Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752896AbaJTPWY (ORCPT ); Mon, 20 Oct 2014 11:22:24 -0400 Received: from gum.cmpxchg.org ([85.214.110.215]:42363 "EHLO gum.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752612AbaJTPWW (ORCPT ); Mon, 20 Oct 2014 11:22:22 -0400 From: Johannes Weiner To: Andrew Morton Cc: Hugh Dickins , Michal Hocko , Vladimir Davydov , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [patch 2/4] mm: memcontrol: remove unnecessary PCG_MEMSW memory+swap charge flag Date: Mon, 20 Oct 2014 11:22:10 -0400 Message-Id: <1413818532-11042-3-git-send-email-hannes@cmpxchg.org> X-Mailer: git-send-email 2.1.2 In-Reply-To: <1413818532-11042-1-git-send-email-hannes@cmpxchg.org> References: <1413818532-11042-1-git-send-email-hannes@cmpxchg.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Now that mem_cgroup_swapout() fully uncharges the page, every page that is still in use when reaching mem_cgroup_uncharge() is known to carry both the memory and the memory+swap charge. Simplify the uncharge path and remove the PCG_MEMSW page flag accordingly. Signed-off-by: Johannes Weiner --- include/linux/page_cgroup.h | 1 - mm/memcontrol.c | 34 ++++++++++++---------------------- 2 files changed, 12 insertions(+), 23 deletions(-) diff --git a/include/linux/page_cgroup.h b/include/linux/page_cgroup.h index 5c831f1eca79..da62ee2be28b 100644 --- a/include/linux/page_cgroup.h +++ b/include/linux/page_cgroup.h @@ -5,7 +5,6 @@ enum { /* flags for mem_cgroup */ PCG_USED = 0x01, /* This page is charged to a memcg */ PCG_MEM = 0x02, /* This page holds a memory charge */ - PCG_MEMSW = 0x04, /* This page holds a memory+swap charge */ }; struct pglist_data; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 7709f17347f3..9bab35fc3e9e 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2606,7 +2606,7 @@ static void commit_charge(struct page *page, struct mem_cgroup *memcg, * have the page locked */ pc->mem_cgroup = memcg; - pc->flags = PCG_USED | PCG_MEM | (do_swap_account ? PCG_MEMSW : 0); + pc->flags = PCG_USED | PCG_MEM; if (lrucare) unlock_page_lru(page, isolated); @@ -5815,7 +5815,6 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry) if (!PageCgroupUsed(pc)) return; - VM_BUG_ON_PAGE(!(pc->flags & PCG_MEMSW), page); memcg = pc->mem_cgroup; oldid = swap_cgroup_record(entry, mem_cgroup_id(memcg)); @@ -6010,17 +6009,16 @@ void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg) } static void uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout, - unsigned long nr_mem, unsigned long nr_memsw, unsigned long nr_anon, unsigned long nr_file, unsigned long nr_huge, struct page *dummy_page) { + unsigned long nr_pages = nr_anon + nr_file; unsigned long flags; if (!mem_cgroup_is_root(memcg)) { - if (nr_mem) - page_counter_uncharge(&memcg->memory, nr_mem); - if (nr_memsw) - page_counter_uncharge(&memcg->memsw, nr_memsw); + page_counter_uncharge(&memcg->memory, nr_pages); + if (do_swap_account) + page_counter_uncharge(&memcg->memsw, nr_pages); memcg_oom_recover(memcg); } @@ -6029,23 +6027,21 @@ static void uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout, __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_CACHE], nr_file); __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS_HUGE], nr_huge); __this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT], pgpgout); - __this_cpu_add(memcg->stat->nr_page_events, nr_anon + nr_file); + __this_cpu_add(memcg->stat->nr_page_events, nr_pages); memcg_check_events(memcg, dummy_page); local_irq_restore(flags); if (!mem_cgroup_is_root(memcg)) - css_put_many(&memcg->css, max(nr_mem, nr_memsw)); + css_put_many(&memcg->css, nr_pages); } static void uncharge_list(struct list_head *page_list) { struct mem_cgroup *memcg = NULL; - unsigned long nr_memsw = 0; unsigned long nr_anon = 0; unsigned long nr_file = 0; unsigned long nr_huge = 0; unsigned long pgpgout = 0; - unsigned long nr_mem = 0; struct list_head *next; struct page *page; @@ -6072,10 +6068,9 @@ static void uncharge_list(struct list_head *page_list) if (memcg != pc->mem_cgroup) { if (memcg) { - uncharge_batch(memcg, pgpgout, nr_mem, nr_memsw, - nr_anon, nr_file, nr_huge, page); - pgpgout = nr_mem = nr_memsw = 0; - nr_anon = nr_file = nr_huge = 0; + uncharge_batch(memcg, pgpgout, nr_anon, nr_file, + nr_huge, page); + pgpgout = nr_anon = nr_file = nr_huge = 0; } memcg = pc->mem_cgroup; } @@ -6091,18 +6086,14 @@ static void uncharge_list(struct list_head *page_list) else nr_file += nr_pages; - if (pc->flags & PCG_MEM) - nr_mem += nr_pages; - if (pc->flags & PCG_MEMSW) - nr_memsw += nr_pages; pc->flags = 0; pgpgout++; } while (next != page_list); if (memcg) - uncharge_batch(memcg, pgpgout, nr_mem, nr_memsw, - nr_anon, nr_file, nr_huge, page); + uncharge_batch(memcg, pgpgout, nr_anon, nr_file, + nr_huge, page); } /** @@ -6187,7 +6178,6 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage, return; VM_BUG_ON_PAGE(!(pc->flags & PCG_MEM), oldpage); - VM_BUG_ON_PAGE(do_swap_account && !(pc->flags & PCG_MEMSW), oldpage); if (lrucare) lock_page_lru(oldpage, &isolated); -- 2.1.2 -- 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/