Re: [PATCH 1/7] MIPS: sync-r4k: Rework to be many cores firendly

[kernel test robot <lkp@xxxxxxxxx>]

Hi Jiaxun,

I love your patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on v5.9-rc1 next-20200821]
[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]

url:    https://github.com/0day-ci/linux/commits/Jiaxun-Yang/R4000-clock-enhancements-for-Loongson/20200817-115351
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 9123e3a74ec7b934a4a099e98af6a61c2f80bbf5
config: mips-randconfig-r014-20200820 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project b587ca93be114d07ec3bf654add97d7872325281)
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 mips cross compiling tool for clang build
        # apt-get install binutils-mips-linux-gnu
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=mips 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

>> arch/mips/kernel/sync-r4k.c:28:6: warning: no previous prototype for function 'synchronise_count_master' [-Wmissing-prototypes]
   void synchronise_count_master(void *unused)
        ^
   arch/mips/kernel/sync-r4k.c:28:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void synchronise_count_master(void *unused)
   ^
   static 
   1 warning generated.

# https://github.com/0day-ci/linux/commit/6c760a310d6f07efede56e732f3de2e2a944e361
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Jiaxun-Yang/R4000-clock-enhancements-for-Loongson/20200817-115351
git checkout 6c760a310d6f07efede56e732f3de2e2a944e361
vim +/synchronise_count_master +28 arch/mips/kernel/sync-r4k.c

    27	
  > 28	void synchronise_count_master(void *unused)
    29	{
    30		unsigned long flags;
    31		long delta;
    32		int i;
    33	
    34		if (atomic_read(&sync_stage) != STAGE_START)
    35			BUG();
    36	
    37		local_irq_save(flags);
    38	
    39		cur_count = read_c0_count();
    40		smp_wmb();
    41		atomic_inc(&sync_stage); /* inc to STAGE_MASTER_READY */
    42	
    43		for (i = 0; i < MAX_LOOPS; i++) {
    44			cur_count = read_c0_count();
    45			smp_wmb();
    46			if (atomic_read(&sync_stage) == STAGE_SLAVE_SYNCED)
    47				break;
    48		}
    49	
    50		delta = read_c0_count() - fini_count;
    51	
    52		local_irq_restore(flags);
    53	
    54		if (i == MAX_LOOPS)
    55			pr_err("sync-r4k: Master: synchronise timeout\n");
    56		else
    57			pr_info("sync-r4k: Master: synchronise succeed, maximum delta: %ld\n", delta);
    58	
    59		return;
    60	}
    61	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

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