Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * kernel/cpuset.c |
| 3 | * |
| 4 | * Processor and Memory placement constraints for sets of tasks. |
| 5 | * |
| 6 | * Copyright (C) 2003 BULL SA. |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 7 | * Copyright (C) 2004-2007 Silicon Graphics, Inc. |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 8 | * Copyright (C) 2006 Google, Inc |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | * |
| 10 | * Portions derived from Patrick Mochel's sysfs code. |
| 11 | * sysfs is Copyright (c) 2001-3 Patrick Mochel |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | * |
Paul Jackson | 825a46a | 2006-03-24 03:16:03 -0800 | [diff] [blame] | 13 | * 2003-10-10 Written by Simon Derr. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | * 2003-10-22 Updates by Stephen Hemminger. |
Paul Jackson | 825a46a | 2006-03-24 03:16:03 -0800 | [diff] [blame] | 15 | * 2004 May-July Rework by Paul Jackson. |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 16 | * 2006 Rework by Paul Menage to use generic cgroups |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 17 | * 2008 Rework of the scheduler domains and CPU hotplug handling |
| 18 | * by Max Krasnyansky |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | * |
| 20 | * This file is subject to the terms and conditions of the GNU General Public |
| 21 | * License. See the file COPYING in the main directory of the Linux |
| 22 | * distribution for more details. |
| 23 | */ |
| 24 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | #include <linux/cpu.h> |
| 26 | #include <linux/cpumask.h> |
| 27 | #include <linux/cpuset.h> |
| 28 | #include <linux/err.h> |
| 29 | #include <linux/errno.h> |
| 30 | #include <linux/file.h> |
| 31 | #include <linux/fs.h> |
| 32 | #include <linux/init.h> |
| 33 | #include <linux/interrupt.h> |
| 34 | #include <linux/kernel.h> |
| 35 | #include <linux/kmod.h> |
| 36 | #include <linux/list.h> |
Paul Jackson | 68860ec | 2005-10-30 15:02:36 -0800 | [diff] [blame] | 37 | #include <linux/mempolicy.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | #include <linux/mm.h> |
Miao Xie | f481891 | 2008-11-19 15:36:30 -0800 | [diff] [blame] | 39 | #include <linux/memory.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | #include <linux/module.h> |
| 41 | #include <linux/mount.h> |
| 42 | #include <linux/namei.h> |
| 43 | #include <linux/pagemap.h> |
| 44 | #include <linux/proc_fs.h> |
Paul Jackson | 6b9c260 | 2006-01-08 01:02:02 -0800 | [diff] [blame] | 45 | #include <linux/rcupdate.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | #include <linux/sched.h> |
| 47 | #include <linux/seq_file.h> |
David Quigley | 22fb52d | 2006-06-23 02:04:00 -0700 | [diff] [blame] | 48 | #include <linux/security.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | #include <linux/slab.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | #include <linux/spinlock.h> |
| 51 | #include <linux/stat.h> |
| 52 | #include <linux/string.h> |
| 53 | #include <linux/time.h> |
| 54 | #include <linux/backing-dev.h> |
| 55 | #include <linux/sort.h> |
| 56 | |
| 57 | #include <asm/uaccess.h> |
| 58 | #include <asm/atomic.h> |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 59 | #include <linux/mutex.h> |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 60 | #include <linux/workqueue.h> |
| 61 | #include <linux/cgroup.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | |
Paul Jackson | 202f72d | 2006-01-08 01:01:57 -0800 | [diff] [blame] | 63 | /* |
Miao Xie | f90d411 | 2009-01-16 10:24:10 +0800 | [diff] [blame] | 64 | * Workqueue for cpuset related tasks. |
| 65 | * |
| 66 | * Using kevent workqueue may cause deadlock when memory_migrate |
| 67 | * is set. So we create a separate workqueue thread for cpuset. |
| 68 | */ |
| 69 | static struct workqueue_struct *cpuset_wq; |
| 70 | |
| 71 | /* |
Paul Jackson | 202f72d | 2006-01-08 01:01:57 -0800 | [diff] [blame] | 72 | * Tracks how many cpusets are currently defined in system. |
| 73 | * When there is only one cpuset (the root cpuset) we can |
| 74 | * short circuit some hooks. |
| 75 | */ |
Paul Jackson | 7edc596 | 2006-01-08 01:02:03 -0800 | [diff] [blame] | 76 | int number_of_cpusets __read_mostly; |
Paul Jackson | 202f72d | 2006-01-08 01:01:57 -0800 | [diff] [blame] | 77 | |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 78 | /* Forward declare cgroup structures */ |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 79 | struct cgroup_subsys cpuset_subsys; |
| 80 | struct cpuset; |
| 81 | |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 82 | /* See "Frequency meter" comments, below. */ |
| 83 | |
| 84 | struct fmeter { |
| 85 | int cnt; /* unprocessed events count */ |
| 86 | int val; /* most recent output value */ |
| 87 | time_t time; /* clock (secs) when val computed */ |
| 88 | spinlock_t lock; /* guards read or write of above */ |
| 89 | }; |
| 90 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | struct cpuset { |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 92 | struct cgroup_subsys_state css; |
| 93 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | unsigned long flags; /* "unsigned long" so bitops work */ |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 95 | cpumask_var_t cpus_allowed; /* CPUs allowed to tasks in cpuset */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | nodemask_t mems_allowed; /* Memory Nodes allowed to tasks */ |
| 97 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 98 | struct cpuset *parent; /* my parent */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 99 | |
| 100 | /* |
| 101 | * Copy of global cpuset_mems_generation as of the most |
| 102 | * recent time this cpuset changed its mems_allowed. |
| 103 | */ |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 104 | int mems_generation; |
| 105 | |
| 106 | struct fmeter fmeter; /* memory_pressure filter */ |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 107 | |
| 108 | /* partition number for rebuild_sched_domains() */ |
| 109 | int pn; |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 110 | |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 111 | /* for custom sched domain */ |
| 112 | int relax_domain_level; |
| 113 | |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 114 | /* used for walking a cpuset heirarchy */ |
| 115 | struct list_head stack_list; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | }; |
| 117 | |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 118 | /* Retrieve the cpuset for a cgroup */ |
| 119 | static inline struct cpuset *cgroup_cs(struct cgroup *cont) |
| 120 | { |
| 121 | return container_of(cgroup_subsys_state(cont, cpuset_subsys_id), |
| 122 | struct cpuset, css); |
| 123 | } |
| 124 | |
| 125 | /* Retrieve the cpuset for a task */ |
| 126 | static inline struct cpuset *task_cs(struct task_struct *task) |
| 127 | { |
| 128 | return container_of(task_subsys_state(task, cpuset_subsys_id), |
| 129 | struct cpuset, css); |
| 130 | } |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 131 | struct cpuset_hotplug_scanner { |
| 132 | struct cgroup_scanner scan; |
| 133 | struct cgroup *to; |
| 134 | }; |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 135 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | /* bits in struct cpuset flags field */ |
| 137 | typedef enum { |
| 138 | CS_CPU_EXCLUSIVE, |
| 139 | CS_MEM_EXCLUSIVE, |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 140 | CS_MEM_HARDWALL, |
Paul Jackson | 45b07ef | 2006-01-08 01:00:56 -0800 | [diff] [blame] | 141 | CS_MEMORY_MIGRATE, |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 142 | CS_SCHED_LOAD_BALANCE, |
Paul Jackson | 825a46a | 2006-03-24 03:16:03 -0800 | [diff] [blame] | 143 | CS_SPREAD_PAGE, |
| 144 | CS_SPREAD_SLAB, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 145 | } cpuset_flagbits_t; |
| 146 | |
| 147 | /* convenient tests for these bits */ |
| 148 | static inline int is_cpu_exclusive(const struct cpuset *cs) |
| 149 | { |
Paul Jackson | 7b5b9ef | 2006-03-24 03:16:00 -0800 | [diff] [blame] | 150 | return test_bit(CS_CPU_EXCLUSIVE, &cs->flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 151 | } |
| 152 | |
| 153 | static inline int is_mem_exclusive(const struct cpuset *cs) |
| 154 | { |
Paul Jackson | 7b5b9ef | 2006-03-24 03:16:00 -0800 | [diff] [blame] | 155 | return test_bit(CS_MEM_EXCLUSIVE, &cs->flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 156 | } |
| 157 | |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 158 | static inline int is_mem_hardwall(const struct cpuset *cs) |
| 159 | { |
| 160 | return test_bit(CS_MEM_HARDWALL, &cs->flags); |
| 161 | } |
| 162 | |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 163 | static inline int is_sched_load_balance(const struct cpuset *cs) |
| 164 | { |
| 165 | return test_bit(CS_SCHED_LOAD_BALANCE, &cs->flags); |
| 166 | } |
| 167 | |
Paul Jackson | 45b07ef | 2006-01-08 01:00:56 -0800 | [diff] [blame] | 168 | static inline int is_memory_migrate(const struct cpuset *cs) |
| 169 | { |
Paul Jackson | 7b5b9ef | 2006-03-24 03:16:00 -0800 | [diff] [blame] | 170 | return test_bit(CS_MEMORY_MIGRATE, &cs->flags); |
Paul Jackson | 45b07ef | 2006-01-08 01:00:56 -0800 | [diff] [blame] | 171 | } |
| 172 | |
Paul Jackson | 825a46a | 2006-03-24 03:16:03 -0800 | [diff] [blame] | 173 | static inline int is_spread_page(const struct cpuset *cs) |
| 174 | { |
| 175 | return test_bit(CS_SPREAD_PAGE, &cs->flags); |
| 176 | } |
| 177 | |
| 178 | static inline int is_spread_slab(const struct cpuset *cs) |
| 179 | { |
| 180 | return test_bit(CS_SPREAD_SLAB, &cs->flags); |
| 181 | } |
| 182 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | /* |
Paul Jackson | 151a442 | 2006-03-24 03:16:11 -0800 | [diff] [blame] | 184 | * Increment this integer everytime any cpuset changes its |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | * mems_allowed value. Users of cpusets can track this generation |
| 186 | * number, and avoid having to lock and reload mems_allowed unless |
| 187 | * the cpuset they're using changes generation. |
| 188 | * |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 189 | * A single, global generation is needed because cpuset_attach_task() could |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 190 | * reattach a task to a different cpuset, which must not have its |
| 191 | * generation numbers aliased with those of that tasks previous cpuset. |
| 192 | * |
| 193 | * Generations are needed for mems_allowed because one task cannot |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 194 | * modify another's memory placement. So we must enable every task, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 195 | * on every visit to __alloc_pages(), to efficiently check whether |
| 196 | * its current->cpuset->mems_allowed has changed, requiring an update |
| 197 | * of its current->mems_allowed. |
Paul Jackson | 151a442 | 2006-03-24 03:16:11 -0800 | [diff] [blame] | 198 | * |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 199 | * Since writes to cpuset_mems_generation are guarded by the cgroup lock |
Paul Jackson | 151a442 | 2006-03-24 03:16:11 -0800 | [diff] [blame] | 200 | * there is no need to mark it atomic. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 201 | */ |
Paul Jackson | 151a442 | 2006-03-24 03:16:11 -0800 | [diff] [blame] | 202 | static int cpuset_mems_generation; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | |
| 204 | static struct cpuset top_cpuset = { |
| 205 | .flags = ((1 << CS_CPU_EXCLUSIVE) | (1 << CS_MEM_EXCLUSIVE)), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | }; |
| 207 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 208 | /* |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 209 | * There are two global mutexes guarding cpuset structures. The first |
| 210 | * is the main control groups cgroup_mutex, accessed via |
| 211 | * cgroup_lock()/cgroup_unlock(). The second is the cpuset-specific |
| 212 | * callback_mutex, below. They can nest. It is ok to first take |
| 213 | * cgroup_mutex, then nest callback_mutex. We also require taking |
| 214 | * task_lock() when dereferencing a task's cpuset pointer. See "The |
| 215 | * task_lock() exception", at the end of this comment. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 216 | * |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 217 | * A task must hold both mutexes to modify cpusets. If a task |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 218 | * holds cgroup_mutex, then it blocks others wanting that mutex, |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 219 | * ensuring that it is the only task able to also acquire callback_mutex |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 220 | * and be able to modify cpusets. It can perform various checks on |
| 221 | * the cpuset structure first, knowing nothing will change. It can |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 222 | * also allocate memory while just holding cgroup_mutex. While it is |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 223 | * performing these checks, various callback routines can briefly |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 224 | * acquire callback_mutex to query cpusets. Once it is ready to make |
| 225 | * the changes, it takes callback_mutex, blocking everyone else. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | * |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 227 | * Calls to the kernel memory allocator can not be made while holding |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 228 | * callback_mutex, as that would risk double tripping on callback_mutex |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 229 | * from one of the callbacks into the cpuset code from within |
| 230 | * __alloc_pages(). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | * |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 232 | * If a task is only holding callback_mutex, then it has read-only |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 233 | * access to cpusets. |
| 234 | * |
| 235 | * The task_struct fields mems_allowed and mems_generation may only |
| 236 | * be accessed in the context of that task, so require no locks. |
| 237 | * |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 238 | * The cpuset_common_file_read() handlers only hold callback_mutex across |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 239 | * small pieces of code, such as when reading out possibly multi-word |
| 240 | * cpumasks and nodemasks. |
| 241 | * |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 242 | * Accessing a task's cpuset should be done in accordance with the |
| 243 | * guidelines for accessing subsystem state in kernel/cgroup.c |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | */ |
| 245 | |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 246 | static DEFINE_MUTEX(callback_mutex); |
Paul Jackson | 4247bdc | 2005-09-10 00:26:06 -0700 | [diff] [blame] | 247 | |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 248 | /* |
David Rientjes | 75aa199 | 2009-01-06 14:39:01 -0800 | [diff] [blame] | 249 | * cpuset_buffer_lock protects both the cpuset_name and cpuset_nodelist |
| 250 | * buffers. They are statically allocated to prevent using excess stack |
| 251 | * when calling cpuset_print_task_mems_allowed(). |
| 252 | */ |
| 253 | #define CPUSET_NAME_LEN (128) |
| 254 | #define CPUSET_NODELIST_LEN (256) |
| 255 | static char cpuset_name[CPUSET_NAME_LEN]; |
| 256 | static char cpuset_nodelist[CPUSET_NODELIST_LEN]; |
| 257 | static DEFINE_SPINLOCK(cpuset_buffer_lock); |
| 258 | |
| 259 | /* |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 260 | * This is ugly, but preserves the userspace API for existing cpuset |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 261 | * users. If someone tries to mount the "cpuset" filesystem, we |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 262 | * silently switch it to mount "cgroup" instead |
| 263 | */ |
David Howells | 454e239 | 2006-06-23 02:02:57 -0700 | [diff] [blame] | 264 | static int cpuset_get_sb(struct file_system_type *fs_type, |
| 265 | int flags, const char *unused_dev_name, |
| 266 | void *data, struct vfsmount *mnt) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 267 | { |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 268 | struct file_system_type *cgroup_fs = get_fs_type("cgroup"); |
| 269 | int ret = -ENODEV; |
| 270 | if (cgroup_fs) { |
| 271 | char mountopts[] = |
| 272 | "cpuset,noprefix," |
| 273 | "release_agent=/sbin/cpuset_release_agent"; |
| 274 | ret = cgroup_fs->get_sb(cgroup_fs, flags, |
| 275 | unused_dev_name, mountopts, mnt); |
| 276 | put_filesystem(cgroup_fs); |
| 277 | } |
| 278 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 279 | } |
| 280 | |
| 281 | static struct file_system_type cpuset_fs_type = { |
| 282 | .name = "cpuset", |
| 283 | .get_sb = cpuset_get_sb, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 284 | }; |
| 285 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 286 | /* |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 287 | * Return in pmask the portion of a cpusets's cpus_allowed that |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | * are online. If none are online, walk up the cpuset hierarchy |
| 289 | * until we find one that does have some online cpus. If we get |
| 290 | * all the way to the top and still haven't found any online cpus, |
| 291 | * return cpu_online_map. Or if passed a NULL cs from an exit'ing |
| 292 | * task, return cpu_online_map. |
| 293 | * |
| 294 | * One way or another, we guarantee to return some non-empty subset |
| 295 | * of cpu_online_map. |
| 296 | * |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 297 | * Call with callback_mutex held. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | */ |
| 299 | |
Li Zefan | 6af866a | 2009-01-07 18:08:45 -0800 | [diff] [blame] | 300 | static void guarantee_online_cpus(const struct cpuset *cs, |
| 301 | struct cpumask *pmask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | { |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 303 | while (cs && !cpumask_intersects(cs->cpus_allowed, cpu_online_mask)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 304 | cs = cs->parent; |
| 305 | if (cs) |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 306 | cpumask_and(pmask, cs->cpus_allowed, cpu_online_mask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | else |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 308 | cpumask_copy(pmask, cpu_online_mask); |
| 309 | BUG_ON(!cpumask_intersects(pmask, cpu_online_mask)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 310 | } |
| 311 | |
| 312 | /* |
| 313 | * Return in *pmask the portion of a cpusets's mems_allowed that |
Christoph Lameter | 0e1e7c7 | 2007-10-16 01:25:38 -0700 | [diff] [blame] | 314 | * are online, with memory. If none are online with memory, walk |
| 315 | * up the cpuset hierarchy until we find one that does have some |
| 316 | * online mems. If we get all the way to the top and still haven't |
| 317 | * found any online mems, return node_states[N_HIGH_MEMORY]. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 318 | * |
| 319 | * One way or another, we guarantee to return some non-empty subset |
Christoph Lameter | 0e1e7c7 | 2007-10-16 01:25:38 -0700 | [diff] [blame] | 320 | * of node_states[N_HIGH_MEMORY]. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | * |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 322 | * Call with callback_mutex held. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 323 | */ |
| 324 | |
| 325 | static void guarantee_online_mems(const struct cpuset *cs, nodemask_t *pmask) |
| 326 | { |
Christoph Lameter | 0e1e7c7 | 2007-10-16 01:25:38 -0700 | [diff] [blame] | 327 | while (cs && !nodes_intersects(cs->mems_allowed, |
| 328 | node_states[N_HIGH_MEMORY])) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 329 | cs = cs->parent; |
| 330 | if (cs) |
Christoph Lameter | 0e1e7c7 | 2007-10-16 01:25:38 -0700 | [diff] [blame] | 331 | nodes_and(*pmask, cs->mems_allowed, |
| 332 | node_states[N_HIGH_MEMORY]); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 333 | else |
Christoph Lameter | 0e1e7c7 | 2007-10-16 01:25:38 -0700 | [diff] [blame] | 334 | *pmask = node_states[N_HIGH_MEMORY]; |
| 335 | BUG_ON(!nodes_intersects(*pmask, node_states[N_HIGH_MEMORY])); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 336 | } |
| 337 | |
Paul Jackson | cf2a473c | 2006-01-08 01:01:54 -0800 | [diff] [blame] | 338 | /** |
| 339 | * cpuset_update_task_memory_state - update task memory placement |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | * |
Paul Jackson | cf2a473c | 2006-01-08 01:01:54 -0800 | [diff] [blame] | 341 | * If the current tasks cpusets mems_allowed changed behind our |
| 342 | * backs, update current->mems_allowed, mems_generation and task NUMA |
| 343 | * mempolicy to the new value. |
| 344 | * |
| 345 | * Task mempolicy is updated by rebinding it relative to the |
| 346 | * current->cpuset if a task has its memory placement changed. |
| 347 | * Do not call this routine if in_interrupt(). |
| 348 | * |
Paul Jackson | 4a01c8d | 2006-03-31 02:30:50 -0800 | [diff] [blame] | 349 | * Call without callback_mutex or task_lock() held. May be |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 350 | * called with or without cgroup_mutex held. Thanks in part to |
| 351 | * 'the_top_cpuset_hack', the task's cpuset pointer will never |
David Rientjes | 41f7f60 | 2008-03-04 23:32:38 -0800 | [diff] [blame] | 352 | * be NULL. This routine also might acquire callback_mutex during |
| 353 | * call. |
Paul Jackson | 5aa15b5 | 2005-10-30 15:02:28 -0800 | [diff] [blame] | 354 | * |
Paul Jackson | 6b9c260 | 2006-01-08 01:02:02 -0800 | [diff] [blame] | 355 | * Reading current->cpuset->mems_generation doesn't need task_lock |
| 356 | * to guard the current->cpuset derefence, because it is guarded |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 357 | * from concurrent freeing of current->cpuset using RCU. |
Paul Jackson | 6b9c260 | 2006-01-08 01:02:02 -0800 | [diff] [blame] | 358 | * |
| 359 | * The rcu_dereference() is technically probably not needed, |
| 360 | * as I don't actually mind if I see a new cpuset pointer but |
| 361 | * an old value of mems_generation. However this really only |
| 362 | * matters on alpha systems using cpusets heavily. If I dropped |
| 363 | * that rcu_dereference(), it would save them a memory barrier. |
| 364 | * For all other arch's, rcu_dereference is a no-op anyway, and for |
| 365 | * alpha systems not using cpusets, another planned optimization, |
| 366 | * avoiding the rcu critical section for tasks in the root cpuset |
| 367 | * which is statically allocated, so can't vanish, will make this |
| 368 | * irrelevant. Better to use RCU as intended, than to engage in |
| 369 | * some cute trick to save a memory barrier that is impossible to |
| 370 | * test, for alpha systems using cpusets heavily, which might not |
| 371 | * even exist. |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 372 | * |
| 373 | * This routine is needed to update the per-task mems_allowed data, |
| 374 | * within the tasks context, when it is trying to allocate memory |
| 375 | * (in various mm/mempolicy.c routines) and notices that some other |
| 376 | * task has been modifying its cpuset. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 377 | */ |
| 378 | |
Randy Dunlap | fe85a99 | 2006-02-03 03:04:23 -0800 | [diff] [blame] | 379 | void cpuset_update_task_memory_state(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 380 | { |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 381 | int my_cpusets_mem_gen; |
Paul Jackson | cf2a473c | 2006-01-08 01:01:54 -0800 | [diff] [blame] | 382 | struct task_struct *tsk = current; |
Paul Jackson | 6b9c260 | 2006-01-08 01:02:02 -0800 | [diff] [blame] | 383 | struct cpuset *cs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 384 | |
Lai Jiangshan | 1333771 | 2009-01-07 18:08:39 -0800 | [diff] [blame] | 385 | rcu_read_lock(); |
| 386 | my_cpusets_mem_gen = task_cs(tsk)->mems_generation; |
| 387 | rcu_read_unlock(); |
Paul Jackson | cf2a473c | 2006-01-08 01:01:54 -0800 | [diff] [blame] | 388 | |
| 389 | if (my_cpusets_mem_gen != tsk->cpuset_mems_generation) { |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 390 | mutex_lock(&callback_mutex); |
Paul Jackson | cf2a473c | 2006-01-08 01:01:54 -0800 | [diff] [blame] | 391 | task_lock(tsk); |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 392 | cs = task_cs(tsk); /* Maybe changed when task not locked */ |
Paul Jackson | cf2a473c | 2006-01-08 01:01:54 -0800 | [diff] [blame] | 393 | guarantee_online_mems(cs, &tsk->mems_allowed); |
| 394 | tsk->cpuset_mems_generation = cs->mems_generation; |
Paul Jackson | 825a46a | 2006-03-24 03:16:03 -0800 | [diff] [blame] | 395 | if (is_spread_page(cs)) |
| 396 | tsk->flags |= PF_SPREAD_PAGE; |
| 397 | else |
| 398 | tsk->flags &= ~PF_SPREAD_PAGE; |
| 399 | if (is_spread_slab(cs)) |
| 400 | tsk->flags |= PF_SPREAD_SLAB; |
| 401 | else |
| 402 | tsk->flags &= ~PF_SPREAD_SLAB; |
Paul Jackson | cf2a473c | 2006-01-08 01:01:54 -0800 | [diff] [blame] | 403 | task_unlock(tsk); |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 404 | mutex_unlock(&callback_mutex); |
Paul Jackson | 74cb215 | 2006-01-08 01:01:56 -0800 | [diff] [blame] | 405 | mpol_rebind_task(tsk, &tsk->mems_allowed); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | } |
| 407 | } |
| 408 | |
| 409 | /* |
| 410 | * is_cpuset_subset(p, q) - Is cpuset p a subset of cpuset q? |
| 411 | * |
| 412 | * One cpuset is a subset of another if all its allowed CPUs and |
| 413 | * Memory Nodes are a subset of the other, and its exclusive flags |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 414 | * are only set if the other's are set. Call holding cgroup_mutex. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 415 | */ |
| 416 | |
| 417 | static int is_cpuset_subset(const struct cpuset *p, const struct cpuset *q) |
| 418 | { |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 419 | return cpumask_subset(p->cpus_allowed, q->cpus_allowed) && |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 420 | nodes_subset(p->mems_allowed, q->mems_allowed) && |
| 421 | is_cpu_exclusive(p) <= is_cpu_exclusive(q) && |
| 422 | is_mem_exclusive(p) <= is_mem_exclusive(q); |
| 423 | } |
| 424 | |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 425 | /** |
| 426 | * alloc_trial_cpuset - allocate a trial cpuset |
| 427 | * @cs: the cpuset that the trial cpuset duplicates |
| 428 | */ |
| 429 | static struct cpuset *alloc_trial_cpuset(const struct cpuset *cs) |
| 430 | { |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 431 | struct cpuset *trial; |
| 432 | |
| 433 | trial = kmemdup(cs, sizeof(*cs), GFP_KERNEL); |
| 434 | if (!trial) |
| 435 | return NULL; |
| 436 | |
| 437 | if (!alloc_cpumask_var(&trial->cpus_allowed, GFP_KERNEL)) { |
| 438 | kfree(trial); |
| 439 | return NULL; |
| 440 | } |
| 441 | cpumask_copy(trial->cpus_allowed, cs->cpus_allowed); |
| 442 | |
| 443 | return trial; |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 444 | } |
| 445 | |
| 446 | /** |
| 447 | * free_trial_cpuset - free the trial cpuset |
| 448 | * @trial: the trial cpuset to be freed |
| 449 | */ |
| 450 | static void free_trial_cpuset(struct cpuset *trial) |
| 451 | { |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 452 | free_cpumask_var(trial->cpus_allowed); |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 453 | kfree(trial); |
| 454 | } |
| 455 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 456 | /* |
| 457 | * validate_change() - Used to validate that any proposed cpuset change |
| 458 | * follows the structural rules for cpusets. |
| 459 | * |
| 460 | * If we replaced the flag and mask values of the current cpuset |
| 461 | * (cur) with those values in the trial cpuset (trial), would |
| 462 | * our various subset and exclusive rules still be valid? Presumes |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 463 | * cgroup_mutex held. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | * |
| 465 | * 'cur' is the address of an actual, in-use cpuset. Operations |
| 466 | * such as list traversal that depend on the actual address of the |
| 467 | * cpuset in the list must use cur below, not trial. |
| 468 | * |
| 469 | * 'trial' is the address of bulk structure copy of cur, with |
| 470 | * perhaps one or more of the fields cpus_allowed, mems_allowed, |
| 471 | * or flags changed to new, trial values. |
| 472 | * |
| 473 | * Return 0 if valid, -errno if not. |
| 474 | */ |
| 475 | |
| 476 | static int validate_change(const struct cpuset *cur, const struct cpuset *trial) |
| 477 | { |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 478 | struct cgroup *cont; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 479 | struct cpuset *c, *par; |
| 480 | |
| 481 | /* Each of our child cpusets must be a subset of us */ |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 482 | list_for_each_entry(cont, &cur->css.cgroup->children, sibling) { |
| 483 | if (!is_cpuset_subset(cgroup_cs(cont), trial)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 484 | return -EBUSY; |
| 485 | } |
| 486 | |
| 487 | /* Remaining checks don't apply to root cpuset */ |
Paul Jackson | 6960406 | 2006-12-06 20:36:15 -0800 | [diff] [blame] | 488 | if (cur == &top_cpuset) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 489 | return 0; |
| 490 | |
Paul Jackson | 6960406 | 2006-12-06 20:36:15 -0800 | [diff] [blame] | 491 | par = cur->parent; |
| 492 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 493 | /* We must be a subset of our parent cpuset */ |
| 494 | if (!is_cpuset_subset(trial, par)) |
| 495 | return -EACCES; |
| 496 | |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 497 | /* |
| 498 | * If either I or some sibling (!= me) is exclusive, we can't |
| 499 | * overlap |
| 500 | */ |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 501 | list_for_each_entry(cont, &par->css.cgroup->children, sibling) { |
| 502 | c = cgroup_cs(cont); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 503 | if ((is_cpu_exclusive(trial) || is_cpu_exclusive(c)) && |
| 504 | c != cur && |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 505 | cpumask_intersects(trial->cpus_allowed, c->cpus_allowed)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | return -EINVAL; |
| 507 | if ((is_mem_exclusive(trial) || is_mem_exclusive(c)) && |
| 508 | c != cur && |
| 509 | nodes_intersects(trial->mems_allowed, c->mems_allowed)) |
| 510 | return -EINVAL; |
| 511 | } |
| 512 | |
Paul Jackson | 020958b | 2007-10-18 23:40:21 -0700 | [diff] [blame] | 513 | /* Cpusets with tasks can't have empty cpus_allowed or mems_allowed */ |
| 514 | if (cgroup_task_count(cur->css.cgroup)) { |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 515 | if (cpumask_empty(trial->cpus_allowed) || |
Paul Jackson | 020958b | 2007-10-18 23:40:21 -0700 | [diff] [blame] | 516 | nodes_empty(trial->mems_allowed)) { |
| 517 | return -ENOSPC; |
| 518 | } |
| 519 | } |
| 520 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 521 | return 0; |
| 522 | } |
| 523 | |
Dinakar Guniguntala | 85d7b94 | 2005-06-25 14:57:34 -0700 | [diff] [blame] | 524 | /* |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 525 | * Helper routine for generate_sched_domains(). |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 526 | * Do cpusets a, b have overlapping cpus_allowed masks? |
| 527 | */ |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 528 | static int cpusets_overlap(struct cpuset *a, struct cpuset *b) |
| 529 | { |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 530 | return cpumask_intersects(a->cpus_allowed, b->cpus_allowed); |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 531 | } |
| 532 | |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 533 | static void |
| 534 | update_domain_attr(struct sched_domain_attr *dattr, struct cpuset *c) |
| 535 | { |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 536 | if (dattr->relax_domain_level < c->relax_domain_level) |
| 537 | dattr->relax_domain_level = c->relax_domain_level; |
| 538 | return; |
| 539 | } |
| 540 | |
Lai Jiangshan | f539369 | 2008-07-29 22:33:22 -0700 | [diff] [blame] | 541 | static void |
| 542 | update_domain_attr_tree(struct sched_domain_attr *dattr, struct cpuset *c) |
| 543 | { |
| 544 | LIST_HEAD(q); |
| 545 | |
| 546 | list_add(&c->stack_list, &q); |
| 547 | while (!list_empty(&q)) { |
| 548 | struct cpuset *cp; |
| 549 | struct cgroup *cont; |
| 550 | struct cpuset *child; |
| 551 | |
| 552 | cp = list_first_entry(&q, struct cpuset, stack_list); |
| 553 | list_del(q.next); |
| 554 | |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 555 | if (cpumask_empty(cp->cpus_allowed)) |
Lai Jiangshan | f539369 | 2008-07-29 22:33:22 -0700 | [diff] [blame] | 556 | continue; |
| 557 | |
| 558 | if (is_sched_load_balance(cp)) |
| 559 | update_domain_attr(dattr, cp); |
| 560 | |
| 561 | list_for_each_entry(cont, &cp->css.cgroup->children, sibling) { |
| 562 | child = cgroup_cs(cont); |
| 563 | list_add_tail(&child->stack_list, &q); |
| 564 | } |
| 565 | } |
| 566 | } |
| 567 | |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 568 | /* |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 569 | * generate_sched_domains() |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 570 | * |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 571 | * This function builds a partial partition of the systems CPUs |
| 572 | * A 'partial partition' is a set of non-overlapping subsets whose |
| 573 | * union is a subset of that set. |
| 574 | * The output of this function needs to be passed to kernel/sched.c |
| 575 | * partition_sched_domains() routine, which will rebuild the scheduler's |
| 576 | * load balancing domains (sched domains) as specified by that partial |
| 577 | * partition. |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 578 | * |
Li Zefan | 45ce80f | 2009-01-15 13:50:59 -0800 | [diff] [blame] | 579 | * See "What is sched_load_balance" in Documentation/cgroups/cpusets.txt |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 580 | * for a background explanation of this. |
| 581 | * |
| 582 | * Does not return errors, on the theory that the callers of this |
| 583 | * routine would rather not worry about failures to rebuild sched |
| 584 | * domains when operating in the severe memory shortage situations |
| 585 | * that could cause allocation failures below. |
| 586 | * |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 587 | * Must be called with cgroup_lock held. |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 588 | * |
| 589 | * The three key local variables below are: |
Li Zefan | aeed682 | 2008-07-29 22:33:24 -0700 | [diff] [blame] | 590 | * q - a linked-list queue of cpuset pointers, used to implement a |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 591 | * top-down scan of all cpusets. This scan loads a pointer |
| 592 | * to each cpuset marked is_sched_load_balance into the |
| 593 | * array 'csa'. For our purposes, rebuilding the schedulers |
| 594 | * sched domains, we can ignore !is_sched_load_balance cpusets. |
| 595 | * csa - (for CpuSet Array) Array of pointers to all the cpusets |
| 596 | * that need to be load balanced, for convenient iterative |
| 597 | * access by the subsequent code that finds the best partition, |
| 598 | * i.e the set of domains (subsets) of CPUs such that the |
| 599 | * cpus_allowed of every cpuset marked is_sched_load_balance |
| 600 | * is a subset of one of these domains, while there are as |
| 601 | * many such domains as possible, each as small as possible. |
| 602 | * doms - Conversion of 'csa' to an array of cpumasks, for passing to |
| 603 | * the kernel/sched.c routine partition_sched_domains() in a |
| 604 | * convenient format, that can be easily compared to the prior |
| 605 | * value to determine what partition elements (sched domains) |
| 606 | * were changed (added or removed.) |
| 607 | * |
| 608 | * Finding the best partition (set of domains): |
| 609 | * The triple nested loops below over i, j, k scan over the |
| 610 | * load balanced cpusets (using the array of cpuset pointers in |
| 611 | * csa[]) looking for pairs of cpusets that have overlapping |
| 612 | * cpus_allowed, but which don't have the same 'pn' partition |
| 613 | * number and gives them in the same partition number. It keeps |
| 614 | * looping on the 'restart' label until it can no longer find |
| 615 | * any such pairs. |
| 616 | * |
| 617 | * The union of the cpus_allowed masks from the set of |
| 618 | * all cpusets having the same 'pn' value then form the one |
| 619 | * element of the partition (one sched domain) to be passed to |
| 620 | * partition_sched_domains(). |
| 621 | */ |
Li Zefan | 6af866a | 2009-01-07 18:08:45 -0800 | [diff] [blame] | 622 | /* FIXME: see the FIXME in partition_sched_domains() */ |
| 623 | static int generate_sched_domains(struct cpumask **domains, |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 624 | struct sched_domain_attr **attributes) |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 625 | { |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 626 | LIST_HEAD(q); /* queue of cpusets to be scanned */ |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 627 | struct cpuset *cp; /* scans q */ |
| 628 | struct cpuset **csa; /* array of all cpuset ptrs */ |
| 629 | int csn; /* how many cpuset ptrs in csa so far */ |
| 630 | int i, j, k; /* indices for partition finding loops */ |
Li Zefan | 6af866a | 2009-01-07 18:08:45 -0800 | [diff] [blame] | 631 | struct cpumask *doms; /* resulting partition; i.e. sched domains */ |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 632 | struct sched_domain_attr *dattr; /* attributes for custom domains */ |
Ingo Molnar | 1583715 | 2008-11-25 10:27:49 +0100 | [diff] [blame] | 633 | int ndoms = 0; /* number of sched domains in result */ |
Li Zefan | 6af866a | 2009-01-07 18:08:45 -0800 | [diff] [blame] | 634 | int nslot; /* next empty doms[] struct cpumask slot */ |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 635 | |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 636 | doms = NULL; |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 637 | dattr = NULL; |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 638 | csa = NULL; |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 639 | |
| 640 | /* Special case for the 99% of systems with one, full, sched domain */ |
| 641 | if (is_sched_load_balance(&top_cpuset)) { |
Li Zefan | 6af866a | 2009-01-07 18:08:45 -0800 | [diff] [blame] | 642 | doms = kmalloc(cpumask_size(), GFP_KERNEL); |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 643 | if (!doms) |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 644 | goto done; |
| 645 | |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 646 | dattr = kmalloc(sizeof(struct sched_domain_attr), GFP_KERNEL); |
| 647 | if (dattr) { |
| 648 | *dattr = SD_ATTR_INIT; |
Li Zefan | 93a6557 | 2008-07-29 22:33:23 -0700 | [diff] [blame] | 649 | update_domain_attr_tree(dattr, &top_cpuset); |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 650 | } |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 651 | cpumask_copy(doms, top_cpuset.cpus_allowed); |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 652 | |
| 653 | ndoms = 1; |
| 654 | goto done; |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 655 | } |
| 656 | |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 657 | csa = kmalloc(number_of_cpusets * sizeof(cp), GFP_KERNEL); |
| 658 | if (!csa) |
| 659 | goto done; |
| 660 | csn = 0; |
| 661 | |
Li Zefan | aeed682 | 2008-07-29 22:33:24 -0700 | [diff] [blame] | 662 | list_add(&top_cpuset.stack_list, &q); |
| 663 | while (!list_empty(&q)) { |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 664 | struct cgroup *cont; |
| 665 | struct cpuset *child; /* scans child cpusets of cp */ |
Lai Jiangshan | 489a539 | 2008-07-25 01:47:23 -0700 | [diff] [blame] | 666 | |
Li Zefan | aeed682 | 2008-07-29 22:33:24 -0700 | [diff] [blame] | 667 | cp = list_first_entry(&q, struct cpuset, stack_list); |
| 668 | list_del(q.next); |
| 669 | |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 670 | if (cpumask_empty(cp->cpus_allowed)) |
Lai Jiangshan | 489a539 | 2008-07-25 01:47:23 -0700 | [diff] [blame] | 671 | continue; |
| 672 | |
Lai Jiangshan | f539369 | 2008-07-29 22:33:22 -0700 | [diff] [blame] | 673 | /* |
| 674 | * All child cpusets contain a subset of the parent's cpus, so |
| 675 | * just skip them, and then we call update_domain_attr_tree() |
| 676 | * to calc relax_domain_level of the corresponding sched |
| 677 | * domain. |
| 678 | */ |
| 679 | if (is_sched_load_balance(cp)) { |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 680 | csa[csn++] = cp; |
Lai Jiangshan | f539369 | 2008-07-29 22:33:22 -0700 | [diff] [blame] | 681 | continue; |
| 682 | } |
Lai Jiangshan | 489a539 | 2008-07-25 01:47:23 -0700 | [diff] [blame] | 683 | |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 684 | list_for_each_entry(cont, &cp->css.cgroup->children, sibling) { |
| 685 | child = cgroup_cs(cont); |
Li Zefan | aeed682 | 2008-07-29 22:33:24 -0700 | [diff] [blame] | 686 | list_add_tail(&child->stack_list, &q); |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 687 | } |
| 688 | } |
| 689 | |
| 690 | for (i = 0; i < csn; i++) |
| 691 | csa[i]->pn = i; |
| 692 | ndoms = csn; |
| 693 | |
| 694 | restart: |
| 695 | /* Find the best partition (set of sched domains) */ |
| 696 | for (i = 0; i < csn; i++) { |
| 697 | struct cpuset *a = csa[i]; |
| 698 | int apn = a->pn; |
| 699 | |
| 700 | for (j = 0; j < csn; j++) { |
| 701 | struct cpuset *b = csa[j]; |
| 702 | int bpn = b->pn; |
| 703 | |
| 704 | if (apn != bpn && cpusets_overlap(a, b)) { |
| 705 | for (k = 0; k < csn; k++) { |
| 706 | struct cpuset *c = csa[k]; |
| 707 | |
| 708 | if (c->pn == bpn) |
| 709 | c->pn = apn; |
| 710 | } |
| 711 | ndoms--; /* one less element */ |
| 712 | goto restart; |
| 713 | } |
| 714 | } |
| 715 | } |
| 716 | |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 717 | /* |
| 718 | * Now we know how many domains to create. |
| 719 | * Convert <csn, csa> to <ndoms, doms> and populate cpu masks. |
| 720 | */ |
Li Zefan | 6af866a | 2009-01-07 18:08:45 -0800 | [diff] [blame] | 721 | doms = kmalloc(ndoms * cpumask_size(), GFP_KERNEL); |
Li Zefan | 700018e | 2008-11-18 14:02:03 +0800 | [diff] [blame] | 722 | if (!doms) |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 723 | goto done; |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 724 | |
| 725 | /* |
| 726 | * The rest of the code, including the scheduler, can deal with |
| 727 | * dattr==NULL case. No need to abort if alloc fails. |
| 728 | */ |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 729 | dattr = kmalloc(ndoms * sizeof(struct sched_domain_attr), GFP_KERNEL); |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 730 | |
| 731 | for (nslot = 0, i = 0; i < csn; i++) { |
| 732 | struct cpuset *a = csa[i]; |
Li Zefan | 6af866a | 2009-01-07 18:08:45 -0800 | [diff] [blame] | 733 | struct cpumask *dp; |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 734 | int apn = a->pn; |
| 735 | |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 736 | if (apn < 0) { |
| 737 | /* Skip completed partitions */ |
| 738 | continue; |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 739 | } |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 740 | |
| 741 | dp = doms + nslot; |
| 742 | |
| 743 | if (nslot == ndoms) { |
| 744 | static int warnings = 10; |
| 745 | if (warnings) { |
| 746 | printk(KERN_WARNING |
| 747 | "rebuild_sched_domains confused:" |
| 748 | " nslot %d, ndoms %d, csn %d, i %d," |
| 749 | " apn %d\n", |
| 750 | nslot, ndoms, csn, i, apn); |
| 751 | warnings--; |
| 752 | } |
| 753 | continue; |
| 754 | } |
| 755 | |
Li Zefan | 6af866a | 2009-01-07 18:08:45 -0800 | [diff] [blame] | 756 | cpumask_clear(dp); |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 757 | if (dattr) |
| 758 | *(dattr + nslot) = SD_ATTR_INIT; |
| 759 | for (j = i; j < csn; j++) { |
| 760 | struct cpuset *b = csa[j]; |
| 761 | |
| 762 | if (apn == b->pn) { |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 763 | cpumask_or(dp, dp, b->cpus_allowed); |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 764 | if (dattr) |
| 765 | update_domain_attr_tree(dattr + nslot, b); |
| 766 | |
| 767 | /* Done with this partition */ |
| 768 | b->pn = -1; |
| 769 | } |
| 770 | } |
| 771 | nslot++; |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 772 | } |
| 773 | BUG_ON(nslot != ndoms); |
| 774 | |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 775 | done: |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 776 | kfree(csa); |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 777 | |
Li Zefan | 700018e | 2008-11-18 14:02:03 +0800 | [diff] [blame] | 778 | /* |
| 779 | * Fallback to the default domain if kmalloc() failed. |
| 780 | * See comments in partition_sched_domains(). |
| 781 | */ |
| 782 | if (doms == NULL) |
| 783 | ndoms = 1; |
| 784 | |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 785 | *domains = doms; |
| 786 | *attributes = dattr; |
| 787 | return ndoms; |
| 788 | } |
| 789 | |
| 790 | /* |
| 791 | * Rebuild scheduler domains. |
| 792 | * |
| 793 | * Call with neither cgroup_mutex held nor within get_online_cpus(). |
| 794 | * Takes both cgroup_mutex and get_online_cpus(). |
| 795 | * |
| 796 | * Cannot be directly called from cpuset code handling changes |
| 797 | * to the cpuset pseudo-filesystem, because it cannot be called |
| 798 | * from code that already holds cgroup_mutex. |
| 799 | */ |
| 800 | static void do_rebuild_sched_domains(struct work_struct *unused) |
| 801 | { |
| 802 | struct sched_domain_attr *attr; |
Li Zefan | 6af866a | 2009-01-07 18:08:45 -0800 | [diff] [blame] | 803 | struct cpumask *doms; |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 804 | int ndoms; |
| 805 | |
| 806 | get_online_cpus(); |
| 807 | |
| 808 | /* Generate domain masks and attrs */ |
| 809 | cgroup_lock(); |
| 810 | ndoms = generate_sched_domains(&doms, &attr); |
| 811 | cgroup_unlock(); |
| 812 | |
| 813 | /* Have scheduler rebuild the domains */ |
| 814 | partition_sched_domains(ndoms, doms, attr); |
| 815 | |
| 816 | put_online_cpus(); |
| 817 | } |
| 818 | |
| 819 | static DECLARE_WORK(rebuild_sched_domains_work, do_rebuild_sched_domains); |
| 820 | |
| 821 | /* |
| 822 | * Rebuild scheduler domains, asynchronously via workqueue. |
| 823 | * |
| 824 | * If the flag 'sched_load_balance' of any cpuset with non-empty |
| 825 | * 'cpus' changes, or if the 'cpus' allowed changes in any cpuset |
| 826 | * which has that flag enabled, or if any cpuset with a non-empty |
| 827 | * 'cpus' is removed, then call this routine to rebuild the |
| 828 | * scheduler's dynamic sched domains. |
| 829 | * |
| 830 | * The rebuild_sched_domains() and partition_sched_domains() |
| 831 | * routines must nest cgroup_lock() inside get_online_cpus(), |
| 832 | * but such cpuset changes as these must nest that locking the |
| 833 | * other way, holding cgroup_lock() for much of the code. |
| 834 | * |
| 835 | * So in order to avoid an ABBA deadlock, the cpuset code handling |
| 836 | * these user changes delegates the actual sched domain rebuilding |
| 837 | * to a separate workqueue thread, which ends up processing the |
| 838 | * above do_rebuild_sched_domains() function. |
| 839 | */ |
| 840 | static void async_rebuild_sched_domains(void) |
| 841 | { |
Miao Xie | f90d411 | 2009-01-16 10:24:10 +0800 | [diff] [blame] | 842 | queue_work(cpuset_wq, &rebuild_sched_domains_work); |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 843 | } |
| 844 | |
| 845 | /* |
| 846 | * Accomplishes the same scheduler domain rebuild as the above |
| 847 | * async_rebuild_sched_domains(), however it directly calls the |
| 848 | * rebuild routine synchronously rather than calling it via an |
| 849 | * asynchronous work thread. |
| 850 | * |
| 851 | * This can only be called from code that is not holding |
| 852 | * cgroup_mutex (not nested in a cgroup_lock() call.) |
| 853 | */ |
| 854 | void rebuild_sched_domains(void) |
| 855 | { |
| 856 | do_rebuild_sched_domains(NULL); |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 857 | } |
| 858 | |
Cliff Wickman | 58f4790 | 2008-02-07 00:14:44 -0800 | [diff] [blame] | 859 | /** |
| 860 | * cpuset_test_cpumask - test a task's cpus_allowed versus its cpuset's |
| 861 | * @tsk: task to test |
| 862 | * @scan: struct cgroup_scanner contained in its struct cpuset_hotplug_scanner |
| 863 | * |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 864 | * Call with cgroup_mutex held. May take callback_mutex during call. |
Cliff Wickman | 58f4790 | 2008-02-07 00:14:44 -0800 | [diff] [blame] | 865 | * Called for each task in a cgroup by cgroup_scan_tasks(). |
| 866 | * Return nonzero if this tasks's cpus_allowed mask should be changed (in other |
| 867 | * words, if its mask is not equal to its cpuset's mask). |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 868 | */ |
Adrian Bunk | 9e0c914 | 2008-04-29 01:00:25 -0700 | [diff] [blame] | 869 | static int cpuset_test_cpumask(struct task_struct *tsk, |
| 870 | struct cgroup_scanner *scan) |
Cliff Wickman | 58f4790 | 2008-02-07 00:14:44 -0800 | [diff] [blame] | 871 | { |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 872 | return !cpumask_equal(&tsk->cpus_allowed, |
Cliff Wickman | 58f4790 | 2008-02-07 00:14:44 -0800 | [diff] [blame] | 873 | (cgroup_cs(scan->cg))->cpus_allowed); |
| 874 | } |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 875 | |
Cliff Wickman | 58f4790 | 2008-02-07 00:14:44 -0800 | [diff] [blame] | 876 | /** |
| 877 | * cpuset_change_cpumask - make a task's cpus_allowed the same as its cpuset's |
| 878 | * @tsk: task to test |
| 879 | * @scan: struct cgroup_scanner containing the cgroup of the task |
| 880 | * |
| 881 | * Called by cgroup_scan_tasks() for each task in a cgroup whose |
| 882 | * cpus_allowed mask needs to be changed. |
| 883 | * |
| 884 | * We don't need to re-check for the cgroup/cpuset membership, since we're |
| 885 | * holding cgroup_lock() at this point. |
| 886 | */ |
Adrian Bunk | 9e0c914 | 2008-04-29 01:00:25 -0700 | [diff] [blame] | 887 | static void cpuset_change_cpumask(struct task_struct *tsk, |
| 888 | struct cgroup_scanner *scan) |
Cliff Wickman | 58f4790 | 2008-02-07 00:14:44 -0800 | [diff] [blame] | 889 | { |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 890 | set_cpus_allowed_ptr(tsk, ((cgroup_cs(scan->cg))->cpus_allowed)); |
Cliff Wickman | 58f4790 | 2008-02-07 00:14:44 -0800 | [diff] [blame] | 891 | } |
| 892 | |
| 893 | /** |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 894 | * update_tasks_cpumask - Update the cpumasks of tasks in the cpuset. |
| 895 | * @cs: the cpuset in which each task's cpus_allowed mask needs to be changed |
Li Zefan | 4e74339 | 2008-09-13 02:33:08 -0700 | [diff] [blame] | 896 | * @heap: if NULL, defer allocating heap memory to cgroup_scan_tasks() |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 897 | * |
| 898 | * Called with cgroup_mutex held |
| 899 | * |
| 900 | * The cgroup_scan_tasks() function will scan all the tasks in a cgroup, |
| 901 | * calling callback functions for each. |
| 902 | * |
Li Zefan | 4e74339 | 2008-09-13 02:33:08 -0700 | [diff] [blame] | 903 | * No return value. It's guaranteed that cgroup_scan_tasks() always returns 0 |
| 904 | * if @heap != NULL. |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 905 | */ |
Li Zefan | 4e74339 | 2008-09-13 02:33:08 -0700 | [diff] [blame] | 906 | static void update_tasks_cpumask(struct cpuset *cs, struct ptr_heap *heap) |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 907 | { |
| 908 | struct cgroup_scanner scan; |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 909 | |
| 910 | scan.cg = cs->css.cgroup; |
| 911 | scan.test_task = cpuset_test_cpumask; |
| 912 | scan.process_task = cpuset_change_cpumask; |
Li Zefan | 4e74339 | 2008-09-13 02:33:08 -0700 | [diff] [blame] | 913 | scan.heap = heap; |
| 914 | cgroup_scan_tasks(&scan); |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 915 | } |
| 916 | |
| 917 | /** |
Cliff Wickman | 58f4790 | 2008-02-07 00:14:44 -0800 | [diff] [blame] | 918 | * update_cpumask - update the cpus_allowed mask of a cpuset and all tasks in it |
| 919 | * @cs: the cpuset to consider |
| 920 | * @buf: buffer of cpu numbers written to this cpuset |
| 921 | */ |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 922 | static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, |
| 923 | const char *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 924 | { |
Li Zefan | 4e74339 | 2008-09-13 02:33:08 -0700 | [diff] [blame] | 925 | struct ptr_heap heap; |
Cliff Wickman | 58f4790 | 2008-02-07 00:14:44 -0800 | [diff] [blame] | 926 | int retval; |
| 927 | int is_load_balanced; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 928 | |
Paul Jackson | 4c4d50f | 2006-08-27 01:23:51 -0700 | [diff] [blame] | 929 | /* top_cpuset.cpus_allowed tracks cpu_online_map; it's read-only */ |
| 930 | if (cs == &top_cpuset) |
| 931 | return -EACCES; |
| 932 | |
David Rientjes | 6f7f02e | 2007-05-08 00:31:43 -0700 | [diff] [blame] | 933 | /* |
Paul Jackson | c8d9c90 | 2008-02-07 00:14:46 -0800 | [diff] [blame] | 934 | * An empty cpus_allowed is ok only if the cpuset has no tasks. |
Paul Jackson | 020958b | 2007-10-18 23:40:21 -0700 | [diff] [blame] | 935 | * Since cpulist_parse() fails on an empty mask, we special case |
| 936 | * that parsing. The validate_change() call ensures that cpusets |
| 937 | * with tasks have cpus. |
David Rientjes | 6f7f02e | 2007-05-08 00:31:43 -0700 | [diff] [blame] | 938 | */ |
Paul Jackson | 020958b | 2007-10-18 23:40:21 -0700 | [diff] [blame] | 939 | if (!*buf) { |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 940 | cpumask_clear(trialcs->cpus_allowed); |
David Rientjes | 6f7f02e | 2007-05-08 00:31:43 -0700 | [diff] [blame] | 941 | } else { |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 942 | retval = cpulist_parse(buf, trialcs->cpus_allowed); |
David Rientjes | 6f7f02e | 2007-05-08 00:31:43 -0700 | [diff] [blame] | 943 | if (retval < 0) |
| 944 | return retval; |
Lai Jiangshan | 3734074 | 2008-06-05 22:46:32 -0700 | [diff] [blame] | 945 | |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 946 | if (!cpumask_subset(trialcs->cpus_allowed, cpu_online_mask)) |
Lai Jiangshan | 3734074 | 2008-06-05 22:46:32 -0700 | [diff] [blame] | 947 | return -EINVAL; |
David Rientjes | 6f7f02e | 2007-05-08 00:31:43 -0700 | [diff] [blame] | 948 | } |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 949 | retval = validate_change(cs, trialcs); |
Dinakar Guniguntala | 85d7b94 | 2005-06-25 14:57:34 -0700 | [diff] [blame] | 950 | if (retval < 0) |
| 951 | return retval; |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 952 | |
Paul Menage | 8707d8b | 2007-10-18 23:40:22 -0700 | [diff] [blame] | 953 | /* Nothing to do if the cpus didn't change */ |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 954 | if (cpumask_equal(cs->cpus_allowed, trialcs->cpus_allowed)) |
Paul Menage | 8707d8b | 2007-10-18 23:40:22 -0700 | [diff] [blame] | 955 | return 0; |
Cliff Wickman | 58f4790 | 2008-02-07 00:14:44 -0800 | [diff] [blame] | 956 | |
Li Zefan | 4e74339 | 2008-09-13 02:33:08 -0700 | [diff] [blame] | 957 | retval = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL); |
| 958 | if (retval) |
| 959 | return retval; |
| 960 | |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 961 | is_load_balanced = is_sched_load_balance(trialcs); |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 962 | |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 963 | mutex_lock(&callback_mutex); |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 964 | cpumask_copy(cs->cpus_allowed, trialcs->cpus_allowed); |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 965 | mutex_unlock(&callback_mutex); |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 966 | |
Paul Menage | 8707d8b | 2007-10-18 23:40:22 -0700 | [diff] [blame] | 967 | /* |
| 968 | * Scan tasks in the cpuset, and update the cpumasks of any |
Cliff Wickman | 58f4790 | 2008-02-07 00:14:44 -0800 | [diff] [blame] | 969 | * that need an update. |
Paul Menage | 8707d8b | 2007-10-18 23:40:22 -0700 | [diff] [blame] | 970 | */ |
Li Zefan | 4e74339 | 2008-09-13 02:33:08 -0700 | [diff] [blame] | 971 | update_tasks_cpumask(cs, &heap); |
| 972 | |
| 973 | heap_free(&heap); |
Cliff Wickman | 58f4790 | 2008-02-07 00:14:44 -0800 | [diff] [blame] | 974 | |
Paul Menage | 8707d8b | 2007-10-18 23:40:22 -0700 | [diff] [blame] | 975 | if (is_load_balanced) |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 976 | async_rebuild_sched_domains(); |
Dinakar Guniguntala | 85d7b94 | 2005-06-25 14:57:34 -0700 | [diff] [blame] | 977 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 978 | } |
| 979 | |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 980 | /* |
Paul Jackson | e4e364e | 2006-03-31 02:30:52 -0800 | [diff] [blame] | 981 | * cpuset_migrate_mm |
| 982 | * |
| 983 | * Migrate memory region from one set of nodes to another. |
| 984 | * |
| 985 | * Temporarilly set tasks mems_allowed to target nodes of migration, |
| 986 | * so that the migration code can allocate pages on these nodes. |
| 987 | * |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 988 | * Call holding cgroup_mutex, so current's cpuset won't change |
Paul Jackson | c8d9c90 | 2008-02-07 00:14:46 -0800 | [diff] [blame] | 989 | * during this call, as manage_mutex holds off any cpuset_attach() |
Paul Jackson | e4e364e | 2006-03-31 02:30:52 -0800 | [diff] [blame] | 990 | * calls. Therefore we don't need to take task_lock around the |
| 991 | * call to guarantee_online_mems(), as we know no one is changing |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 992 | * our task's cpuset. |
Paul Jackson | e4e364e | 2006-03-31 02:30:52 -0800 | [diff] [blame] | 993 | * |
| 994 | * Hold callback_mutex around the two modifications of our tasks |
| 995 | * mems_allowed to synchronize with cpuset_mems_allowed(). |
| 996 | * |
| 997 | * While the mm_struct we are migrating is typically from some |
| 998 | * other task, the task_struct mems_allowed that we are hacking |
| 999 | * is for our current task, which must allocate new pages for that |
| 1000 | * migrating memory region. |
| 1001 | * |
| 1002 | * We call cpuset_update_task_memory_state() before hacking |
| 1003 | * our tasks mems_allowed, so that we are assured of being in |
| 1004 | * sync with our tasks cpuset, and in particular, callbacks to |
| 1005 | * cpuset_update_task_memory_state() from nested page allocations |
| 1006 | * won't see any mismatch of our cpuset and task mems_generation |
| 1007 | * values, so won't overwrite our hacked tasks mems_allowed |
| 1008 | * nodemask. |
| 1009 | */ |
| 1010 | |
| 1011 | static void cpuset_migrate_mm(struct mm_struct *mm, const nodemask_t *from, |
| 1012 | const nodemask_t *to) |
| 1013 | { |
| 1014 | struct task_struct *tsk = current; |
| 1015 | |
| 1016 | cpuset_update_task_memory_state(); |
| 1017 | |
| 1018 | mutex_lock(&callback_mutex); |
| 1019 | tsk->mems_allowed = *to; |
| 1020 | mutex_unlock(&callback_mutex); |
| 1021 | |
| 1022 | do_migrate_pages(mm, from, to, MPOL_MF_MOVE_ALL); |
| 1023 | |
| 1024 | mutex_lock(&callback_mutex); |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1025 | guarantee_online_mems(task_cs(tsk),&tsk->mems_allowed); |
Paul Jackson | e4e364e | 2006-03-31 02:30:52 -0800 | [diff] [blame] | 1026 | mutex_unlock(&callback_mutex); |
| 1027 | } |
| 1028 | |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1029 | static void *cpuset_being_rebound; |
| 1030 | |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 1031 | /** |
| 1032 | * update_tasks_nodemask - Update the nodemasks of tasks in the cpuset. |
| 1033 | * @cs: the cpuset in which each task's mems_allowed mask needs to be changed |
| 1034 | * @oldmem: old mems_allowed of cpuset cs |
| 1035 | * |
| 1036 | * Called with cgroup_mutex held |
| 1037 | * Return 0 if successful, -errno if not. |
| 1038 | */ |
| 1039 | static int update_tasks_nodemask(struct cpuset *cs, const nodemask_t *oldmem) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1040 | { |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1041 | struct task_struct *p; |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1042 | struct mm_struct **mmarray; |
| 1043 | int i, n, ntasks; |
Paul Jackson | 04c19fa | 2006-01-08 01:02:00 -0800 | [diff] [blame] | 1044 | int migrate; |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1045 | int fudge; |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1046 | struct cgroup_iter it; |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 1047 | int retval; |
Paul Jackson | 59dac16 | 2006-01-08 01:01:52 -0800 | [diff] [blame] | 1048 | |
Lee Schermerhorn | 846a16b | 2008-04-28 02:13:09 -0700 | [diff] [blame] | 1049 | cpuset_being_rebound = cs; /* causes mpol_dup() rebind */ |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1050 | |
| 1051 | fudge = 10; /* spare mmarray[] slots */ |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 1052 | fudge += cpumask_weight(cs->cpus_allowed);/* imagine 1 fork-bomb/cpu */ |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1053 | retval = -ENOMEM; |
| 1054 | |
| 1055 | /* |
| 1056 | * Allocate mmarray[] to hold mm reference for each task |
| 1057 | * in cpuset cs. Can't kmalloc GFP_KERNEL while holding |
| 1058 | * tasklist_lock. We could use GFP_ATOMIC, but with a |
| 1059 | * few more lines of code, we can retry until we get a big |
| 1060 | * enough mmarray[] w/o using GFP_ATOMIC. |
| 1061 | */ |
| 1062 | while (1) { |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1063 | ntasks = cgroup_task_count(cs->css.cgroup); /* guess */ |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1064 | ntasks += fudge; |
| 1065 | mmarray = kmalloc(ntasks * sizeof(*mmarray), GFP_KERNEL); |
| 1066 | if (!mmarray) |
| 1067 | goto done; |
Paul Menage | c2aef33 | 2007-07-15 23:40:11 -0700 | [diff] [blame] | 1068 | read_lock(&tasklist_lock); /* block fork */ |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1069 | if (cgroup_task_count(cs->css.cgroup) <= ntasks) |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1070 | break; /* got enough */ |
Paul Menage | c2aef33 | 2007-07-15 23:40:11 -0700 | [diff] [blame] | 1071 | read_unlock(&tasklist_lock); /* try again */ |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1072 | kfree(mmarray); |
| 1073 | } |
| 1074 | |
| 1075 | n = 0; |
| 1076 | |
| 1077 | /* Load up mmarray[] with mm reference for each task in cpuset. */ |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1078 | cgroup_iter_start(cs->css.cgroup, &it); |
| 1079 | while ((p = cgroup_iter_next(cs->css.cgroup, &it))) { |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1080 | struct mm_struct *mm; |
| 1081 | |
| 1082 | if (n >= ntasks) { |
| 1083 | printk(KERN_WARNING |
| 1084 | "Cpuset mempolicy rebind incomplete.\n"); |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1085 | break; |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1086 | } |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1087 | mm = get_task_mm(p); |
| 1088 | if (!mm) |
| 1089 | continue; |
| 1090 | mmarray[n++] = mm; |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1091 | } |
| 1092 | cgroup_iter_end(cs->css.cgroup, &it); |
Paul Menage | c2aef33 | 2007-07-15 23:40:11 -0700 | [diff] [blame] | 1093 | read_unlock(&tasklist_lock); |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1094 | |
| 1095 | /* |
| 1096 | * Now that we've dropped the tasklist spinlock, we can |
| 1097 | * rebind the vma mempolicies of each mm in mmarray[] to their |
| 1098 | * new cpuset, and release that mm. The mpol_rebind_mm() |
| 1099 | * call takes mmap_sem, which we couldn't take while holding |
Lee Schermerhorn | 846a16b | 2008-04-28 02:13:09 -0700 | [diff] [blame] | 1100 | * tasklist_lock. Forks can happen again now - the mpol_dup() |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1101 | * cpuset_being_rebound check will catch such forks, and rebind |
| 1102 | * their vma mempolicies too. Because we still hold the global |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 1103 | * cgroup_mutex, we know that no other rebind effort will |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1104 | * be contending for the global variable cpuset_being_rebound. |
| 1105 | * It's ok if we rebind the same mm twice; mpol_rebind_mm() |
Paul Jackson | 04c19fa | 2006-01-08 01:02:00 -0800 | [diff] [blame] | 1106 | * is idempotent. Also migrate pages in each mm to new nodes. |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1107 | */ |
Paul Jackson | 04c19fa | 2006-01-08 01:02:00 -0800 | [diff] [blame] | 1108 | migrate = is_memory_migrate(cs); |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1109 | for (i = 0; i < n; i++) { |
| 1110 | struct mm_struct *mm = mmarray[i]; |
| 1111 | |
| 1112 | mpol_rebind_mm(mm, &cs->mems_allowed); |
Paul Jackson | e4e364e | 2006-03-31 02:30:52 -0800 | [diff] [blame] | 1113 | if (migrate) |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 1114 | cpuset_migrate_mm(mm, oldmem, &cs->mems_allowed); |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1115 | mmput(mm); |
| 1116 | } |
| 1117 | |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 1118 | /* We're done rebinding vmas to this cpuset's new mems_allowed. */ |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1119 | kfree(mmarray); |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1120 | cpuset_being_rebound = NULL; |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1121 | retval = 0; |
Paul Jackson | 59dac16 | 2006-01-08 01:01:52 -0800 | [diff] [blame] | 1122 | done: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1123 | return retval; |
| 1124 | } |
| 1125 | |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 1126 | /* |
| 1127 | * Handle user request to change the 'mems' memory placement |
| 1128 | * of a cpuset. Needs to validate the request, update the |
| 1129 | * cpusets mems_allowed and mems_generation, and for each |
| 1130 | * task in the cpuset, rebind any vma mempolicies and if |
| 1131 | * the cpuset is marked 'memory_migrate', migrate the tasks |
| 1132 | * pages to the new memory. |
| 1133 | * |
| 1134 | * Call with cgroup_mutex held. May take callback_mutex during call. |
| 1135 | * Will take tasklist_lock, scan tasklist for tasks in cpuset cs, |
| 1136 | * lock each such tasks mm->mmap_sem, scan its vma's and rebind |
| 1137 | * their mempolicies to the cpusets new mems_allowed. |
| 1138 | */ |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1139 | static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs, |
| 1140 | const char *buf) |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 1141 | { |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 1142 | nodemask_t oldmem; |
| 1143 | int retval; |
| 1144 | |
| 1145 | /* |
| 1146 | * top_cpuset.mems_allowed tracks node_stats[N_HIGH_MEMORY]; |
| 1147 | * it's read-only |
| 1148 | */ |
| 1149 | if (cs == &top_cpuset) |
| 1150 | return -EACCES; |
| 1151 | |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 1152 | /* |
| 1153 | * An empty mems_allowed is ok iff there are no tasks in the cpuset. |
| 1154 | * Since nodelist_parse() fails on an empty mask, we special case |
| 1155 | * that parsing. The validate_change() call ensures that cpusets |
| 1156 | * with tasks have memory. |
| 1157 | */ |
| 1158 | if (!*buf) { |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1159 | nodes_clear(trialcs->mems_allowed); |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 1160 | } else { |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1161 | retval = nodelist_parse(buf, trialcs->mems_allowed); |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 1162 | if (retval < 0) |
| 1163 | goto done; |
| 1164 | |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1165 | if (!nodes_subset(trialcs->mems_allowed, |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 1166 | node_states[N_HIGH_MEMORY])) |
| 1167 | return -EINVAL; |
| 1168 | } |
| 1169 | oldmem = cs->mems_allowed; |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1170 | if (nodes_equal(oldmem, trialcs->mems_allowed)) { |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 1171 | retval = 0; /* Too easy - nothing to do */ |
| 1172 | goto done; |
| 1173 | } |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1174 | retval = validate_change(cs, trialcs); |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 1175 | if (retval < 0) |
| 1176 | goto done; |
| 1177 | |
| 1178 | mutex_lock(&callback_mutex); |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1179 | cs->mems_allowed = trialcs->mems_allowed; |
Miao Xie | 0b2f630 | 2008-07-25 01:47:21 -0700 | [diff] [blame] | 1180 | cs->mems_generation = cpuset_mems_generation++; |
| 1181 | mutex_unlock(&callback_mutex); |
| 1182 | |
| 1183 | retval = update_tasks_nodemask(cs, &oldmem); |
| 1184 | done: |
| 1185 | return retval; |
| 1186 | } |
| 1187 | |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1188 | int current_cpuset_is_being_rebound(void) |
| 1189 | { |
| 1190 | return task_cs(current) == cpuset_being_rebound; |
| 1191 | } |
| 1192 | |
Paul Menage | 5be7a47 | 2008-05-06 20:42:41 -0700 | [diff] [blame] | 1193 | static int update_relax_domain_level(struct cpuset *cs, s64 val) |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 1194 | { |
Li Zefan | 30e0e17 | 2008-05-13 10:27:17 +0800 | [diff] [blame] | 1195 | if (val < -1 || val >= SD_LV_MAX) |
| 1196 | return -EINVAL; |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 1197 | |
| 1198 | if (val != cs->relax_domain_level) { |
| 1199 | cs->relax_domain_level = val; |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 1200 | if (!cpumask_empty(cs->cpus_allowed) && |
| 1201 | is_sched_load_balance(cs)) |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 1202 | async_rebuild_sched_domains(); |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 1203 | } |
| 1204 | |
| 1205 | return 0; |
| 1206 | } |
| 1207 | |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 1208 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1209 | * update_flag - read a 0 or a 1 in a file and update associated flag |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1210 | * bit: the bit to update (see cpuset_flagbits_t) |
| 1211 | * cs: the cpuset to update |
| 1212 | * turning_on: whether the flag is being set or cleared |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 1213 | * |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 1214 | * Call with cgroup_mutex held. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1215 | */ |
| 1216 | |
Paul Menage | 700fe1a | 2008-04-29 01:00:00 -0700 | [diff] [blame] | 1217 | static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs, |
| 1218 | int turning_on) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1219 | { |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1220 | struct cpuset *trialcs; |
Paul Jackson | 607717a | 2007-10-16 01:27:43 -0700 | [diff] [blame] | 1221 | int err; |
Rakib Mullick | 40b6a76 | 2008-10-18 20:28:18 -0700 | [diff] [blame] | 1222 | int balance_flag_changed; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1223 | |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1224 | trialcs = alloc_trial_cpuset(cs); |
| 1225 | if (!trialcs) |
| 1226 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1227 | |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1228 | if (turning_on) |
| 1229 | set_bit(bit, &trialcs->flags); |
| 1230 | else |
| 1231 | clear_bit(bit, &trialcs->flags); |
| 1232 | |
| 1233 | err = validate_change(cs, trialcs); |
Dinakar Guniguntala | 85d7b94 | 2005-06-25 14:57:34 -0700 | [diff] [blame] | 1234 | if (err < 0) |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1235 | goto out; |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 1236 | |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 1237 | balance_flag_changed = (is_sched_load_balance(cs) != |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1238 | is_sched_load_balance(trialcs)); |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 1239 | |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 1240 | mutex_lock(&callback_mutex); |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1241 | cs->flags = trialcs->flags; |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 1242 | mutex_unlock(&callback_mutex); |
Dinakar Guniguntala | 85d7b94 | 2005-06-25 14:57:34 -0700 | [diff] [blame] | 1243 | |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 1244 | if (!cpumask_empty(trialcs->cpus_allowed) && balance_flag_changed) |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 1245 | async_rebuild_sched_domains(); |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 1246 | |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1247 | out: |
| 1248 | free_trial_cpuset(trialcs); |
| 1249 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1250 | } |
| 1251 | |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 1252 | /* |
Adrian Bunk | 80f7228 | 2006-06-30 18:27:16 +0200 | [diff] [blame] | 1253 | * Frequency meter - How fast is some event occurring? |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 1254 | * |
| 1255 | * These routines manage a digitally filtered, constant time based, |
| 1256 | * event frequency meter. There are four routines: |
| 1257 | * fmeter_init() - initialize a frequency meter. |
| 1258 | * fmeter_markevent() - called each time the event happens. |
| 1259 | * fmeter_getrate() - returns the recent rate of such events. |
| 1260 | * fmeter_update() - internal routine used to update fmeter. |
| 1261 | * |
| 1262 | * A common data structure is passed to each of these routines, |
| 1263 | * which is used to keep track of the state required to manage the |
| 1264 | * frequency meter and its digital filter. |
| 1265 | * |
| 1266 | * The filter works on the number of events marked per unit time. |
| 1267 | * The filter is single-pole low-pass recursive (IIR). The time unit |
| 1268 | * is 1 second. Arithmetic is done using 32-bit integers scaled to |
| 1269 | * simulate 3 decimal digits of precision (multiplied by 1000). |
| 1270 | * |
| 1271 | * With an FM_COEF of 933, and a time base of 1 second, the filter |
| 1272 | * has a half-life of 10 seconds, meaning that if the events quit |
| 1273 | * happening, then the rate returned from the fmeter_getrate() |
| 1274 | * will be cut in half each 10 seconds, until it converges to zero. |
| 1275 | * |
| 1276 | * It is not worth doing a real infinitely recursive filter. If more |
| 1277 | * than FM_MAXTICKS ticks have elapsed since the last filter event, |
| 1278 | * just compute FM_MAXTICKS ticks worth, by which point the level |
| 1279 | * will be stable. |
| 1280 | * |
| 1281 | * Limit the count of unprocessed events to FM_MAXCNT, so as to avoid |
| 1282 | * arithmetic overflow in the fmeter_update() routine. |
| 1283 | * |
| 1284 | * Given the simple 32 bit integer arithmetic used, this meter works |
| 1285 | * best for reporting rates between one per millisecond (msec) and |
| 1286 | * one per 32 (approx) seconds. At constant rates faster than one |
| 1287 | * per msec it maxes out at values just under 1,000,000. At constant |
| 1288 | * rates between one per msec, and one per second it will stabilize |
| 1289 | * to a value N*1000, where N is the rate of events per second. |
| 1290 | * At constant rates between one per second and one per 32 seconds, |
| 1291 | * it will be choppy, moving up on the seconds that have an event, |
| 1292 | * and then decaying until the next event. At rates slower than |
| 1293 | * about one in 32 seconds, it decays all the way back to zero between |
| 1294 | * each event. |
| 1295 | */ |
| 1296 | |
| 1297 | #define FM_COEF 933 /* coefficient for half-life of 10 secs */ |
| 1298 | #define FM_MAXTICKS ((time_t)99) /* useless computing more ticks than this */ |
| 1299 | #define FM_MAXCNT 1000000 /* limit cnt to avoid overflow */ |
| 1300 | #define FM_SCALE 1000 /* faux fixed point scale */ |
| 1301 | |
| 1302 | /* Initialize a frequency meter */ |
| 1303 | static void fmeter_init(struct fmeter *fmp) |
| 1304 | { |
| 1305 | fmp->cnt = 0; |
| 1306 | fmp->val = 0; |
| 1307 | fmp->time = 0; |
| 1308 | spin_lock_init(&fmp->lock); |
| 1309 | } |
| 1310 | |
| 1311 | /* Internal meter update - process cnt events and update value */ |
| 1312 | static void fmeter_update(struct fmeter *fmp) |
| 1313 | { |
| 1314 | time_t now = get_seconds(); |
| 1315 | time_t ticks = now - fmp->time; |
| 1316 | |
| 1317 | if (ticks == 0) |
| 1318 | return; |
| 1319 | |
| 1320 | ticks = min(FM_MAXTICKS, ticks); |
| 1321 | while (ticks-- > 0) |
| 1322 | fmp->val = (FM_COEF * fmp->val) / FM_SCALE; |
| 1323 | fmp->time = now; |
| 1324 | |
| 1325 | fmp->val += ((FM_SCALE - FM_COEF) * fmp->cnt) / FM_SCALE; |
| 1326 | fmp->cnt = 0; |
| 1327 | } |
| 1328 | |
| 1329 | /* Process any previous ticks, then bump cnt by one (times scale). */ |
| 1330 | static void fmeter_markevent(struct fmeter *fmp) |
| 1331 | { |
| 1332 | spin_lock(&fmp->lock); |
| 1333 | fmeter_update(fmp); |
| 1334 | fmp->cnt = min(FM_MAXCNT, fmp->cnt + FM_SCALE); |
| 1335 | spin_unlock(&fmp->lock); |
| 1336 | } |
| 1337 | |
| 1338 | /* Process any previous ticks, then return current value. */ |
| 1339 | static int fmeter_getrate(struct fmeter *fmp) |
| 1340 | { |
| 1341 | int val; |
| 1342 | |
| 1343 | spin_lock(&fmp->lock); |
| 1344 | fmeter_update(fmp); |
| 1345 | val = fmp->val; |
| 1346 | spin_unlock(&fmp->lock); |
| 1347 | return val; |
| 1348 | } |
| 1349 | |
Li Zefan | 2341d1b | 2009-01-07 18:08:42 -0800 | [diff] [blame] | 1350 | /* Protected by cgroup_lock */ |
| 1351 | static cpumask_var_t cpus_attach; |
| 1352 | |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 1353 | /* Called by cgroups to determine if a cpuset is usable; cgroup_mutex held */ |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1354 | static int cpuset_can_attach(struct cgroup_subsys *ss, |
| 1355 | struct cgroup *cont, struct task_struct *tsk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1356 | { |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1357 | struct cpuset *cs = cgroup_cs(cont); |
Li Zefan | 5771f0a | 2009-01-07 18:08:41 -0800 | [diff] [blame] | 1358 | int ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1359 | |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 1360 | if (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1361 | return -ENOSPC; |
David Rientjes | 9985b0b | 2008-06-05 12:57:11 -0700 | [diff] [blame] | 1362 | |
Li Zefan | 5771f0a | 2009-01-07 18:08:41 -0800 | [diff] [blame] | 1363 | if (tsk->flags & PF_THREAD_BOUND) { |
David Rientjes | 9985b0b | 2008-06-05 12:57:11 -0700 | [diff] [blame] | 1364 | mutex_lock(&callback_mutex); |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 1365 | if (!cpumask_equal(&tsk->cpus_allowed, cs->cpus_allowed)) |
Li Zefan | 5771f0a | 2009-01-07 18:08:41 -0800 | [diff] [blame] | 1366 | ret = -EINVAL; |
David Rientjes | 9985b0b | 2008-06-05 12:57:11 -0700 | [diff] [blame] | 1367 | mutex_unlock(&callback_mutex); |
David Rientjes | 9985b0b | 2008-06-05 12:57:11 -0700 | [diff] [blame] | 1368 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1369 | |
Li Zefan | 5771f0a | 2009-01-07 18:08:41 -0800 | [diff] [blame] | 1370 | return ret < 0 ? ret : security_task_setscheduler(tsk, 0, NULL); |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1371 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1372 | |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1373 | static void cpuset_attach(struct cgroup_subsys *ss, |
| 1374 | struct cgroup *cont, struct cgroup *oldcont, |
| 1375 | struct task_struct *tsk) |
| 1376 | { |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1377 | nodemask_t from, to; |
| 1378 | struct mm_struct *mm; |
| 1379 | struct cpuset *cs = cgroup_cs(cont); |
| 1380 | struct cpuset *oldcs = cgroup_cs(oldcont); |
David Rientjes | 9985b0b | 2008-06-05 12:57:11 -0700 | [diff] [blame] | 1381 | int err; |
David Quigley | 22fb52d | 2006-06-23 02:04:00 -0700 | [diff] [blame] | 1382 | |
Miao Xie | f5813d9 | 2009-01-07 18:08:40 -0800 | [diff] [blame] | 1383 | if (cs == &top_cpuset) { |
Li Zefan | 2341d1b | 2009-01-07 18:08:42 -0800 | [diff] [blame] | 1384 | cpumask_copy(cpus_attach, cpu_possible_mask); |
Miao Xie | f5813d9 | 2009-01-07 18:08:40 -0800 | [diff] [blame] | 1385 | } else { |
| 1386 | mutex_lock(&callback_mutex); |
Li Zefan | 2341d1b | 2009-01-07 18:08:42 -0800 | [diff] [blame] | 1387 | guarantee_online_cpus(cs, cpus_attach); |
Miao Xie | f5813d9 | 2009-01-07 18:08:40 -0800 | [diff] [blame] | 1388 | mutex_unlock(&callback_mutex); |
| 1389 | } |
Li Zefan | 2341d1b | 2009-01-07 18:08:42 -0800 | [diff] [blame] | 1390 | err = set_cpus_allowed_ptr(tsk, cpus_attach); |
David Rientjes | 9985b0b | 2008-06-05 12:57:11 -0700 | [diff] [blame] | 1391 | if (err) |
| 1392 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1393 | |
Paul Jackson | 45b07ef | 2006-01-08 01:00:56 -0800 | [diff] [blame] | 1394 | from = oldcs->mems_allowed; |
| 1395 | to = cs->mems_allowed; |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1396 | mm = get_task_mm(tsk); |
| 1397 | if (mm) { |
| 1398 | mpol_rebind_mm(mm, &to); |
Paul Jackson | 2741a55 | 2006-03-31 02:30:51 -0800 | [diff] [blame] | 1399 | if (is_memory_migrate(cs)) |
Paul Jackson | e4e364e | 2006-03-31 02:30:52 -0800 | [diff] [blame] | 1400 | cpuset_migrate_mm(mm, &from, &to); |
Paul Jackson | 4225399 | 2006-01-08 01:01:59 -0800 | [diff] [blame] | 1401 | mmput(mm); |
| 1402 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1403 | } |
| 1404 | |
| 1405 | /* The various types of files and directories in a cpuset file system */ |
| 1406 | |
| 1407 | typedef enum { |
Paul Jackson | 45b07ef | 2006-01-08 01:00:56 -0800 | [diff] [blame] | 1408 | FILE_MEMORY_MIGRATE, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1409 | FILE_CPULIST, |
| 1410 | FILE_MEMLIST, |
| 1411 | FILE_CPU_EXCLUSIVE, |
| 1412 | FILE_MEM_EXCLUSIVE, |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1413 | FILE_MEM_HARDWALL, |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 1414 | FILE_SCHED_LOAD_BALANCE, |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 1415 | FILE_SCHED_RELAX_DOMAIN_LEVEL, |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 1416 | FILE_MEMORY_PRESSURE_ENABLED, |
| 1417 | FILE_MEMORY_PRESSURE, |
Paul Jackson | 825a46a | 2006-03-24 03:16:03 -0800 | [diff] [blame] | 1418 | FILE_SPREAD_PAGE, |
| 1419 | FILE_SPREAD_SLAB, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1420 | } cpuset_filetype_t; |
| 1421 | |
Paul Menage | 700fe1a | 2008-04-29 01:00:00 -0700 | [diff] [blame] | 1422 | static int cpuset_write_u64(struct cgroup *cgrp, struct cftype *cft, u64 val) |
| 1423 | { |
| 1424 | int retval = 0; |
| 1425 | struct cpuset *cs = cgroup_cs(cgrp); |
| 1426 | cpuset_filetype_t type = cft->private; |
| 1427 | |
Paul Menage | e371239 | 2008-07-25 01:47:02 -0700 | [diff] [blame] | 1428 | if (!cgroup_lock_live_group(cgrp)) |
Paul Menage | 700fe1a | 2008-04-29 01:00:00 -0700 | [diff] [blame] | 1429 | return -ENODEV; |
Paul Menage | 700fe1a | 2008-04-29 01:00:00 -0700 | [diff] [blame] | 1430 | |
| 1431 | switch (type) { |
| 1432 | case FILE_CPU_EXCLUSIVE: |
| 1433 | retval = update_flag(CS_CPU_EXCLUSIVE, cs, val); |
| 1434 | break; |
| 1435 | case FILE_MEM_EXCLUSIVE: |
| 1436 | retval = update_flag(CS_MEM_EXCLUSIVE, cs, val); |
| 1437 | break; |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1438 | case FILE_MEM_HARDWALL: |
| 1439 | retval = update_flag(CS_MEM_HARDWALL, cs, val); |
| 1440 | break; |
Paul Menage | 700fe1a | 2008-04-29 01:00:00 -0700 | [diff] [blame] | 1441 | case FILE_SCHED_LOAD_BALANCE: |
| 1442 | retval = update_flag(CS_SCHED_LOAD_BALANCE, cs, val); |
| 1443 | break; |
| 1444 | case FILE_MEMORY_MIGRATE: |
| 1445 | retval = update_flag(CS_MEMORY_MIGRATE, cs, val); |
| 1446 | break; |
| 1447 | case FILE_MEMORY_PRESSURE_ENABLED: |
| 1448 | cpuset_memory_pressure_enabled = !!val; |
| 1449 | break; |
| 1450 | case FILE_MEMORY_PRESSURE: |
| 1451 | retval = -EACCES; |
| 1452 | break; |
| 1453 | case FILE_SPREAD_PAGE: |
| 1454 | retval = update_flag(CS_SPREAD_PAGE, cs, val); |
| 1455 | cs->mems_generation = cpuset_mems_generation++; |
| 1456 | break; |
| 1457 | case FILE_SPREAD_SLAB: |
| 1458 | retval = update_flag(CS_SPREAD_SLAB, cs, val); |
| 1459 | cs->mems_generation = cpuset_mems_generation++; |
| 1460 | break; |
| 1461 | default: |
| 1462 | retval = -EINVAL; |
| 1463 | break; |
| 1464 | } |
| 1465 | cgroup_unlock(); |
| 1466 | return retval; |
| 1467 | } |
| 1468 | |
Paul Menage | 5be7a47 | 2008-05-06 20:42:41 -0700 | [diff] [blame] | 1469 | static int cpuset_write_s64(struct cgroup *cgrp, struct cftype *cft, s64 val) |
| 1470 | { |
| 1471 | int retval = 0; |
| 1472 | struct cpuset *cs = cgroup_cs(cgrp); |
| 1473 | cpuset_filetype_t type = cft->private; |
| 1474 | |
Paul Menage | e371239 | 2008-07-25 01:47:02 -0700 | [diff] [blame] | 1475 | if (!cgroup_lock_live_group(cgrp)) |
Paul Menage | 5be7a47 | 2008-05-06 20:42:41 -0700 | [diff] [blame] | 1476 | return -ENODEV; |
Paul Menage | e371239 | 2008-07-25 01:47:02 -0700 | [diff] [blame] | 1477 | |
Paul Menage | 5be7a47 | 2008-05-06 20:42:41 -0700 | [diff] [blame] | 1478 | switch (type) { |
| 1479 | case FILE_SCHED_RELAX_DOMAIN_LEVEL: |
| 1480 | retval = update_relax_domain_level(cs, val); |
| 1481 | break; |
| 1482 | default: |
| 1483 | retval = -EINVAL; |
| 1484 | break; |
| 1485 | } |
| 1486 | cgroup_unlock(); |
| 1487 | return retval; |
| 1488 | } |
| 1489 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1490 | /* |
Paul Menage | e371239 | 2008-07-25 01:47:02 -0700 | [diff] [blame] | 1491 | * Common handling for a write to a "cpus" or "mems" file. |
| 1492 | */ |
| 1493 | static int cpuset_write_resmask(struct cgroup *cgrp, struct cftype *cft, |
| 1494 | const char *buf) |
| 1495 | { |
| 1496 | int retval = 0; |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1497 | struct cpuset *cs = cgroup_cs(cgrp); |
| 1498 | struct cpuset *trialcs; |
Paul Menage | e371239 | 2008-07-25 01:47:02 -0700 | [diff] [blame] | 1499 | |
| 1500 | if (!cgroup_lock_live_group(cgrp)) |
| 1501 | return -ENODEV; |
| 1502 | |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1503 | trialcs = alloc_trial_cpuset(cs); |
| 1504 | if (!trialcs) |
| 1505 | return -ENOMEM; |
| 1506 | |
Paul Menage | e371239 | 2008-07-25 01:47:02 -0700 | [diff] [blame] | 1507 | switch (cft->private) { |
| 1508 | case FILE_CPULIST: |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1509 | retval = update_cpumask(cs, trialcs, buf); |
Paul Menage | e371239 | 2008-07-25 01:47:02 -0700 | [diff] [blame] | 1510 | break; |
| 1511 | case FILE_MEMLIST: |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1512 | retval = update_nodemask(cs, trialcs, buf); |
Paul Menage | e371239 | 2008-07-25 01:47:02 -0700 | [diff] [blame] | 1513 | break; |
| 1514 | default: |
| 1515 | retval = -EINVAL; |
| 1516 | break; |
| 1517 | } |
Li Zefan | 645fcc9 | 2009-01-07 18:08:43 -0800 | [diff] [blame] | 1518 | |
| 1519 | free_trial_cpuset(trialcs); |
Paul Menage | e371239 | 2008-07-25 01:47:02 -0700 | [diff] [blame] | 1520 | cgroup_unlock(); |
| 1521 | return retval; |
| 1522 | } |
| 1523 | |
| 1524 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1525 | * These ascii lists should be read in a single call, by using a user |
| 1526 | * buffer large enough to hold the entire map. If read in smaller |
| 1527 | * chunks, there is no guarantee of atomicity. Since the display format |
| 1528 | * used, list of ranges of sequential numbers, is variable length, |
| 1529 | * and since these maps can change value dynamically, one could read |
| 1530 | * gibberish by doing partial reads while a list was changing. |
| 1531 | * A single large read to a buffer that crosses a page boundary is |
| 1532 | * ok, because the result being copied to user land is not recomputed |
| 1533 | * across a page fault. |
| 1534 | */ |
| 1535 | |
| 1536 | static int cpuset_sprintf_cpulist(char *page, struct cpuset *cs) |
| 1537 | { |
Li Zefan | 5a7625d | 2009-01-07 18:08:41 -0800 | [diff] [blame] | 1538 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1539 | |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 1540 | mutex_lock(&callback_mutex); |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 1541 | ret = cpulist_scnprintf(page, PAGE_SIZE, cs->cpus_allowed); |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 1542 | mutex_unlock(&callback_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1543 | |
Li Zefan | 5a7625d | 2009-01-07 18:08:41 -0800 | [diff] [blame] | 1544 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1545 | } |
| 1546 | |
| 1547 | static int cpuset_sprintf_memlist(char *page, struct cpuset *cs) |
| 1548 | { |
| 1549 | nodemask_t mask; |
| 1550 | |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 1551 | mutex_lock(&callback_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1552 | mask = cs->mems_allowed; |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 1553 | mutex_unlock(&callback_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1554 | |
| 1555 | return nodelist_scnprintf(page, PAGE_SIZE, mask); |
| 1556 | } |
| 1557 | |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1558 | static ssize_t cpuset_common_file_read(struct cgroup *cont, |
| 1559 | struct cftype *cft, |
| 1560 | struct file *file, |
| 1561 | char __user *buf, |
| 1562 | size_t nbytes, loff_t *ppos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1563 | { |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1564 | struct cpuset *cs = cgroup_cs(cont); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1565 | cpuset_filetype_t type = cft->private; |
| 1566 | char *page; |
| 1567 | ssize_t retval = 0; |
| 1568 | char *s; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1569 | |
Mel Gorman | e12ba74 | 2007-10-16 01:25:52 -0700 | [diff] [blame] | 1570 | if (!(page = (char *)__get_free_page(GFP_TEMPORARY))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1571 | return -ENOMEM; |
| 1572 | |
| 1573 | s = page; |
| 1574 | |
| 1575 | switch (type) { |
| 1576 | case FILE_CPULIST: |
| 1577 | s += cpuset_sprintf_cpulist(s, cs); |
| 1578 | break; |
| 1579 | case FILE_MEMLIST: |
| 1580 | s += cpuset_sprintf_memlist(s, cs); |
| 1581 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1582 | default: |
| 1583 | retval = -EINVAL; |
| 1584 | goto out; |
| 1585 | } |
| 1586 | *s++ = '\n'; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1587 | |
Al Viro | eacaa1f | 2005-09-30 03:26:43 +0100 | [diff] [blame] | 1588 | retval = simple_read_from_buffer(buf, nbytes, ppos, page, s - page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1589 | out: |
| 1590 | free_page((unsigned long)page); |
| 1591 | return retval; |
| 1592 | } |
| 1593 | |
Paul Menage | 700fe1a | 2008-04-29 01:00:00 -0700 | [diff] [blame] | 1594 | static u64 cpuset_read_u64(struct cgroup *cont, struct cftype *cft) |
| 1595 | { |
| 1596 | struct cpuset *cs = cgroup_cs(cont); |
| 1597 | cpuset_filetype_t type = cft->private; |
| 1598 | switch (type) { |
| 1599 | case FILE_CPU_EXCLUSIVE: |
| 1600 | return is_cpu_exclusive(cs); |
| 1601 | case FILE_MEM_EXCLUSIVE: |
| 1602 | return is_mem_exclusive(cs); |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1603 | case FILE_MEM_HARDWALL: |
| 1604 | return is_mem_hardwall(cs); |
Paul Menage | 700fe1a | 2008-04-29 01:00:00 -0700 | [diff] [blame] | 1605 | case FILE_SCHED_LOAD_BALANCE: |
| 1606 | return is_sched_load_balance(cs); |
| 1607 | case FILE_MEMORY_MIGRATE: |
| 1608 | return is_memory_migrate(cs); |
| 1609 | case FILE_MEMORY_PRESSURE_ENABLED: |
| 1610 | return cpuset_memory_pressure_enabled; |
| 1611 | case FILE_MEMORY_PRESSURE: |
| 1612 | return fmeter_getrate(&cs->fmeter); |
| 1613 | case FILE_SPREAD_PAGE: |
| 1614 | return is_spread_page(cs); |
| 1615 | case FILE_SPREAD_SLAB: |
| 1616 | return is_spread_slab(cs); |
| 1617 | default: |
| 1618 | BUG(); |
| 1619 | } |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 1620 | |
| 1621 | /* Unreachable but makes gcc happy */ |
| 1622 | return 0; |
Paul Menage | 700fe1a | 2008-04-29 01:00:00 -0700 | [diff] [blame] | 1623 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1624 | |
Paul Menage | 5be7a47 | 2008-05-06 20:42:41 -0700 | [diff] [blame] | 1625 | static s64 cpuset_read_s64(struct cgroup *cont, struct cftype *cft) |
| 1626 | { |
| 1627 | struct cpuset *cs = cgroup_cs(cont); |
| 1628 | cpuset_filetype_t type = cft->private; |
| 1629 | switch (type) { |
| 1630 | case FILE_SCHED_RELAX_DOMAIN_LEVEL: |
| 1631 | return cs->relax_domain_level; |
| 1632 | default: |
| 1633 | BUG(); |
| 1634 | } |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 1635 | |
| 1636 | /* Unrechable but makes gcc happy */ |
| 1637 | return 0; |
Paul Menage | 5be7a47 | 2008-05-06 20:42:41 -0700 | [diff] [blame] | 1638 | } |
| 1639 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1640 | |
| 1641 | /* |
| 1642 | * for the common functions, 'private' gives the type of file |
| 1643 | */ |
| 1644 | |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1645 | static struct cftype files[] = { |
| 1646 | { |
| 1647 | .name = "cpus", |
| 1648 | .read = cpuset_common_file_read, |
Paul Menage | e371239 | 2008-07-25 01:47:02 -0700 | [diff] [blame] | 1649 | .write_string = cpuset_write_resmask, |
| 1650 | .max_write_len = (100U + 6 * NR_CPUS), |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1651 | .private = FILE_CPULIST, |
| 1652 | }, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1653 | |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1654 | { |
| 1655 | .name = "mems", |
| 1656 | .read = cpuset_common_file_read, |
Paul Menage | e371239 | 2008-07-25 01:47:02 -0700 | [diff] [blame] | 1657 | .write_string = cpuset_write_resmask, |
| 1658 | .max_write_len = (100U + 6 * MAX_NUMNODES), |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1659 | .private = FILE_MEMLIST, |
| 1660 | }, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1661 | |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1662 | { |
| 1663 | .name = "cpu_exclusive", |
| 1664 | .read_u64 = cpuset_read_u64, |
| 1665 | .write_u64 = cpuset_write_u64, |
| 1666 | .private = FILE_CPU_EXCLUSIVE, |
| 1667 | }, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1668 | |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1669 | { |
| 1670 | .name = "mem_exclusive", |
| 1671 | .read_u64 = cpuset_read_u64, |
| 1672 | .write_u64 = cpuset_write_u64, |
| 1673 | .private = FILE_MEM_EXCLUSIVE, |
| 1674 | }, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1675 | |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1676 | { |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1677 | .name = "mem_hardwall", |
| 1678 | .read_u64 = cpuset_read_u64, |
| 1679 | .write_u64 = cpuset_write_u64, |
| 1680 | .private = FILE_MEM_HARDWALL, |
| 1681 | }, |
| 1682 | |
| 1683 | { |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1684 | .name = "sched_load_balance", |
| 1685 | .read_u64 = cpuset_read_u64, |
| 1686 | .write_u64 = cpuset_write_u64, |
| 1687 | .private = FILE_SCHED_LOAD_BALANCE, |
| 1688 | }, |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 1689 | |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1690 | { |
| 1691 | .name = "sched_relax_domain_level", |
Paul Menage | 5be7a47 | 2008-05-06 20:42:41 -0700 | [diff] [blame] | 1692 | .read_s64 = cpuset_read_s64, |
| 1693 | .write_s64 = cpuset_write_s64, |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1694 | .private = FILE_SCHED_RELAX_DOMAIN_LEVEL, |
| 1695 | }, |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 1696 | |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1697 | { |
| 1698 | .name = "memory_migrate", |
| 1699 | .read_u64 = cpuset_read_u64, |
| 1700 | .write_u64 = cpuset_write_u64, |
| 1701 | .private = FILE_MEMORY_MIGRATE, |
| 1702 | }, |
| 1703 | |
| 1704 | { |
| 1705 | .name = "memory_pressure", |
| 1706 | .read_u64 = cpuset_read_u64, |
| 1707 | .write_u64 = cpuset_write_u64, |
| 1708 | .private = FILE_MEMORY_PRESSURE, |
| 1709 | }, |
| 1710 | |
| 1711 | { |
| 1712 | .name = "memory_spread_page", |
| 1713 | .read_u64 = cpuset_read_u64, |
| 1714 | .write_u64 = cpuset_write_u64, |
| 1715 | .private = FILE_SPREAD_PAGE, |
| 1716 | }, |
| 1717 | |
| 1718 | { |
| 1719 | .name = "memory_spread_slab", |
| 1720 | .read_u64 = cpuset_read_u64, |
| 1721 | .write_u64 = cpuset_write_u64, |
| 1722 | .private = FILE_SPREAD_SLAB, |
| 1723 | }, |
Paul Jackson | 45b07ef | 2006-01-08 01:00:56 -0800 | [diff] [blame] | 1724 | }; |
| 1725 | |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 1726 | static struct cftype cft_memory_pressure_enabled = { |
| 1727 | .name = "memory_pressure_enabled", |
Paul Menage | 700fe1a | 2008-04-29 01:00:00 -0700 | [diff] [blame] | 1728 | .read_u64 = cpuset_read_u64, |
| 1729 | .write_u64 = cpuset_write_u64, |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 1730 | .private = FILE_MEMORY_PRESSURE_ENABLED, |
| 1731 | }; |
| 1732 | |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1733 | static int cpuset_populate(struct cgroup_subsys *ss, struct cgroup *cont) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1734 | { |
| 1735 | int err; |
| 1736 | |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1737 | err = cgroup_add_files(cont, ss, files, ARRAY_SIZE(files)); |
| 1738 | if (err) |
Paul Jackson | 825a46a | 2006-03-24 03:16:03 -0800 | [diff] [blame] | 1739 | return err; |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1740 | /* memory_pressure_enabled is in root cpuset only */ |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1741 | if (!cont->parent) |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1742 | err = cgroup_add_file(cont, ss, |
Paul Menage | addf2c7 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 1743 | &cft_memory_pressure_enabled); |
| 1744 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1745 | } |
| 1746 | |
| 1747 | /* |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1748 | * post_clone() is called at the end of cgroup_clone(). |
| 1749 | * 'cgroup' was just created automatically as a result of |
| 1750 | * a cgroup_clone(), and the current task is about to |
| 1751 | * be moved into 'cgroup'. |
| 1752 | * |
| 1753 | * Currently we refuse to set up the cgroup - thereby |
| 1754 | * refusing the task to be entered, and as a result refusing |
| 1755 | * the sys_unshare() or clone() which initiated it - if any |
| 1756 | * sibling cpusets have exclusive cpus or mem. |
| 1757 | * |
| 1758 | * If this becomes a problem for some users who wish to |
| 1759 | * allow that scenario, then cpuset_post_clone() could be |
| 1760 | * changed to grant parent->cpus_allowed-sibling_cpus_exclusive |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 1761 | * (and likewise for mems) to the new cgroup. Called with cgroup_mutex |
| 1762 | * held. |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1763 | */ |
| 1764 | static void cpuset_post_clone(struct cgroup_subsys *ss, |
| 1765 | struct cgroup *cgroup) |
| 1766 | { |
| 1767 | struct cgroup *parent, *child; |
| 1768 | struct cpuset *cs, *parent_cs; |
| 1769 | |
| 1770 | parent = cgroup->parent; |
| 1771 | list_for_each_entry(child, &parent->children, sibling) { |
| 1772 | cs = cgroup_cs(child); |
| 1773 | if (is_mem_exclusive(cs) || is_cpu_exclusive(cs)) |
| 1774 | return; |
| 1775 | } |
| 1776 | cs = cgroup_cs(cgroup); |
| 1777 | parent_cs = cgroup_cs(parent); |
| 1778 | |
| 1779 | cs->mems_allowed = parent_cs->mems_allowed; |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 1780 | cpumask_copy(cs->cpus_allowed, parent_cs->cpus_allowed); |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1781 | return; |
| 1782 | } |
| 1783 | |
| 1784 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1785 | * cpuset_create - create a cpuset |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 1786 | * ss: cpuset cgroup subsystem |
| 1787 | * cont: control group that the new cpuset will be part of |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1788 | */ |
| 1789 | |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1790 | static struct cgroup_subsys_state *cpuset_create( |
| 1791 | struct cgroup_subsys *ss, |
| 1792 | struct cgroup *cont) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1793 | { |
| 1794 | struct cpuset *cs; |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1795 | struct cpuset *parent; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1796 | |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1797 | if (!cont->parent) { |
| 1798 | /* This is early initialization for the top cgroup */ |
| 1799 | top_cpuset.mems_generation = cpuset_mems_generation++; |
| 1800 | return &top_cpuset.css; |
| 1801 | } |
| 1802 | parent = cgroup_cs(cont->parent); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1803 | cs = kmalloc(sizeof(*cs), GFP_KERNEL); |
| 1804 | if (!cs) |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1805 | return ERR_PTR(-ENOMEM); |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 1806 | if (!alloc_cpumask_var(&cs->cpus_allowed, GFP_KERNEL)) { |
| 1807 | kfree(cs); |
| 1808 | return ERR_PTR(-ENOMEM); |
| 1809 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1810 | |
Paul Jackson | cf2a473c | 2006-01-08 01:01:54 -0800 | [diff] [blame] | 1811 | cpuset_update_task_memory_state(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1812 | cs->flags = 0; |
Paul Jackson | 825a46a | 2006-03-24 03:16:03 -0800 | [diff] [blame] | 1813 | if (is_spread_page(parent)) |
| 1814 | set_bit(CS_SPREAD_PAGE, &cs->flags); |
| 1815 | if (is_spread_slab(parent)) |
| 1816 | set_bit(CS_SPREAD_SLAB, &cs->flags); |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 1817 | set_bit(CS_SCHED_LOAD_BALANCE, &cs->flags); |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 1818 | cpumask_clear(cs->cpus_allowed); |
Mike Travis | f9a86fc | 2008-04-04 18:11:07 -0700 | [diff] [blame] | 1819 | nodes_clear(cs->mems_allowed); |
Paul Jackson | 151a442 | 2006-03-24 03:16:11 -0800 | [diff] [blame] | 1820 | cs->mems_generation = cpuset_mems_generation++; |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 1821 | fmeter_init(&cs->fmeter); |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 1822 | cs->relax_domain_level = -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1823 | |
| 1824 | cs->parent = parent; |
Paul Jackson | 202f72d | 2006-01-08 01:01:57 -0800 | [diff] [blame] | 1825 | number_of_cpusets++; |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1826 | return &cs->css ; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1827 | } |
| 1828 | |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 1829 | /* |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 1830 | * If the cpuset being removed has its flag 'sched_load_balance' |
| 1831 | * enabled, then simulate turning sched_load_balance off, which |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 1832 | * will call async_rebuild_sched_domains(). |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 1833 | */ |
| 1834 | |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1835 | static void cpuset_destroy(struct cgroup_subsys *ss, struct cgroup *cont) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1836 | { |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1837 | struct cpuset *cs = cgroup_cs(cont); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1838 | |
Paul Jackson | cf2a473c | 2006-01-08 01:01:54 -0800 | [diff] [blame] | 1839 | cpuset_update_task_memory_state(); |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 1840 | |
| 1841 | if (is_sched_load_balance(cs)) |
Paul Menage | 700fe1a | 2008-04-29 01:00:00 -0700 | [diff] [blame] | 1842 | update_flag(CS_SCHED_LOAD_BALANCE, cs, 0); |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 1843 | |
Paul Jackson | 202f72d | 2006-01-08 01:01:57 -0800 | [diff] [blame] | 1844 | number_of_cpusets--; |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 1845 | free_cpumask_var(cs->cpus_allowed); |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1846 | kfree(cs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1847 | } |
| 1848 | |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1849 | struct cgroup_subsys cpuset_subsys = { |
| 1850 | .name = "cpuset", |
| 1851 | .create = cpuset_create, |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 1852 | .destroy = cpuset_destroy, |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1853 | .can_attach = cpuset_can_attach, |
| 1854 | .attach = cpuset_attach, |
| 1855 | .populate = cpuset_populate, |
| 1856 | .post_clone = cpuset_post_clone, |
| 1857 | .subsys_id = cpuset_subsys_id, |
| 1858 | .early_init = 1, |
| 1859 | }; |
| 1860 | |
Paul Jackson | c417f02 | 2006-01-08 01:02:01 -0800 | [diff] [blame] | 1861 | /* |
| 1862 | * cpuset_init_early - just enough so that the calls to |
| 1863 | * cpuset_update_task_memory_state() in early init code |
| 1864 | * are harmless. |
| 1865 | */ |
| 1866 | |
| 1867 | int __init cpuset_init_early(void) |
| 1868 | { |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 1869 | alloc_bootmem_cpumask_var(&top_cpuset.cpus_allowed); |
| 1870 | |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1871 | top_cpuset.mems_generation = cpuset_mems_generation++; |
Paul Jackson | c417f02 | 2006-01-08 01:02:01 -0800 | [diff] [blame] | 1872 | return 0; |
| 1873 | } |
| 1874 | |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1875 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1876 | /** |
| 1877 | * cpuset_init - initialize cpusets at system boot |
| 1878 | * |
| 1879 | * Description: Initialize top_cpuset and the cpuset internal file system, |
| 1880 | **/ |
| 1881 | |
| 1882 | int __init cpuset_init(void) |
| 1883 | { |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1884 | int err = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1885 | |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 1886 | cpumask_setall(top_cpuset.cpus_allowed); |
Mike Travis | f9a86fc | 2008-04-04 18:11:07 -0700 | [diff] [blame] | 1887 | nodes_setall(top_cpuset.mems_allowed); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1888 | |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 1889 | fmeter_init(&top_cpuset.fmeter); |
Paul Jackson | 151a442 | 2006-03-24 03:16:11 -0800 | [diff] [blame] | 1890 | top_cpuset.mems_generation = cpuset_mems_generation++; |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 1891 | set_bit(CS_SCHED_LOAD_BALANCE, &top_cpuset.flags); |
Hidetoshi Seto | 1d3504f | 2008-04-15 14:04:23 +0900 | [diff] [blame] | 1892 | top_cpuset.relax_domain_level = -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1893 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1894 | err = register_filesystem(&cpuset_fs_type); |
| 1895 | if (err < 0) |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1896 | return err; |
| 1897 | |
Li Zefan | 2341d1b | 2009-01-07 18:08:42 -0800 | [diff] [blame] | 1898 | if (!alloc_cpumask_var(&cpus_attach, GFP_KERNEL)) |
| 1899 | BUG(); |
| 1900 | |
Paul Jackson | 202f72d | 2006-01-08 01:01:57 -0800 | [diff] [blame] | 1901 | number_of_cpusets = 1; |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 1902 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1903 | } |
| 1904 | |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 1905 | /** |
| 1906 | * cpuset_do_move_task - move a given task to another cpuset |
| 1907 | * @tsk: pointer to task_struct the task to move |
| 1908 | * @scan: struct cgroup_scanner contained in its struct cpuset_hotplug_scanner |
| 1909 | * |
| 1910 | * Called by cgroup_scan_tasks() for each task in a cgroup. |
| 1911 | * Return nonzero to stop the walk through the tasks. |
| 1912 | */ |
Adrian Bunk | 9e0c914 | 2008-04-29 01:00:25 -0700 | [diff] [blame] | 1913 | static void cpuset_do_move_task(struct task_struct *tsk, |
| 1914 | struct cgroup_scanner *scan) |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 1915 | { |
| 1916 | struct cpuset_hotplug_scanner *chsp; |
| 1917 | |
| 1918 | chsp = container_of(scan, struct cpuset_hotplug_scanner, scan); |
| 1919 | cgroup_attach_task(chsp->to, tsk); |
| 1920 | } |
| 1921 | |
| 1922 | /** |
| 1923 | * move_member_tasks_to_cpuset - move tasks from one cpuset to another |
| 1924 | * @from: cpuset in which the tasks currently reside |
| 1925 | * @to: cpuset to which the tasks will be moved |
| 1926 | * |
Paul Jackson | c8d9c90 | 2008-02-07 00:14:46 -0800 | [diff] [blame] | 1927 | * Called with cgroup_mutex held |
| 1928 | * callback_mutex must not be held, as cpuset_attach() will take it. |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 1929 | * |
| 1930 | * The cgroup_scan_tasks() function will scan all the tasks in a cgroup, |
| 1931 | * calling callback functions for each. |
| 1932 | */ |
| 1933 | static void move_member_tasks_to_cpuset(struct cpuset *from, struct cpuset *to) |
| 1934 | { |
| 1935 | struct cpuset_hotplug_scanner scan; |
| 1936 | |
| 1937 | scan.scan.cg = from->css.cgroup; |
| 1938 | scan.scan.test_task = NULL; /* select all tasks in cgroup */ |
| 1939 | scan.scan.process_task = cpuset_do_move_task; |
| 1940 | scan.scan.heap = NULL; |
| 1941 | scan.to = to->css.cgroup; |
| 1942 | |
Lai Jiangshan | da5ef6b | 2008-07-25 01:47:25 -0700 | [diff] [blame] | 1943 | if (cgroup_scan_tasks(&scan.scan)) |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 1944 | printk(KERN_ERR "move_member_tasks_to_cpuset: " |
| 1945 | "cgroup_scan_tasks failed\n"); |
| 1946 | } |
| 1947 | |
Paul Jackson | b1aac8b | 2006-09-29 02:01:17 -0700 | [diff] [blame] | 1948 | /* |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 1949 | * If CPU and/or memory hotplug handlers, below, unplug any CPUs |
Paul Jackson | b1aac8b | 2006-09-29 02:01:17 -0700 | [diff] [blame] | 1950 | * or memory nodes, we need to walk over the cpuset hierarchy, |
| 1951 | * removing that CPU or node from all cpusets. If this removes the |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 1952 | * last CPU or node from a cpuset, then move the tasks in the empty |
| 1953 | * cpuset to its next-highest non-empty parent. |
Paul Jackson | b1aac8b | 2006-09-29 02:01:17 -0700 | [diff] [blame] | 1954 | * |
Paul Jackson | c8d9c90 | 2008-02-07 00:14:46 -0800 | [diff] [blame] | 1955 | * Called with cgroup_mutex held |
| 1956 | * callback_mutex must not be held, as cpuset_attach() will take it. |
Paul Jackson | b1aac8b | 2006-09-29 02:01:17 -0700 | [diff] [blame] | 1957 | */ |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 1958 | static void remove_tasks_in_empty_cpuset(struct cpuset *cs) |
Paul Jackson | b1aac8b | 2006-09-29 02:01:17 -0700 | [diff] [blame] | 1959 | { |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 1960 | struct cpuset *parent; |
Paul Jackson | b1aac8b | 2006-09-29 02:01:17 -0700 | [diff] [blame] | 1961 | |
Paul Jackson | c8d9c90 | 2008-02-07 00:14:46 -0800 | [diff] [blame] | 1962 | /* |
| 1963 | * The cgroup's css_sets list is in use if there are tasks |
| 1964 | * in the cpuset; the list is empty if there are none; |
| 1965 | * the cs->css.refcnt seems always 0. |
| 1966 | */ |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 1967 | if (list_empty(&cs->css.cgroup->css_sets)) |
| 1968 | return; |
| 1969 | |
| 1970 | /* |
| 1971 | * Find its next-highest non-empty parent, (top cpuset |
| 1972 | * has online cpus, so can't be empty). |
| 1973 | */ |
| 1974 | parent = cs->parent; |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 1975 | while (cpumask_empty(parent->cpus_allowed) || |
Paul Jackson | b450129 | 2008-02-07 00:14:47 -0800 | [diff] [blame] | 1976 | nodes_empty(parent->mems_allowed)) |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 1977 | parent = parent->parent; |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 1978 | |
| 1979 | move_member_tasks_to_cpuset(cs, parent); |
| 1980 | } |
| 1981 | |
| 1982 | /* |
| 1983 | * Walk the specified cpuset subtree and look for empty cpusets. |
| 1984 | * The tasks of such cpuset must be moved to a parent cpuset. |
| 1985 | * |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 1986 | * Called with cgroup_mutex held. We take callback_mutex to modify |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 1987 | * cpus_allowed and mems_allowed. |
| 1988 | * |
| 1989 | * This walk processes the tree from top to bottom, completing one layer |
| 1990 | * before dropping down to the next. It always processes a node before |
| 1991 | * any of its children. |
| 1992 | * |
| 1993 | * For now, since we lack memory hot unplug, we'll never see a cpuset |
| 1994 | * that has tasks along with an empty 'mems'. But if we did see such |
| 1995 | * a cpuset, we'd handle it just like we do if its 'cpus' was empty. |
| 1996 | */ |
Frederic Weisbecker | d294eb8 | 2008-10-03 12:10:10 +0200 | [diff] [blame] | 1997 | static void scan_for_empty_cpusets(struct cpuset *root) |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 1998 | { |
Li Zefan | 8d1e626 | 2008-07-29 22:33:21 -0700 | [diff] [blame] | 1999 | LIST_HEAD(queue); |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 2000 | struct cpuset *cp; /* scans cpusets being updated */ |
| 2001 | struct cpuset *child; /* scans child cpusets of cp */ |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 2002 | struct cgroup *cont; |
Miao Xie | f9b4fb8 | 2008-07-25 01:47:22 -0700 | [diff] [blame] | 2003 | nodemask_t oldmems; |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 2004 | |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 2005 | list_add_tail((struct list_head *)&root->stack_list, &queue); |
| 2006 | |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 2007 | while (!list_empty(&queue)) { |
Li Zefan | 8d1e626 | 2008-07-29 22:33:21 -0700 | [diff] [blame] | 2008 | cp = list_first_entry(&queue, struct cpuset, stack_list); |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 2009 | list_del(queue.next); |
| 2010 | list_for_each_entry(cont, &cp->css.cgroup->children, sibling) { |
| 2011 | child = cgroup_cs(cont); |
| 2012 | list_add_tail(&child->stack_list, &queue); |
| 2013 | } |
Paul Jackson | b450129 | 2008-02-07 00:14:47 -0800 | [diff] [blame] | 2014 | |
| 2015 | /* Continue past cpusets with all cpus, mems online */ |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 2016 | if (cpumask_subset(cp->cpus_allowed, cpu_online_mask) && |
Paul Jackson | b450129 | 2008-02-07 00:14:47 -0800 | [diff] [blame] | 2017 | nodes_subset(cp->mems_allowed, node_states[N_HIGH_MEMORY])) |
| 2018 | continue; |
| 2019 | |
Miao Xie | f9b4fb8 | 2008-07-25 01:47:22 -0700 | [diff] [blame] | 2020 | oldmems = cp->mems_allowed; |
| 2021 | |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 2022 | /* Remove offline cpus and mems from this cpuset. */ |
Paul Jackson | b450129 | 2008-02-07 00:14:47 -0800 | [diff] [blame] | 2023 | mutex_lock(&callback_mutex); |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 2024 | cpumask_and(cp->cpus_allowed, cp->cpus_allowed, |
| 2025 | cpu_online_mask); |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 2026 | nodes_and(cp->mems_allowed, cp->mems_allowed, |
| 2027 | node_states[N_HIGH_MEMORY]); |
Paul Jackson | b450129 | 2008-02-07 00:14:47 -0800 | [diff] [blame] | 2028 | mutex_unlock(&callback_mutex); |
| 2029 | |
| 2030 | /* Move tasks from the empty cpuset to a parent */ |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 2031 | if (cpumask_empty(cp->cpus_allowed) || |
Paul Jackson | b450129 | 2008-02-07 00:14:47 -0800 | [diff] [blame] | 2032 | nodes_empty(cp->mems_allowed)) |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 2033 | remove_tasks_in_empty_cpuset(cp); |
Miao Xie | f9b4fb8 | 2008-07-25 01:47:22 -0700 | [diff] [blame] | 2034 | else { |
Li Zefan | 4e74339 | 2008-09-13 02:33:08 -0700 | [diff] [blame] | 2035 | update_tasks_cpumask(cp, NULL); |
Miao Xie | f9b4fb8 | 2008-07-25 01:47:22 -0700 | [diff] [blame] | 2036 | update_tasks_nodemask(cp, &oldmems); |
| 2037 | } |
Cliff Wickman | 956db3c | 2008-02-07 00:14:43 -0800 | [diff] [blame] | 2038 | } |
Paul Jackson | b1aac8b | 2006-09-29 02:01:17 -0700 | [diff] [blame] | 2039 | } |
| 2040 | |
| 2041 | /* |
Paul Jackson | 4c4d50f | 2006-08-27 01:23:51 -0700 | [diff] [blame] | 2042 | * The top_cpuset tracks what CPUs and Memory Nodes are online, |
| 2043 | * period. This is necessary in order to make cpusets transparent |
| 2044 | * (of no affect) on systems that are actively using CPU hotplug |
| 2045 | * but making no active use of cpusets. |
| 2046 | * |
Paul Jackson | 38837fc | 2006-09-29 02:01:16 -0700 | [diff] [blame] | 2047 | * This routine ensures that top_cpuset.cpus_allowed tracks |
| 2048 | * cpu_online_map on each CPU hotplug (cpuhp) event. |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 2049 | * |
| 2050 | * Called within get_online_cpus(). Needs to call cgroup_lock() |
| 2051 | * before calling generate_sched_domains(). |
Paul Jackson | 4c4d50f | 2006-08-27 01:23:51 -0700 | [diff] [blame] | 2052 | */ |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 2053 | static int cpuset_track_online_cpus(struct notifier_block *unused_nb, |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 2054 | unsigned long phase, void *unused_cpu) |
Paul Jackson | 4c4d50f | 2006-08-27 01:23:51 -0700 | [diff] [blame] | 2055 | { |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 2056 | struct sched_domain_attr *attr; |
Li Zefan | 6af866a | 2009-01-07 18:08:45 -0800 | [diff] [blame] | 2057 | struct cpumask *doms; |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 2058 | int ndoms; |
| 2059 | |
Dmitry Adamushko | 3e84050 | 2008-07-13 02:10:29 +0200 | [diff] [blame] | 2060 | switch (phase) { |
Dmitry Adamushko | 3e84050 | 2008-07-13 02:10:29 +0200 | [diff] [blame] | 2061 | case CPU_ONLINE: |
| 2062 | case CPU_ONLINE_FROZEN: |
| 2063 | case CPU_DEAD: |
| 2064 | case CPU_DEAD_FROZEN: |
Dmitry Adamushko | 3e84050 | 2008-07-13 02:10:29 +0200 | [diff] [blame] | 2065 | break; |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 2066 | |
Dmitry Adamushko | 3e84050 | 2008-07-13 02:10:29 +0200 | [diff] [blame] | 2067 | default: |
Avi Kivity | ac07675 | 2007-05-24 12:33:15 +0300 | [diff] [blame] | 2068 | return NOTIFY_DONE; |
Dmitry Adamushko | 3e84050 | 2008-07-13 02:10:29 +0200 | [diff] [blame] | 2069 | } |
Avi Kivity | ac07675 | 2007-05-24 12:33:15 +0300 | [diff] [blame] | 2070 | |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 2071 | cgroup_lock(); |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 2072 | cpumask_copy(top_cpuset.cpus_allowed, cpu_online_mask); |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 2073 | scan_for_empty_cpusets(&top_cpuset); |
| 2074 | ndoms = generate_sched_domains(&doms, &attr); |
| 2075 | cgroup_unlock(); |
| 2076 | |
| 2077 | /* Have scheduler rebuild the domains */ |
| 2078 | partition_sched_domains(ndoms, doms, attr); |
| 2079 | |
Dmitry Adamushko | 3e84050 | 2008-07-13 02:10:29 +0200 | [diff] [blame] | 2080 | return NOTIFY_OK; |
Paul Jackson | 4c4d50f | 2006-08-27 01:23:51 -0700 | [diff] [blame] | 2081 | } |
Paul Jackson | 4c4d50f | 2006-08-27 01:23:51 -0700 | [diff] [blame] | 2082 | |
Paul Jackson | b1aac8b | 2006-09-29 02:01:17 -0700 | [diff] [blame] | 2083 | #ifdef CONFIG_MEMORY_HOTPLUG |
Paul Jackson | 38837fc | 2006-09-29 02:01:16 -0700 | [diff] [blame] | 2084 | /* |
Christoph Lameter | 0e1e7c7 | 2007-10-16 01:25:38 -0700 | [diff] [blame] | 2085 | * Keep top_cpuset.mems_allowed tracking node_states[N_HIGH_MEMORY]. |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 2086 | * Call this routine anytime after node_states[N_HIGH_MEMORY] changes. |
| 2087 | * See also the previous routine cpuset_track_online_cpus(). |
Paul Jackson | 38837fc | 2006-09-29 02:01:16 -0700 | [diff] [blame] | 2088 | */ |
Miao Xie | f481891 | 2008-11-19 15:36:30 -0800 | [diff] [blame] | 2089 | static int cpuset_track_online_nodes(struct notifier_block *self, |
| 2090 | unsigned long action, void *arg) |
Paul Jackson | 38837fc | 2006-09-29 02:01:16 -0700 | [diff] [blame] | 2091 | { |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 2092 | cgroup_lock(); |
Miao Xie | f481891 | 2008-11-19 15:36:30 -0800 | [diff] [blame] | 2093 | switch (action) { |
| 2094 | case MEM_ONLINE: |
| 2095 | top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY]; |
| 2096 | break; |
| 2097 | case MEM_OFFLINE: |
| 2098 | top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY]; |
| 2099 | scan_for_empty_cpusets(&top_cpuset); |
| 2100 | break; |
| 2101 | default: |
| 2102 | break; |
| 2103 | } |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 2104 | cgroup_unlock(); |
Miao Xie | f481891 | 2008-11-19 15:36:30 -0800 | [diff] [blame] | 2105 | return NOTIFY_OK; |
Paul Jackson | 38837fc | 2006-09-29 02:01:16 -0700 | [diff] [blame] | 2106 | } |
| 2107 | #endif |
| 2108 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2109 | /** |
| 2110 | * cpuset_init_smp - initialize cpus_allowed |
| 2111 | * |
| 2112 | * Description: Finish top cpuset after cpu, node maps are initialized |
| 2113 | **/ |
| 2114 | |
| 2115 | void __init cpuset_init_smp(void) |
| 2116 | { |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 2117 | cpumask_copy(top_cpuset.cpus_allowed, cpu_online_mask); |
Christoph Lameter | 0e1e7c7 | 2007-10-16 01:25:38 -0700 | [diff] [blame] | 2118 | top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY]; |
Paul Jackson | 4c4d50f | 2006-08-27 01:23:51 -0700 | [diff] [blame] | 2119 | |
Max Krasnyansky | cf41714 | 2008-08-11 14:33:53 -0700 | [diff] [blame] | 2120 | hotcpu_notifier(cpuset_track_online_cpus, 0); |
Miao Xie | f481891 | 2008-11-19 15:36:30 -0800 | [diff] [blame] | 2121 | hotplug_memory_notifier(cpuset_track_online_nodes, 10); |
Miao Xie | f90d411 | 2009-01-16 10:24:10 +0800 | [diff] [blame] | 2122 | |
| 2123 | cpuset_wq = create_singlethread_workqueue("cpuset"); |
| 2124 | BUG_ON(!cpuset_wq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2125 | } |
| 2126 | |
| 2127 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2128 | * cpuset_cpus_allowed - return cpus_allowed mask from a tasks cpuset. |
| 2129 | * @tsk: pointer to task_struct from which to obtain cpuset->cpus_allowed. |
Li Zefan | 6af866a | 2009-01-07 18:08:45 -0800 | [diff] [blame] | 2130 | * @pmask: pointer to struct cpumask variable to receive cpus_allowed set. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2131 | * |
Li Zefan | 300ed6c | 2009-01-07 18:08:44 -0800 | [diff] [blame] | 2132 | * Description: Returns the cpumask_var_t cpus_allowed of the cpuset |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2133 | * attached to the specified @tsk. Guaranteed to return some non-empty |
| 2134 | * subset of cpu_online_map, even if this means going outside the |
| 2135 | * tasks cpuset. |
| 2136 | **/ |
| 2137 | |
Li Zefan | 6af866a | 2009-01-07 18:08:45 -0800 | [diff] [blame] | 2138 | void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2139 | { |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 2140 | mutex_lock(&callback_mutex); |
Mike Travis | f9a86fc | 2008-04-04 18:11:07 -0700 | [diff] [blame] | 2141 | cpuset_cpus_allowed_locked(tsk, pmask); |
Cliff Wickman | 470fd64 | 2007-10-18 23:40:46 -0700 | [diff] [blame] | 2142 | mutex_unlock(&callback_mutex); |
Cliff Wickman | 470fd64 | 2007-10-18 23:40:46 -0700 | [diff] [blame] | 2143 | } |
| 2144 | |
| 2145 | /** |
| 2146 | * cpuset_cpus_allowed_locked - return cpus_allowed mask from a tasks cpuset. |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 2147 | * Must be called with callback_mutex held. |
Cliff Wickman | 470fd64 | 2007-10-18 23:40:46 -0700 | [diff] [blame] | 2148 | **/ |
Li Zefan | 6af866a | 2009-01-07 18:08:45 -0800 | [diff] [blame] | 2149 | void cpuset_cpus_allowed_locked(struct task_struct *tsk, struct cpumask *pmask) |
Cliff Wickman | 470fd64 | 2007-10-18 23:40:46 -0700 | [diff] [blame] | 2150 | { |
Paul Jackson | 909d75a | 2006-01-08 01:01:55 -0800 | [diff] [blame] | 2151 | task_lock(tsk); |
Mike Travis | f9a86fc | 2008-04-04 18:11:07 -0700 | [diff] [blame] | 2152 | guarantee_online_cpus(task_cs(tsk), pmask); |
Paul Jackson | 909d75a | 2006-01-08 01:01:55 -0800 | [diff] [blame] | 2153 | task_unlock(tsk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2154 | } |
| 2155 | |
| 2156 | void cpuset_init_current_mems_allowed(void) |
| 2157 | { |
Mike Travis | f9a86fc | 2008-04-04 18:11:07 -0700 | [diff] [blame] | 2158 | nodes_setall(current->mems_allowed); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2159 | } |
| 2160 | |
Randy Dunlap | d9fd8a6 | 2005-07-27 11:45:11 -0700 | [diff] [blame] | 2161 | /** |
Paul Jackson | 909d75a | 2006-01-08 01:01:55 -0800 | [diff] [blame] | 2162 | * cpuset_mems_allowed - return mems_allowed mask from a tasks cpuset. |
| 2163 | * @tsk: pointer to task_struct from which to obtain cpuset->mems_allowed. |
| 2164 | * |
| 2165 | * Description: Returns the nodemask_t mems_allowed of the cpuset |
| 2166 | * attached to the specified @tsk. Guaranteed to return some non-empty |
Christoph Lameter | 0e1e7c7 | 2007-10-16 01:25:38 -0700 | [diff] [blame] | 2167 | * subset of node_states[N_HIGH_MEMORY], even if this means going outside the |
Paul Jackson | 909d75a | 2006-01-08 01:01:55 -0800 | [diff] [blame] | 2168 | * tasks cpuset. |
| 2169 | **/ |
| 2170 | |
| 2171 | nodemask_t cpuset_mems_allowed(struct task_struct *tsk) |
| 2172 | { |
| 2173 | nodemask_t mask; |
| 2174 | |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 2175 | mutex_lock(&callback_mutex); |
Paul Jackson | 909d75a | 2006-01-08 01:01:55 -0800 | [diff] [blame] | 2176 | task_lock(tsk); |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 2177 | guarantee_online_mems(task_cs(tsk), &mask); |
Paul Jackson | 909d75a | 2006-01-08 01:01:55 -0800 | [diff] [blame] | 2178 | task_unlock(tsk); |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 2179 | mutex_unlock(&callback_mutex); |
Paul Jackson | 909d75a | 2006-01-08 01:01:55 -0800 | [diff] [blame] | 2180 | |
| 2181 | return mask; |
| 2182 | } |
| 2183 | |
| 2184 | /** |
Mel Gorman | 19770b3 | 2008-04-28 02:12:18 -0700 | [diff] [blame] | 2185 | * cpuset_nodemask_valid_mems_allowed - check nodemask vs. curremt mems_allowed |
| 2186 | * @nodemask: the nodemask to be checked |
Randy Dunlap | d9fd8a6 | 2005-07-27 11:45:11 -0700 | [diff] [blame] | 2187 | * |
Mel Gorman | 19770b3 | 2008-04-28 02:12:18 -0700 | [diff] [blame] | 2188 | * Are any of the nodes in the nodemask allowed in current->mems_allowed? |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2189 | */ |
Mel Gorman | 19770b3 | 2008-04-28 02:12:18 -0700 | [diff] [blame] | 2190 | int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2191 | { |
Mel Gorman | 19770b3 | 2008-04-28 02:12:18 -0700 | [diff] [blame] | 2192 | return nodes_intersects(*nodemask, current->mems_allowed); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2193 | } |
| 2194 | |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2195 | /* |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 2196 | * nearest_hardwall_ancestor() - Returns the nearest mem_exclusive or |
| 2197 | * mem_hardwall ancestor to the specified cpuset. Call holding |
| 2198 | * callback_mutex. If no ancestor is mem_exclusive or mem_hardwall |
| 2199 | * (an unusual configuration), then returns the root cpuset. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2200 | */ |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 2201 | static const struct cpuset *nearest_hardwall_ancestor(const struct cpuset *cs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2202 | { |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 2203 | while (!(is_mem_exclusive(cs) || is_mem_hardwall(cs)) && cs->parent) |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2204 | cs = cs->parent; |
| 2205 | return cs; |
| 2206 | } |
| 2207 | |
| 2208 | /** |
Paul Jackson | 02a0e53 | 2006-12-13 00:34:25 -0800 | [diff] [blame] | 2209 | * cpuset_zone_allowed_softwall - Can we allocate on zone z's memory node? |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2210 | * @z: is this zone on an allowed node? |
Paul Jackson | 02a0e53 | 2006-12-13 00:34:25 -0800 | [diff] [blame] | 2211 | * @gfp_mask: memory allocation flags |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2212 | * |
Paul Jackson | 02a0e53 | 2006-12-13 00:34:25 -0800 | [diff] [blame] | 2213 | * If we're in interrupt, yes, we can always allocate. If |
| 2214 | * __GFP_THISNODE is set, yes, we can always allocate. If zone |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2215 | * z's node is in our tasks mems_allowed, yes. If it's not a |
| 2216 | * __GFP_HARDWALL request and this zone's nodes is in the nearest |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 2217 | * hardwalled cpuset ancestor to this tasks cpuset, yes. |
David Rientjes | c596d9f | 2007-05-06 14:49:32 -0700 | [diff] [blame] | 2218 | * If the task has been OOM killed and has access to memory reserves |
| 2219 | * as specified by the TIF_MEMDIE flag, yes. |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2220 | * Otherwise, no. |
| 2221 | * |
Paul Jackson | 02a0e53 | 2006-12-13 00:34:25 -0800 | [diff] [blame] | 2222 | * If __GFP_HARDWALL is set, cpuset_zone_allowed_softwall() |
| 2223 | * reduces to cpuset_zone_allowed_hardwall(). Otherwise, |
| 2224 | * cpuset_zone_allowed_softwall() might sleep, and might allow a zone |
| 2225 | * from an enclosing cpuset. |
| 2226 | * |
| 2227 | * cpuset_zone_allowed_hardwall() only handles the simpler case of |
| 2228 | * hardwall cpusets, and never sleeps. |
| 2229 | * |
| 2230 | * The __GFP_THISNODE placement logic is really handled elsewhere, |
| 2231 | * by forcibly using a zonelist starting at a specified node, and by |
| 2232 | * (in get_page_from_freelist()) refusing to consider the zones for |
| 2233 | * any node on the zonelist except the first. By the time any such |
| 2234 | * calls get to this routine, we should just shut up and say 'yes'. |
| 2235 | * |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2236 | * GFP_USER allocations are marked with the __GFP_HARDWALL bit, |
David Rientjes | c596d9f | 2007-05-06 14:49:32 -0700 | [diff] [blame] | 2237 | * and do not allow allocations outside the current tasks cpuset |
| 2238 | * unless the task has been OOM killed as is marked TIF_MEMDIE. |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2239 | * GFP_KERNEL allocations are not so marked, so can escape to the |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 2240 | * nearest enclosing hardwalled ancestor cpuset. |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2241 | * |
Paul Jackson | 02a0e53 | 2006-12-13 00:34:25 -0800 | [diff] [blame] | 2242 | * Scanning up parent cpusets requires callback_mutex. The |
| 2243 | * __alloc_pages() routine only calls here with __GFP_HARDWALL bit |
| 2244 | * _not_ set if it's a GFP_KERNEL allocation, and all nodes in the |
| 2245 | * current tasks mems_allowed came up empty on the first pass over |
| 2246 | * the zonelist. So only GFP_KERNEL allocations, if all nodes in the |
| 2247 | * cpuset are short of memory, might require taking the callback_mutex |
| 2248 | * mutex. |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2249 | * |
Paul Jackson | 36be57f | 2006-05-20 15:00:10 -0700 | [diff] [blame] | 2250 | * The first call here from mm/page_alloc:get_page_from_freelist() |
Paul Jackson | 02a0e53 | 2006-12-13 00:34:25 -0800 | [diff] [blame] | 2251 | * has __GFP_HARDWALL set in gfp_mask, enforcing hardwall cpusets, |
| 2252 | * so no allocation on a node outside the cpuset is allowed (unless |
| 2253 | * in interrupt, of course). |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2254 | * |
Paul Jackson | 36be57f | 2006-05-20 15:00:10 -0700 | [diff] [blame] | 2255 | * The second pass through get_page_from_freelist() doesn't even call |
| 2256 | * here for GFP_ATOMIC calls. For those calls, the __alloc_pages() |
| 2257 | * variable 'wait' is not set, and the bit ALLOC_CPUSET is not set |
| 2258 | * in alloc_flags. That logic and the checks below have the combined |
| 2259 | * affect that: |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2260 | * in_interrupt - any node ok (current task context irrelevant) |
| 2261 | * GFP_ATOMIC - any node ok |
David Rientjes | c596d9f | 2007-05-06 14:49:32 -0700 | [diff] [blame] | 2262 | * TIF_MEMDIE - any node ok |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 2263 | * GFP_KERNEL - any node in enclosing hardwalled cpuset ok |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2264 | * GFP_USER - only nodes in current tasks mems allowed ok. |
Paul Jackson | 36be57f | 2006-05-20 15:00:10 -0700 | [diff] [blame] | 2265 | * |
| 2266 | * Rule: |
Paul Jackson | 02a0e53 | 2006-12-13 00:34:25 -0800 | [diff] [blame] | 2267 | * Don't call cpuset_zone_allowed_softwall if you can't sleep, unless you |
Paul Jackson | 36be57f | 2006-05-20 15:00:10 -0700 | [diff] [blame] | 2268 | * pass in the __GFP_HARDWALL flag set in gfp_flag, which disables |
| 2269 | * the code that might scan up ancestor cpusets and sleep. |
Paul Jackson | 02a0e53 | 2006-12-13 00:34:25 -0800 | [diff] [blame] | 2270 | */ |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2271 | |
Paul Jackson | 02a0e53 | 2006-12-13 00:34:25 -0800 | [diff] [blame] | 2272 | int __cpuset_zone_allowed_softwall(struct zone *z, gfp_t gfp_mask) |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2273 | { |
| 2274 | int node; /* node that zone z is on */ |
| 2275 | const struct cpuset *cs; /* current cpuset ancestors */ |
Paul Jackson | 29afd49 | 2006-03-24 03:16:12 -0800 | [diff] [blame] | 2276 | int allowed; /* is allocation in zone z allowed? */ |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2277 | |
Christoph Lameter | 9b819d2 | 2006-09-25 23:31:40 -0700 | [diff] [blame] | 2278 | if (in_interrupt() || (gfp_mask & __GFP_THISNODE)) |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2279 | return 1; |
Christoph Lameter | 89fa302 | 2006-09-25 23:31:55 -0700 | [diff] [blame] | 2280 | node = zone_to_nid(z); |
Paul Jackson | 92d1dbd | 2006-05-20 15:00:11 -0700 | [diff] [blame] | 2281 | might_sleep_if(!(gfp_mask & __GFP_HARDWALL)); |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2282 | if (node_isset(node, current->mems_allowed)) |
| 2283 | return 1; |
David Rientjes | c596d9f | 2007-05-06 14:49:32 -0700 | [diff] [blame] | 2284 | /* |
| 2285 | * Allow tasks that have access to memory reserves because they have |
| 2286 | * been OOM killed to get memory anywhere. |
| 2287 | */ |
| 2288 | if (unlikely(test_thread_flag(TIF_MEMDIE))) |
| 2289 | return 1; |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2290 | if (gfp_mask & __GFP_HARDWALL) /* If hardwall request, stop here */ |
| 2291 | return 0; |
| 2292 | |
Bob Picco | 5563e77 | 2005-11-13 16:06:35 -0800 | [diff] [blame] | 2293 | if (current->flags & PF_EXITING) /* Let dying task have memory */ |
| 2294 | return 1; |
| 2295 | |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2296 | /* Not hardwall and node outside mems_allowed: scan up cpusets */ |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 2297 | mutex_lock(&callback_mutex); |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 2298 | |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 2299 | task_lock(current); |
Paul Menage | 7860836 | 2008-04-29 01:00:26 -0700 | [diff] [blame] | 2300 | cs = nearest_hardwall_ancestor(task_cs(current)); |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 2301 | task_unlock(current); |
| 2302 | |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2303 | allowed = node_isset(node, cs->mems_allowed); |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 2304 | mutex_unlock(&callback_mutex); |
Paul Jackson | 9bf2229 | 2005-09-06 15:18:12 -0700 | [diff] [blame] | 2305 | return allowed; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2306 | } |
| 2307 | |
Paul Jackson | 02a0e53 | 2006-12-13 00:34:25 -0800 | [diff] [blame] | 2308 | /* |
| 2309 | * cpuset_zone_allowed_hardwall - Can we allocate on zone z's memory node? |
| 2310 | * @z: is this zone on an allowed node? |
| 2311 | * @gfp_mask: memory allocation flags |
| 2312 | * |
| 2313 | * If we're in interrupt, yes, we can always allocate. |
| 2314 | * If __GFP_THISNODE is set, yes, we can always allocate. If zone |
David Rientjes | c596d9f | 2007-05-06 14:49:32 -0700 | [diff] [blame] | 2315 | * z's node is in our tasks mems_allowed, yes. If the task has been |
| 2316 | * OOM killed and has access to memory reserves as specified by the |
| 2317 | * TIF_MEMDIE flag, yes. Otherwise, no. |
Paul Jackson | 02a0e53 | 2006-12-13 00:34:25 -0800 | [diff] [blame] | 2318 | * |
| 2319 | * The __GFP_THISNODE placement logic is really handled elsewhere, |
| 2320 | * by forcibly using a zonelist starting at a specified node, and by |
| 2321 | * (in get_page_from_freelist()) refusing to consider the zones for |
| 2322 | * any node on the zonelist except the first. By the time any such |
| 2323 | * calls get to this routine, we should just shut up and say 'yes'. |
| 2324 | * |
| 2325 | * Unlike the cpuset_zone_allowed_softwall() variant, above, |
| 2326 | * this variant requires that the zone be in the current tasks |
| 2327 | * mems_allowed or that we're in interrupt. It does not scan up the |
| 2328 | * cpuset hierarchy for the nearest enclosing mem_exclusive cpuset. |
| 2329 | * It never sleeps. |
| 2330 | */ |
| 2331 | |
| 2332 | int __cpuset_zone_allowed_hardwall(struct zone *z, gfp_t gfp_mask) |
| 2333 | { |
| 2334 | int node; /* node that zone z is on */ |
| 2335 | |
| 2336 | if (in_interrupt() || (gfp_mask & __GFP_THISNODE)) |
| 2337 | return 1; |
| 2338 | node = zone_to_nid(z); |
| 2339 | if (node_isset(node, current->mems_allowed)) |
| 2340 | return 1; |
Daniel Walker | dedf8b7 | 2007-10-18 03:06:04 -0700 | [diff] [blame] | 2341 | /* |
| 2342 | * Allow tasks that have access to memory reserves because they have |
| 2343 | * been OOM killed to get memory anywhere. |
| 2344 | */ |
| 2345 | if (unlikely(test_thread_flag(TIF_MEMDIE))) |
| 2346 | return 1; |
Paul Jackson | 02a0e53 | 2006-12-13 00:34:25 -0800 | [diff] [blame] | 2347 | return 0; |
| 2348 | } |
| 2349 | |
Paul Jackson | ef08e3b | 2005-09-06 15:18:13 -0700 | [diff] [blame] | 2350 | /** |
Paul Jackson | 505970b | 2006-01-14 13:21:06 -0800 | [diff] [blame] | 2351 | * cpuset_lock - lock out any changes to cpuset structures |
| 2352 | * |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 2353 | * The out of memory (oom) code needs to mutex_lock cpusets |
Paul Jackson | 505970b | 2006-01-14 13:21:06 -0800 | [diff] [blame] | 2354 | * from being changed while it scans the tasklist looking for a |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 2355 | * task in an overlapping cpuset. Expose callback_mutex via this |
Paul Jackson | 505970b | 2006-01-14 13:21:06 -0800 | [diff] [blame] | 2356 | * cpuset_lock() routine, so the oom code can lock it, before |
| 2357 | * locking the task list. The tasklist_lock is a spinlock, so |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 2358 | * must be taken inside callback_mutex. |
Paul Jackson | 505970b | 2006-01-14 13:21:06 -0800 | [diff] [blame] | 2359 | */ |
| 2360 | |
| 2361 | void cpuset_lock(void) |
| 2362 | { |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 2363 | mutex_lock(&callback_mutex); |
Paul Jackson | 505970b | 2006-01-14 13:21:06 -0800 | [diff] [blame] | 2364 | } |
| 2365 | |
| 2366 | /** |
| 2367 | * cpuset_unlock - release lock on cpuset changes |
| 2368 | * |
| 2369 | * Undo the lock taken in a previous cpuset_lock() call. |
| 2370 | */ |
| 2371 | |
| 2372 | void cpuset_unlock(void) |
| 2373 | { |
Ingo Molnar | 3d3f26a | 2006-03-23 03:00:18 -0800 | [diff] [blame] | 2374 | mutex_unlock(&callback_mutex); |
Paul Jackson | 505970b | 2006-01-14 13:21:06 -0800 | [diff] [blame] | 2375 | } |
| 2376 | |
| 2377 | /** |
Paul Jackson | 825a46a | 2006-03-24 03:16:03 -0800 | [diff] [blame] | 2378 | * cpuset_mem_spread_node() - On which node to begin search for a page |
| 2379 | * |
| 2380 | * If a task is marked PF_SPREAD_PAGE or PF_SPREAD_SLAB (as for |
| 2381 | * tasks in a cpuset with is_spread_page or is_spread_slab set), |
| 2382 | * and if the memory allocation used cpuset_mem_spread_node() |
| 2383 | * to determine on which node to start looking, as it will for |
| 2384 | * certain page cache or slab cache pages such as used for file |
| 2385 | * system buffers and inode caches, then instead of starting on the |
| 2386 | * local node to look for a free page, rather spread the starting |
| 2387 | * node around the tasks mems_allowed nodes. |
| 2388 | * |
| 2389 | * We don't have to worry about the returned node being offline |
| 2390 | * because "it can't happen", and even if it did, it would be ok. |
| 2391 | * |
| 2392 | * The routines calling guarantee_online_mems() are careful to |
| 2393 | * only set nodes in task->mems_allowed that are online. So it |
| 2394 | * should not be possible for the following code to return an |
| 2395 | * offline node. But if it did, that would be ok, as this routine |
| 2396 | * is not returning the node where the allocation must be, only |
| 2397 | * the node where the search should start. The zonelist passed to |
| 2398 | * __alloc_pages() will include all nodes. If the slab allocator |
| 2399 | * is passed an offline node, it will fall back to the local node. |
| 2400 | * See kmem_cache_alloc_node(). |
| 2401 | */ |
| 2402 | |
| 2403 | int cpuset_mem_spread_node(void) |
| 2404 | { |
| 2405 | int node; |
| 2406 | |
| 2407 | node = next_node(current->cpuset_mem_spread_rotor, current->mems_allowed); |
| 2408 | if (node == MAX_NUMNODES) |
| 2409 | node = first_node(current->mems_allowed); |
| 2410 | current->cpuset_mem_spread_rotor = node; |
| 2411 | return node; |
| 2412 | } |
| 2413 | EXPORT_SYMBOL_GPL(cpuset_mem_spread_node); |
| 2414 | |
| 2415 | /** |
David Rientjes | bbe373f | 2007-10-16 23:25:58 -0700 | [diff] [blame] | 2416 | * cpuset_mems_allowed_intersects - Does @tsk1's mems_allowed intersect @tsk2's? |
| 2417 | * @tsk1: pointer to task_struct of some task. |
| 2418 | * @tsk2: pointer to task_struct of some other task. |
Paul Jackson | ef08e3b | 2005-09-06 15:18:13 -0700 | [diff] [blame] | 2419 | * |
David Rientjes | bbe373f | 2007-10-16 23:25:58 -0700 | [diff] [blame] | 2420 | * Description: Return true if @tsk1's mems_allowed intersects the |
| 2421 | * mems_allowed of @tsk2. Used by the OOM killer to determine if |
| 2422 | * one of the task's memory usage might impact the memory available |
| 2423 | * to the other. |
Paul Jackson | ef08e3b | 2005-09-06 15:18:13 -0700 | [diff] [blame] | 2424 | **/ |
| 2425 | |
David Rientjes | bbe373f | 2007-10-16 23:25:58 -0700 | [diff] [blame] | 2426 | int cpuset_mems_allowed_intersects(const struct task_struct *tsk1, |
| 2427 | const struct task_struct *tsk2) |
Paul Jackson | ef08e3b | 2005-09-06 15:18:13 -0700 | [diff] [blame] | 2428 | { |
David Rientjes | bbe373f | 2007-10-16 23:25:58 -0700 | [diff] [blame] | 2429 | return nodes_intersects(tsk1->mems_allowed, tsk2->mems_allowed); |
Paul Jackson | ef08e3b | 2005-09-06 15:18:13 -0700 | [diff] [blame] | 2430 | } |
| 2431 | |
David Rientjes | 75aa199 | 2009-01-06 14:39:01 -0800 | [diff] [blame] | 2432 | /** |
| 2433 | * cpuset_print_task_mems_allowed - prints task's cpuset and mems_allowed |
| 2434 | * @task: pointer to task_struct of some task. |
| 2435 | * |
| 2436 | * Description: Prints @task's name, cpuset name, and cached copy of its |
| 2437 | * mems_allowed to the kernel log. Must hold task_lock(task) to allow |
| 2438 | * dereferencing task_cs(task). |
| 2439 | */ |
| 2440 | void cpuset_print_task_mems_allowed(struct task_struct *tsk) |
| 2441 | { |
| 2442 | struct dentry *dentry; |
| 2443 | |
| 2444 | dentry = task_cs(tsk)->css.cgroup->dentry; |
| 2445 | spin_lock(&cpuset_buffer_lock); |
| 2446 | snprintf(cpuset_name, CPUSET_NAME_LEN, |
| 2447 | dentry ? (const char *)dentry->d_name.name : "/"); |
| 2448 | nodelist_scnprintf(cpuset_nodelist, CPUSET_NODELIST_LEN, |
| 2449 | tsk->mems_allowed); |
| 2450 | printk(KERN_INFO "%s cpuset=%s mems_allowed=%s\n", |
| 2451 | tsk->comm, cpuset_name, cpuset_nodelist); |
| 2452 | spin_unlock(&cpuset_buffer_lock); |
| 2453 | } |
| 2454 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2455 | /* |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 2456 | * Collection of memory_pressure is suppressed unless |
| 2457 | * this flag is enabled by writing "1" to the special |
| 2458 | * cpuset file 'memory_pressure_enabled' in the root cpuset. |
| 2459 | */ |
| 2460 | |
Paul Jackson | c5b2aff | 2006-01-08 01:01:51 -0800 | [diff] [blame] | 2461 | int cpuset_memory_pressure_enabled __read_mostly; |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 2462 | |
| 2463 | /** |
| 2464 | * cpuset_memory_pressure_bump - keep stats of per-cpuset reclaims. |
| 2465 | * |
| 2466 | * Keep a running average of the rate of synchronous (direct) |
| 2467 | * page reclaim efforts initiated by tasks in each cpuset. |
| 2468 | * |
| 2469 | * This represents the rate at which some task in the cpuset |
| 2470 | * ran low on memory on all nodes it was allowed to use, and |
| 2471 | * had to enter the kernels page reclaim code in an effort to |
| 2472 | * create more free memory by tossing clean pages or swapping |
| 2473 | * or writing dirty pages. |
| 2474 | * |
| 2475 | * Display to user space in the per-cpuset read-only file |
| 2476 | * "memory_pressure". Value displayed is an integer |
| 2477 | * representing the recent rate of entry into the synchronous |
| 2478 | * (direct) page reclaim by any task attached to the cpuset. |
| 2479 | **/ |
| 2480 | |
| 2481 | void __cpuset_memory_pressure_bump(void) |
| 2482 | { |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 2483 | task_lock(current); |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 2484 | fmeter_markevent(&task_cs(current)->fmeter); |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 2485 | task_unlock(current); |
| 2486 | } |
| 2487 | |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 2488 | #ifdef CONFIG_PROC_PID_CPUSET |
Paul Jackson | 3e0d98b | 2006-01-08 01:01:49 -0800 | [diff] [blame] | 2489 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2490 | * proc_cpuset_show() |
| 2491 | * - Print tasks cpuset path into seq_file. |
| 2492 | * - Used for /proc/<pid>/cpuset. |
Paul Jackson | 053199e | 2005-10-30 15:02:30 -0800 | [diff] [blame] | 2493 | * - No need to task_lock(tsk) on this tsk->cpuset reference, as it |
| 2494 | * doesn't really matter if tsk->cpuset changes after we read it, |
Paul Jackson | c8d9c90 | 2008-02-07 00:14:46 -0800 | [diff] [blame] | 2495 | * and we take cgroup_mutex, keeping cpuset_attach() from changing it |
Paul Menage | 2df167a | 2008-02-07 00:14:45 -0800 | [diff] [blame] | 2496 | * anyway. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2497 | */ |
Paul Jackson | 029190c | 2007-10-18 23:40:20 -0700 | [diff] [blame] | 2498 | static int proc_cpuset_show(struct seq_file *m, void *unused_v) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2499 | { |
Eric W. Biederman | 13b41b0 | 2006-06-26 00:25:56 -0700 | [diff] [blame] | 2500 | struct pid *pid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2501 | struct task_struct *tsk; |
| 2502 | char *buf; |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 2503 | struct cgroup_subsys_state *css; |
Eric W. Biederman | 99f8955 | 2006-06-26 00:25:55 -0700 | [diff] [blame] | 2504 | int retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2505 | |
Eric W. Biederman | 99f8955 | 2006-06-26 00:25:55 -0700 | [diff] [blame] | 2506 | retval = -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2507 | buf = kmalloc(PAGE_SIZE, GFP_KERNEL); |
| 2508 | if (!buf) |
Eric W. Biederman | 99f8955 | 2006-06-26 00:25:55 -0700 | [diff] [blame] | 2509 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2510 | |
Eric W. Biederman | 99f8955 | 2006-06-26 00:25:55 -0700 | [diff] [blame] | 2511 | retval = -ESRCH; |
Eric W. Biederman | 13b41b0 | 2006-06-26 00:25:56 -0700 | [diff] [blame] | 2512 | pid = m->private; |
| 2513 | tsk = get_pid_task(pid, PIDTYPE_PID); |
Eric W. Biederman | 99f8955 | 2006-06-26 00:25:55 -0700 | [diff] [blame] | 2514 | if (!tsk) |
| 2515 | goto out_free; |
| 2516 | |
| 2517 | retval = -EINVAL; |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 2518 | cgroup_lock(); |
| 2519 | css = task_subsys_state(tsk, cpuset_subsys_id); |
| 2520 | retval = cgroup_path(css->cgroup, buf, PAGE_SIZE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2521 | if (retval < 0) |
Eric W. Biederman | 99f8955 | 2006-06-26 00:25:55 -0700 | [diff] [blame] | 2522 | goto out_unlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2523 | seq_puts(m, buf); |
| 2524 | seq_putc(m, '\n'); |
Eric W. Biederman | 99f8955 | 2006-06-26 00:25:55 -0700 | [diff] [blame] | 2525 | out_unlock: |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 2526 | cgroup_unlock(); |
Eric W. Biederman | 99f8955 | 2006-06-26 00:25:55 -0700 | [diff] [blame] | 2527 | put_task_struct(tsk); |
| 2528 | out_free: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2529 | kfree(buf); |
Eric W. Biederman | 99f8955 | 2006-06-26 00:25:55 -0700 | [diff] [blame] | 2530 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2531 | return retval; |
| 2532 | } |
| 2533 | |
| 2534 | static int cpuset_open(struct inode *inode, struct file *file) |
| 2535 | { |
Eric W. Biederman | 13b41b0 | 2006-06-26 00:25:56 -0700 | [diff] [blame] | 2536 | struct pid *pid = PROC_I(inode)->pid; |
| 2537 | return single_open(file, proc_cpuset_show, pid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2538 | } |
| 2539 | |
Arjan van de Ven | 9a32144 | 2007-02-12 00:55:35 -0800 | [diff] [blame] | 2540 | const struct file_operations proc_cpuset_operations = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2541 | .open = cpuset_open, |
| 2542 | .read = seq_read, |
| 2543 | .llseek = seq_lseek, |
| 2544 | .release = single_release, |
| 2545 | }; |
Paul Menage | 8793d85 | 2007-10-18 23:39:39 -0700 | [diff] [blame] | 2546 | #endif /* CONFIG_PROC_PID_CPUSET */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2547 | |
| 2548 | /* Display task cpus_allowed, mems_allowed in /proc/<pid>/status file. */ |
Eric W. Biederman | df5f831 | 2008-02-08 04:18:33 -0800 | [diff] [blame] | 2549 | void cpuset_task_status_allowed(struct seq_file *m, struct task_struct *task) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2550 | { |
Eric W. Biederman | df5f831 | 2008-02-08 04:18:33 -0800 | [diff] [blame] | 2551 | seq_printf(m, "Cpus_allowed:\t"); |
Lai Jiangshan | 30e8e13 | 2008-10-18 20:28:20 -0700 | [diff] [blame] | 2552 | seq_cpumask(m, &task->cpus_allowed); |
Eric W. Biederman | df5f831 | 2008-02-08 04:18:33 -0800 | [diff] [blame] | 2553 | seq_printf(m, "\n"); |
Mike Travis | 39106dc | 2008-04-08 11:43:03 -0700 | [diff] [blame] | 2554 | seq_printf(m, "Cpus_allowed_list:\t"); |
Lai Jiangshan | 30e8e13 | 2008-10-18 20:28:20 -0700 | [diff] [blame] | 2555 | seq_cpumask_list(m, &task->cpus_allowed); |
Mike Travis | 39106dc | 2008-04-08 11:43:03 -0700 | [diff] [blame] | 2556 | seq_printf(m, "\n"); |
Eric W. Biederman | df5f831 | 2008-02-08 04:18:33 -0800 | [diff] [blame] | 2557 | seq_printf(m, "Mems_allowed:\t"); |
Lai Jiangshan | 30e8e13 | 2008-10-18 20:28:20 -0700 | [diff] [blame] | 2558 | seq_nodemask(m, &task->mems_allowed); |
Eric W. Biederman | df5f831 | 2008-02-08 04:18:33 -0800 | [diff] [blame] | 2559 | seq_printf(m, "\n"); |
Mike Travis | 39106dc | 2008-04-08 11:43:03 -0700 | [diff] [blame] | 2560 | seq_printf(m, "Mems_allowed_list:\t"); |
Lai Jiangshan | 30e8e13 | 2008-10-18 20:28:20 -0700 | [diff] [blame] | 2561 | seq_nodemask_list(m, &task->mems_allowed); |
Mike Travis | 39106dc | 2008-04-08 11:43:03 -0700 | [diff] [blame] | 2562 | seq_printf(m, "\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2563 | } |