Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753914Ab0G0IA1 (ORCPT ); Tue, 27 Jul 2010 04:00:27 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:58801 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753588Ab0G0IAZ (ORCPT ); Tue, 27 Jul 2010 04:00:25 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Date: Tue, 27 Jul 2010 16:55:32 +0900 From: KAMEZAWA Hiroyuki To: KAMEZAWA Hiroyuki Cc: "linux-mm@kvack.org" , "nishimura@mxp.nes.nec.co.jp" , "balbir@linux.vnet.ibm.com" , gthelen@google.com, m-ikeda@ds.jp.nec.com, "akpm@linux-foundation.org" , "linux-kernel@vger.kernel.org" Subject: [RFC][PATCH 3/7][memcg] memcg on virt array for quick access via ID. Message-Id: <20100727165532.24a07473.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20100727165155.8b458b7f.kamezawa.hiroyu@jp.fujitsu.com> References: <20100727165155.8b458b7f.kamezawa.hiroyu@jp.fujitsu.com> Organization: FUJITSU Co. LTD. X-Mailer: Sylpheed 3.0.3 (GTK+ 2.10.14; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7588 Lines: 250 From: KAMEZAWA Hiroyuki Now, memory cgroup has an ID(1-65535) per a group and use it for walking hierarchy, recording it for swapped-out resources etc... This patch tries to make use of it more. Allocating memory cgroup into an (virtual) array. This allows to access a memory cgroup by mem = mem_cgroup_base + id. By this, we don't have to use css_lookup() and will have a chance to replace a pointer to mem_cgroup(8bytes on 64bit) to an ID (2bytes). Thought: - Although I added CONFIG in this patch, I wonder I should remove it.. Signed-off-by: KAMEZAWA Hiroyuki --- init/Kconfig | 14 +++++++- mm/memcontrol.c | 93 ++++++++++++++++++++++++++++++-------------------------- 2 files changed, 63 insertions(+), 44 deletions(-) Index: mmotm-0719/init/Kconfig =================================================================== --- mmotm-0719.orig/init/Kconfig +++ mmotm-0719/init/Kconfig @@ -555,7 +555,7 @@ config RESOURCE_COUNTERS config CGROUP_MEM_RES_CTLR bool "Memory Resource Controller for Control Groups" - depends on CGROUPS && RESOURCE_COUNTERS + depends on CGROUPS && RESOURCE_COUNTERS && MMU select MM_OWNER help Provides a memory resource controller that manages both anonymous @@ -594,6 +594,18 @@ config CGROUP_MEM_RES_CTLR_SWAP Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page size is 4096bytes, 512k per 1Gbytes of swap. +config MEM_CGROUP_MAX_GROUPS + int "Maximum number of memory cgroups on a system" + range 1 65535 if 64BIT + default 8192 if 64BIT + range 1 4096 if 32BIT + default 2048 if 32BIT + help + Memory cgroup has limitation of the number of groups created. + Please select your favorite value. The more you allow, the more + memory will be consumed. This consumes vmalloc() area, so, + this should be small on 32bit arch. + menuconfig CGROUP_SCHED bool "Group CPU scheduler" depends on EXPERIMENTAL && CGROUPS Index: mmotm-0719/mm/memcontrol.c =================================================================== --- mmotm-0719.orig/mm/memcontrol.c +++ mmotm-0719/mm/memcontrol.c @@ -48,6 +48,7 @@ #include #include #include +#include #include "internal.h" #include @@ -242,7 +243,8 @@ struct mem_cgroup { /* For oom notifier event fd */ struct list_head oom_notify; - + /* Used when varray is used */ + int custom_id; /* * Should we move charges of a task when a task is moved into this * mem_cgroup ? And what type of charges should we move ? @@ -254,6 +256,8 @@ struct mem_cgroup { struct mem_cgroup_stat_cpu *stat; }; +static struct mem_cgroup *mem_cgroup_base __read_mostly; + /* Stuffs for move charges at task migration. */ /* * Types of charges to be moved. "move_charge_at_immitgrate" is treated as a @@ -341,6 +345,19 @@ static void mem_cgroup_put(struct mem_cg static struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *mem); static void drain_all_stock_async(void); +/* + * A helper function to get mem_cgroup from ID. must be called under + * rcu_read_lock(). The caller must check css_is_removed() or some if + * it's concern. (dropping refcnt from swap can be called against removed + * memcg.) + */ +static struct mem_cgroup *id_to_mem(unsigned short id) +{ + if (id) + return mem_cgroup_base + id; + return NULL; +} + static struct mem_cgroup_per_zone * mem_cgroup_zoneinfo(struct mem_cgroup *mem, int nid, int zid) { @@ -1818,24 +1835,6 @@ static void mem_cgroup_cancel_charge(str __mem_cgroup_cancel_charge(mem, 1); } -/* - * A helper function to get mem_cgroup from ID. must be called under - * rcu_read_lock(). The caller must check css_is_removed() or some if - * it's concern. (dropping refcnt from swap can be called against removed - * memcg.) - */ -static struct mem_cgroup *mem_cgroup_lookup(unsigned short id) -{ - struct cgroup_subsys_state *css; - - /* ID 0 is unused ID */ - if (!id) - return NULL; - css = css_lookup(&mem_cgroup_subsys, id); - if (!css) - return NULL; - return container_of(css, struct mem_cgroup, css); -} struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) { @@ -1856,7 +1855,7 @@ struct mem_cgroup *try_get_mem_cgroup_fr ent.val = page_private(page); id = lookup_swap_cgroup(ent); rcu_read_lock(); - mem = mem_cgroup_lookup(id); + mem = id_to_mem(id); if (mem && !css_tryget(&mem->css)) mem = NULL; rcu_read_unlock(); @@ -2208,7 +2207,7 @@ __mem_cgroup_commit_charge_swapin(struct id = swap_cgroup_record(ent, 0); rcu_read_lock(); - memcg = mem_cgroup_lookup(id); + memcg = id_to_mem(id); if (memcg) { /* * This recorded memcg can be obsolete one. So, avoid @@ -2472,7 +2471,7 @@ void mem_cgroup_uncharge_swap(swp_entry_ id = swap_cgroup_record(ent, 0); rcu_read_lock(); - memcg = mem_cgroup_lookup(id); + memcg = id_to_mem(id); if (memcg) { /* * We uncharge this because swap is freed. @@ -3983,32 +3982,42 @@ static void free_mem_cgroup_per_zone_inf kfree(mem->info.nodeinfo[node]); } -static struct mem_cgroup *mem_cgroup_alloc(void) +struct virt_array memcg_varray; + +static int mem_cgroup_custom_id(struct cgroup_subsys *ss, struct cgroup *cont) { - struct mem_cgroup *mem; - int size = sizeof(struct mem_cgroup); + struct mem_cgroup *mem = mem_cgroup_from_cont(cont); + return mem->custom_id; +} - /* Can be very big if MAX_NUMNODES is very big */ - if (size < PAGE_SIZE) - mem = kmalloc(size, GFP_KERNEL); - else - mem = vmalloc(size); +static struct mem_cgroup *mem_cgroup_alloc(struct cgroup *cgroup) +{ + struct mem_cgroup *mem; + int idx; - if (!mem) + if (cgroup->parent == NULL) { + mem_cgroup_base = create_varray(&memcg_varray, sizeof(*mem), + CONFIG_MEM_CGROUP_MAX_GROUPS); + BUG_ON(IS_ERR_OR_NULL(mem_cgroup_base)); + } + /* 0 is unused ID.(see css_id's spec). */ + idx = varray_find_free_index(&memcg_varray, 1); + if (idx == memcg_varray.nelem) return NULL; - - memset(mem, 0, size); + mem = alloc_varray_item(&memcg_varray, idx); + if (IS_ERR_OR_NULL(mem)) + return NULL; + memset(mem, 0, sizeof(*mem)); mem->stat = alloc_percpu(struct mem_cgroup_stat_cpu); if (!mem->stat) { - if (size < PAGE_SIZE) - kfree(mem); - else - vfree(mem); + free_varray_item(&memcg_varray, idx); mem = NULL; - } + } else + mem->custom_id = idx; return mem; } + /* * At destroying mem_cgroup, references from swap_cgroup can remain. * (scanning all at force_empty is too costly...) @@ -4031,10 +4040,7 @@ static void __mem_cgroup_free(struct mem free_mem_cgroup_per_zone_info(mem, node); free_percpu(mem->stat); - if (sizeof(struct mem_cgroup) < PAGE_SIZE) - kfree(mem); - else - vfree(mem); + free_varray_item(&memcg_varray, mem->custom_id); } static void mem_cgroup_get(struct mem_cgroup *mem) @@ -4111,7 +4117,7 @@ mem_cgroup_create(struct cgroup_subsys * long error = -ENOMEM; int node; - mem = mem_cgroup_alloc(); + mem = mem_cgroup_alloc(cont); if (!mem) return ERR_PTR(error); @@ -4692,6 +4698,7 @@ struct cgroup_subsys mem_cgroup_subsys = .can_attach = mem_cgroup_can_attach, .cancel_attach = mem_cgroup_cancel_attach, .attach = mem_cgroup_move_task, + .custom_id = mem_cgroup_custom_id, .early_init = 0, .use_id = 1, }; -- 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/