Re: [PATCH 3/3] mm: memcontrol: correct the nr_pages parameter type of mem_cgroup_update_lru_size()

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

Hi Qi,

kernel test robot noticed the following build warnings:

[auto build test WARNING on akpm-mm/mm-everything]
[also build test WARNING on next-20260325]
[cannot apply to trace/for-next linus/master v7.0-rc5]
[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/Qi-Zheng/mm-memcontrol-correct-the-type-of-stats_updates-to-unsigned-long/20260325-230337
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/2cf06f9faf51900ce6acbb4740fc60355a2842ed.1774342371.git.zhengqi.arch%40bytedance.com
patch subject: [PATCH 3/3] mm: memcontrol: correct the nr_pages parameter type of mem_cgroup_update_lru_size()
config: riscv-allnoconfig-bpf (https://download.01.org/0day-ci/archive/20260326/202603260338.GfCrsaVO-lkp@intel.com/config)
compiler: riscv64-linux-gnu-gcc (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260326/202603260338.GfCrsaVO-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/202603260338.GfCrsaVO-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from ./arch/riscv/include/asm/bug.h:90,
                    from ./include/linux/bug.h:5,
                    from ./arch/riscv/include/asm/cmpxchg.h:9,
                    from ./arch/riscv/include/asm/barrier.h:14,
                    from ./include/linux/list.h:11,
                    from ./include/linux/cgroup-defs.h:12,
                    from mm/memcontrol.c:28:
   mm/memcontrol.c: In function 'mem_cgroup_update_lru_size':
>> mm/memcontrol.c:1486:17: warning: format '%d' expects argument of type 'int', but argument 5 has type 'long int' [-Wformat=]
    1486 |                 "%s(%p, %d, %d): lru_size %ld\n",
         |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    1487 |                 __func__, lruvec, lru, nr_pages, size)) {
         |                                        ~~~~~~~~
         |                                        |
         |                                        long int
   ./include/asm-generic/bug.h:133:31: note: in definition of macro '__WARN_printf'
     133 |                 __warn_printk(arg);                                     \
         |                               ^~~
   ./include/linux/once_lite.h:31:25: note: in expansion of macro 'WARN'
      31 |                         func(__VA_ARGS__);                              \
         |                         ^~~~
   ./include/asm-generic/bug.h:185:9: note: in expansion of macro 'DO_ONCE_LITE_IF'
     185 |         DO_ONCE_LITE_IF(condition, WARN, 1, format)
         |         ^~~~~~~~~~~~~~~
   mm/memcontrol.c:1485:13: note: in expansion of macro 'WARN_ONCE'
    1485 |         if (WARN_ONCE(size < 0,
         |             ^~~~~~~~~
   mm/memcontrol.c:1486:30: note: format string is defined here
    1486 |                 "%s(%p, %d, %d): lru_size %ld\n",
         |                             ~^
         |                              |
         |                              int
         |                             %ld


vim +1486 mm/memcontrol.c

6168d0da2b479ce Alex Shi           2020-12-15  1457  
925b7673cce3911 Johannes Weiner    2012-01-12  1458  /**
fa9add641b1b1c5 Hugh Dickins       2012-05-29  1459   * mem_cgroup_update_lru_size - account for adding or removing an lru page
fa9add641b1b1c5 Hugh Dickins       2012-05-29  1460   * @lruvec: mem_cgroup per zone lru vector
fa9add641b1b1c5 Hugh Dickins       2012-05-29  1461   * @lru: index of lru list the page is sitting on
b4536f0c829c858 Michal Hocko       2017-01-10  1462   * @zid: zone id of the accounted pages
fa9add641b1b1c5 Hugh Dickins       2012-05-29  1463   * @nr_pages: positive when adding or negative when removing
925b7673cce3911 Johannes Weiner    2012-01-12  1464   *
ca707239e8a7958 Hugh Dickins       2016-05-19  1465   * This function must be called under lru_lock, just before a page is added
07ca760673088f2 Hugh Dickins       2022-02-14  1466   * to or just after a page is removed from an lru list.
925b7673cce3911 Johannes Weiner    2012-01-12  1467   */
fa9add641b1b1c5 Hugh Dickins       2012-05-29  1468  void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
6a3cda9fd4d0f0b Qi Zheng           2026-03-24  1469  				int zid, long nr_pages)
08e552c69c6930d KAMEZAWA Hiroyuki  2009-01-07  1470  {
ef8f2327996b5c2 Mel Gorman         2016-07-28  1471  	struct mem_cgroup_per_node *mz;
fa9add641b1b1c5 Hugh Dickins       2012-05-29  1472  	unsigned long *lru_size;
ca707239e8a7958 Hugh Dickins       2016-05-19  1473  	long size;
08e552c69c6930d KAMEZAWA Hiroyuki  2009-01-07  1474  
f8d665422603ee1 Hirokazu Takahashi 2009-01-07  1475  	if (mem_cgroup_disabled())
08e552c69c6930d KAMEZAWA Hiroyuki  2009-01-07  1476  		return;
6d12e2d8ddbe653 KAMEZAWA Hiroyuki  2008-02-07  1477  
ef8f2327996b5c2 Mel Gorman         2016-07-28  1478  	mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
b4536f0c829c858 Michal Hocko       2017-01-10  1479  	lru_size = &mz->lru_zone_size[zid][lru];
ca707239e8a7958 Hugh Dickins       2016-05-19  1480  
ca707239e8a7958 Hugh Dickins       2016-05-19  1481  	if (nr_pages < 0)
ca707239e8a7958 Hugh Dickins       2016-05-19  1482  		*lru_size += nr_pages;
ca707239e8a7958 Hugh Dickins       2016-05-19  1483  
ca707239e8a7958 Hugh Dickins       2016-05-19  1484  	size = *lru_size;
b4536f0c829c858 Michal Hocko       2017-01-10  1485  	if (WARN_ONCE(size < 0,
b4536f0c829c858 Michal Hocko       2017-01-10 @1486  		"%s(%p, %d, %d): lru_size %ld\n",
b4536f0c829c858 Michal Hocko       2017-01-10  1487  		__func__, lruvec, lru, nr_pages, size)) {
ca707239e8a7958 Hugh Dickins       2016-05-19  1488  		VM_BUG_ON(1);
ca707239e8a7958 Hugh Dickins       2016-05-19  1489  		*lru_size = 0;
ca707239e8a7958 Hugh Dickins       2016-05-19  1490  	}
ca707239e8a7958 Hugh Dickins       2016-05-19  1491  
ca707239e8a7958 Hugh Dickins       2016-05-19  1492  	if (nr_pages > 0)
fa9add641b1b1c5 Hugh Dickins       2012-05-29  1493  		*lru_size += nr_pages;
08e552c69c6930d KAMEZAWA Hiroyuki  2009-01-07  1494  }
544122e5e0ee27d KAMEZAWA Hiroyuki  2009-01-07  1495  

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