Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* CPU control. |
| 2 | * (C) 2001, 2002, 2003, 2004 Rusty Russell |
| 3 | * |
| 4 | * This code is licenced under the GPL. |
| 5 | */ |
| 6 | #include <linux/proc_fs.h> |
| 7 | #include <linux/smp.h> |
| 8 | #include <linux/init.h> |
| 9 | #include <linux/notifier.h> |
| 10 | #include <linux/sched.h> |
| 11 | #include <linux/unistd.h> |
| 12 | #include <linux/cpu.h> |
Anton Vorontsov | cb79295 | 2012-05-31 16:26:22 -0700 | [diff] [blame] | 13 | #include <linux/oom.h> |
| 14 | #include <linux/rcupdate.h> |
Paul Gortmaker | 9984de1 | 2011-05-23 14:51:41 -0400 | [diff] [blame] | 15 | #include <linux/export.h> |
Anton Vorontsov | e4cc2f8 | 2012-05-31 16:26:26 -0700 | [diff] [blame] | 16 | #include <linux/bug.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 17 | #include <linux/kthread.h> |
| 18 | #include <linux/stop_machine.h> |
Ingo Molnar | 81615b6 | 2006-06-26 00:24:32 -0700 | [diff] [blame] | 19 | #include <linux/mutex.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 20 | #include <linux/gfp.h> |
Srivatsa S. Bhat | 79cfbdf | 2011-11-03 00:59:25 +0100 | [diff] [blame] | 21 | #include <linux/suspend.h> |
Gautham R. Shenoy | a19423b | 2014-03-11 02:04:03 +0530 | [diff] [blame] | 22 | #include <linux/lockdep.h> |
Preeti U Murthy | 345527b | 2015-03-30 14:59:19 +0530 | [diff] [blame] | 23 | #include <linux/tick.h> |
Thomas Gleixner | a899418 | 2015-07-05 17:12:30 +0000 | [diff] [blame] | 24 | #include <linux/irq.h> |
Todd E Brandt | bb3632c | 2014-06-06 05:40:17 -0700 | [diff] [blame] | 25 | #include <trace/events/power.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | |
Thomas Gleixner | 38498a6 | 2012-04-20 13:05:44 +0000 | [diff] [blame] | 27 | #include "smpboot.h" |
| 28 | |
Rusty Russell | 98a79d6 | 2008-12-13 21:19:41 +1030 | [diff] [blame] | 29 | #ifdef CONFIG_SMP |
Rusty Russell | b3199c0 | 2008-12-30 09:05:14 +1030 | [diff] [blame] | 30 | /* Serializes the updates to cpu_online_mask, cpu_present_mask */ |
Linus Torvalds | aa95387 | 2006-07-23 12:12:16 -0700 | [diff] [blame] | 31 | static DEFINE_MUTEX(cpu_add_remove_lock); |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 32 | bool cpuhp_tasks_frozen; |
| 33 | EXPORT_SYMBOL_GPL(cpuhp_tasks_frozen); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | |
Lai Jiangshan | 79a6cde | 2010-05-26 14:43:36 -0700 | [diff] [blame] | 35 | /* |
Srivatsa S. Bhat | 93ae4f9 | 2014-03-11 02:04:14 +0530 | [diff] [blame] | 36 | * The following two APIs (cpu_maps_update_begin/done) must be used when |
| 37 | * attempting to serialize the updates to cpu_online_mask & cpu_present_mask. |
| 38 | * The APIs cpu_notifier_register_begin/done() must be used to protect CPU |
| 39 | * hotplug callback (un)registration performed using __register_cpu_notifier() |
| 40 | * or __unregister_cpu_notifier(). |
Lai Jiangshan | 79a6cde | 2010-05-26 14:43:36 -0700 | [diff] [blame] | 41 | */ |
| 42 | void cpu_maps_update_begin(void) |
| 43 | { |
| 44 | mutex_lock(&cpu_add_remove_lock); |
| 45 | } |
Srivatsa S. Bhat | 93ae4f9 | 2014-03-11 02:04:14 +0530 | [diff] [blame] | 46 | EXPORT_SYMBOL(cpu_notifier_register_begin); |
Lai Jiangshan | 79a6cde | 2010-05-26 14:43:36 -0700 | [diff] [blame] | 47 | |
| 48 | void cpu_maps_update_done(void) |
| 49 | { |
| 50 | mutex_unlock(&cpu_add_remove_lock); |
| 51 | } |
Srivatsa S. Bhat | 93ae4f9 | 2014-03-11 02:04:14 +0530 | [diff] [blame] | 52 | EXPORT_SYMBOL(cpu_notifier_register_done); |
Lai Jiangshan | 79a6cde | 2010-05-26 14:43:36 -0700 | [diff] [blame] | 53 | |
Daniel J Blueman | 5c113fb | 2010-06-01 12:15:11 +0100 | [diff] [blame] | 54 | static RAW_NOTIFIER_HEAD(cpu_chain); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 56 | /* If set, cpu_up and cpu_down will return -EBUSY and do nothing. |
| 57 | * Should always be manipulated under cpu_add_remove_lock |
| 58 | */ |
| 59 | static int cpu_hotplug_disabled; |
| 60 | |
Lai Jiangshan | 79a6cde | 2010-05-26 14:43:36 -0700 | [diff] [blame] | 61 | #ifdef CONFIG_HOTPLUG_CPU |
| 62 | |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 63 | static struct { |
| 64 | struct task_struct *active_writer; |
David Hildenbrand | 87af9e7 | 2014-12-12 10:11:44 +0100 | [diff] [blame] | 65 | /* wait queue to wake up the active_writer */ |
| 66 | wait_queue_head_t wq; |
| 67 | /* verifies that no writer will get active while readers are active */ |
| 68 | struct mutex lock; |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 69 | /* |
| 70 | * Also blocks the new readers during |
| 71 | * an ongoing cpu hotplug operation. |
| 72 | */ |
David Hildenbrand | 87af9e7 | 2014-12-12 10:11:44 +0100 | [diff] [blame] | 73 | atomic_t refcount; |
Gautham R. Shenoy | a19423b | 2014-03-11 02:04:03 +0530 | [diff] [blame] | 74 | |
| 75 | #ifdef CONFIG_DEBUG_LOCK_ALLOC |
| 76 | struct lockdep_map dep_map; |
| 77 | #endif |
Linus Torvalds | 31950eb | 2009-06-22 21:18:12 -0700 | [diff] [blame] | 78 | } cpu_hotplug = { |
| 79 | .active_writer = NULL, |
David Hildenbrand | 87af9e7 | 2014-12-12 10:11:44 +0100 | [diff] [blame] | 80 | .wq = __WAIT_QUEUE_HEAD_INITIALIZER(cpu_hotplug.wq), |
Linus Torvalds | 31950eb | 2009-06-22 21:18:12 -0700 | [diff] [blame] | 81 | .lock = __MUTEX_INITIALIZER(cpu_hotplug.lock), |
Gautham R. Shenoy | a19423b | 2014-03-11 02:04:03 +0530 | [diff] [blame] | 82 | #ifdef CONFIG_DEBUG_LOCK_ALLOC |
| 83 | .dep_map = {.name = "cpu_hotplug.lock" }, |
| 84 | #endif |
Linus Torvalds | 31950eb | 2009-06-22 21:18:12 -0700 | [diff] [blame] | 85 | }; |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 86 | |
Gautham R. Shenoy | a19423b | 2014-03-11 02:04:03 +0530 | [diff] [blame] | 87 | /* Lockdep annotations for get/put_online_cpus() and cpu_hotplug_begin/end() */ |
| 88 | #define cpuhp_lock_acquire_read() lock_map_acquire_read(&cpu_hotplug.dep_map) |
Paul E. McKenney | dd56af4 | 2014-08-25 20:25:06 -0700 | [diff] [blame] | 89 | #define cpuhp_lock_acquire_tryread() \ |
| 90 | lock_map_acquire_tryread(&cpu_hotplug.dep_map) |
Gautham R. Shenoy | a19423b | 2014-03-11 02:04:03 +0530 | [diff] [blame] | 91 | #define cpuhp_lock_acquire() lock_map_acquire(&cpu_hotplug.dep_map) |
| 92 | #define cpuhp_lock_release() lock_map_release(&cpu_hotplug.dep_map) |
| 93 | |
Paul E. McKenney | 62db99f | 2014-10-22 14:51:49 -0700 | [diff] [blame] | 94 | |
Gautham R Shenoy | 86ef5c9 | 2008-01-25 21:08:02 +0100 | [diff] [blame] | 95 | void get_online_cpus(void) |
Ashok Raj | a9d9baa | 2005-11-28 13:43:46 -0800 | [diff] [blame] | 96 | { |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 97 | might_sleep(); |
| 98 | if (cpu_hotplug.active_writer == current) |
Linus Torvalds | aa95387 | 2006-07-23 12:12:16 -0700 | [diff] [blame] | 99 | return; |
Gautham R. Shenoy | a19423b | 2014-03-11 02:04:03 +0530 | [diff] [blame] | 100 | cpuhp_lock_acquire_read(); |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 101 | mutex_lock(&cpu_hotplug.lock); |
David Hildenbrand | 87af9e7 | 2014-12-12 10:11:44 +0100 | [diff] [blame] | 102 | atomic_inc(&cpu_hotplug.refcount); |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 103 | mutex_unlock(&cpu_hotplug.lock); |
Ashok Raj | a9d9baa | 2005-11-28 13:43:46 -0800 | [diff] [blame] | 104 | } |
Gautham R Shenoy | 86ef5c9 | 2008-01-25 21:08:02 +0100 | [diff] [blame] | 105 | EXPORT_SYMBOL_GPL(get_online_cpus); |
Ashok Raj | 90d45d1 | 2005-11-08 21:34:24 -0800 | [diff] [blame] | 106 | |
Gautham R Shenoy | 86ef5c9 | 2008-01-25 21:08:02 +0100 | [diff] [blame] | 107 | void put_online_cpus(void) |
Ashok Raj | a9d9baa | 2005-11-28 13:43:46 -0800 | [diff] [blame] | 108 | { |
David Hildenbrand | 87af9e7 | 2014-12-12 10:11:44 +0100 | [diff] [blame] | 109 | int refcount; |
| 110 | |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 111 | if (cpu_hotplug.active_writer == current) |
Linus Torvalds | aa95387 | 2006-07-23 12:12:16 -0700 | [diff] [blame] | 112 | return; |
Srivatsa S. Bhat | 075663d | 2012-10-08 16:28:20 -0700 | [diff] [blame] | 113 | |
David Hildenbrand | 87af9e7 | 2014-12-12 10:11:44 +0100 | [diff] [blame] | 114 | refcount = atomic_dec_return(&cpu_hotplug.refcount); |
| 115 | if (WARN_ON(refcount < 0)) /* try to fix things up */ |
| 116 | atomic_inc(&cpu_hotplug.refcount); |
Srivatsa S. Bhat | 075663d | 2012-10-08 16:28:20 -0700 | [diff] [blame] | 117 | |
David Hildenbrand | 87af9e7 | 2014-12-12 10:11:44 +0100 | [diff] [blame] | 118 | if (refcount <= 0 && waitqueue_active(&cpu_hotplug.wq)) |
| 119 | wake_up(&cpu_hotplug.wq); |
| 120 | |
Gautham R. Shenoy | a19423b | 2014-03-11 02:04:03 +0530 | [diff] [blame] | 121 | cpuhp_lock_release(); |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 122 | |
Ashok Raj | a9d9baa | 2005-11-28 13:43:46 -0800 | [diff] [blame] | 123 | } |
Gautham R Shenoy | 86ef5c9 | 2008-01-25 21:08:02 +0100 | [diff] [blame] | 124 | EXPORT_SYMBOL_GPL(put_online_cpus); |
Ashok Raj | a9d9baa | 2005-11-28 13:43:46 -0800 | [diff] [blame] | 125 | |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 126 | /* |
| 127 | * This ensures that the hotplug operation can begin only when the |
| 128 | * refcount goes to zero. |
| 129 | * |
| 130 | * Note that during a cpu-hotplug operation, the new readers, if any, |
| 131 | * will be blocked by the cpu_hotplug.lock |
| 132 | * |
Oleg Nesterov | d2ba7e2 | 2008-04-29 01:00:29 -0700 | [diff] [blame] | 133 | * Since cpu_hotplug_begin() is always called after invoking |
| 134 | * cpu_maps_update_begin(), we can be sure that only one writer is active. |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 135 | * |
| 136 | * Note that theoretically, there is a possibility of a livelock: |
| 137 | * - Refcount goes to zero, last reader wakes up the sleeping |
| 138 | * writer. |
| 139 | * - Last reader unlocks the cpu_hotplug.lock. |
| 140 | * - A new reader arrives at this moment, bumps up the refcount. |
| 141 | * - The writer acquires the cpu_hotplug.lock finds the refcount |
| 142 | * non zero and goes to sleep again. |
| 143 | * |
| 144 | * However, this is very difficult to achieve in practice since |
Gautham R Shenoy | 86ef5c9 | 2008-01-25 21:08:02 +0100 | [diff] [blame] | 145 | * get_online_cpus() not an api which is called all that often. |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 146 | * |
| 147 | */ |
Toshi Kani | b9d10be | 2013-08-12 09:45:53 -0600 | [diff] [blame] | 148 | void cpu_hotplug_begin(void) |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 149 | { |
David Hildenbrand | 87af9e7 | 2014-12-12 10:11:44 +0100 | [diff] [blame] | 150 | DEFINE_WAIT(wait); |
Oleg Nesterov | d2ba7e2 | 2008-04-29 01:00:29 -0700 | [diff] [blame] | 151 | |
David Hildenbrand | 87af9e7 | 2014-12-12 10:11:44 +0100 | [diff] [blame] | 152 | cpu_hotplug.active_writer = current; |
Gautham R. Shenoy | a19423b | 2014-03-11 02:04:03 +0530 | [diff] [blame] | 153 | cpuhp_lock_acquire(); |
David Hildenbrand | 87af9e7 | 2014-12-12 10:11:44 +0100 | [diff] [blame] | 154 | |
Oleg Nesterov | d2ba7e2 | 2008-04-29 01:00:29 -0700 | [diff] [blame] | 155 | for (;;) { |
| 156 | mutex_lock(&cpu_hotplug.lock); |
David Hildenbrand | 87af9e7 | 2014-12-12 10:11:44 +0100 | [diff] [blame] | 157 | prepare_to_wait(&cpu_hotplug.wq, &wait, TASK_UNINTERRUPTIBLE); |
| 158 | if (likely(!atomic_read(&cpu_hotplug.refcount))) |
| 159 | break; |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 160 | mutex_unlock(&cpu_hotplug.lock); |
| 161 | schedule(); |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 162 | } |
David Hildenbrand | 87af9e7 | 2014-12-12 10:11:44 +0100 | [diff] [blame] | 163 | finish_wait(&cpu_hotplug.wq, &wait); |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 164 | } |
| 165 | |
Toshi Kani | b9d10be | 2013-08-12 09:45:53 -0600 | [diff] [blame] | 166 | void cpu_hotplug_done(void) |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 167 | { |
| 168 | cpu_hotplug.active_writer = NULL; |
| 169 | mutex_unlock(&cpu_hotplug.lock); |
Gautham R. Shenoy | a19423b | 2014-03-11 02:04:03 +0530 | [diff] [blame] | 170 | cpuhp_lock_release(); |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 171 | } |
Lai Jiangshan | 79a6cde | 2010-05-26 14:43:36 -0700 | [diff] [blame] | 172 | |
Srivatsa S. Bhat | 16e53db | 2013-06-12 14:04:36 -0700 | [diff] [blame] | 173 | /* |
| 174 | * Wait for currently running CPU hotplug operations to complete (if any) and |
| 175 | * disable future CPU hotplug (from sysfs). The 'cpu_add_remove_lock' protects |
| 176 | * the 'cpu_hotplug_disabled' flag. The same lock is also acquired by the |
| 177 | * hotplug path before performing hotplug operations. So acquiring that lock |
| 178 | * guarantees mutual exclusion from any currently running hotplug operations. |
| 179 | */ |
| 180 | void cpu_hotplug_disable(void) |
| 181 | { |
| 182 | cpu_maps_update_begin(); |
Vitaly Kuznetsov | 89af7ba | 2015-08-05 00:52:46 -0700 | [diff] [blame] | 183 | cpu_hotplug_disabled++; |
Srivatsa S. Bhat | 16e53db | 2013-06-12 14:04:36 -0700 | [diff] [blame] | 184 | cpu_maps_update_done(); |
| 185 | } |
Vitaly Kuznetsov | 32145c4 | 2015-08-05 00:52:47 -0700 | [diff] [blame] | 186 | EXPORT_SYMBOL_GPL(cpu_hotplug_disable); |
Srivatsa S. Bhat | 16e53db | 2013-06-12 14:04:36 -0700 | [diff] [blame] | 187 | |
| 188 | void cpu_hotplug_enable(void) |
| 189 | { |
| 190 | cpu_maps_update_begin(); |
Vitaly Kuznetsov | 89af7ba | 2015-08-05 00:52:46 -0700 | [diff] [blame] | 191 | WARN_ON(--cpu_hotplug_disabled < 0); |
Srivatsa S. Bhat | 16e53db | 2013-06-12 14:04:36 -0700 | [diff] [blame] | 192 | cpu_maps_update_done(); |
| 193 | } |
Vitaly Kuznetsov | 32145c4 | 2015-08-05 00:52:47 -0700 | [diff] [blame] | 194 | EXPORT_SYMBOL_GPL(cpu_hotplug_enable); |
Toshi Kani | b9d10be | 2013-08-12 09:45:53 -0600 | [diff] [blame] | 195 | #endif /* CONFIG_HOTPLUG_CPU */ |
Lai Jiangshan | 79a6cde | 2010-05-26 14:43:36 -0700 | [diff] [blame] | 196 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 197 | /* Need to know about CPUs going up/down? */ |
Mathias Krause | 71cf5ae | 2015-07-19 20:06:22 +0200 | [diff] [blame] | 198 | int register_cpu_notifier(struct notifier_block *nb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 199 | { |
Neil Brown | bd5349c | 2006-10-17 00:10:35 -0700 | [diff] [blame] | 200 | int ret; |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 201 | cpu_maps_update_begin(); |
Neil Brown | bd5349c | 2006-10-17 00:10:35 -0700 | [diff] [blame] | 202 | ret = raw_notifier_chain_register(&cpu_chain, nb); |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 203 | cpu_maps_update_done(); |
Neil Brown | bd5349c | 2006-10-17 00:10:35 -0700 | [diff] [blame] | 204 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | } |
Chandra Seetharaman | 65edc68 | 2006-06-27 02:54:08 -0700 | [diff] [blame] | 206 | |
Mathias Krause | 71cf5ae | 2015-07-19 20:06:22 +0200 | [diff] [blame] | 207 | int __register_cpu_notifier(struct notifier_block *nb) |
Srivatsa S. Bhat | 93ae4f9 | 2014-03-11 02:04:14 +0530 | [diff] [blame] | 208 | { |
| 209 | return raw_notifier_chain_register(&cpu_chain, nb); |
| 210 | } |
| 211 | |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 212 | static int __cpu_notify(unsigned long val, unsigned int cpu, int nr_to_call, |
Akinobu Mita | e9fb763 | 2010-05-26 14:43:28 -0700 | [diff] [blame] | 213 | int *nr_calls) |
| 214 | { |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 215 | unsigned long mod = cpuhp_tasks_frozen ? CPU_TASKS_FROZEN : 0; |
| 216 | void *hcpu = (void *)(long)cpu; |
| 217 | |
Akinobu Mita | e6bde73 | 2010-05-26 14:43:29 -0700 | [diff] [blame] | 218 | int ret; |
| 219 | |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 220 | ret = __raw_notifier_call_chain(&cpu_chain, val | mod, hcpu, nr_to_call, |
Akinobu Mita | e9fb763 | 2010-05-26 14:43:28 -0700 | [diff] [blame] | 221 | nr_calls); |
Akinobu Mita | e6bde73 | 2010-05-26 14:43:29 -0700 | [diff] [blame] | 222 | |
| 223 | return notifier_to_errno(ret); |
Akinobu Mita | e9fb763 | 2010-05-26 14:43:28 -0700 | [diff] [blame] | 224 | } |
| 225 | |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 226 | static int cpu_notify(unsigned long val, unsigned int cpu) |
Akinobu Mita | e9fb763 | 2010-05-26 14:43:28 -0700 | [diff] [blame] | 227 | { |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 228 | return __cpu_notify(val, cpu, -1, NULL); |
Akinobu Mita | e9fb763 | 2010-05-26 14:43:28 -0700 | [diff] [blame] | 229 | } |
| 230 | |
Linus Torvalds | 00b9b0a | 2010-05-27 10:32:08 -0700 | [diff] [blame] | 231 | #ifdef CONFIG_HOTPLUG_CPU |
| 232 | |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 233 | static void cpu_notify_nofail(unsigned long val, unsigned int cpu) |
Akinobu Mita | e9fb763 | 2010-05-26 14:43:28 -0700 | [diff] [blame] | 234 | { |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 235 | BUG_ON(cpu_notify(val, cpu)); |
Akinobu Mita | e9fb763 | 2010-05-26 14:43:28 -0700 | [diff] [blame] | 236 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | EXPORT_SYMBOL(register_cpu_notifier); |
Srivatsa S. Bhat | 93ae4f9 | 2014-03-11 02:04:14 +0530 | [diff] [blame] | 238 | EXPORT_SYMBOL(__register_cpu_notifier); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | |
Mathias Krause | 71cf5ae | 2015-07-19 20:06:22 +0200 | [diff] [blame] | 240 | void unregister_cpu_notifier(struct notifier_block *nb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | { |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 242 | cpu_maps_update_begin(); |
Neil Brown | bd5349c | 2006-10-17 00:10:35 -0700 | [diff] [blame] | 243 | raw_notifier_chain_unregister(&cpu_chain, nb); |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 244 | cpu_maps_update_done(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 245 | } |
| 246 | EXPORT_SYMBOL(unregister_cpu_notifier); |
| 247 | |
Mathias Krause | 71cf5ae | 2015-07-19 20:06:22 +0200 | [diff] [blame] | 248 | void __unregister_cpu_notifier(struct notifier_block *nb) |
Srivatsa S. Bhat | 93ae4f9 | 2014-03-11 02:04:14 +0530 | [diff] [blame] | 249 | { |
| 250 | raw_notifier_chain_unregister(&cpu_chain, nb); |
| 251 | } |
| 252 | EXPORT_SYMBOL(__unregister_cpu_notifier); |
| 253 | |
Anton Vorontsov | e4cc2f8 | 2012-05-31 16:26:26 -0700 | [diff] [blame] | 254 | /** |
| 255 | * clear_tasks_mm_cpumask - Safely clear tasks' mm_cpumask for a CPU |
| 256 | * @cpu: a CPU id |
| 257 | * |
| 258 | * This function walks all processes, finds a valid mm struct for each one and |
| 259 | * then clears a corresponding bit in mm's cpumask. While this all sounds |
| 260 | * trivial, there are various non-obvious corner cases, which this function |
| 261 | * tries to solve in a safe manner. |
| 262 | * |
| 263 | * Also note that the function uses a somewhat relaxed locking scheme, so it may |
| 264 | * be called only for an already offlined CPU. |
| 265 | */ |
Anton Vorontsov | cb79295 | 2012-05-31 16:26:22 -0700 | [diff] [blame] | 266 | void clear_tasks_mm_cpumask(int cpu) |
| 267 | { |
| 268 | struct task_struct *p; |
| 269 | |
| 270 | /* |
| 271 | * This function is called after the cpu is taken down and marked |
| 272 | * offline, so its not like new tasks will ever get this cpu set in |
| 273 | * their mm mask. -- Peter Zijlstra |
| 274 | * Thus, we may use rcu_read_lock() here, instead of grabbing |
| 275 | * full-fledged tasklist_lock. |
| 276 | */ |
Anton Vorontsov | e4cc2f8 | 2012-05-31 16:26:26 -0700 | [diff] [blame] | 277 | WARN_ON(cpu_online(cpu)); |
Anton Vorontsov | cb79295 | 2012-05-31 16:26:22 -0700 | [diff] [blame] | 278 | rcu_read_lock(); |
| 279 | for_each_process(p) { |
| 280 | struct task_struct *t; |
| 281 | |
Anton Vorontsov | e4cc2f8 | 2012-05-31 16:26:26 -0700 | [diff] [blame] | 282 | /* |
| 283 | * Main thread might exit, but other threads may still have |
| 284 | * a valid mm. Find one. |
| 285 | */ |
Anton Vorontsov | cb79295 | 2012-05-31 16:26:22 -0700 | [diff] [blame] | 286 | t = find_lock_task_mm(p); |
| 287 | if (!t) |
| 288 | continue; |
| 289 | cpumask_clear_cpu(cpu, mm_cpumask(t->mm)); |
| 290 | task_unlock(t); |
| 291 | } |
| 292 | rcu_read_unlock(); |
| 293 | } |
| 294 | |
Kirill Tkhai | b728ca0 | 2014-06-25 12:19:55 +0400 | [diff] [blame] | 295 | static inline void check_for_tasks(int dead_cpu) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | { |
Kirill Tkhai | b728ca0 | 2014-06-25 12:19:55 +0400 | [diff] [blame] | 297 | struct task_struct *g, *p; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | |
Oleg Nesterov | a75a606 | 2015-09-10 15:07:50 +0200 | [diff] [blame] | 299 | read_lock(&tasklist_lock); |
| 300 | for_each_process_thread(g, p) { |
Kirill Tkhai | b728ca0 | 2014-06-25 12:19:55 +0400 | [diff] [blame] | 301 | if (!p->on_rq) |
| 302 | continue; |
| 303 | /* |
| 304 | * We do the check with unlocked task_rq(p)->lock. |
| 305 | * Order the reading to do not warn about a task, |
| 306 | * which was running on this cpu in the past, and |
| 307 | * it's just been woken on another cpu. |
| 308 | */ |
| 309 | rmb(); |
| 310 | if (task_cpu(p) != dead_cpu) |
| 311 | continue; |
| 312 | |
| 313 | pr_warn("Task %s (pid=%d) is on cpu %d (state=%ld, flags=%x)\n", |
| 314 | p->comm, task_pid_nr(p), dead_cpu, p->state, p->flags); |
Oleg Nesterov | a75a606 | 2015-09-10 15:07:50 +0200 | [diff] [blame] | 315 | } |
| 316 | read_unlock(&tasklist_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 317 | } |
| 318 | |
| 319 | /* Take this CPU down. */ |
Mathias Krause | 71cf5ae | 2015-07-19 20:06:22 +0200 | [diff] [blame] | 320 | static int take_cpu_down(void *_param) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | { |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 322 | int err, cpu = smp_processor_id(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 323 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 324 | /* Ensure this CPU doesn't handle any more interrupts. */ |
| 325 | err = __cpu_disable(); |
| 326 | if (err < 0) |
Zwane Mwaikambo | f370513 | 2005-06-25 14:54:50 -0700 | [diff] [blame] | 327 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 328 | |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 329 | cpu_notify(CPU_DYING, cpu); |
Thomas Gleixner | 52c063d | 2015-04-03 02:37:24 +0200 | [diff] [blame] | 330 | /* Give up timekeeping duties */ |
| 331 | tick_handover_do_timer(); |
Thomas Gleixner | 14e568e | 2013-01-31 12:11:14 +0000 | [diff] [blame] | 332 | /* Park the stopper thread */ |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 333 | stop_machine_park(cpu); |
Zwane Mwaikambo | f370513 | 2005-06-25 14:54:50 -0700 | [diff] [blame] | 334 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 335 | } |
| 336 | |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 337 | /* Requires cpu_add_remove_lock to be held */ |
Mathias Krause | 71cf5ae | 2015-07-19 20:06:22 +0200 | [diff] [blame] | 338 | static int _cpu_down(unsigned int cpu, int tasks_frozen) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 339 | { |
Heiko Carstens | e7407dc | 2007-05-09 02:34:04 -0700 | [diff] [blame] | 340 | int err, nr_calls = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 341 | |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 342 | if (num_online_cpus() == 1) |
| 343 | return -EBUSY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 344 | |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 345 | if (!cpu_online(cpu)) |
| 346 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 347 | |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 348 | cpu_hotplug_begin(); |
Michael Rodriguez | 4d51985 | 2011-03-22 16:34:07 -0700 | [diff] [blame] | 349 | |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 350 | cpuhp_tasks_frozen = tasks_frozen; |
| 351 | |
| 352 | err = __cpu_notify(CPU_DOWN_PREPARE, cpu, -1, &nr_calls); |
Akinobu Mita | e6bde73 | 2010-05-26 14:43:29 -0700 | [diff] [blame] | 353 | if (err) { |
Akinobu Mita | a0d8cdb | 2007-10-18 03:05:12 -0700 | [diff] [blame] | 354 | nr_calls--; |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 355 | __cpu_notify(CPU_DOWN_FAILED, cpu, nr_calls, NULL); |
Fabian Frederick | 84117da | 2014-06-04 16:11:17 -0700 | [diff] [blame] | 356 | pr_warn("%s: attempt to take down CPU %u failed\n", |
| 357 | __func__, cpu); |
Gautham R Shenoy | baaca49 | 2007-05-09 02:34:03 -0700 | [diff] [blame] | 358 | goto out_release; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 359 | } |
| 360 | |
Peter Zijlstra | 6acce3e | 2013-10-11 14:38:20 +0200 | [diff] [blame] | 361 | /* |
| 362 | * By now we've cleared cpu_active_mask, wait for all preempt-disabled |
| 363 | * and RCU users of this state to go away such that all new such users |
| 364 | * will observe it. |
| 365 | * |
| 366 | * For CONFIG_PREEMPT we have preemptible RCU and its sync_rcu() might |
Paul E. McKenney | 779de6c | 2015-06-10 13:34:41 -0700 | [diff] [blame] | 367 | * not imply sync_sched(), so wait for both. |
Michael wang | 106dd5a | 2013-11-13 11:10:56 +0800 | [diff] [blame] | 368 | * |
| 369 | * Do sync before park smpboot threads to take care the rcu boost case. |
Peter Zijlstra | 6acce3e | 2013-10-11 14:38:20 +0200 | [diff] [blame] | 370 | */ |
Paul E. McKenney | 779de6c | 2015-06-10 13:34:41 -0700 | [diff] [blame] | 371 | if (IS_ENABLED(CONFIG_PREEMPT)) |
| 372 | synchronize_rcu_mult(call_rcu, call_rcu_sched); |
| 373 | else |
| 374 | synchronize_rcu(); |
Peter Zijlstra | 6acce3e | 2013-10-11 14:38:20 +0200 | [diff] [blame] | 375 | |
Michael wang | 106dd5a | 2013-11-13 11:10:56 +0800 | [diff] [blame] | 376 | smpboot_park_threads(cpu); |
| 377 | |
Peter Zijlstra | 6acce3e | 2013-10-11 14:38:20 +0200 | [diff] [blame] | 378 | /* |
Thomas Gleixner | a899418 | 2015-07-05 17:12:30 +0000 | [diff] [blame] | 379 | * Prevent irq alloc/free while the dying cpu reorganizes the |
| 380 | * interrupt affinities. |
| 381 | */ |
| 382 | irq_lock_sparse(); |
| 383 | |
| 384 | /* |
Peter Zijlstra | 6acce3e | 2013-10-11 14:38:20 +0200 | [diff] [blame] | 385 | * So now all preempt/rcu users must observe !cpu_active(). |
| 386 | */ |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 387 | err = stop_machine(take_cpu_down, NULL, cpumask_of(cpu)); |
Rusty Russell | 0432158 | 2008-07-28 12:16:29 -0500 | [diff] [blame] | 388 | if (err) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 389 | /* CPU didn't die: tell everyone. Can't complain. */ |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 390 | cpu_notify_nofail(CPU_DOWN_FAILED, cpu); |
Thomas Gleixner | a899418 | 2015-07-05 17:12:30 +0000 | [diff] [blame] | 391 | irq_unlock_sparse(); |
Oleg Nesterov | 6a1bdc1 | 2010-03-15 10:10:23 +0100 | [diff] [blame] | 392 | goto out_release; |
Satoru Takeuchi | 8fa1d7d | 2006-10-28 10:38:57 -0700 | [diff] [blame] | 393 | } |
Rusty Russell | 0432158 | 2008-07-28 12:16:29 -0500 | [diff] [blame] | 394 | BUG_ON(cpu_online(cpu)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 395 | |
Peter Zijlstra | 48c5cca | 2010-11-13 19:32:29 +0100 | [diff] [blame] | 396 | /* |
| 397 | * The migration_call() CPU_DYING callback will have removed all |
| 398 | * runnable tasks from the cpu, there's only the idle task left now |
| 399 | * that the migration thread is done doing the stop_machine thing. |
Peter Zijlstra | 51a96c7 | 2010-11-19 20:37:53 +0100 | [diff] [blame] | 400 | * |
| 401 | * Wait for the stop thread to go away. |
Peter Zijlstra | 48c5cca | 2010-11-13 19:32:29 +0100 | [diff] [blame] | 402 | */ |
Paul E. McKenney | 528a25b | 2015-01-28 14:09:43 -0800 | [diff] [blame] | 403 | while (!per_cpu(cpu_dead_idle, cpu)) |
Peter Zijlstra | 51a96c7 | 2010-11-19 20:37:53 +0100 | [diff] [blame] | 404 | cpu_relax(); |
Paul E. McKenney | 528a25b | 2015-01-28 14:09:43 -0800 | [diff] [blame] | 405 | smp_mb(); /* Read from cpu_dead_idle before __cpu_die(). */ |
| 406 | per_cpu(cpu_dead_idle, cpu) = false; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 407 | |
Thomas Gleixner | a899418 | 2015-07-05 17:12:30 +0000 | [diff] [blame] | 408 | /* Interrupts are moved away from the dying cpu, reenable alloc/free */ |
| 409 | irq_unlock_sparse(); |
| 410 | |
Preeti U Murthy | 345527b | 2015-03-30 14:59:19 +0530 | [diff] [blame] | 411 | hotplug_cpu__broadcast_tick_pull(cpu); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 412 | /* This actually kills the CPU. */ |
| 413 | __cpu_die(cpu); |
| 414 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 415 | /* CPU is completely dead: tell everyone. Too late to complain. */ |
Thomas Gleixner | a49b116 | 2015-04-03 02:38:05 +0200 | [diff] [blame] | 416 | tick_cleanup_dead_cpu(cpu); |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 417 | cpu_notify_nofail(CPU_DEAD, cpu); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 418 | |
| 419 | check_for_tasks(cpu); |
| 420 | |
Gautham R Shenoy | baaca49 | 2007-05-09 02:34:03 -0700 | [diff] [blame] | 421 | out_release: |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 422 | cpu_hotplug_done(); |
Akinobu Mita | e9fb763 | 2010-05-26 14:43:28 -0700 | [diff] [blame] | 423 | if (!err) |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 424 | cpu_notify_nofail(CPU_POST_DEAD, cpu); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 425 | return err; |
| 426 | } |
| 427 | |
Mathias Krause | 71cf5ae | 2015-07-19 20:06:22 +0200 | [diff] [blame] | 428 | int cpu_down(unsigned int cpu) |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 429 | { |
Heiko Carstens | 9ea09af | 2008-12-22 12:36:30 +0100 | [diff] [blame] | 430 | int err; |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 431 | |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 432 | cpu_maps_update_begin(); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 433 | |
Max Krasnyansky | e761b77 | 2008-07-15 04:43:49 -0700 | [diff] [blame] | 434 | if (cpu_hotplug_disabled) { |
| 435 | err = -EBUSY; |
| 436 | goto out; |
| 437 | } |
| 438 | |
Max Krasnyansky | e761b77 | 2008-07-15 04:43:49 -0700 | [diff] [blame] | 439 | err = _cpu_down(cpu, 0); |
| 440 | |
Max Krasnyansky | e761b77 | 2008-07-15 04:43:49 -0700 | [diff] [blame] | 441 | out: |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 442 | cpu_maps_update_done(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 443 | return err; |
| 444 | } |
Zhang Rui | b62b8ef | 2008-04-29 02:35:56 -0400 | [diff] [blame] | 445 | EXPORT_SYMBOL(cpu_down); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 446 | #endif /*CONFIG_HOTPLUG_CPU*/ |
| 447 | |
Paul E. McKenney | 00df35f | 2015-04-12 08:06:55 -0700 | [diff] [blame] | 448 | /* |
| 449 | * Unpark per-CPU smpboot kthreads at CPU-online time. |
| 450 | */ |
| 451 | static int smpboot_thread_call(struct notifier_block *nfb, |
| 452 | unsigned long action, void *hcpu) |
| 453 | { |
| 454 | int cpu = (long)hcpu; |
| 455 | |
| 456 | switch (action & ~CPU_TASKS_FROZEN) { |
| 457 | |
Paul E. McKenney | 64eaf974 | 2015-04-15 12:45:41 -0700 | [diff] [blame] | 458 | case CPU_DOWN_FAILED: |
Paul E. McKenney | 00df35f | 2015-04-12 08:06:55 -0700 | [diff] [blame] | 459 | case CPU_ONLINE: |
| 460 | smpboot_unpark_threads(cpu); |
| 461 | break; |
| 462 | |
| 463 | default: |
| 464 | break; |
| 465 | } |
| 466 | |
| 467 | return NOTIFY_OK; |
| 468 | } |
| 469 | |
| 470 | static struct notifier_block smpboot_thread_notifier = { |
| 471 | .notifier_call = smpboot_thread_call, |
| 472 | .priority = CPU_PRI_SMPBOOT, |
| 473 | }; |
| 474 | |
Paul Gortmaker | 927da9d | 2015-04-27 18:47:58 -0400 | [diff] [blame] | 475 | void smpboot_thread_init(void) |
Paul E. McKenney | 00df35f | 2015-04-12 08:06:55 -0700 | [diff] [blame] | 476 | { |
| 477 | register_cpu_notifier(&smpboot_thread_notifier); |
| 478 | } |
| 479 | |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 480 | /* Requires cpu_add_remove_lock to be held */ |
Paul Gortmaker | 0db0628 | 2013-06-19 14:53:51 -0400 | [diff] [blame] | 481 | static int _cpu_up(unsigned int cpu, int tasks_frozen) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 482 | { |
Suresh Siddha | 3bb5d2e | 2012-04-20 17:08:50 -0700 | [diff] [blame] | 483 | struct task_struct *idle; |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 484 | int ret, nr_calls = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 485 | |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 486 | cpu_hotplug_begin(); |
Thomas Gleixner | 38498a6 | 2012-04-20 13:05:44 +0000 | [diff] [blame] | 487 | |
Yasuaki Ishimatsu | 5e5041f | 2012-10-23 01:30:54 +0200 | [diff] [blame] | 488 | if (cpu_online(cpu) || !cpu_present(cpu)) { |
| 489 | ret = -EINVAL; |
| 490 | goto out; |
| 491 | } |
| 492 | |
Suresh Siddha | 3bb5d2e | 2012-04-20 17:08:50 -0700 | [diff] [blame] | 493 | idle = idle_thread_get(cpu); |
| 494 | if (IS_ERR(idle)) { |
| 495 | ret = PTR_ERR(idle); |
Thomas Gleixner | 38498a6 | 2012-04-20 13:05:44 +0000 | [diff] [blame] | 496 | goto out; |
Suresh Siddha | 3bb5d2e | 2012-04-20 17:08:50 -0700 | [diff] [blame] | 497 | } |
Thomas Gleixner | 38498a6 | 2012-04-20 13:05:44 +0000 | [diff] [blame] | 498 | |
Thomas Gleixner | f97f8f0 | 2012-07-16 10:42:36 +0000 | [diff] [blame] | 499 | ret = smpboot_create_threads(cpu); |
| 500 | if (ret) |
| 501 | goto out; |
| 502 | |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 503 | cpuhp_tasks_frozen = tasks_frozen; |
| 504 | |
| 505 | ret = __cpu_notify(CPU_UP_PREPARE, cpu, -1, &nr_calls); |
Akinobu Mita | e6bde73 | 2010-05-26 14:43:29 -0700 | [diff] [blame] | 506 | if (ret) { |
Akinobu Mita | a0d8cdb | 2007-10-18 03:05:12 -0700 | [diff] [blame] | 507 | nr_calls--; |
Fabian Frederick | 84117da | 2014-06-04 16:11:17 -0700 | [diff] [blame] | 508 | pr_warn("%s: attempt to bring up CPU %u failed\n", |
| 509 | __func__, cpu); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 510 | goto out_notify; |
| 511 | } |
| 512 | |
| 513 | /* Arch-specific enabling code. */ |
Suresh Siddha | 3bb5d2e | 2012-04-20 17:08:50 -0700 | [diff] [blame] | 514 | ret = __cpu_up(cpu, idle); |
Thomas Gleixner | a899418 | 2015-07-05 17:12:30 +0000 | [diff] [blame] | 515 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 516 | if (ret != 0) |
| 517 | goto out_notify; |
Eric Sesterhenn | 6978c70 | 2006-03-24 18:45:21 +0100 | [diff] [blame] | 518 | BUG_ON(!cpu_online(cpu)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 519 | |
| 520 | /* Now call notifier in preparation. */ |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 521 | cpu_notify(CPU_ONLINE, cpu); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 522 | |
| 523 | out_notify: |
| 524 | if (ret != 0) |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 525 | __cpu_notify(CPU_UP_CANCELED, cpu, nr_calls, NULL); |
Thomas Gleixner | 38498a6 | 2012-04-20 13:05:44 +0000 | [diff] [blame] | 526 | out: |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 527 | cpu_hotplug_done(); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 528 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 529 | return ret; |
| 530 | } |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 531 | |
Paul Gortmaker | 0db0628 | 2013-06-19 14:53:51 -0400 | [diff] [blame] | 532 | int cpu_up(unsigned int cpu) |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 533 | { |
| 534 | int err = 0; |
minskey guo | cf23422 | 2010-05-24 14:32:41 -0700 | [diff] [blame] | 535 | |
Rusty Russell | e0b582e | 2009-01-01 10:12:28 +1030 | [diff] [blame] | 536 | if (!cpu_possible(cpu)) { |
Fabian Frederick | 84117da | 2014-06-04 16:11:17 -0700 | [diff] [blame] | 537 | pr_err("can't online cpu %d because it is not configured as may-hotadd at boot time\n", |
| 538 | cpu); |
Chen Gong | 87d5e02 | 2010-03-05 13:42:38 -0800 | [diff] [blame] | 539 | #if defined(CONFIG_IA64) |
Fabian Frederick | 84117da | 2014-06-04 16:11:17 -0700 | [diff] [blame] | 540 | pr_err("please check additional_cpus= boot parameter\n"); |
KAMEZAWA Hiroyuki | 73e753a | 2007-10-18 23:40:47 -0700 | [diff] [blame] | 541 | #endif |
| 542 | return -EINVAL; |
| 543 | } |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 544 | |
Toshi Kani | 01b0f19 | 2013-11-12 15:07:25 -0800 | [diff] [blame] | 545 | err = try_online_node(cpu_to_node(cpu)); |
| 546 | if (err) |
| 547 | return err; |
minskey guo | cf23422 | 2010-05-24 14:32:41 -0700 | [diff] [blame] | 548 | |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 549 | cpu_maps_update_begin(); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 550 | |
Max Krasnyansky | e761b77 | 2008-07-15 04:43:49 -0700 | [diff] [blame] | 551 | if (cpu_hotplug_disabled) { |
| 552 | err = -EBUSY; |
| 553 | goto out; |
| 554 | } |
| 555 | |
| 556 | err = _cpu_up(cpu, 0); |
| 557 | |
Max Krasnyansky | e761b77 | 2008-07-15 04:43:49 -0700 | [diff] [blame] | 558 | out: |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 559 | cpu_maps_update_done(); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 560 | return err; |
| 561 | } |
Paul E. McKenney | a513f6b | 2011-12-11 21:54:45 -0800 | [diff] [blame] | 562 | EXPORT_SYMBOL_GPL(cpu_up); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 563 | |
Rafael J. Wysocki | f3de4be | 2007-08-30 23:56:29 -0700 | [diff] [blame] | 564 | #ifdef CONFIG_PM_SLEEP_SMP |
Rusty Russell | e0b582e | 2009-01-01 10:12:28 +1030 | [diff] [blame] | 565 | static cpumask_var_t frozen_cpus; |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 566 | |
| 567 | int disable_nonboot_cpus(void) |
| 568 | { |
Rafael J. Wysocki | e9a5f42 | 2010-05-27 22:16:22 +0200 | [diff] [blame] | 569 | int cpu, first_cpu, error = 0; |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 570 | |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 571 | cpu_maps_update_begin(); |
Rusty Russell | e0b582e | 2009-01-01 10:12:28 +1030 | [diff] [blame] | 572 | first_cpu = cpumask_first(cpu_online_mask); |
Xiaotian Feng | 9ee349a | 2009-12-16 18:04:32 +0100 | [diff] [blame] | 573 | /* |
| 574 | * We take down all of the non-boot CPUs in one shot to avoid races |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 575 | * with the userspace trying to use the CPU hotplug at the same time |
| 576 | */ |
Rusty Russell | e0b582e | 2009-01-01 10:12:28 +1030 | [diff] [blame] | 577 | cpumask_clear(frozen_cpus); |
Peter Zijlstra | 6ad4c18 | 2009-11-25 13:31:39 +0100 | [diff] [blame] | 578 | |
Fabian Frederick | 84117da | 2014-06-04 16:11:17 -0700 | [diff] [blame] | 579 | pr_info("Disabling non-boot CPUs ...\n"); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 580 | for_each_online_cpu(cpu) { |
| 581 | if (cpu == first_cpu) |
| 582 | continue; |
Todd E Brandt | bb3632c | 2014-06-06 05:40:17 -0700 | [diff] [blame] | 583 | trace_suspend_resume(TPS("CPU_OFF"), cpu, true); |
Rafael J. Wysocki | 8bb7844 | 2007-05-09 02:35:10 -0700 | [diff] [blame] | 584 | error = _cpu_down(cpu, 1); |
Todd E Brandt | bb3632c | 2014-06-06 05:40:17 -0700 | [diff] [blame] | 585 | trace_suspend_resume(TPS("CPU_OFF"), cpu, false); |
Mike Travis | feae320 | 2009-11-17 18:22:13 -0600 | [diff] [blame] | 586 | if (!error) |
Rusty Russell | e0b582e | 2009-01-01 10:12:28 +1030 | [diff] [blame] | 587 | cpumask_set_cpu(cpu, frozen_cpus); |
Mike Travis | feae320 | 2009-11-17 18:22:13 -0600 | [diff] [blame] | 588 | else { |
Fabian Frederick | 84117da | 2014-06-04 16:11:17 -0700 | [diff] [blame] | 589 | pr_err("Error taking CPU%d down: %d\n", cpu, error); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 590 | break; |
| 591 | } |
| 592 | } |
Joseph Cihula | 86886e5 | 2009-06-30 19:31:07 -0700 | [diff] [blame] | 593 | |
Vitaly Kuznetsov | 89af7ba | 2015-08-05 00:52:46 -0700 | [diff] [blame] | 594 | if (!error) |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 595 | BUG_ON(num_online_cpus() > 1); |
Vitaly Kuznetsov | 89af7ba | 2015-08-05 00:52:46 -0700 | [diff] [blame] | 596 | else |
Fabian Frederick | 84117da | 2014-06-04 16:11:17 -0700 | [diff] [blame] | 597 | pr_err("Non-boot CPUs are not disabled\n"); |
Vitaly Kuznetsov | 89af7ba | 2015-08-05 00:52:46 -0700 | [diff] [blame] | 598 | |
| 599 | /* |
| 600 | * Make sure the CPUs won't be enabled by someone else. We need to do |
| 601 | * this even in case of failure as all disable_nonboot_cpus() users are |
| 602 | * supposed to do enable_nonboot_cpus() on the failure path. |
| 603 | */ |
| 604 | cpu_hotplug_disabled++; |
| 605 | |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 606 | cpu_maps_update_done(); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 607 | return error; |
| 608 | } |
| 609 | |
Suresh Siddha | d0af9ee | 2009-08-19 18:05:36 -0700 | [diff] [blame] | 610 | void __weak arch_enable_nonboot_cpus_begin(void) |
| 611 | { |
| 612 | } |
| 613 | |
| 614 | void __weak arch_enable_nonboot_cpus_end(void) |
| 615 | { |
| 616 | } |
| 617 | |
Mathias Krause | 71cf5ae | 2015-07-19 20:06:22 +0200 | [diff] [blame] | 618 | void enable_nonboot_cpus(void) |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 619 | { |
| 620 | int cpu, error; |
| 621 | |
| 622 | /* Allow everyone to use the CPU hotplug again */ |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 623 | cpu_maps_update_begin(); |
Vitaly Kuznetsov | 89af7ba | 2015-08-05 00:52:46 -0700 | [diff] [blame] | 624 | WARN_ON(--cpu_hotplug_disabled < 0); |
Rusty Russell | e0b582e | 2009-01-01 10:12:28 +1030 | [diff] [blame] | 625 | if (cpumask_empty(frozen_cpus)) |
Rafael J. Wysocki | 1d64b9c | 2007-04-01 23:49:49 -0700 | [diff] [blame] | 626 | goto out; |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 627 | |
Fabian Frederick | 84117da | 2014-06-04 16:11:17 -0700 | [diff] [blame] | 628 | pr_info("Enabling non-boot CPUs ...\n"); |
Suresh Siddha | d0af9ee | 2009-08-19 18:05:36 -0700 | [diff] [blame] | 629 | |
| 630 | arch_enable_nonboot_cpus_begin(); |
| 631 | |
Rusty Russell | e0b582e | 2009-01-01 10:12:28 +1030 | [diff] [blame] | 632 | for_each_cpu(cpu, frozen_cpus) { |
Todd E Brandt | bb3632c | 2014-06-06 05:40:17 -0700 | [diff] [blame] | 633 | trace_suspend_resume(TPS("CPU_ON"), cpu, true); |
Rafael J. Wysocki | 8bb7844 | 2007-05-09 02:35:10 -0700 | [diff] [blame] | 634 | error = _cpu_up(cpu, 1); |
Todd E Brandt | bb3632c | 2014-06-06 05:40:17 -0700 | [diff] [blame] | 635 | trace_suspend_resume(TPS("CPU_ON"), cpu, false); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 636 | if (!error) { |
Fabian Frederick | 84117da | 2014-06-04 16:11:17 -0700 | [diff] [blame] | 637 | pr_info("CPU%d is up\n", cpu); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 638 | continue; |
| 639 | } |
Fabian Frederick | 84117da | 2014-06-04 16:11:17 -0700 | [diff] [blame] | 640 | pr_warn("Error taking CPU%d up: %d\n", cpu, error); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 641 | } |
Suresh Siddha | d0af9ee | 2009-08-19 18:05:36 -0700 | [diff] [blame] | 642 | |
| 643 | arch_enable_nonboot_cpus_end(); |
| 644 | |
Rusty Russell | e0b582e | 2009-01-01 10:12:28 +1030 | [diff] [blame] | 645 | cpumask_clear(frozen_cpus); |
Rafael J. Wysocki | 1d64b9c | 2007-04-01 23:49:49 -0700 | [diff] [blame] | 646 | out: |
Gautham R Shenoy | d221938 | 2008-01-25 21:08:01 +0100 | [diff] [blame] | 647 | cpu_maps_update_done(); |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 648 | } |
Rusty Russell | e0b582e | 2009-01-01 10:12:28 +1030 | [diff] [blame] | 649 | |
Fenghua Yu | d7268a3 | 2011-11-15 21:59:31 +0100 | [diff] [blame] | 650 | static int __init alloc_frozen_cpus(void) |
Rusty Russell | e0b582e | 2009-01-01 10:12:28 +1030 | [diff] [blame] | 651 | { |
| 652 | if (!alloc_cpumask_var(&frozen_cpus, GFP_KERNEL|__GFP_ZERO)) |
| 653 | return -ENOMEM; |
| 654 | return 0; |
| 655 | } |
| 656 | core_initcall(alloc_frozen_cpus); |
Srivatsa S. Bhat | 79cfbdf | 2011-11-03 00:59:25 +0100 | [diff] [blame] | 657 | |
| 658 | /* |
Srivatsa S. Bhat | 79cfbdf | 2011-11-03 00:59:25 +0100 | [diff] [blame] | 659 | * When callbacks for CPU hotplug notifications are being executed, we must |
| 660 | * ensure that the state of the system with respect to the tasks being frozen |
| 661 | * or not, as reported by the notification, remains unchanged *throughout the |
| 662 | * duration* of the execution of the callbacks. |
| 663 | * Hence we need to prevent the freezer from racing with regular CPU hotplug. |
| 664 | * |
| 665 | * This synchronization is implemented by mutually excluding regular CPU |
| 666 | * hotplug and Suspend/Hibernate call paths by hooking onto the Suspend/ |
| 667 | * Hibernate notifications. |
| 668 | */ |
| 669 | static int |
| 670 | cpu_hotplug_pm_callback(struct notifier_block *nb, |
| 671 | unsigned long action, void *ptr) |
| 672 | { |
| 673 | switch (action) { |
| 674 | |
| 675 | case PM_SUSPEND_PREPARE: |
| 676 | case PM_HIBERNATION_PREPARE: |
Srivatsa S. Bhat | 16e53db | 2013-06-12 14:04:36 -0700 | [diff] [blame] | 677 | cpu_hotplug_disable(); |
Srivatsa S. Bhat | 79cfbdf | 2011-11-03 00:59:25 +0100 | [diff] [blame] | 678 | break; |
| 679 | |
| 680 | case PM_POST_SUSPEND: |
| 681 | case PM_POST_HIBERNATION: |
Srivatsa S. Bhat | 16e53db | 2013-06-12 14:04:36 -0700 | [diff] [blame] | 682 | cpu_hotplug_enable(); |
Srivatsa S. Bhat | 79cfbdf | 2011-11-03 00:59:25 +0100 | [diff] [blame] | 683 | break; |
| 684 | |
| 685 | default: |
| 686 | return NOTIFY_DONE; |
| 687 | } |
| 688 | |
| 689 | return NOTIFY_OK; |
| 690 | } |
| 691 | |
| 692 | |
Fenghua Yu | d7268a3 | 2011-11-15 21:59:31 +0100 | [diff] [blame] | 693 | static int __init cpu_hotplug_pm_sync_init(void) |
Srivatsa S. Bhat | 79cfbdf | 2011-11-03 00:59:25 +0100 | [diff] [blame] | 694 | { |
Fenghua Yu | 6e32d47 | 2012-11-13 11:32:43 -0800 | [diff] [blame] | 695 | /* |
| 696 | * cpu_hotplug_pm_callback has higher priority than x86 |
| 697 | * bsp_pm_callback which depends on cpu_hotplug_pm_callback |
| 698 | * to disable cpu hotplug to avoid cpu hotplug race. |
| 699 | */ |
Srivatsa S. Bhat | 79cfbdf | 2011-11-03 00:59:25 +0100 | [diff] [blame] | 700 | pm_notifier(cpu_hotplug_pm_callback, 0); |
| 701 | return 0; |
| 702 | } |
| 703 | core_initcall(cpu_hotplug_pm_sync_init); |
| 704 | |
Rafael J. Wysocki | f3de4be | 2007-08-30 23:56:29 -0700 | [diff] [blame] | 705 | #endif /* CONFIG_PM_SLEEP_SMP */ |
Max Krasnyansky | 68f4f1e | 2008-05-29 11:17:02 -0700 | [diff] [blame] | 706 | |
Manfred Spraul | e545a61 | 2008-09-07 16:57:22 +0200 | [diff] [blame] | 707 | /** |
| 708 | * notify_cpu_starting(cpu) - call the CPU_STARTING notifiers |
| 709 | * @cpu: cpu that just started |
| 710 | * |
| 711 | * This function calls the cpu_chain notifiers with CPU_STARTING. |
| 712 | * It must be called by the arch code on the new cpu, before the new cpu |
| 713 | * enables interrupts and before the "boot" cpu returns from __cpu_up(). |
| 714 | */ |
Paul Gortmaker | 0db0628 | 2013-06-19 14:53:51 -0400 | [diff] [blame] | 715 | void notify_cpu_starting(unsigned int cpu) |
Manfred Spraul | e545a61 | 2008-09-07 16:57:22 +0200 | [diff] [blame] | 716 | { |
Thomas Gleixner | 090e77c | 2016-02-26 18:43:23 +0000 | [diff] [blame^] | 717 | cpu_notify(CPU_STARTING, cpu); |
Manfred Spraul | e545a61 | 2008-09-07 16:57:22 +0200 | [diff] [blame] | 718 | } |
| 719 | |
Max Krasnyansky | 68f4f1e | 2008-05-29 11:17:02 -0700 | [diff] [blame] | 720 | #endif /* CONFIG_SMP */ |
Mike Travis | b8d317d | 2008-07-24 18:21:29 -0700 | [diff] [blame] | 721 | |
Linus Torvalds | e56b3bc | 2008-07-28 11:32:33 -0700 | [diff] [blame] | 722 | /* |
| 723 | * cpu_bit_bitmap[] is a special, "compressed" data structure that |
| 724 | * represents all NR_CPUS bits binary values of 1<<nr. |
| 725 | * |
Rusty Russell | e0b582e | 2009-01-01 10:12:28 +1030 | [diff] [blame] | 726 | * It is used by cpumask_of() to get a constant address to a CPU |
Linus Torvalds | e56b3bc | 2008-07-28 11:32:33 -0700 | [diff] [blame] | 727 | * mask value that has a single bit set only. |
| 728 | */ |
Mike Travis | b8d317d | 2008-07-24 18:21:29 -0700 | [diff] [blame] | 729 | |
Linus Torvalds | e56b3bc | 2008-07-28 11:32:33 -0700 | [diff] [blame] | 730 | /* cpu_bit_bitmap[0] is empty - so we can back into it */ |
Michael Rodriguez | 4d51985 | 2011-03-22 16:34:07 -0700 | [diff] [blame] | 731 | #define MASK_DECLARE_1(x) [x+1][0] = (1UL << (x)) |
Linus Torvalds | e56b3bc | 2008-07-28 11:32:33 -0700 | [diff] [blame] | 732 | #define MASK_DECLARE_2(x) MASK_DECLARE_1(x), MASK_DECLARE_1(x+1) |
| 733 | #define MASK_DECLARE_4(x) MASK_DECLARE_2(x), MASK_DECLARE_2(x+2) |
| 734 | #define MASK_DECLARE_8(x) MASK_DECLARE_4(x), MASK_DECLARE_4(x+4) |
Mike Travis | b8d317d | 2008-07-24 18:21:29 -0700 | [diff] [blame] | 735 | |
Linus Torvalds | e56b3bc | 2008-07-28 11:32:33 -0700 | [diff] [blame] | 736 | const unsigned long cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)] = { |
Mike Travis | b8d317d | 2008-07-24 18:21:29 -0700 | [diff] [blame] | 737 | |
Linus Torvalds | e56b3bc | 2008-07-28 11:32:33 -0700 | [diff] [blame] | 738 | MASK_DECLARE_8(0), MASK_DECLARE_8(8), |
| 739 | MASK_DECLARE_8(16), MASK_DECLARE_8(24), |
| 740 | #if BITS_PER_LONG > 32 |
| 741 | MASK_DECLARE_8(32), MASK_DECLARE_8(40), |
| 742 | MASK_DECLARE_8(48), MASK_DECLARE_8(56), |
Mike Travis | b8d317d | 2008-07-24 18:21:29 -0700 | [diff] [blame] | 743 | #endif |
| 744 | }; |
Linus Torvalds | e56b3bc | 2008-07-28 11:32:33 -0700 | [diff] [blame] | 745 | EXPORT_SYMBOL_GPL(cpu_bit_bitmap); |
Rusty Russell | 2d3854a | 2008-11-05 13:39:10 +1100 | [diff] [blame] | 746 | |
| 747 | const DECLARE_BITMAP(cpu_all_bits, NR_CPUS) = CPU_BITS_ALL; |
| 748 | EXPORT_SYMBOL(cpu_all_bits); |
Rusty Russell | b3199c0 | 2008-12-30 09:05:14 +1030 | [diff] [blame] | 749 | |
| 750 | #ifdef CONFIG_INIT_ALL_POSSIBLE |
Rasmus Villemoes | 4b804c8 | 2016-01-20 15:00:19 -0800 | [diff] [blame] | 751 | struct cpumask __cpu_possible_mask __read_mostly |
Rasmus Villemoes | c4c54dd | 2016-01-20 15:00:16 -0800 | [diff] [blame] | 752 | = {CPU_BITS_ALL}; |
Rusty Russell | b3199c0 | 2008-12-30 09:05:14 +1030 | [diff] [blame] | 753 | #else |
Rasmus Villemoes | 4b804c8 | 2016-01-20 15:00:19 -0800 | [diff] [blame] | 754 | struct cpumask __cpu_possible_mask __read_mostly; |
Rusty Russell | b3199c0 | 2008-12-30 09:05:14 +1030 | [diff] [blame] | 755 | #endif |
Rasmus Villemoes | 4b804c8 | 2016-01-20 15:00:19 -0800 | [diff] [blame] | 756 | EXPORT_SYMBOL(__cpu_possible_mask); |
Rusty Russell | b3199c0 | 2008-12-30 09:05:14 +1030 | [diff] [blame] | 757 | |
Rasmus Villemoes | 4b804c8 | 2016-01-20 15:00:19 -0800 | [diff] [blame] | 758 | struct cpumask __cpu_online_mask __read_mostly; |
| 759 | EXPORT_SYMBOL(__cpu_online_mask); |
Rusty Russell | b3199c0 | 2008-12-30 09:05:14 +1030 | [diff] [blame] | 760 | |
Rasmus Villemoes | 4b804c8 | 2016-01-20 15:00:19 -0800 | [diff] [blame] | 761 | struct cpumask __cpu_present_mask __read_mostly; |
| 762 | EXPORT_SYMBOL(__cpu_present_mask); |
Rusty Russell | b3199c0 | 2008-12-30 09:05:14 +1030 | [diff] [blame] | 763 | |
Rasmus Villemoes | 4b804c8 | 2016-01-20 15:00:19 -0800 | [diff] [blame] | 764 | struct cpumask __cpu_active_mask __read_mostly; |
| 765 | EXPORT_SYMBOL(__cpu_active_mask); |
Rusty Russell | 3fa4152 | 2008-12-30 09:05:16 +1030 | [diff] [blame] | 766 | |
Rusty Russell | 3fa4152 | 2008-12-30 09:05:16 +1030 | [diff] [blame] | 767 | void init_cpu_present(const struct cpumask *src) |
| 768 | { |
Rasmus Villemoes | c4c54dd | 2016-01-20 15:00:16 -0800 | [diff] [blame] | 769 | cpumask_copy(&__cpu_present_mask, src); |
Rusty Russell | 3fa4152 | 2008-12-30 09:05:16 +1030 | [diff] [blame] | 770 | } |
| 771 | |
| 772 | void init_cpu_possible(const struct cpumask *src) |
| 773 | { |
Rasmus Villemoes | c4c54dd | 2016-01-20 15:00:16 -0800 | [diff] [blame] | 774 | cpumask_copy(&__cpu_possible_mask, src); |
Rusty Russell | 3fa4152 | 2008-12-30 09:05:16 +1030 | [diff] [blame] | 775 | } |
| 776 | |
| 777 | void init_cpu_online(const struct cpumask *src) |
| 778 | { |
Rasmus Villemoes | c4c54dd | 2016-01-20 15:00:16 -0800 | [diff] [blame] | 779 | cpumask_copy(&__cpu_online_mask, src); |
Rusty Russell | 3fa4152 | 2008-12-30 09:05:16 +1030 | [diff] [blame] | 780 | } |