The patch titled Subject: memcg: only check memcg_kmem_skip_account in __memcg_kmem_get_cache has been removed from the -mm tree. Its filename was memcg-only-check-memcg_kmem_skip_account-in-__memcg_kmem_get_cache.patch This patch was dropped because it was withdrawn ------------------------------------------------------ From: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx> Subject: memcg: only check memcg_kmem_skip_account in __memcg_kmem_get_cache __memcg_kmem_get_cache can recurse if it calls kmalloc (which it does if the cgroup's kmem cache doesn't exist), because kmalloc may call __memcg_kmem_get_cache internally again. To avoid the recursion, we use the task_struct->memcg_kmem_skip_account flag. However, there's no need in checking the flag in memcg_kmem_newpage_charge or memcg_kmem_recharge_slab, because there's no way how these two functions could result in recursion, if called from memcg_kmem_get_cache. So let's remove the redundant code. Signed-off-by: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memcontrol.c | 31 ------------------------------- 1 file changed, 31 deletions(-) diff -puN mm/memcontrol.c~memcg-only-check-memcg_kmem_skip_account-in-__memcg_kmem_get_cache mm/memcontrol.c --- a/mm/memcontrol.c~memcg-only-check-memcg_kmem_skip_account-in-__memcg_kmem_get_cache +++ a/mm/memcontrol.c @@ -2717,34 +2717,6 @@ __memcg_kmem_newpage_charge(gfp_t gfp, s *_memcg = NULL; - /* - * Disabling accounting is only relevant for some specific memcg - * internal allocations. Therefore we would initially not have such - * check here, since direct calls to the page allocator that are - * accounted to kmemcg (alloc_kmem_pages and friends) only happen - * outside memcg core. We are mostly concerned with cache allocations, - * and by having this test at memcg_kmem_get_cache, we are already able - * to relay the allocation to the root cache and bypass the memcg cache - * altogether. - * - * There is one exception, though: the SLUB allocator does not create - * large order caches, but rather service large kmallocs directly from - * the page allocator. Therefore, the following sequence when backed by - * the SLUB allocator: - * - * memcg_stop_kmem_account(); - * kmalloc(<large_number>) - * memcg_resume_kmem_account(); - * - * would effectively ignore the fact that we should skip accounting, - * since it will drive us directly to this function without passing - * through the cache selector memcg_kmem_get_cache. Such large - * allocations are extremely rare but can happen, for instance, for the - * cache arrays. We bring this test here. - */ - if (current->memcg_kmem_skip_account) - return true; - memcg = get_mem_cgroup_from_mm(current->mm); if (!memcg_kmem_is_active(memcg)) { @@ -2800,9 +2772,6 @@ int __memcg_kmem_recharge_slab(void *obj int nr_pages; int ret = 0; - if (current->memcg_kmem_skip_account) - goto out; - page = virt_to_head_page(obj); page_memcg = ACCESS_ONCE(page->mem_cgroup); _ Patches currently in -mm which might be from vdavydov@xxxxxxxxxxxxx are slab-print-slabinfo-header-in-seq-show.patch mm-memcontrol-lockless-page-counters.patch mm-hugetlb_cgroup-convert-to-lockless-page-counters.patch kernel-res_counter-remove-the-unused-api.patch kernel-res_counter-remove-the-unused-api-fix.patch mm-memcontrol-convert-reclaim-iterator-to-simple-css-refcounting.patch mm-memcontrol-take-a-css-reference-for-each-charged-page.patch mm-memcontrol-remove-obsolete-kmemcg-pinning-tricks.patch mm-memcontrol-continue-cache-reclaim-from-offlined-groups.patch mm-memcontrol-remove-synchroneous-stock-draining-code.patch mm-introduce-single-zone-pcplists-drain.patch mm-page_isolation-drain-single-zone-pcplists.patch mm-cma-drain-single-zone-pcplists.patch mm-memory_hotplug-failure-drain-single-zone-pcplists.patch memcg-simplify-unreclaimable-groups-handling-in-soft-limit-reclaim.patch memcg-remove-activate_kmem_mutex.patch mm-memcontrol-micro-optimize-mem_cgroup_split_huge_fixup.patch mm-memcontrol-uncharge-pages-on-swapout.patch mm-memcontrol-uncharge-pages-on-swapout-fix.patch mm-memcontrol-remove-unnecessary-pcg_memsw-memoryswap-charge-flag.patch mm-memcontrol-remove-unnecessary-pcg_mem-memory-charge-flag.patch mm-memcontrol-remove-unnecessary-pcg_used-pc-mem_cgroup-valid-flag.patch mm-memcontrol-remove-unnecessary-pcg_used-pc-mem_cgroup-valid-flag-fix.patch mm-memcontrol-inline-memcg-move_lock-locking.patch mm-memcontrol-dont-pass-a-null-memcg-to-mem_cgroup_end_move.patch mm-memcontrol-fold-mem_cgroup_start_move-mem_cgroup_end_move.patch mm-memcontrol-fold-mem_cgroup_start_move-mem_cgroup_end_move-fix.patch memcg-remove-mem_cgroup_reclaimable-check-from-soft-reclaim.patch memcg-use-generic-slab-iterators-for-showing-slabinfo.patch mm-memcontrol-shorten-the-page-statistics-update-slowpath.patch mm-memcontrol-remove-bogus-null-check-after-mem_cgroup_from_task.patch mm-memcontrol-pull-the-null-check-from-__mem_cgroup_same_or_subtree.patch mm-memcontrol-drop-bogus-rcu-locking-from-mem_cgroup_same_or_subtree.patch mm-embed-the-memcg-pointer-directly-into-struct-page.patch mm-embed-the-memcg-pointer-directly-into-struct-page-fix.patch mm-page_cgroup-rename-file-to-mm-swap_cgroupc.patch mm-move-page-mem_cgroup-bad-page-handling-into-generic-code.patch mm-move-page-mem_cgroup-bad-page-handling-into-generic-code-fix.patch mm-move-page-mem_cgroup-bad-page-handling-into-generic-code-fix-2.patch memcg-__mem_cgroup_free-remove-stale-disarm_static_keys-comment.patch memcg-dont-check-mm-in-__memcg_kmem_get_cachenewpage_charge.patch memcg-do-not-abuse-memcg_kmem_skip_account.patch linux-next.patch slab-fix-cpuset-check-in-fallback_alloc.patch slub-fix-cpuset-check-in-get_any_partial.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html