Balbir Singh | 8cdea7c | 2008-02-07 00:13:50 -0800 | [diff] [blame^] | 1 | /* memcontrol.c - Memory Controller |
| 2 | * |
| 3 | * Copyright IBM Corporation, 2007 |
| 4 | * Author Balbir Singh <balbir@linux.vnet.ibm.com> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | */ |
| 16 | |
| 17 | #include <linux/res_counter.h> |
| 18 | #include <linux/memcontrol.h> |
| 19 | #include <linux/cgroup.h> |
| 20 | |
| 21 | struct cgroup_subsys mem_cgroup_subsys; |
| 22 | |
| 23 | /* |
| 24 | * The memory controller data structure. The memory controller controls both |
| 25 | * page cache and RSS per cgroup. We would eventually like to provide |
| 26 | * statistics based on the statistics developed by Rik Van Riel for clock-pro, |
| 27 | * to help the administrator determine what knobs to tune. |
| 28 | * |
| 29 | * TODO: Add a water mark for the memory controller. Reclaim will begin when |
| 30 | * we hit the water mark. |
| 31 | */ |
| 32 | struct mem_cgroup { |
| 33 | struct cgroup_subsys_state css; |
| 34 | /* |
| 35 | * the counter to account for memory usage |
| 36 | */ |
| 37 | struct res_counter res; |
| 38 | }; |
| 39 | |
| 40 | /* |
| 41 | * A page_cgroup page is associated with every page descriptor. The |
| 42 | * page_cgroup helps us identify information about the cgroup |
| 43 | */ |
| 44 | struct page_cgroup { |
| 45 | struct list_head lru; /* per cgroup LRU list */ |
| 46 | struct page *page; |
| 47 | struct mem_cgroup *mem_cgroup; |
| 48 | }; |
| 49 | |
| 50 | |
| 51 | static inline |
| 52 | struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) |
| 53 | { |
| 54 | return container_of(cgroup_subsys_state(cont, |
| 55 | mem_cgroup_subsys_id), struct mem_cgroup, |
| 56 | css); |
| 57 | } |
| 58 | |
| 59 | static ssize_t mem_cgroup_read(struct cgroup *cont, struct cftype *cft, |
| 60 | struct file *file, char __user *userbuf, size_t nbytes, |
| 61 | loff_t *ppos) |
| 62 | { |
| 63 | return res_counter_read(&mem_cgroup_from_cont(cont)->res, |
| 64 | cft->private, userbuf, nbytes, ppos); |
| 65 | } |
| 66 | |
| 67 | static ssize_t mem_cgroup_write(struct cgroup *cont, struct cftype *cft, |
| 68 | struct file *file, const char __user *userbuf, |
| 69 | size_t nbytes, loff_t *ppos) |
| 70 | { |
| 71 | return res_counter_write(&mem_cgroup_from_cont(cont)->res, |
| 72 | cft->private, userbuf, nbytes, ppos); |
| 73 | } |
| 74 | |
| 75 | static struct cftype mem_cgroup_files[] = { |
| 76 | { |
| 77 | .name = "usage", |
| 78 | .private = RES_USAGE, |
| 79 | .read = mem_cgroup_read, |
| 80 | }, |
| 81 | { |
| 82 | .name = "limit", |
| 83 | .private = RES_LIMIT, |
| 84 | .write = mem_cgroup_write, |
| 85 | .read = mem_cgroup_read, |
| 86 | }, |
| 87 | { |
| 88 | .name = "failcnt", |
| 89 | .private = RES_FAILCNT, |
| 90 | .read = mem_cgroup_read, |
| 91 | }, |
| 92 | }; |
| 93 | |
| 94 | static struct cgroup_subsys_state * |
| 95 | mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) |
| 96 | { |
| 97 | struct mem_cgroup *mem; |
| 98 | |
| 99 | mem = kzalloc(sizeof(struct mem_cgroup), GFP_KERNEL); |
| 100 | if (!mem) |
| 101 | return -ENOMEM; |
| 102 | |
| 103 | res_counter_init(&mem->res); |
| 104 | return &mem->css; |
| 105 | } |
| 106 | |
| 107 | static void mem_cgroup_destroy(struct cgroup_subsys *ss, |
| 108 | struct cgroup *cont) |
| 109 | { |
| 110 | kfree(mem_cgroup_from_cont(cont)); |
| 111 | } |
| 112 | |
| 113 | static int mem_cgroup_populate(struct cgroup_subsys *ss, |
| 114 | struct cgroup *cont) |
| 115 | { |
| 116 | return cgroup_add_files(cont, ss, mem_cgroup_files, |
| 117 | ARRAY_SIZE(mem_cgroup_files)); |
| 118 | } |
| 119 | |
| 120 | struct cgroup_subsys mem_cgroup_subsys = { |
| 121 | .name = "memory", |
| 122 | .subsys_id = mem_cgroup_subsys_id, |
| 123 | .create = mem_cgroup_create, |
| 124 | .destroy = mem_cgroup_destroy, |
| 125 | .populate = mem_cgroup_populate, |
| 126 | .early_init = 0, |
| 127 | }; |