Hi Johannes, Below is a 0day report from a build with Clang, can you please take a look? On Fri, Nov 15, 2019 at 1:44 PM kbuild test robot <lkp@xxxxxxxxx> wrote: > > CC: kbuild-all@xxxxxxxxxxxx > TO: Johannes Weiner <hannes@xxxxxxxxxxx> > CC: Suren Baghdasaryan <surenb@xxxxxxxxxx> > CC: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > CC: Linux Memory Management List <linux-mm@xxxxxxxxx> > > tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master > head: 5a6fcbeabe3e20459ed8504690b2515dacc5246f > commit: 07976d367592d6613370c93706795b4ebc0850f1 [11878/12136] mm: vmscan: enforce inactive:active ratio at the reclaim root > config: arm64-defconfig (attached as .config) > compiler: clang version 10.0.0 (git://gitmirror/llvm_project f7e9d81a8e222f3c9d4f57e0817f19bbb795e5b6) > reproduce: > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross > chmod +x ~/bin/make.cross > git checkout 07976d367592d6613370c93706795b4ebc0850f1 > # save the attached .config to linux build tree > make.cross ARCH=arm64 > > If you fix the issue, kindly add following tag > Reported-by: kbuild test robot <lkp@xxxxxxxxx> > > All warnings (new ones prefixed by >>): > > >> mm/vmscan.c:2216:39: warning: implicit conversion from enumeration type 'enum lru_list' to different enumeration type 'enum node_stat_item' [-Wenum-conversion] > inactive = lruvec_page_state(lruvec, inactive_lru); > ~~~~~~~~~~~~~~~~~ ^~~~~~~~~~~~ > mm/vmscan.c:2217:37: warning: implicit conversion from enumeration type 'enum lru_list' to different enumeration type 'enum node_stat_item' [-Wenum-conversion] > active = lruvec_page_state(lruvec, active_lru); > ~~~~~~~~~~~~~~~~~ ^~~~~~~~~~ > mm/vmscan.c:2746:42: warning: implicit conversion from enumeration type 'enum lru_list' to different enumeration type 'enum node_stat_item' [-Wenum-conversion] > file = lruvec_page_state(target_lruvec, LRU_INACTIVE_FILE); > ~~~~~~~~~~~~~~~~~ ^~~~~~~~~~~~~~~~~ > 3 warnings generated. > > vim +2216 mm/vmscan.c > > 2180 > 2181 /* > 2182 * The inactive anon list should be small enough that the VM never has > 2183 * to do too much work. > 2184 * > 2185 * The inactive file list should be small enough to leave most memory > 2186 * to the established workingset on the scan-resistant active list, > 2187 * but large enough to avoid thrashing the aggregate readahead window. > 2188 * > 2189 * Both inactive lists should also be large enough that each inactive > 2190 * page has a chance to be referenced again before it is reclaimed. > 2191 * > 2192 * If that fails and refaulting is observed, the inactive list grows. > 2193 * > 2194 * The inactive_ratio is the target ratio of ACTIVE to INACTIVE pages > 2195 * on this LRU, maintained by the pageout code. An inactive_ratio > 2196 * of 3 means 3:1 or 25% of the pages are kept on the inactive list. > 2197 * > 2198 * total target max > 2199 * memory ratio inactive > 2200 * ------------------------------------- > 2201 * 10MB 1 5MB > 2202 * 100MB 1 50MB > 2203 * 1GB 3 250MB > 2204 * 10GB 10 0.9GB > 2205 * 100GB 31 3GB > 2206 * 1TB 101 10GB > 2207 * 10TB 320 32GB > 2208 */ > 2209 static bool inactive_is_low(struct lruvec *lruvec, enum lru_list inactive_lru) > 2210 { > 2211 enum lru_list active_lru = inactive_lru + LRU_ACTIVE; > 2212 unsigned long inactive, active; > 2213 unsigned long inactive_ratio; > 2214 unsigned long gb; > 2215 > > 2216 inactive = lruvec_page_state(lruvec, inactive_lru); > 2217 active = lruvec_page_state(lruvec, active_lru); Look like lruvec_page_state() defined in include/linux/memcontrol.h takes an `enum node_stat_item` for its second parameter, but `enum lru_list`'s are being passed instead? I see what's going on with the definitions, but a function should be used to safely convert between the two different enums in case their definitions ever change, otherwise we'll continue to see this warning. > 2218 > 2219 gb = (inactive + active) >> (30 - PAGE_SHIFT); > 2220 if (gb) > 2221 inactive_ratio = int_sqrt(10 * gb); > 2222 else > 2223 inactive_ratio = 1; > 2224 > 2225 return inactive * inactive_ratio < active; > 2226 } > 2227 > > --- > 0-DAY kernel test infrastructure Open Source Technology Center > https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx Intel Corporation -- Thanks, ~Nick Desaulniers
