Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965304AbbLHPbT (ORCPT ); Tue, 8 Dec 2015 10:31:19 -0500 Received: from gum.cmpxchg.org ([85.214.110.215]:48326 "EHLO gum.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965202AbbLHPbP (ORCPT ); Tue, 8 Dec 2015 10:31:15 -0500 From: Johannes Weiner To: Andrew Morton Cc: linux-mm@kvack.org, netdev@vger.kernel.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 10/14] mm: memcontrol: do not account memory+swap on unified hierarchy Date: Tue, 8 Dec 2015 10:30:20 -0500 Message-Id: <1449588624-9220-11-git-send-email-hannes@cmpxchg.org> X-Mailer: git-send-email 2.6.3 In-Reply-To: <1449588624-9220-1-git-send-email-hannes@cmpxchg.org> References: <1449588624-9220-1-git-send-email-hannes@cmpxchg.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7219 Lines: 207 The unified hierarchy memory controller doesn't expose the memory+swap counter to userspace, but its accounting is hardcoded in all charge paths right now, including the per-cpu charge cache ("the stock"). To avoid adding yet more pointless memory+swap accounting with the socket memory support in unified hierarchy, disable the counter altogether when in unified hierarchy mode. Signed-off-by: Johannes Weiner Acked-by: Michal Hocko Reviewed-by: Vladimir Davydov Acked-by: David S. Miller --- mm/memcontrol.c | 44 +++++++++++++++++++++++++------------------- 1 file changed, 25 insertions(+), 19 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 0602bee..6b8c0f7 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -87,6 +87,12 @@ int do_swap_account __read_mostly; #define do_swap_account 0 #endif +/* Whether legacy memory+swap accounting is active */ +static bool do_memsw_account(void) +{ + return !cgroup_subsys_on_dfl(memory_cgrp_subsys) && do_swap_account; +} + static const char * const mem_cgroup_stat_names[] = { "cache", "rss", @@ -1177,7 +1183,7 @@ static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) if (count < limit) margin = limit - count; - if (do_swap_account) { + if (do_memsw_account()) { count = page_counter_read(&memcg->memsw); limit = READ_ONCE(memcg->memsw.limit); if (count <= limit) @@ -1280,7 +1286,7 @@ void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) pr_cont(":"); for (i = 0; i < MEM_CGROUP_STAT_NSTATS; i++) { - if (i == MEM_CGROUP_STAT_SWAP && !do_swap_account) + if (i == MEM_CGROUP_STAT_SWAP && !do_memsw_account()) continue; pr_cont(" %s:%luKB", mem_cgroup_stat_names[i], K(mem_cgroup_read_stat(iter, i))); @@ -1903,7 +1909,7 @@ static void drain_stock(struct memcg_stock_pcp *stock) if (stock->nr_pages) { page_counter_uncharge(&old->memory, stock->nr_pages); - if (do_swap_account) + if (do_memsw_account()) page_counter_uncharge(&old->memsw, stock->nr_pages); css_put_many(&old->css, stock->nr_pages); stock->nr_pages = 0; @@ -2033,11 +2039,11 @@ retry: if (consume_stock(memcg, nr_pages)) return 0; - if (!do_swap_account || + if (!do_memsw_account() || page_counter_try_charge(&memcg->memsw, batch, &counter)) { if (page_counter_try_charge(&memcg->memory, batch, &counter)) goto done_restock; - if (do_swap_account) + if (do_memsw_account()) page_counter_uncharge(&memcg->memsw, batch); mem_over_limit = mem_cgroup_from_counter(counter, memory); } else { @@ -2124,7 +2130,7 @@ force: * temporarily by force charging it. */ page_counter_charge(&memcg->memory, nr_pages); - if (do_swap_account) + if (do_memsw_account()) page_counter_charge(&memcg->memsw, nr_pages); css_get_many(&memcg->css, nr_pages); @@ -2161,7 +2167,7 @@ static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages) return; page_counter_uncharge(&memcg->memory, nr_pages); - if (do_swap_account) + if (do_memsw_account()) page_counter_uncharge(&memcg->memsw, nr_pages); css_put_many(&memcg->css, nr_pages); @@ -2447,7 +2453,7 @@ void __memcg_kmem_uncharge(struct page *page, int order) page_counter_uncharge(&memcg->kmem, nr_pages); page_counter_uncharge(&memcg->memory, nr_pages); - if (do_swap_account) + if (do_memsw_account()) page_counter_uncharge(&memcg->memsw, nr_pages); page->mem_cgroup = NULL; @@ -3160,7 +3166,7 @@ static int memcg_stat_show(struct seq_file *m, void *v) BUILD_BUG_ON(ARRAY_SIZE(mem_cgroup_lru_names) != NR_LRU_LISTS); for (i = 0; i < MEM_CGROUP_STAT_NSTATS; i++) { - if (i == MEM_CGROUP_STAT_SWAP && !do_swap_account) + if (i == MEM_CGROUP_STAT_SWAP && !do_memsw_account()) continue; seq_printf(m, "%s %lu\n", mem_cgroup_stat_names[i], mem_cgroup_read_stat(memcg, i) * PAGE_SIZE); @@ -3182,14 +3188,14 @@ static int memcg_stat_show(struct seq_file *m, void *v) } seq_printf(m, "hierarchical_memory_limit %llu\n", (u64)memory * PAGE_SIZE); - if (do_swap_account) + if (do_memsw_account()) seq_printf(m, "hierarchical_memsw_limit %llu\n", (u64)memsw * PAGE_SIZE); for (i = 0; i < MEM_CGROUP_STAT_NSTATS; i++) { unsigned long long val = 0; - if (i == MEM_CGROUP_STAT_SWAP && !do_swap_account) + if (i == MEM_CGROUP_STAT_SWAP && !do_memsw_account()) continue; for_each_mem_cgroup_tree(mi, memcg) val += mem_cgroup_read_stat(mi, i) * PAGE_SIZE; @@ -3320,7 +3326,7 @@ static void mem_cgroup_threshold(struct mem_cgroup *memcg) { while (memcg) { __mem_cgroup_threshold(memcg, false); - if (do_swap_account) + if (do_memsw_account()) __mem_cgroup_threshold(memcg, true); memcg = parent_mem_cgroup(memcg); @@ -4466,7 +4472,7 @@ static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, * we call find_get_page() with swapper_space directly. */ page = find_get_page(swap_address_space(ent), ent.val); - if (do_swap_account) + if (do_memsw_account()) entry->val = ent.val; return page; @@ -4501,7 +4507,7 @@ static struct page *mc_handle_file_pte(struct vm_area_struct *vma, page = find_get_entry(mapping, pgoff); if (radix_tree_exceptional_entry(page)) { swp_entry_t swp = radix_to_swp_entry(page); - if (do_swap_account) + if (do_memsw_account()) *entry = swp; page = find_get_page(swap_address_space(swp), swp.val); } @@ -5276,7 +5282,7 @@ int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm, if (page->mem_cgroup) goto out; - if (do_swap_account) { + if (do_memsw_account()) { swp_entry_t ent = { .val = page_private(page), }; unsigned short id = lookup_swap_cgroup_id(ent); @@ -5340,7 +5346,7 @@ void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg, memcg_check_events(memcg, page); local_irq_enable(); - if (do_swap_account && PageSwapCache(page)) { + if (do_memsw_account() && PageSwapCache(page)) { swp_entry_t entry = { .val = page_private(page) }; /* * The swap entry might not get freed for a long time, @@ -5385,7 +5391,7 @@ static void uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout, if (!mem_cgroup_is_root(memcg)) { page_counter_uncharge(&memcg->memory, nr_pages); - if (do_swap_account) + if (do_memsw_account()) page_counter_uncharge(&memcg->memsw, nr_pages); memcg_oom_recover(memcg); } @@ -5593,7 +5599,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry) VM_BUG_ON_PAGE(PageLRU(page), page); VM_BUG_ON_PAGE(page_count(page), page); - if (!do_swap_account) + if (!do_memsw_account()) return; memcg = page->mem_cgroup; @@ -5633,7 +5639,7 @@ void mem_cgroup_uncharge_swap(swp_entry_t entry) struct mem_cgroup *memcg; unsigned short id; - if (!do_swap_account) + if (!do_memsw_account()) return; id = swap_cgroup_record(entry, 0); -- 2.6.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/