Hi Yafang, Thank you for the patch! Yet something to improve: [auto build test ERROR on linus/master] [also build test ERROR on v5.5-rc3 next-20191219] [cannot apply to mmotm/master] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Yafang-Shao/protect-page-cache-f... base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 46cf053efec6a3a5f343fead837777efe8252a46 config: um-x86_64_defconfig (attached as .config) compiler: gcc-7 (Debian 7.5.0-3) 7.5.0 reproduce: # save the attached .config to linux build tree make ARCH=um SUBARCH=x86_64 If you fix the issue, kindly add following tag Reported-by: kbuild test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): In file included from include/linux/swap.h:9:0, from mm/vmscan.c:22: include/linux/memcontrol.h:872:23: error: conflicting types for 'memcg' struct inode *memcg) ^~~~~ include/linux/memcontrol.h:871:63: note: previous definition of 'memcg' was here static inline bool memcg_can_reclaim_inode(struct mem_cgroup *memcg, ^~~~~ mm/vmscan.c: In function 'shrink_node_memcgs': memcg->in_low_reclaim = 1; ^~ -- In file included from include/linux/swap.h:9:0, from fs/inode.c:11: include/linux/memcontrol.h:872:23: error: conflicting types for 'memcg' struct inode *memcg) ^~~~~ include/linux/memcontrol.h:871:63: note: previous definition of 'memcg' was here static inline bool memcg_can_reclaim_inode(struct mem_cgroup *memcg, ^~~~~ fs/inode.c: In function 'prune_icache_sb': ihead.memcg = sc->memcg; ^ vim +2670 mm/vmscan.c 2639 2640 static void shrink_node_memcgs(pg_data_t *pgdat, struct scan_control *sc) 2641 { 2642 struct mem_cgroup *target_memcg = sc->target_mem_cgroup; 2643 struct mem_cgroup *memcg; 2644 2645 memcg = mem_cgroup_iter(target_memcg, NULL, NULL); 2646 do { 2647 struct lruvec *lruvec = mem_cgroup_lruvec(memcg, pgdat); 2648 unsigned long reclaimed; 2649 unsigned long scanned; 2650 2651 switch (mem_cgroup_protected(target_memcg, memcg)) { 2652 case MEMCG_PROT_MIN: 2653 /* 2654 * Hard protection. 2655 * If there is no reclaimable memory, OOM. 2656 */ 2657 continue; 2658 case MEMCG_PROT_LOW: 2659 /* 2660 * Soft protection. 2661 * Respect the protection only as long as 2662 * there is an unprotected supply 2663 * of reclaimable memory from other cgroups. 2664 */ 2665 if (!sc->memcg_low_reclaim) { 2666 sc->memcg_low_skipped = 1; 2667 continue; 2668 } 2669 2671 memcg_memory_event(memcg, MEMCG_LOW); 2672 break; 2673 case MEMCG_PROT_NONE: 2674 /* 2675 * All protection thresholds breached. We may 2676 * still choose to vary the scan pressure 2677 * applied based on by how much the cgroup in 2678 * question has exceeded its protection 2679 * thresholds (see get_scan_count). 2680 */ 2681 break; 2682 case MEMCG_PROT_SKIP: 2683 /* 2684 * Skip scanning this memcg if the usage of it is 2685 * zero. 2686 */ 2687 continue; 2688 } 2689 2690 reclaimed = sc->nr_reclaimed; 2691 scanned = sc->nr_scanned; 2692 2693 shrink_lruvec(lruvec, sc); 2694 2695 shrink_slab(sc->gfp_mask, pgdat->node_id, memcg, 2696 sc->priority); 2697 2698 if (memcg->in_low_reclaim) 2699 memcg->in_low_reclaim = 0; 2700 2701 /* Record the group's reclaim efficiency */ 2702 vmpressure(sc->gfp_mask, memcg, false, 2703 sc->nr_scanned - scanned, 2704 sc->nr_reclaimed - reclaimed); 2705 2706 } while ((memcg = mem_cgroup_iter(target_memcg, memcg, NULL))); 2707 } 2708 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation