Hi Stephane,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on tip/perf/core]
[also build test WARNING on next-20210909]
[cannot apply to tip/sched/core tip/x86/core v5.14]
[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/Stephane-Eranian/perf-x86-amd-Add-AMD-Fam19h-Branch-Sampling-support/20210909-160050
base:   https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 4034fb207e302cc0b1f304084d379640c1fb1436
config: x86_64-allyesconfig (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
        # https://github.com/0day-ci/linux/commit/7ff5f8448eecfc188c2240b2a5a5ea0b00f55662
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Stephane-Eranian/perf-x86-amd-Add-AMD-Fam19h-Branch-Sampling-support/20210909-160050
        git checkout 7ff5f8448eecfc188c2240b2a5a5ea0b00f55662
        # save the attached .config to linux build tree
        make W=1 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 >>):

   arch/x86/events/amd/core.c: In function 'amd_pmu_enable_all':
>> arch/x86/events/amd/core.c:676:24: warning: variable 'hwc' set but not used [-Wunused-but-set-variable]
     676 |  struct hw_perf_event *hwc;
         |                        ^~~


vim +/hwc +676 arch/x86/events/amd/core.c

   672	
   673	static void amd_pmu_enable_all(int added)
   674	{
   675		struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
 > 676		struct hw_perf_event *hwc;
   677		int idx;
   678	
   679		for (idx = 0; idx < x86_pmu.num_counters; idx++) {
   680			hwc = &cpuc->events[idx]->hw;
   681	
   682			/* only activate events which are marked as active */
   683			if (!test_bit(idx, cpuc->active_mask))
   684				continue;
   685	
   686			amd_pmu_enable_event(cpuc->events[idx]);
   687		}
   688	}
   689	

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