arch/csky/kernel/perf_event.c:90:10: warning: no previous prototype for 'csky_pmu_read_cc'

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   1c273e10bc0cc7efb933e0ca10e260cdfc9f0b8c
commit: 0d3b051adbb72ed81956447d0d1e54d5943ee6f5 csky: Add VDSO with GENERIC_GETTIMEOFDAY, GENERIC_TIME_VSYSCALL, HAVE_GENERIC_VDSO
date:   3 weeks ago
config: csky-randconfig-r025-20210321 (attached as .config)
compiler: csky-linux-gcc (GCC) 9.3.0
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://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0d3b051adbb72ed81956447d0d1e54d5943ee6f5
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout 0d3b051adbb72ed81956447d0d1e54d5943ee6f5
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=csky 

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/csky/kernel/perf_event.c:90:10: warning: no previous prototype for 'csky_pmu_read_cc' [-Wmissing-prototypes]
      90 | uint64_t csky_pmu_read_cc(void)
         |          ^~~~~~~~~~~~~~~~
   arch/csky/kernel/perf_event.c:878:6: warning: no previous prototype for 'csky_pmu_event_set_period' [-Wmissing-prototypes]
     878 | int  csky_pmu_event_set_period(struct perf_event *event)
         |      ^~~~~~~~~~~~~~~~~~~~~~~~~
   arch/csky/kernel/perf_event.c:1198:5: warning: no previous prototype for 'init_hw_perf_events' [-Wmissing-prototypes]
    1198 | int init_hw_perf_events(void)
         |     ^~~~~~~~~~~~~~~~~~~
   arch/csky/kernel/perf_event.c:1293:5: warning: no previous prototype for 'csky_pmu_device_probe' [-Wmissing-prototypes]
    1293 | int csky_pmu_device_probe(struct platform_device *pdev,
         |     ^~~~~~~~~~~~~~~~~~~~~


vim +/csky_pmu_read_cc +90 arch/csky/kernel/perf_event.c

    88	
    89	/* cycle counter */
  > 90	uint64_t csky_pmu_read_cc(void)
    91	{
    92		uint32_t lo, hi, tmp;
    93		uint64_t result;
    94	
    95		do {
    96			tmp = cprgr("<0, 0x3>");
    97			lo  = cprgr("<0, 0x2>");
    98			hi  = cprgr("<0, 0x3>");
    99		} while (hi != tmp);
   100	
   101		result = (uint64_t) (hi) << 32;
   102		result |= lo;
   103	
   104		return result;
   105	}
   106	

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

Attachment: .config.gz
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