add linux-review https://github.com/intel-lab-lkp/linux
>         git fetch --no-tags linux-review Xin-Hao/mm-damon-sysfs-avoid-call-damon_target_has_pid-repeatedly/20220915-230635
>         git checkout 7902790b04d0eb74686b55218e8ead191ba5c003
>         # 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=hexagon SHELL=/bin/bash mm/damon/
> 
> If you fix the issue, kindly add following tag where applicable
> Reported-by: kernel test robot <lkp@intel.com>
> 
> All errors (new ones prefixed by >>):
> 
> >> mm/damon/vaddr.c:451:7: error: call to undeclared function 'pmd_young'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
>                    if (pmd_young(*pmd) || !page_is_idle(page) ||
>                        ^
>    mm/damon/vaddr.c:451:7: note: did you mean 'pte_young'?
>    arch/hexagon/include/asm/pgtable.h:273:19: note: 'pte_young' declared here
>    static inline int pte_young(pte_t pte)
>                      ^

Thanks.  I guess the arch needn't implement pmd_young() if it doesn't
implement THP.

I dropped the patch.