[morse:mpam/snapshot/v6.16-rc5 62/80] drivers/platform/arm64/mpam/mpam_resctrl.c:355:2: warning: unannotated fall-through between switch labels

[kernel test robot <lkp@intel.com>]

Hi James,

First bad commit (maybe != root cause):

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux.git mpam/snapshot/v6.16-rc5
head:   b8e4905233fe45814b3c73be7e091f172cfb86ce
commit: 85cb8b2e516cf17f31528573039c63f42242ba81 [62/80] arm64: mpam: Select ARCH_HAS_CPU_RESCTRL
config: arm64-allmodconfig (https://download.01.org/0day-ci/archive/20250719/202507192146.RlGCE0mv-lkp@intel.com/config)
compiler: clang version 19.1.7 (https://github.com/llvm/llvm-project cd708029e0b2869e80abe31ddb175f7c35361f90)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250719/202507192146.RlGCE0mv-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/202507192146.RlGCE0mv-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/platform/arm64/mpam/mpam_resctrl.c:355:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
     355 |         default:
         |         ^
   drivers/platform/arm64/mpam/mpam_resctrl.c:355:2: note: insert '__attribute__((fallthrough));' to silence this warning
     355 |         default:
         |         ^
         |         __attribute__((fallthrough)); 
   drivers/platform/arm64/mpam/mpam_resctrl.c:355:2: note: insert 'break;' to avoid fall-through
     355 |         default:
         |         ^
         |         break; 
   1 warning generated.


vim +355 drivers/platform/arm64/mpam/mpam_resctrl.c

72793604c0b57a James Morse 2021-06-25  333  
72793604c0b57a James Morse 2021-06-25  334  static void resctrl_arch_mon_ctx_free_no_wait(enum resctrl_event_id evtid,
72793604c0b57a James Morse 2021-06-25  335  					      u32 mon_idx)
72793604c0b57a James Morse 2021-06-25  336  {
72793604c0b57a James Morse 2021-06-25  337  	struct mpam_resctrl_mon *mon = &mpam_resctrl_counters[evtid];
72793604c0b57a James Morse 2021-06-25  338  
72793604c0b57a James Morse 2021-06-25  339  	if (!mon->class)
72793604c0b57a James Morse 2021-06-25  340  		return;
72793604c0b57a James Morse 2021-06-25  341  
72793604c0b57a James Morse 2021-06-25  342  	switch (evtid) {
72793604c0b57a James Morse 2021-06-25  343  	case QOS_L3_OCCUP_EVENT_ID:
72793604c0b57a James Morse 2021-06-25  344  		mpam_free_csu_mon(mon->class, mon_idx);
72793604c0b57a James Morse 2021-06-25  345  		wake_up(&resctrl_mon_ctx_waiters);
72793604c0b57a James Morse 2021-06-25  346  		return;
72793604c0b57a James Morse 2021-06-25  347  	case QOS_L3_MBM_TOTAL_EVENT_ID:
72793604c0b57a James Morse 2021-06-25  348  	case QOS_L3_MBM_LOCAL_EVENT_ID:
72793604c0b57a James Morse 2021-06-25  349  		if (mpam_monitors_free_running()) {
72793604c0b57a James Morse 2021-06-25  350  			WARN_ON_ONCE(mon_idx != USE_RMID_IDX);
72793604c0b57a James Morse 2021-06-25  351  			return;
72793604c0b57a James Morse 2021-06-25  352  		}
72793604c0b57a James Morse 2021-06-25  353  		mpam_free_mbwu_mon(mon->class, mon_idx);
72793604c0b57a James Morse 2021-06-25  354  		wake_up(&resctrl_mon_ctx_waiters);
72793604c0b57a James Morse 2021-06-25 @355  	default:
72793604c0b57a James Morse 2021-06-25  356  	case QOS_NUM_EVENTS:
72793604c0b57a James Morse 2021-06-25  357  		return;
72793604c0b57a James Morse 2021-06-25  358  	}
72793604c0b57a James Morse 2021-06-25  359  }
72793604c0b57a James Morse 2021-06-25  360  

:::::: The code at line 355 was first introduced by commit
:::::: 72793604c0b57a141ee01f1caac2b5abe4c31f10 arm_mpam: resctrl: Allow resctrl to allocate monitors

:::::: TO: James Morse <james.morse@arm.com>
:::::: CC: James Morse <james.morse@arm.com>

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