Re: [PATCH 2/5] sched: Split out kernel/sched/fair_balance.c from kernel/sched/fair.c

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

Hi Ingo,

kernel test robot noticed the following build warnings:

[auto build test WARNING on tip/sched/core]
[also build test WARNING on next-20240405]
[cannot apply to linux/master linus/master peterz-queue/sched/core v6.9-rc2]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Ingo-Molnar/sched-Split-out-kernel-sched-syscalls-c-from-kernel-sched-core-c/20240407-164646
base:   tip/sched/core
patch link:    https://lore.kernel.org/r/20240407084319.1462211-3-mingo%40kernel.org
patch subject: [PATCH 2/5] sched: Split out kernel/sched/fair_balance.c from kernel/sched/fair.c
config: i386-randconfig-061-20240408 (https://download.01.org/0day-ci/archive/20240408/202404080450.8XHvarcZ-lkp@intel.com/config)
compiler: gcc-13 (Ubuntu 13.2.0-4ubuntu3) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240408/202404080450.8XHvarcZ-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/202404080450.8XHvarcZ-lkp@intel.com/

sparse warnings: (new ones prefixed by >>)
>> kernel/sched/fair_balance.c:2171:40: sparse: sparse: incorrect type in initializer (different address spaces) @@     expected struct sched_domain *child @@     got struct sched_domain [noderef] __rcu *child @@
   kernel/sched/fair_balance.c:2171:40: sparse:     expected struct sched_domain *child
   kernel/sched/fair_balance.c:2171:40: sparse:     got struct sched_domain [noderef] __rcu *child
>> kernel/sched/fair_balance.c:2793:22: sparse: sparse: incompatible types in comparison expression (different address spaces):
   kernel/sched/fair_balance.c:2793:22: sparse:    struct task_struct [noderef] __rcu *
   kernel/sched/fair_balance.c:2793:22: sparse:    struct task_struct *
>> kernel/sched/fair_balance.c:4218:9: sparse: sparse: incorrect type in assignment (different address spaces) @@     expected struct sched_domain *[assigned] sd @@     got struct sched_domain [noderef] __rcu *parent @@
   kernel/sched/fair_balance.c:4218:9: sparse:     expected struct sched_domain *[assigned] sd
   kernel/sched/fair_balance.c:4218:9: sparse:     got struct sched_domain [noderef] __rcu *parent
>> kernel/sched/fair_balance.c:3866:44: sparse: sparse: incorrect type in initializer (different address spaces) @@     expected struct sched_domain *sd_parent @@     got struct sched_domain [noderef] __rcu *parent @@
   kernel/sched/fair_balance.c:3866:44: sparse:     expected struct sched_domain *sd_parent
   kernel/sched/fair_balance.c:3866:44: sparse:     got struct sched_domain [noderef] __rcu *parent
   kernel/sched/fair_balance.c:4327:9: sparse: sparse: incorrect type in assignment (different address spaces) @@     expected struct sched_domain *[assigned] sd @@     got struct sched_domain [noderef] __rcu *parent @@
   kernel/sched/fair_balance.c:4327:9: sparse:     expected struct sched_domain *[assigned] sd
   kernel/sched/fair_balance.c:4327:9: sparse:     got struct sched_domain [noderef] __rcu *parent
   kernel/sched/fair_balance.c:4972:9: sparse: sparse: incorrect type in assignment (different address spaces) @@     expected struct sched_domain *[assigned] sd @@     got struct sched_domain [noderef] __rcu *parent @@
   kernel/sched/fair_balance.c:4972:9: sparse:     expected struct sched_domain *[assigned] sd
   kernel/sched/fair_balance.c:4972:9: sparse:     got struct sched_domain [noderef] __rcu *parent
>> kernel/sched/fair_balance.c:1921:24: sparse: sparse: dereference of noderef expression
   kernel/sched/fair_balance.c:4050:64: sparse: sparse: dereference of noderef expression
   kernel/sched/fair_balance.c:4050:64: sparse: sparse: dereference of noderef expression

vim +2171 kernel/sched/fair_balance.c

  2168	
  2169	void update_group_capacity(struct sched_domain *sd, int cpu)
  2170	{
> 2171		struct sched_domain *child = sd->child;
  2172		struct sched_group *group, *sdg = sd->groups;
  2173		unsigned long capacity, min_capacity, max_capacity;
  2174		unsigned long interval;
  2175	
  2176		interval = msecs_to_jiffies(sd->balance_interval);
  2177		interval = clamp(interval, 1UL, max_load_balance_interval);
  2178		sdg->sgc->next_update = jiffies + interval;
  2179	
  2180		if (!child) {
  2181			update_cpu_capacity(sd, cpu);
  2182			return;
  2183		}
  2184	
  2185		capacity = 0;
  2186		min_capacity = ULONG_MAX;
  2187		max_capacity = 0;
  2188	
  2189		if (child->flags & SD_OVERLAP) {
  2190			/*
  2191			 * SD_OVERLAP domains cannot assume that child groups
  2192			 * span the current group.
  2193			 */
  2194	
  2195			for_each_cpu(cpu, sched_group_span(sdg)) {
  2196				unsigned long cpu_cap = capacity_of(cpu);
  2197	
  2198				capacity += cpu_cap;
  2199				min_capacity = min(cpu_cap, min_capacity);
  2200				max_capacity = max(cpu_cap, max_capacity);
  2201			}
  2202		} else  {
  2203			/*
  2204			 * !SD_OVERLAP domains can assume that child groups
  2205			 * span the current group.
  2206			 */
  2207	
  2208			group = child->groups;
  2209			do {
  2210				struct sched_group_capacity *sgc = group->sgc;
  2211	
  2212				capacity += sgc->capacity;
  2213				min_capacity = min(sgc->min_capacity, min_capacity);
  2214				max_capacity = max(sgc->max_capacity, max_capacity);
  2215				group = group->next;
  2216			} while (group != child->groups);
  2217		}
  2218	
  2219		sdg->sgc->capacity = capacity;
  2220		sdg->sgc->min_capacity = min_capacity;
  2221		sdg->sgc->max_capacity = max_capacity;
  2222	}
  2223	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki