Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/kernel/timer.c |
| 3 | * |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 4 | * Kernel internal timers, basic process system calls |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 5 | * |
| 6 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 7 | * |
| 8 | * 1997-01-28 Modified by Finn Arne Gangstad to make timers scale better. |
| 9 | * |
| 10 | * 1997-09-10 Updated NTP code according to technical memorandum Jan '96 |
| 11 | * "A Kernel Model for Precision Timekeeping" by Dave Mills |
| 12 | * 1998-12-24 Fixed a xtime SMP race (we need the xtime_lock rw spinlock to |
| 13 | * serialize accesses to xtime/lost_ticks). |
| 14 | * Copyright (C) 1998 Andrea Arcangeli |
| 15 | * 1999-03-10 Improved NTP compatibility by Ulrich Windl |
| 16 | * 2002-05-31 Move sys_sysinfo here and make its locking sane, Robert Love |
| 17 | * 2000-10-05 Implemented scalable SMP per-CPU timer handling. |
| 18 | * Copyright (C) 2000, 2001, 2002 Ingo Molnar |
| 19 | * Designed by David S. Miller, Alexey Kuznetsov and Ingo Molnar |
| 20 | */ |
| 21 | |
| 22 | #include <linux/kernel_stat.h> |
| 23 | #include <linux/module.h> |
| 24 | #include <linux/interrupt.h> |
| 25 | #include <linux/percpu.h> |
| 26 | #include <linux/init.h> |
| 27 | #include <linux/mm.h> |
| 28 | #include <linux/swap.h> |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 29 | #include <linux/pid_namespace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | #include <linux/notifier.h> |
| 31 | #include <linux/thread_info.h> |
| 32 | #include <linux/time.h> |
| 33 | #include <linux/jiffies.h> |
| 34 | #include <linux/posix-timers.h> |
| 35 | #include <linux/cpu.h> |
| 36 | #include <linux/syscalls.h> |
Adrian Bunk | 97a41e2 | 2006-01-08 01:02:17 -0800 | [diff] [blame] | 37 | #include <linux/delay.h> |
Thomas Gleixner | 79bf2bb | 2007-02-16 01:28:03 -0800 | [diff] [blame] | 38 | #include <linux/tick.h> |
Ingo Molnar | 82f67cd | 2007-02-16 01:28:13 -0800 | [diff] [blame] | 39 | #include <linux/kallsyms.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | |
| 41 | #include <asm/uaccess.h> |
| 42 | #include <asm/unistd.h> |
| 43 | #include <asm/div64.h> |
| 44 | #include <asm/timex.h> |
| 45 | #include <asm/io.h> |
| 46 | |
Thomas Gleixner | ecea8d1 | 2005-10-30 15:03:00 -0800 | [diff] [blame] | 47 | u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES; |
| 48 | |
| 49 | EXPORT_SYMBOL(jiffies_64); |
| 50 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | /* |
| 52 | * per-CPU timer vector definitions: |
| 53 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | #define TVN_BITS (CONFIG_BASE_SMALL ? 4 : 6) |
| 55 | #define TVR_BITS (CONFIG_BASE_SMALL ? 6 : 8) |
| 56 | #define TVN_SIZE (1 << TVN_BITS) |
| 57 | #define TVR_SIZE (1 << TVR_BITS) |
| 58 | #define TVN_MASK (TVN_SIZE - 1) |
| 59 | #define TVR_MASK (TVR_SIZE - 1) |
| 60 | |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 61 | struct tvec { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | struct list_head vec[TVN_SIZE]; |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 63 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 65 | struct tvec_root { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | struct list_head vec[TVR_SIZE]; |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 67 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 69 | struct tvec_base { |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 70 | spinlock_t lock; |
| 71 | struct timer_list *running_timer; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 72 | unsigned long timer_jiffies; |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 73 | struct tvec_root tv1; |
| 74 | struct tvec tv2; |
| 75 | struct tvec tv3; |
| 76 | struct tvec tv4; |
| 77 | struct tvec tv5; |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 78 | } ____cacheline_aligned; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 79 | |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 80 | struct tvec_base boot_tvec_bases; |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 81 | EXPORT_SYMBOL(boot_tvec_bases); |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 82 | static DEFINE_PER_CPU(struct tvec_base *, tvec_bases) = &boot_tvec_bases; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 83 | |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 84 | /* |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 85 | * Note that all tvec_bases are 2 byte aligned and lower bit of |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 86 | * base in timer_list is guaranteed to be zero. Use the LSB for |
| 87 | * the new flag to indicate whether the timer is deferrable |
| 88 | */ |
| 89 | #define TBASE_DEFERRABLE_FLAG (0x1) |
| 90 | |
| 91 | /* Functions below help us manage 'deferrable' flag */ |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 92 | static inline unsigned int tbase_get_deferrable(struct tvec_base *base) |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 93 | { |
akpm@linux-foundation.org | e991084 | 2007-05-10 03:16:01 -0700 | [diff] [blame] | 94 | return ((unsigned int)(unsigned long)base & TBASE_DEFERRABLE_FLAG); |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 95 | } |
| 96 | |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 97 | static inline struct tvec_base *tbase_get_base(struct tvec_base *base) |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 98 | { |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 99 | return ((struct tvec_base *)((unsigned long)base & ~TBASE_DEFERRABLE_FLAG)); |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 100 | } |
| 101 | |
| 102 | static inline void timer_set_deferrable(struct timer_list *timer) |
| 103 | { |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 104 | timer->base = ((struct tvec_base *)((unsigned long)(timer->base) | |
Thomas Gleixner | 6819457 | 2007-07-19 01:49:16 -0700 | [diff] [blame] | 105 | TBASE_DEFERRABLE_FLAG)); |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 106 | } |
| 107 | |
| 108 | static inline void |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 109 | timer_set_base(struct timer_list *timer, struct tvec_base *new_base) |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 110 | { |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 111 | timer->base = (struct tvec_base *)((unsigned long)(new_base) | |
Thomas Gleixner | 6819457 | 2007-07-19 01:49:16 -0700 | [diff] [blame] | 112 | tbase_get_deferrable(timer->base)); |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 113 | } |
| 114 | |
Alan Stern | 9c133c4 | 2008-11-06 08:42:48 +0100 | [diff] [blame] | 115 | static unsigned long round_jiffies_common(unsigned long j, int cpu, |
| 116 | bool force_up) |
| 117 | { |
| 118 | int rem; |
| 119 | unsigned long original = j; |
| 120 | |
| 121 | /* |
| 122 | * We don't want all cpus firing their timers at once hitting the |
| 123 | * same lock or cachelines, so we skew each extra cpu with an extra |
| 124 | * 3 jiffies. This 3 jiffies came originally from the mm/ code which |
| 125 | * already did this. |
| 126 | * The skew is done by adding 3*cpunr, then round, then subtract this |
| 127 | * extra offset again. |
| 128 | */ |
| 129 | j += cpu * 3; |
| 130 | |
| 131 | rem = j % HZ; |
| 132 | |
| 133 | /* |
| 134 | * If the target jiffie is just after a whole second (which can happen |
| 135 | * due to delays of the timer irq, long irq off times etc etc) then |
| 136 | * we should round down to the whole second, not up. Use 1/4th second |
| 137 | * as cutoff for this rounding as an extreme upper bound for this. |
| 138 | * But never round down if @force_up is set. |
| 139 | */ |
| 140 | if (rem < HZ/4 && !force_up) /* round down */ |
| 141 | j = j - rem; |
| 142 | else /* round up */ |
| 143 | j = j - rem + HZ; |
| 144 | |
| 145 | /* now that we have rounded, subtract the extra skew again */ |
| 146 | j -= cpu * 3; |
| 147 | |
| 148 | if (j <= jiffies) /* rounding ate our timeout entirely; */ |
| 149 | return original; |
| 150 | return j; |
| 151 | } |
| 152 | |
Arjan van de Ven | 4c36a5d | 2006-12-10 02:21:24 -0800 | [diff] [blame] | 153 | /** |
| 154 | * __round_jiffies - function to round jiffies to a full second |
| 155 | * @j: the time in (absolute) jiffies that should be rounded |
| 156 | * @cpu: the processor number on which the timeout will happen |
| 157 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 158 | * __round_jiffies() rounds an absolute time in the future (in jiffies) |
Arjan van de Ven | 4c36a5d | 2006-12-10 02:21:24 -0800 | [diff] [blame] | 159 | * up or down to (approximately) full seconds. This is useful for timers |
| 160 | * for which the exact time they fire does not matter too much, as long as |
| 161 | * they fire approximately every X seconds. |
| 162 | * |
| 163 | * By rounding these timers to whole seconds, all such timers will fire |
| 164 | * at the same time, rather than at various times spread out. The goal |
| 165 | * of this is to have the CPU wake up less, which saves power. |
| 166 | * |
| 167 | * The exact rounding is skewed for each processor to avoid all |
| 168 | * processors firing at the exact same time, which could lead |
| 169 | * to lock contention or spurious cache line bouncing. |
| 170 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 171 | * The return value is the rounded version of the @j parameter. |
Arjan van de Ven | 4c36a5d | 2006-12-10 02:21:24 -0800 | [diff] [blame] | 172 | */ |
| 173 | unsigned long __round_jiffies(unsigned long j, int cpu) |
| 174 | { |
Alan Stern | 9c133c4 | 2008-11-06 08:42:48 +0100 | [diff] [blame] | 175 | return round_jiffies_common(j, cpu, false); |
Arjan van de Ven | 4c36a5d | 2006-12-10 02:21:24 -0800 | [diff] [blame] | 176 | } |
| 177 | EXPORT_SYMBOL_GPL(__round_jiffies); |
| 178 | |
| 179 | /** |
| 180 | * __round_jiffies_relative - function to round jiffies to a full second |
| 181 | * @j: the time in (relative) jiffies that should be rounded |
| 182 | * @cpu: the processor number on which the timeout will happen |
| 183 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 184 | * __round_jiffies_relative() rounds a time delta in the future (in jiffies) |
Arjan van de Ven | 4c36a5d | 2006-12-10 02:21:24 -0800 | [diff] [blame] | 185 | * up or down to (approximately) full seconds. This is useful for timers |
| 186 | * for which the exact time they fire does not matter too much, as long as |
| 187 | * they fire approximately every X seconds. |
| 188 | * |
| 189 | * By rounding these timers to whole seconds, all such timers will fire |
| 190 | * at the same time, rather than at various times spread out. The goal |
| 191 | * of this is to have the CPU wake up less, which saves power. |
| 192 | * |
| 193 | * The exact rounding is skewed for each processor to avoid all |
| 194 | * processors firing at the exact same time, which could lead |
| 195 | * to lock contention or spurious cache line bouncing. |
| 196 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 197 | * The return value is the rounded version of the @j parameter. |
Arjan van de Ven | 4c36a5d | 2006-12-10 02:21:24 -0800 | [diff] [blame] | 198 | */ |
| 199 | unsigned long __round_jiffies_relative(unsigned long j, int cpu) |
| 200 | { |
Alan Stern | 9c133c4 | 2008-11-06 08:42:48 +0100 | [diff] [blame] | 201 | unsigned long j0 = jiffies; |
| 202 | |
| 203 | /* Use j0 because jiffies might change while we run */ |
| 204 | return round_jiffies_common(j + j0, cpu, false) - j0; |
Arjan van de Ven | 4c36a5d | 2006-12-10 02:21:24 -0800 | [diff] [blame] | 205 | } |
| 206 | EXPORT_SYMBOL_GPL(__round_jiffies_relative); |
| 207 | |
| 208 | /** |
| 209 | * round_jiffies - function to round jiffies to a full second |
| 210 | * @j: the time in (absolute) jiffies that should be rounded |
| 211 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 212 | * round_jiffies() rounds an absolute time in the future (in jiffies) |
Arjan van de Ven | 4c36a5d | 2006-12-10 02:21:24 -0800 | [diff] [blame] | 213 | * up or down to (approximately) full seconds. This is useful for timers |
| 214 | * for which the exact time they fire does not matter too much, as long as |
| 215 | * they fire approximately every X seconds. |
| 216 | * |
| 217 | * By rounding these timers to whole seconds, all such timers will fire |
| 218 | * at the same time, rather than at various times spread out. The goal |
| 219 | * of this is to have the CPU wake up less, which saves power. |
| 220 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 221 | * The return value is the rounded version of the @j parameter. |
Arjan van de Ven | 4c36a5d | 2006-12-10 02:21:24 -0800 | [diff] [blame] | 222 | */ |
| 223 | unsigned long round_jiffies(unsigned long j) |
| 224 | { |
Alan Stern | 9c133c4 | 2008-11-06 08:42:48 +0100 | [diff] [blame] | 225 | return round_jiffies_common(j, raw_smp_processor_id(), false); |
Arjan van de Ven | 4c36a5d | 2006-12-10 02:21:24 -0800 | [diff] [blame] | 226 | } |
| 227 | EXPORT_SYMBOL_GPL(round_jiffies); |
| 228 | |
| 229 | /** |
| 230 | * round_jiffies_relative - function to round jiffies to a full second |
| 231 | * @j: the time in (relative) jiffies that should be rounded |
| 232 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 233 | * round_jiffies_relative() rounds a time delta in the future (in jiffies) |
Arjan van de Ven | 4c36a5d | 2006-12-10 02:21:24 -0800 | [diff] [blame] | 234 | * up or down to (approximately) full seconds. This is useful for timers |
| 235 | * for which the exact time they fire does not matter too much, as long as |
| 236 | * they fire approximately every X seconds. |
| 237 | * |
| 238 | * By rounding these timers to whole seconds, all such timers will fire |
| 239 | * at the same time, rather than at various times spread out. The goal |
| 240 | * of this is to have the CPU wake up less, which saves power. |
| 241 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 242 | * The return value is the rounded version of the @j parameter. |
Arjan van de Ven | 4c36a5d | 2006-12-10 02:21:24 -0800 | [diff] [blame] | 243 | */ |
| 244 | unsigned long round_jiffies_relative(unsigned long j) |
| 245 | { |
| 246 | return __round_jiffies_relative(j, raw_smp_processor_id()); |
| 247 | } |
| 248 | EXPORT_SYMBOL_GPL(round_jiffies_relative); |
| 249 | |
Alan Stern | 9c133c4 | 2008-11-06 08:42:48 +0100 | [diff] [blame] | 250 | /** |
| 251 | * __round_jiffies_up - function to round jiffies up to a full second |
| 252 | * @j: the time in (absolute) jiffies that should be rounded |
| 253 | * @cpu: the processor number on which the timeout will happen |
| 254 | * |
| 255 | * This is the same as __round_jiffies() except that it will never |
| 256 | * round down. This is useful for timeouts for which the exact time |
| 257 | * of firing does not matter too much, as long as they don't fire too |
| 258 | * early. |
| 259 | */ |
| 260 | unsigned long __round_jiffies_up(unsigned long j, int cpu) |
| 261 | { |
| 262 | return round_jiffies_common(j, cpu, true); |
| 263 | } |
| 264 | EXPORT_SYMBOL_GPL(__round_jiffies_up); |
| 265 | |
| 266 | /** |
| 267 | * __round_jiffies_up_relative - function to round jiffies up to a full second |
| 268 | * @j: the time in (relative) jiffies that should be rounded |
| 269 | * @cpu: the processor number on which the timeout will happen |
| 270 | * |
| 271 | * This is the same as __round_jiffies_relative() except that it will never |
| 272 | * round down. This is useful for timeouts for which the exact time |
| 273 | * of firing does not matter too much, as long as they don't fire too |
| 274 | * early. |
| 275 | */ |
| 276 | unsigned long __round_jiffies_up_relative(unsigned long j, int cpu) |
| 277 | { |
| 278 | unsigned long j0 = jiffies; |
| 279 | |
| 280 | /* Use j0 because jiffies might change while we run */ |
| 281 | return round_jiffies_common(j + j0, cpu, true) - j0; |
| 282 | } |
| 283 | EXPORT_SYMBOL_GPL(__round_jiffies_up_relative); |
| 284 | |
| 285 | /** |
| 286 | * round_jiffies_up - function to round jiffies up to a full second |
| 287 | * @j: the time in (absolute) jiffies that should be rounded |
| 288 | * |
| 289 | * This is the same as round_jiffies() except that it will never |
| 290 | * round down. This is useful for timeouts for which the exact time |
| 291 | * of firing does not matter too much, as long as they don't fire too |
| 292 | * early. |
| 293 | */ |
| 294 | unsigned long round_jiffies_up(unsigned long j) |
| 295 | { |
| 296 | return round_jiffies_common(j, raw_smp_processor_id(), true); |
| 297 | } |
| 298 | EXPORT_SYMBOL_GPL(round_jiffies_up); |
| 299 | |
| 300 | /** |
| 301 | * round_jiffies_up_relative - function to round jiffies up to a full second |
| 302 | * @j: the time in (relative) jiffies that should be rounded |
| 303 | * |
| 304 | * This is the same as round_jiffies_relative() except that it will never |
| 305 | * round down. This is useful for timeouts for which the exact time |
| 306 | * of firing does not matter too much, as long as they don't fire too |
| 307 | * early. |
| 308 | */ |
| 309 | unsigned long round_jiffies_up_relative(unsigned long j) |
| 310 | { |
| 311 | return __round_jiffies_up_relative(j, raw_smp_processor_id()); |
| 312 | } |
| 313 | EXPORT_SYMBOL_GPL(round_jiffies_up_relative); |
| 314 | |
Arjan van de Ven | 4c36a5d | 2006-12-10 02:21:24 -0800 | [diff] [blame] | 315 | |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 316 | static inline void set_running_timer(struct tvec_base *base, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 317 | struct timer_list *timer) |
| 318 | { |
| 319 | #ifdef CONFIG_SMP |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 320 | base->running_timer = timer; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | #endif |
| 322 | } |
| 323 | |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 324 | static void internal_add_timer(struct tvec_base *base, struct timer_list *timer) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | { |
| 326 | unsigned long expires = timer->expires; |
| 327 | unsigned long idx = expires - base->timer_jiffies; |
| 328 | struct list_head *vec; |
| 329 | |
| 330 | if (idx < TVR_SIZE) { |
| 331 | int i = expires & TVR_MASK; |
| 332 | vec = base->tv1.vec + i; |
| 333 | } else if (idx < 1 << (TVR_BITS + TVN_BITS)) { |
| 334 | int i = (expires >> TVR_BITS) & TVN_MASK; |
| 335 | vec = base->tv2.vec + i; |
| 336 | } else if (idx < 1 << (TVR_BITS + 2 * TVN_BITS)) { |
| 337 | int i = (expires >> (TVR_BITS + TVN_BITS)) & TVN_MASK; |
| 338 | vec = base->tv3.vec + i; |
| 339 | } else if (idx < 1 << (TVR_BITS + 3 * TVN_BITS)) { |
| 340 | int i = (expires >> (TVR_BITS + 2 * TVN_BITS)) & TVN_MASK; |
| 341 | vec = base->tv4.vec + i; |
| 342 | } else if ((signed long) idx < 0) { |
| 343 | /* |
| 344 | * Can happen if you add a timer with expires == jiffies, |
| 345 | * or you set a timer to go off in the past |
| 346 | */ |
| 347 | vec = base->tv1.vec + (base->timer_jiffies & TVR_MASK); |
| 348 | } else { |
| 349 | int i; |
| 350 | /* If the timeout is larger than 0xffffffff on 64-bit |
| 351 | * architectures then we use the maximum timeout: |
| 352 | */ |
| 353 | if (idx > 0xffffffffUL) { |
| 354 | idx = 0xffffffffUL; |
| 355 | expires = idx + base->timer_jiffies; |
| 356 | } |
| 357 | i = (expires >> (TVR_BITS + 3 * TVN_BITS)) & TVN_MASK; |
| 358 | vec = base->tv5.vec + i; |
| 359 | } |
| 360 | /* |
| 361 | * Timers are FIFO: |
| 362 | */ |
| 363 | list_add_tail(&timer->entry, vec); |
| 364 | } |
| 365 | |
Ingo Molnar | 82f67cd | 2007-02-16 01:28:13 -0800 | [diff] [blame] | 366 | #ifdef CONFIG_TIMER_STATS |
| 367 | void __timer_stats_timer_set_start_info(struct timer_list *timer, void *addr) |
| 368 | { |
| 369 | if (timer->start_site) |
| 370 | return; |
| 371 | |
| 372 | timer->start_site = addr; |
| 373 | memcpy(timer->start_comm, current->comm, TASK_COMM_LEN); |
| 374 | timer->start_pid = current->pid; |
| 375 | } |
Venki Pallipadi | c5c061b8 | 2007-07-15 23:40:30 -0700 | [diff] [blame] | 376 | |
| 377 | static void timer_stats_account_timer(struct timer_list *timer) |
| 378 | { |
| 379 | unsigned int flag = 0; |
| 380 | |
| 381 | if (unlikely(tbase_get_deferrable(timer->base))) |
| 382 | flag |= TIMER_STATS_FLAG_DEFERRABLE; |
| 383 | |
| 384 | timer_stats_update_stats(timer, timer->start_pid, timer->start_site, |
| 385 | timer->function, timer->start_comm, flag); |
| 386 | } |
| 387 | |
| 388 | #else |
| 389 | static void timer_stats_account_timer(struct timer_list *timer) {} |
Ingo Molnar | 82f67cd | 2007-02-16 01:28:13 -0800 | [diff] [blame] | 390 | #endif |
| 391 | |
Thomas Gleixner | c6f3a97 | 2008-04-30 00:55:03 -0700 | [diff] [blame] | 392 | #ifdef CONFIG_DEBUG_OBJECTS_TIMERS |
| 393 | |
| 394 | static struct debug_obj_descr timer_debug_descr; |
| 395 | |
| 396 | /* |
| 397 | * fixup_init is called when: |
| 398 | * - an active object is initialized |
| 399 | */ |
| 400 | static int timer_fixup_init(void *addr, enum debug_obj_state state) |
| 401 | { |
| 402 | struct timer_list *timer = addr; |
| 403 | |
| 404 | switch (state) { |
| 405 | case ODEBUG_STATE_ACTIVE: |
| 406 | del_timer_sync(timer); |
| 407 | debug_object_init(timer, &timer_debug_descr); |
| 408 | return 1; |
| 409 | default: |
| 410 | return 0; |
| 411 | } |
| 412 | } |
| 413 | |
| 414 | /* |
| 415 | * fixup_activate is called when: |
| 416 | * - an active object is activated |
| 417 | * - an unknown object is activated (might be a statically initialized object) |
| 418 | */ |
| 419 | static int timer_fixup_activate(void *addr, enum debug_obj_state state) |
| 420 | { |
| 421 | struct timer_list *timer = addr; |
| 422 | |
| 423 | switch (state) { |
| 424 | |
| 425 | case ODEBUG_STATE_NOTAVAILABLE: |
| 426 | /* |
| 427 | * This is not really a fixup. The timer was |
| 428 | * statically initialized. We just make sure that it |
| 429 | * is tracked in the object tracker. |
| 430 | */ |
| 431 | if (timer->entry.next == NULL && |
| 432 | timer->entry.prev == TIMER_ENTRY_STATIC) { |
| 433 | debug_object_init(timer, &timer_debug_descr); |
| 434 | debug_object_activate(timer, &timer_debug_descr); |
| 435 | return 0; |
| 436 | } else { |
| 437 | WARN_ON_ONCE(1); |
| 438 | } |
| 439 | return 0; |
| 440 | |
| 441 | case ODEBUG_STATE_ACTIVE: |
| 442 | WARN_ON(1); |
| 443 | |
| 444 | default: |
| 445 | return 0; |
| 446 | } |
| 447 | } |
| 448 | |
| 449 | /* |
| 450 | * fixup_free is called when: |
| 451 | * - an active object is freed |
| 452 | */ |
| 453 | static int timer_fixup_free(void *addr, enum debug_obj_state state) |
| 454 | { |
| 455 | struct timer_list *timer = addr; |
| 456 | |
| 457 | switch (state) { |
| 458 | case ODEBUG_STATE_ACTIVE: |
| 459 | del_timer_sync(timer); |
| 460 | debug_object_free(timer, &timer_debug_descr); |
| 461 | return 1; |
| 462 | default: |
| 463 | return 0; |
| 464 | } |
| 465 | } |
| 466 | |
| 467 | static struct debug_obj_descr timer_debug_descr = { |
| 468 | .name = "timer_list", |
| 469 | .fixup_init = timer_fixup_init, |
| 470 | .fixup_activate = timer_fixup_activate, |
| 471 | .fixup_free = timer_fixup_free, |
| 472 | }; |
| 473 | |
| 474 | static inline void debug_timer_init(struct timer_list *timer) |
| 475 | { |
| 476 | debug_object_init(timer, &timer_debug_descr); |
| 477 | } |
| 478 | |
| 479 | static inline void debug_timer_activate(struct timer_list *timer) |
| 480 | { |
| 481 | debug_object_activate(timer, &timer_debug_descr); |
| 482 | } |
| 483 | |
| 484 | static inline void debug_timer_deactivate(struct timer_list *timer) |
| 485 | { |
| 486 | debug_object_deactivate(timer, &timer_debug_descr); |
| 487 | } |
| 488 | |
| 489 | static inline void debug_timer_free(struct timer_list *timer) |
| 490 | { |
| 491 | debug_object_free(timer, &timer_debug_descr); |
| 492 | } |
| 493 | |
| 494 | static void __init_timer(struct timer_list *timer); |
| 495 | |
| 496 | void init_timer_on_stack(struct timer_list *timer) |
| 497 | { |
| 498 | debug_object_init_on_stack(timer, &timer_debug_descr); |
| 499 | __init_timer(timer); |
| 500 | } |
| 501 | EXPORT_SYMBOL_GPL(init_timer_on_stack); |
| 502 | |
| 503 | void destroy_timer_on_stack(struct timer_list *timer) |
| 504 | { |
| 505 | debug_object_free(timer, &timer_debug_descr); |
| 506 | } |
| 507 | EXPORT_SYMBOL_GPL(destroy_timer_on_stack); |
| 508 | |
| 509 | #else |
| 510 | static inline void debug_timer_init(struct timer_list *timer) { } |
| 511 | static inline void debug_timer_activate(struct timer_list *timer) { } |
| 512 | static inline void debug_timer_deactivate(struct timer_list *timer) { } |
| 513 | #endif |
| 514 | |
| 515 | static void __init_timer(struct timer_list *timer) |
| 516 | { |
| 517 | timer->entry.next = NULL; |
| 518 | timer->base = __raw_get_cpu_var(tvec_bases); |
| 519 | #ifdef CONFIG_TIMER_STATS |
| 520 | timer->start_site = NULL; |
| 521 | timer->start_pid = -1; |
| 522 | memset(timer->start_comm, 0, TASK_COMM_LEN); |
| 523 | #endif |
| 524 | } |
| 525 | |
Rolf Eike Beer | 2aae4a1 | 2006-09-29 01:59:46 -0700 | [diff] [blame] | 526 | /** |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 527 | * init_timer - initialize a timer. |
| 528 | * @timer: the timer to be initialized |
| 529 | * |
| 530 | * init_timer() must be done to a timer prior calling *any* of the |
| 531 | * other timer functions. |
| 532 | */ |
Harvey Harrison | 7ad5b3a | 2008-02-08 04:19:53 -0800 | [diff] [blame] | 533 | void init_timer(struct timer_list *timer) |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 534 | { |
Thomas Gleixner | c6f3a97 | 2008-04-30 00:55:03 -0700 | [diff] [blame] | 535 | debug_timer_init(timer); |
| 536 | __init_timer(timer); |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 537 | } |
| 538 | EXPORT_SYMBOL(init_timer); |
| 539 | |
Harvey Harrison | 7ad5b3a | 2008-02-08 04:19:53 -0800 | [diff] [blame] | 540 | void init_timer_deferrable(struct timer_list *timer) |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 541 | { |
| 542 | init_timer(timer); |
| 543 | timer_set_deferrable(timer); |
| 544 | } |
| 545 | EXPORT_SYMBOL(init_timer_deferrable); |
| 546 | |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 547 | static inline void detach_timer(struct timer_list *timer, |
Ingo Molnar | 82f67cd | 2007-02-16 01:28:13 -0800 | [diff] [blame] | 548 | int clear_pending) |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 549 | { |
| 550 | struct list_head *entry = &timer->entry; |
| 551 | |
Thomas Gleixner | c6f3a97 | 2008-04-30 00:55:03 -0700 | [diff] [blame] | 552 | debug_timer_deactivate(timer); |
| 553 | |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 554 | __list_del(entry->prev, entry->next); |
| 555 | if (clear_pending) |
| 556 | entry->next = NULL; |
| 557 | entry->prev = LIST_POISON2; |
| 558 | } |
| 559 | |
| 560 | /* |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 561 | * We are using hashed locking: holding per_cpu(tvec_bases).lock |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 562 | * means that all timers which are tied to this base via timer->base are |
| 563 | * locked, and the base itself is locked too. |
| 564 | * |
| 565 | * So __run_timers/migrate_timers can safely modify all timers which could |
| 566 | * be found on ->tvX lists. |
| 567 | * |
| 568 | * When the timer's base is locked, and the timer removed from list, it is |
| 569 | * possible to set timer->base = NULL and drop the lock: the timer remains |
| 570 | * locked. |
| 571 | */ |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 572 | static struct tvec_base *lock_timer_base(struct timer_list *timer, |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 573 | unsigned long *flags) |
Josh Triplett | 89e7e374 | 2006-09-29 01:59:36 -0700 | [diff] [blame] | 574 | __acquires(timer->base->lock) |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 575 | { |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 576 | struct tvec_base *base; |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 577 | |
| 578 | for (;;) { |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 579 | struct tvec_base *prelock_base = timer->base; |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 580 | base = tbase_get_base(prelock_base); |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 581 | if (likely(base != NULL)) { |
| 582 | spin_lock_irqsave(&base->lock, *flags); |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 583 | if (likely(prelock_base == timer->base)) |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 584 | return base; |
| 585 | /* The timer has migrated to another CPU */ |
| 586 | spin_unlock_irqrestore(&base->lock, *flags); |
| 587 | } |
| 588 | cpu_relax(); |
| 589 | } |
| 590 | } |
| 591 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 592 | int __mod_timer(struct timer_list *timer, unsigned long expires) |
| 593 | { |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 594 | struct tvec_base *base, *new_base; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 595 | unsigned long flags; |
| 596 | int ret = 0; |
| 597 | |
Ingo Molnar | 82f67cd | 2007-02-16 01:28:13 -0800 | [diff] [blame] | 598 | timer_stats_timer_set_start_info(timer); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 599 | BUG_ON(!timer->function); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 600 | |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 601 | base = lock_timer_base(timer, &flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 602 | |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 603 | if (timer_pending(timer)) { |
| 604 | detach_timer(timer, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 605 | ret = 1; |
| 606 | } |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 607 | |
Thomas Gleixner | c6f3a97 | 2008-04-30 00:55:03 -0700 | [diff] [blame] | 608 | debug_timer_activate(timer); |
| 609 | |
Jan Beulich | a4a6198 | 2006-03-24 03:15:54 -0800 | [diff] [blame] | 610 | new_base = __get_cpu_var(tvec_bases); |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 611 | |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 612 | if (base != new_base) { |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 613 | /* |
| 614 | * We are trying to schedule the timer on the local CPU. |
| 615 | * However we can't change timer's base while it is running, |
| 616 | * otherwise del_timer_sync() can't detect that the timer's |
| 617 | * handler yet has not finished. This also guarantees that |
| 618 | * the timer is serialized wrt itself. |
| 619 | */ |
Oleg Nesterov | a2c348f | 2006-03-31 02:30:31 -0800 | [diff] [blame] | 620 | if (likely(base->running_timer != timer)) { |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 621 | /* See the comment in lock_timer_base() */ |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 622 | timer_set_base(timer, NULL); |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 623 | spin_unlock(&base->lock); |
Oleg Nesterov | a2c348f | 2006-03-31 02:30:31 -0800 | [diff] [blame] | 624 | base = new_base; |
| 625 | spin_lock(&base->lock); |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 626 | timer_set_base(timer, base); |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 627 | } |
| 628 | } |
| 629 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 630 | timer->expires = expires; |
Oleg Nesterov | a2c348f | 2006-03-31 02:30:31 -0800 | [diff] [blame] | 631 | internal_add_timer(base, timer); |
| 632 | spin_unlock_irqrestore(&base->lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 633 | |
| 634 | return ret; |
| 635 | } |
| 636 | |
| 637 | EXPORT_SYMBOL(__mod_timer); |
| 638 | |
Rolf Eike Beer | 2aae4a1 | 2006-09-29 01:59:46 -0700 | [diff] [blame] | 639 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 640 | * add_timer_on - start a timer on a particular CPU |
| 641 | * @timer: the timer to be added |
| 642 | * @cpu: the CPU to start it on |
| 643 | * |
| 644 | * This is not very scalable on SMP. Double adds are not possible. |
| 645 | */ |
| 646 | void add_timer_on(struct timer_list *timer, int cpu) |
| 647 | { |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 648 | struct tvec_base *base = per_cpu(tvec_bases, cpu); |
Thomas Gleixner | 6819457 | 2007-07-19 01:49:16 -0700 | [diff] [blame] | 649 | unsigned long flags; |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 650 | |
Ingo Molnar | 82f67cd | 2007-02-16 01:28:13 -0800 | [diff] [blame] | 651 | timer_stats_timer_set_start_info(timer); |
Thomas Gleixner | 6819457 | 2007-07-19 01:49:16 -0700 | [diff] [blame] | 652 | BUG_ON(timer_pending(timer) || !timer->function); |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 653 | spin_lock_irqsave(&base->lock, flags); |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 654 | timer_set_base(timer, base); |
Thomas Gleixner | c6f3a97 | 2008-04-30 00:55:03 -0700 | [diff] [blame] | 655 | debug_timer_activate(timer); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 656 | internal_add_timer(base, timer); |
Thomas Gleixner | 06d8308 | 2008-03-22 09:20:24 +0100 | [diff] [blame] | 657 | /* |
| 658 | * Check whether the other CPU is idle and needs to be |
| 659 | * triggered to reevaluate the timer wheel when nohz is |
| 660 | * active. We are protected against the other CPU fiddling |
| 661 | * with the timer by holding the timer base lock. This also |
| 662 | * makes sure that a CPU on the way to idle can not evaluate |
| 663 | * the timer wheel. |
| 664 | */ |
| 665 | wake_up_idle_cpu(cpu); |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 666 | spin_unlock_irqrestore(&base->lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 667 | } |
| 668 | |
Rolf Eike Beer | 2aae4a1 | 2006-09-29 01:59:46 -0700 | [diff] [blame] | 669 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 670 | * mod_timer - modify a timer's timeout |
| 671 | * @timer: the timer to be modified |
Rolf Eike Beer | 2aae4a1 | 2006-09-29 01:59:46 -0700 | [diff] [blame] | 672 | * @expires: new timeout in jiffies |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 673 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 674 | * mod_timer() is a more efficient way to update the expire field of an |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 675 | * active timer (if the timer is inactive it will be activated) |
| 676 | * |
| 677 | * mod_timer(timer, expires) is equivalent to: |
| 678 | * |
| 679 | * del_timer(timer); timer->expires = expires; add_timer(timer); |
| 680 | * |
| 681 | * Note that if there are multiple unserialized concurrent users of the |
| 682 | * same timer, then mod_timer() is the only safe way to modify the timeout, |
| 683 | * since add_timer() cannot modify an already running timer. |
| 684 | * |
| 685 | * The function returns whether it has modified a pending timer or not. |
| 686 | * (ie. mod_timer() of an inactive timer returns 0, mod_timer() of an |
| 687 | * active timer returns 1.) |
| 688 | */ |
| 689 | int mod_timer(struct timer_list *timer, unsigned long expires) |
| 690 | { |
| 691 | BUG_ON(!timer->function); |
| 692 | |
Ingo Molnar | 82f67cd | 2007-02-16 01:28:13 -0800 | [diff] [blame] | 693 | timer_stats_timer_set_start_info(timer); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 694 | /* |
| 695 | * This is a common optimization triggered by the |
| 696 | * networking code - if the timer is re-modified |
| 697 | * to be the same thing then just return: |
| 698 | */ |
| 699 | if (timer->expires == expires && timer_pending(timer)) |
| 700 | return 1; |
| 701 | |
| 702 | return __mod_timer(timer, expires); |
| 703 | } |
| 704 | |
| 705 | EXPORT_SYMBOL(mod_timer); |
| 706 | |
Rolf Eike Beer | 2aae4a1 | 2006-09-29 01:59:46 -0700 | [diff] [blame] | 707 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 708 | * del_timer - deactive a timer. |
| 709 | * @timer: the timer to be deactivated |
| 710 | * |
| 711 | * del_timer() deactivates a timer - this works on both active and inactive |
| 712 | * timers. |
| 713 | * |
| 714 | * The function returns whether it has deactivated a pending timer or not. |
| 715 | * (ie. del_timer() of an inactive timer returns 0, del_timer() of an |
| 716 | * active timer returns 1.) |
| 717 | */ |
| 718 | int del_timer(struct timer_list *timer) |
| 719 | { |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 720 | struct tvec_base *base; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 721 | unsigned long flags; |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 722 | int ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 723 | |
Ingo Molnar | 82f67cd | 2007-02-16 01:28:13 -0800 | [diff] [blame] | 724 | timer_stats_timer_clear_start_info(timer); |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 725 | if (timer_pending(timer)) { |
| 726 | base = lock_timer_base(timer, &flags); |
| 727 | if (timer_pending(timer)) { |
| 728 | detach_timer(timer, 1); |
| 729 | ret = 1; |
| 730 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 731 | spin_unlock_irqrestore(&base->lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 732 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 733 | |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 734 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 735 | } |
| 736 | |
| 737 | EXPORT_SYMBOL(del_timer); |
| 738 | |
| 739 | #ifdef CONFIG_SMP |
Rolf Eike Beer | 2aae4a1 | 2006-09-29 01:59:46 -0700 | [diff] [blame] | 740 | /** |
| 741 | * try_to_del_timer_sync - Try to deactivate a timer |
| 742 | * @timer: timer do del |
| 743 | * |
Oleg Nesterov | fd450b7 | 2005-06-23 00:08:59 -0700 | [diff] [blame] | 744 | * This function tries to deactivate a timer. Upon successful (ret >= 0) |
| 745 | * exit the timer is not queued and the handler is not running on any CPU. |
| 746 | * |
| 747 | * It must not be called from interrupt contexts. |
| 748 | */ |
| 749 | int try_to_del_timer_sync(struct timer_list *timer) |
| 750 | { |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 751 | struct tvec_base *base; |
Oleg Nesterov | fd450b7 | 2005-06-23 00:08:59 -0700 | [diff] [blame] | 752 | unsigned long flags; |
| 753 | int ret = -1; |
| 754 | |
| 755 | base = lock_timer_base(timer, &flags); |
| 756 | |
| 757 | if (base->running_timer == timer) |
| 758 | goto out; |
| 759 | |
| 760 | ret = 0; |
| 761 | if (timer_pending(timer)) { |
| 762 | detach_timer(timer, 1); |
| 763 | ret = 1; |
| 764 | } |
| 765 | out: |
| 766 | spin_unlock_irqrestore(&base->lock, flags); |
| 767 | |
| 768 | return ret; |
| 769 | } |
| 770 | |
David Howells | e19dff1 | 2007-04-26 15:46:56 -0700 | [diff] [blame] | 771 | EXPORT_SYMBOL(try_to_del_timer_sync); |
| 772 | |
Rolf Eike Beer | 2aae4a1 | 2006-09-29 01:59:46 -0700 | [diff] [blame] | 773 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 774 | * del_timer_sync - deactivate a timer and wait for the handler to finish. |
| 775 | * @timer: the timer to be deactivated |
| 776 | * |
| 777 | * This function only differs from del_timer() on SMP: besides deactivating |
| 778 | * the timer it also makes sure the handler has finished executing on other |
| 779 | * CPUs. |
| 780 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 781 | * Synchronization rules: Callers must prevent restarting of the timer, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 782 | * otherwise this function is meaningless. It must not be called from |
| 783 | * interrupt contexts. The caller must not hold locks which would prevent |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 784 | * completion of the timer's handler. The timer's handler must not call |
| 785 | * add_timer_on(). Upon exit the timer is not queued and the handler is |
| 786 | * not running on any CPU. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 787 | * |
| 788 | * The function returns whether it has deactivated a pending timer or not. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 789 | */ |
| 790 | int del_timer_sync(struct timer_list *timer) |
| 791 | { |
Oleg Nesterov | fd450b7 | 2005-06-23 00:08:59 -0700 | [diff] [blame] | 792 | for (;;) { |
| 793 | int ret = try_to_del_timer_sync(timer); |
| 794 | if (ret >= 0) |
| 795 | return ret; |
Andrew Morton | a000965 | 2006-07-14 00:24:06 -0700 | [diff] [blame] | 796 | cpu_relax(); |
Oleg Nesterov | fd450b7 | 2005-06-23 00:08:59 -0700 | [diff] [blame] | 797 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 798 | } |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 799 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 800 | EXPORT_SYMBOL(del_timer_sync); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 801 | #endif |
| 802 | |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 803 | static int cascade(struct tvec_base *base, struct tvec *tv, int index) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 804 | { |
| 805 | /* cascade all the timers from tv up one level */ |
Porpoise | 3439dd8 | 2006-06-23 02:05:56 -0700 | [diff] [blame] | 806 | struct timer_list *timer, *tmp; |
| 807 | struct list_head tv_list; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 808 | |
Porpoise | 3439dd8 | 2006-06-23 02:05:56 -0700 | [diff] [blame] | 809 | list_replace_init(tv->vec + index, &tv_list); |
| 810 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 811 | /* |
Porpoise | 3439dd8 | 2006-06-23 02:05:56 -0700 | [diff] [blame] | 812 | * We are removing _all_ timers from the list, so we |
| 813 | * don't have to detach them individually. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 814 | */ |
Porpoise | 3439dd8 | 2006-06-23 02:05:56 -0700 | [diff] [blame] | 815 | list_for_each_entry_safe(timer, tmp, &tv_list, entry) { |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 816 | BUG_ON(tbase_get_base(timer->base) != base); |
Porpoise | 3439dd8 | 2006-06-23 02:05:56 -0700 | [diff] [blame] | 817 | internal_add_timer(base, timer); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 818 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 819 | |
| 820 | return index; |
| 821 | } |
| 822 | |
Rolf Eike Beer | 2aae4a1 | 2006-09-29 01:59:46 -0700 | [diff] [blame] | 823 | #define INDEX(N) ((base->timer_jiffies >> (TVR_BITS + (N) * TVN_BITS)) & TVN_MASK) |
| 824 | |
| 825 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 826 | * __run_timers - run all expired timers (if any) on this CPU. |
| 827 | * @base: the timer vector to be processed. |
| 828 | * |
| 829 | * This function cascades all vectors and executes all expired timer |
| 830 | * vectors. |
| 831 | */ |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 832 | static inline void __run_timers(struct tvec_base *base) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 833 | { |
| 834 | struct timer_list *timer; |
| 835 | |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 836 | spin_lock_irq(&base->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 837 | while (time_after_eq(jiffies, base->timer_jiffies)) { |
Oleg Nesterov | 626ab0e | 2006-06-23 02:05:55 -0700 | [diff] [blame] | 838 | struct list_head work_list; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 839 | struct list_head *head = &work_list; |
Thomas Gleixner | 6819457 | 2007-07-19 01:49:16 -0700 | [diff] [blame] | 840 | int index = base->timer_jiffies & TVR_MASK; |
Oleg Nesterov | 626ab0e | 2006-06-23 02:05:55 -0700 | [diff] [blame] | 841 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 842 | /* |
| 843 | * Cascade timers: |
| 844 | */ |
| 845 | if (!index && |
| 846 | (!cascade(base, &base->tv2, INDEX(0))) && |
| 847 | (!cascade(base, &base->tv3, INDEX(1))) && |
| 848 | !cascade(base, &base->tv4, INDEX(2))) |
| 849 | cascade(base, &base->tv5, INDEX(3)); |
Oleg Nesterov | 626ab0e | 2006-06-23 02:05:55 -0700 | [diff] [blame] | 850 | ++base->timer_jiffies; |
| 851 | list_replace_init(base->tv1.vec + index, &work_list); |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 852 | while (!list_empty(head)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 853 | void (*fn)(unsigned long); |
| 854 | unsigned long data; |
| 855 | |
Pavel Emelianov | b5e6181 | 2007-05-08 00:30:19 -0700 | [diff] [blame] | 856 | timer = list_first_entry(head, struct timer_list,entry); |
Thomas Gleixner | 6819457 | 2007-07-19 01:49:16 -0700 | [diff] [blame] | 857 | fn = timer->function; |
| 858 | data = timer->data; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 859 | |
Ingo Molnar | 82f67cd | 2007-02-16 01:28:13 -0800 | [diff] [blame] | 860 | timer_stats_account_timer(timer); |
| 861 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 862 | set_running_timer(base, timer); |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 863 | detach_timer(timer, 1); |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 864 | spin_unlock_irq(&base->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 865 | { |
Jesper Juhl | be5b4fb | 2005-06-23 00:09:09 -0700 | [diff] [blame] | 866 | int preempt_count = preempt_count(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 867 | fn(data); |
| 868 | if (preempt_count != preempt_count()) { |
Pavel Machek | 4c9dc64 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 869 | printk(KERN_ERR "huh, entered %p " |
Jesper Juhl | be5b4fb | 2005-06-23 00:09:09 -0700 | [diff] [blame] | 870 | "with preempt_count %08x, exited" |
| 871 | " with %08x?\n", |
| 872 | fn, preempt_count, |
| 873 | preempt_count()); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 874 | BUG(); |
| 875 | } |
| 876 | } |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 877 | spin_lock_irq(&base->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 878 | } |
| 879 | } |
| 880 | set_running_timer(base, NULL); |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 881 | spin_unlock_irq(&base->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 882 | } |
| 883 | |
Russell King | ee9c578 | 2008-04-20 13:59:33 +0100 | [diff] [blame] | 884 | #ifdef CONFIG_NO_HZ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 885 | /* |
| 886 | * Find out when the next timer event is due to happen. This |
| 887 | * is used on S/390 to stop all activity when a cpus is idle. |
| 888 | * This functions needs to be called disabled. |
| 889 | */ |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 890 | static unsigned long __next_timer_interrupt(struct tvec_base *base) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 891 | { |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 892 | unsigned long timer_jiffies = base->timer_jiffies; |
Thomas Gleixner | eaad084 | 2007-05-29 23:47:39 +0200 | [diff] [blame] | 893 | unsigned long expires = timer_jiffies + NEXT_TIMER_MAX_DELTA; |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 894 | int index, slot, array, found = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 895 | struct timer_list *nte; |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 896 | struct tvec *varray[4]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 897 | |
| 898 | /* Look for timer events in tv1. */ |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 899 | index = slot = timer_jiffies & TVR_MASK; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 900 | do { |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 901 | list_for_each_entry(nte, base->tv1.vec + slot, entry) { |
Thomas Gleixner | 6819457 | 2007-07-19 01:49:16 -0700 | [diff] [blame] | 902 | if (tbase_get_deferrable(nte->base)) |
| 903 | continue; |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 904 | |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 905 | found = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 906 | expires = nte->expires; |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 907 | /* Look at the cascade bucket(s)? */ |
| 908 | if (!index || slot < index) |
| 909 | goto cascade; |
| 910 | return expires; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 911 | } |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 912 | slot = (slot + 1) & TVR_MASK; |
| 913 | } while (slot != index); |
| 914 | |
| 915 | cascade: |
| 916 | /* Calculate the next cascade event */ |
| 917 | if (index) |
| 918 | timer_jiffies += TVR_SIZE - index; |
| 919 | timer_jiffies >>= TVR_BITS; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 920 | |
| 921 | /* Check tv2-tv5. */ |
| 922 | varray[0] = &base->tv2; |
| 923 | varray[1] = &base->tv3; |
| 924 | varray[2] = &base->tv4; |
| 925 | varray[3] = &base->tv5; |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 926 | |
| 927 | for (array = 0; array < 4; array++) { |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 928 | struct tvec *varp = varray[array]; |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 929 | |
| 930 | index = slot = timer_jiffies & TVN_MASK; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 931 | do { |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 932 | list_for_each_entry(nte, varp->vec + slot, entry) { |
| 933 | found = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 934 | if (time_before(nte->expires, expires)) |
| 935 | expires = nte->expires; |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 936 | } |
| 937 | /* |
| 938 | * Do we still search for the first timer or are |
| 939 | * we looking up the cascade buckets ? |
| 940 | */ |
| 941 | if (found) { |
| 942 | /* Look at the cascade bucket(s)? */ |
| 943 | if (!index || slot < index) |
| 944 | break; |
| 945 | return expires; |
| 946 | } |
| 947 | slot = (slot + 1) & TVN_MASK; |
| 948 | } while (slot != index); |
| 949 | |
| 950 | if (index) |
| 951 | timer_jiffies += TVN_SIZE - index; |
| 952 | timer_jiffies >>= TVN_BITS; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 953 | } |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 954 | return expires; |
| 955 | } |
| 956 | |
| 957 | /* |
| 958 | * Check, if the next hrtimer event is before the next timer wheel |
| 959 | * event: |
| 960 | */ |
| 961 | static unsigned long cmp_next_hrtimer_event(unsigned long now, |
| 962 | unsigned long expires) |
| 963 | { |
| 964 | ktime_t hr_delta = hrtimer_get_next_event(); |
| 965 | struct timespec tsdelta; |
Thomas Gleixner | 9501b6c | 2007-03-25 14:31:17 +0200 | [diff] [blame] | 966 | unsigned long delta; |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 967 | |
| 968 | if (hr_delta.tv64 == KTIME_MAX) |
| 969 | return expires; |
| 970 | |
Thomas Gleixner | 9501b6c | 2007-03-25 14:31:17 +0200 | [diff] [blame] | 971 | /* |
| 972 | * Expired timer available, let it expire in the next tick |
| 973 | */ |
| 974 | if (hr_delta.tv64 <= 0) |
| 975 | return now + 1; |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 976 | |
| 977 | tsdelta = ktime_to_timespec(hr_delta); |
Thomas Gleixner | 9501b6c | 2007-03-25 14:31:17 +0200 | [diff] [blame] | 978 | delta = timespec_to_jiffies(&tsdelta); |
Thomas Gleixner | eaad084 | 2007-05-29 23:47:39 +0200 | [diff] [blame] | 979 | |
| 980 | /* |
| 981 | * Limit the delta to the max value, which is checked in |
| 982 | * tick_nohz_stop_sched_tick(): |
| 983 | */ |
| 984 | if (delta > NEXT_TIMER_MAX_DELTA) |
| 985 | delta = NEXT_TIMER_MAX_DELTA; |
| 986 | |
Thomas Gleixner | 9501b6c | 2007-03-25 14:31:17 +0200 | [diff] [blame] | 987 | /* |
| 988 | * Take rounding errors in to account and make sure, that it |
| 989 | * expires in the next tick. Otherwise we go into an endless |
| 990 | * ping pong due to tick_nohz_stop_sched_tick() retriggering |
| 991 | * the timer softirq |
| 992 | */ |
| 993 | if (delta < 1) |
| 994 | delta = 1; |
| 995 | now += delta; |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 996 | if (time_before(now, expires)) |
| 997 | return now; |
| 998 | return expires; |
| 999 | } |
| 1000 | |
| 1001 | /** |
Li Zefan | 8dce39c | 2007-11-05 14:51:10 -0800 | [diff] [blame] | 1002 | * get_next_timer_interrupt - return the jiffy of the next pending timer |
Randy Dunlap | 05fb6bf | 2007-02-28 20:12:13 -0800 | [diff] [blame] | 1003 | * @now: current time (in jiffies) |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 1004 | */ |
Thomas Gleixner | fd064b9 | 2007-02-16 01:27:47 -0800 | [diff] [blame] | 1005 | unsigned long get_next_timer_interrupt(unsigned long now) |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 1006 | { |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 1007 | struct tvec_base *base = __get_cpu_var(tvec_bases); |
Thomas Gleixner | fd064b9 | 2007-02-16 01:27:47 -0800 | [diff] [blame] | 1008 | unsigned long expires; |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 1009 | |
| 1010 | spin_lock(&base->lock); |
| 1011 | expires = __next_timer_interrupt(base); |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 1012 | spin_unlock(&base->lock); |
Tony Lindgren | 6923974 | 2006-03-06 15:42:45 -0800 | [diff] [blame] | 1013 | |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 1014 | if (time_before_eq(expires, now)) |
| 1015 | return now; |
Zachary Amsden | 0662b71 | 2006-05-20 15:00:24 -0700 | [diff] [blame] | 1016 | |
Thomas Gleixner | 1cfd684 | 2007-02-16 01:27:46 -0800 | [diff] [blame] | 1017 | return cmp_next_hrtimer_event(now, expires); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1018 | } |
| 1019 | #endif |
| 1020 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1021 | /* |
Daniel Walker | 5b4db0c | 2007-10-18 03:06:11 -0700 | [diff] [blame] | 1022 | * Called from the timer interrupt handler to charge one tick to the current |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1023 | * process. user_tick is 1 if the tick is user time, 0 for system. |
| 1024 | */ |
| 1025 | void update_process_times(int user_tick) |
| 1026 | { |
| 1027 | struct task_struct *p = current; |
| 1028 | int cpu = smp_processor_id(); |
| 1029 | |
| 1030 | /* Note: this timer irq context must be accounted for as well. */ |
Paul Mackerras | fa13a5a | 2007-11-09 22:39:38 +0100 | [diff] [blame] | 1031 | account_process_tick(p, user_tick); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1032 | run_local_timers(); |
| 1033 | if (rcu_pending(cpu)) |
| 1034 | rcu_check_callbacks(cpu, user_tick); |
Peter Zijlstra | b845b51 | 2008-08-08 21:47:09 +0200 | [diff] [blame] | 1035 | printk_tick(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1036 | scheduler_tick(); |
Thomas Gleixner | 6819457 | 2007-07-19 01:49:16 -0700 | [diff] [blame] | 1037 | run_posix_cpu_timers(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1038 | } |
| 1039 | |
| 1040 | /* |
| 1041 | * Nr of active tasks - counted in fixed-point numbers |
| 1042 | */ |
| 1043 | static unsigned long count_active_tasks(void) |
| 1044 | { |
Jack Steiner | db1b1fe | 2006-03-31 02:31:21 -0800 | [diff] [blame] | 1045 | return nr_active() * FIXED_1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1046 | } |
| 1047 | |
| 1048 | /* |
| 1049 | * Hmm.. Changed this, as the GNU make sources (load.c) seems to |
| 1050 | * imply that avenrun[] is the standard name for this kind of thing. |
| 1051 | * Nothing else seems to be standardized: the fractional size etc |
| 1052 | * all seem to differ on different machines. |
| 1053 | * |
| 1054 | * Requires xtime_lock to access. |
| 1055 | */ |
| 1056 | unsigned long avenrun[3]; |
| 1057 | |
| 1058 | EXPORT_SYMBOL(avenrun); |
| 1059 | |
| 1060 | /* |
| 1061 | * calc_load - given tick count, update the avenrun load estimates. |
| 1062 | * This is called while holding a write_lock on xtime_lock. |
| 1063 | */ |
| 1064 | static inline void calc_load(unsigned long ticks) |
| 1065 | { |
| 1066 | unsigned long active_tasks; /* fixed-point */ |
| 1067 | static int count = LOAD_FREQ; |
| 1068 | |
Eric Dumazet | cd7175e | 2006-12-13 00:35:45 -0800 | [diff] [blame] | 1069 | count -= ticks; |
| 1070 | if (unlikely(count < 0)) { |
| 1071 | active_tasks = count_active_tasks(); |
| 1072 | do { |
| 1073 | CALC_LOAD(avenrun[0], EXP_1, active_tasks); |
| 1074 | CALC_LOAD(avenrun[1], EXP_5, active_tasks); |
| 1075 | CALC_LOAD(avenrun[2], EXP_15, active_tasks); |
| 1076 | count += LOAD_FREQ; |
| 1077 | } while (count < 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1078 | } |
| 1079 | } |
| 1080 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1081 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1082 | * This function runs timers and the timer-tq in bottom half context. |
| 1083 | */ |
| 1084 | static void run_timer_softirq(struct softirq_action *h) |
| 1085 | { |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 1086 | struct tvec_base *base = __get_cpu_var(tvec_bases); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1087 | |
Peter Zijlstra | d3d7445 | 2008-01-25 21:08:31 +0100 | [diff] [blame] | 1088 | hrtimer_run_pending(); |
Ingo Molnar | 82f67cd | 2007-02-16 01:28:13 -0800 | [diff] [blame] | 1089 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1090 | if (time_after_eq(jiffies, base->timer_jiffies)) |
| 1091 | __run_timers(base); |
| 1092 | } |
| 1093 | |
| 1094 | /* |
| 1095 | * Called by the local, per-CPU timer interrupt on SMP. |
| 1096 | */ |
| 1097 | void run_local_timers(void) |
| 1098 | { |
Peter Zijlstra | d3d7445 | 2008-01-25 21:08:31 +0100 | [diff] [blame] | 1099 | hrtimer_run_queues(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1100 | raise_softirq(TIMER_SOFTIRQ); |
Ingo Molnar | 6687a97 | 2006-03-24 03:18:41 -0800 | [diff] [blame] | 1101 | softlockup_tick(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1102 | } |
| 1103 | |
| 1104 | /* |
| 1105 | * Called by the timer interrupt. xtime_lock must already be taken |
| 1106 | * by the timer IRQ! |
| 1107 | */ |
Atsushi Nemoto | 3171a03 | 2006-09-29 02:00:32 -0700 | [diff] [blame] | 1108 | static inline void update_times(unsigned long ticks) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1109 | { |
john stultz | ad59617 | 2006-06-26 00:25:06 -0700 | [diff] [blame] | 1110 | update_wall_time(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1111 | calc_load(ticks); |
| 1112 | } |
Thomas Gleixner | 6819457 | 2007-07-19 01:49:16 -0700 | [diff] [blame] | 1113 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1114 | /* |
| 1115 | * The 64-bit jiffies value is not atomic - you MUST NOT read it |
| 1116 | * without sampling the sequence number in xtime_lock. |
| 1117 | * jiffies is defined in the linker script... |
| 1118 | */ |
| 1119 | |
Atsushi Nemoto | 3171a03 | 2006-09-29 02:00:32 -0700 | [diff] [blame] | 1120 | void do_timer(unsigned long ticks) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1121 | { |
Atsushi Nemoto | 3171a03 | 2006-09-29 02:00:32 -0700 | [diff] [blame] | 1122 | jiffies_64 += ticks; |
| 1123 | update_times(ticks); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1124 | } |
| 1125 | |
| 1126 | #ifdef __ARCH_WANT_SYS_ALARM |
| 1127 | |
| 1128 | /* |
| 1129 | * For backwards compatibility? This can be done in libc so Alpha |
| 1130 | * and all newer ports shouldn't need it. |
| 1131 | */ |
Heiko Carstens | 58fd3aa | 2009-01-14 14:14:03 +0100 | [diff] [blame] | 1132 | SYSCALL_DEFINE1(alarm, unsigned int, seconds) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1133 | { |
Thomas Gleixner | c08b8a4 | 2006-03-25 03:06:33 -0800 | [diff] [blame] | 1134 | return alarm_setitimer(seconds); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1135 | } |
| 1136 | |
| 1137 | #endif |
| 1138 | |
| 1139 | #ifndef __alpha__ |
| 1140 | |
| 1141 | /* |
| 1142 | * The Alpha uses getxpid, getxuid, and getxgid instead. Maybe this |
| 1143 | * should be moved into arch/i386 instead? |
| 1144 | */ |
| 1145 | |
| 1146 | /** |
| 1147 | * sys_getpid - return the thread group id of the current process |
| 1148 | * |
| 1149 | * Note, despite the name, this returns the tgid not the pid. The tgid and |
| 1150 | * the pid are identical unless CLONE_THREAD was specified on clone() in |
| 1151 | * which case the tgid is the same in all threads of the same group. |
| 1152 | * |
| 1153 | * This is SMP safe as current->tgid does not change. |
| 1154 | */ |
Heiko Carstens | 58fd3aa | 2009-01-14 14:14:03 +0100 | [diff] [blame] | 1155 | SYSCALL_DEFINE0(getpid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1156 | { |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 1157 | return task_tgid_vnr(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1158 | } |
| 1159 | |
| 1160 | /* |
Kirill Korotaev | 6997a6f | 2006-08-13 23:24:23 -0700 | [diff] [blame] | 1161 | * Accessing ->real_parent is not SMP-safe, it could |
| 1162 | * change from under us. However, we can use a stale |
| 1163 | * value of ->real_parent under rcu_read_lock(), see |
| 1164 | * release_task()->call_rcu(delayed_put_task_struct). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1165 | */ |
Heiko Carstens | dbf040d | 2009-01-14 14:14:04 +0100 | [diff] [blame] | 1166 | SYSCALL_DEFINE0(getppid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1167 | { |
| 1168 | int pid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1169 | |
Kirill Korotaev | 6997a6f | 2006-08-13 23:24:23 -0700 | [diff] [blame] | 1170 | rcu_read_lock(); |
Pavel Emelyanov | 6c5f3e7 | 2008-02-08 04:19:20 -0800 | [diff] [blame] | 1171 | pid = task_tgid_vnr(current->real_parent); |
Kirill Korotaev | 6997a6f | 2006-08-13 23:24:23 -0700 | [diff] [blame] | 1172 | rcu_read_unlock(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1173 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1174 | return pid; |
| 1175 | } |
| 1176 | |
Heiko Carstens | dbf040d | 2009-01-14 14:14:04 +0100 | [diff] [blame] | 1177 | SYSCALL_DEFINE0(getuid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1178 | { |
| 1179 | /* Only we change this so SMP safe */ |
David Howells | 76aac0e | 2008-11-14 10:39:12 +1100 | [diff] [blame] | 1180 | return current_uid(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1181 | } |
| 1182 | |
Heiko Carstens | dbf040d | 2009-01-14 14:14:04 +0100 | [diff] [blame] | 1183 | SYSCALL_DEFINE0(geteuid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1184 | { |
| 1185 | /* Only we change this so SMP safe */ |
David Howells | 76aac0e | 2008-11-14 10:39:12 +1100 | [diff] [blame] | 1186 | return current_euid(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1187 | } |
| 1188 | |
Heiko Carstens | dbf040d | 2009-01-14 14:14:04 +0100 | [diff] [blame] | 1189 | SYSCALL_DEFINE0(getgid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1190 | { |
| 1191 | /* Only we change this so SMP safe */ |
David Howells | 76aac0e | 2008-11-14 10:39:12 +1100 | [diff] [blame] | 1192 | return current_gid(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1193 | } |
| 1194 | |
Heiko Carstens | dbf040d | 2009-01-14 14:14:04 +0100 | [diff] [blame] | 1195 | SYSCALL_DEFINE0(getegid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1196 | { |
| 1197 | /* Only we change this so SMP safe */ |
David Howells | 76aac0e | 2008-11-14 10:39:12 +1100 | [diff] [blame] | 1198 | return current_egid(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1199 | } |
| 1200 | |
| 1201 | #endif |
| 1202 | |
| 1203 | static void process_timeout(unsigned long __data) |
| 1204 | { |
Ingo Molnar | 36c8b58 | 2006-07-03 00:25:41 -0700 | [diff] [blame] | 1205 | wake_up_process((struct task_struct *)__data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1206 | } |
| 1207 | |
| 1208 | /** |
| 1209 | * schedule_timeout - sleep until timeout |
| 1210 | * @timeout: timeout value in jiffies |
| 1211 | * |
| 1212 | * Make the current task sleep until @timeout jiffies have |
| 1213 | * elapsed. The routine will return immediately unless |
| 1214 | * the current task state has been set (see set_current_state()). |
| 1215 | * |
| 1216 | * You can set the task state as follows - |
| 1217 | * |
| 1218 | * %TASK_UNINTERRUPTIBLE - at least @timeout jiffies are guaranteed to |
| 1219 | * pass before the routine returns. The routine will return 0 |
| 1220 | * |
| 1221 | * %TASK_INTERRUPTIBLE - the routine may return early if a signal is |
| 1222 | * delivered to the current task. In this case the remaining time |
| 1223 | * in jiffies will be returned, or 0 if the timer expired in time |
| 1224 | * |
| 1225 | * The current task state is guaranteed to be TASK_RUNNING when this |
| 1226 | * routine returns. |
| 1227 | * |
| 1228 | * Specifying a @timeout value of %MAX_SCHEDULE_TIMEOUT will schedule |
| 1229 | * the CPU away without a bound on the timeout. In this case the return |
| 1230 | * value will be %MAX_SCHEDULE_TIMEOUT. |
| 1231 | * |
| 1232 | * In all cases the return value is guaranteed to be non-negative. |
| 1233 | */ |
Harvey Harrison | 7ad5b3a | 2008-02-08 04:19:53 -0800 | [diff] [blame] | 1234 | signed long __sched schedule_timeout(signed long timeout) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1235 | { |
| 1236 | struct timer_list timer; |
| 1237 | unsigned long expire; |
| 1238 | |
| 1239 | switch (timeout) |
| 1240 | { |
| 1241 | case MAX_SCHEDULE_TIMEOUT: |
| 1242 | /* |
| 1243 | * These two special cases are useful to be comfortable |
| 1244 | * in the caller. Nothing more. We could take |
| 1245 | * MAX_SCHEDULE_TIMEOUT from one of the negative value |
| 1246 | * but I' d like to return a valid offset (>=0) to allow |
| 1247 | * the caller to do everything it want with the retval. |
| 1248 | */ |
| 1249 | schedule(); |
| 1250 | goto out; |
| 1251 | default: |
| 1252 | /* |
| 1253 | * Another bit of PARANOID. Note that the retval will be |
| 1254 | * 0 since no piece of kernel is supposed to do a check |
| 1255 | * for a negative retval of schedule_timeout() (since it |
| 1256 | * should never happens anyway). You just have the printk() |
| 1257 | * that will tell you if something is gone wrong and where. |
| 1258 | */ |
Andrew Morton | 5b149bc | 2006-12-22 01:10:14 -0800 | [diff] [blame] | 1259 | if (timeout < 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1260 | printk(KERN_ERR "schedule_timeout: wrong timeout " |
Andrew Morton | 5b149bc | 2006-12-22 01:10:14 -0800 | [diff] [blame] | 1261 | "value %lx\n", timeout); |
| 1262 | dump_stack(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1263 | current->state = TASK_RUNNING; |
| 1264 | goto out; |
| 1265 | } |
| 1266 | } |
| 1267 | |
| 1268 | expire = timeout + jiffies; |
| 1269 | |
Thomas Gleixner | c6f3a97 | 2008-04-30 00:55:03 -0700 | [diff] [blame] | 1270 | setup_timer_on_stack(&timer, process_timeout, (unsigned long)current); |
Oleg Nesterov | a8db2db | 2005-10-30 15:01:38 -0800 | [diff] [blame] | 1271 | __mod_timer(&timer, expire); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1272 | schedule(); |
| 1273 | del_singleshot_timer_sync(&timer); |
| 1274 | |
Thomas Gleixner | c6f3a97 | 2008-04-30 00:55:03 -0700 | [diff] [blame] | 1275 | /* Remove the timer from the object tracker */ |
| 1276 | destroy_timer_on_stack(&timer); |
| 1277 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1278 | timeout = expire - jiffies; |
| 1279 | |
| 1280 | out: |
| 1281 | return timeout < 0 ? 0 : timeout; |
| 1282 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1283 | EXPORT_SYMBOL(schedule_timeout); |
| 1284 | |
Andrew Morton | 8a1c175 | 2005-09-13 01:25:15 -0700 | [diff] [blame] | 1285 | /* |
| 1286 | * We can use __set_current_state() here because schedule_timeout() calls |
| 1287 | * schedule() unconditionally. |
| 1288 | */ |
Nishanth Aravamudan | 64ed93a | 2005-09-10 00:27:21 -0700 | [diff] [blame] | 1289 | signed long __sched schedule_timeout_interruptible(signed long timeout) |
| 1290 | { |
Andrew Morton | a5a0d52 | 2005-10-30 15:01:42 -0800 | [diff] [blame] | 1291 | __set_current_state(TASK_INTERRUPTIBLE); |
| 1292 | return schedule_timeout(timeout); |
Nishanth Aravamudan | 64ed93a | 2005-09-10 00:27:21 -0700 | [diff] [blame] | 1293 | } |
| 1294 | EXPORT_SYMBOL(schedule_timeout_interruptible); |
| 1295 | |
Matthew Wilcox | 294d5cc | 2007-12-06 11:59:46 -0500 | [diff] [blame] | 1296 | signed long __sched schedule_timeout_killable(signed long timeout) |
| 1297 | { |
| 1298 | __set_current_state(TASK_KILLABLE); |
| 1299 | return schedule_timeout(timeout); |
| 1300 | } |
| 1301 | EXPORT_SYMBOL(schedule_timeout_killable); |
| 1302 | |
Nishanth Aravamudan | 64ed93a | 2005-09-10 00:27:21 -0700 | [diff] [blame] | 1303 | signed long __sched schedule_timeout_uninterruptible(signed long timeout) |
| 1304 | { |
Andrew Morton | a5a0d52 | 2005-10-30 15:01:42 -0800 | [diff] [blame] | 1305 | __set_current_state(TASK_UNINTERRUPTIBLE); |
| 1306 | return schedule_timeout(timeout); |
Nishanth Aravamudan | 64ed93a | 2005-09-10 00:27:21 -0700 | [diff] [blame] | 1307 | } |
| 1308 | EXPORT_SYMBOL(schedule_timeout_uninterruptible); |
| 1309 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1310 | /* Thread ID - the internal kernel "pid" */ |
Heiko Carstens | 58fd3aa | 2009-01-14 14:14:03 +0100 | [diff] [blame] | 1311 | SYSCALL_DEFINE0(gettid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1312 | { |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 1313 | return task_pid_vnr(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1314 | } |
| 1315 | |
Rolf Eike Beer | 2aae4a1 | 2006-09-29 01:59:46 -0700 | [diff] [blame] | 1316 | /** |
Kyle McMartin | d4d23ad | 2007-02-10 01:46:00 -0800 | [diff] [blame] | 1317 | * do_sysinfo - fill in sysinfo struct |
Rolf Eike Beer | 2aae4a1 | 2006-09-29 01:59:46 -0700 | [diff] [blame] | 1318 | * @info: pointer to buffer to fill |
Thomas Gleixner | 6819457 | 2007-07-19 01:49:16 -0700 | [diff] [blame] | 1319 | */ |
Kyle McMartin | d4d23ad | 2007-02-10 01:46:00 -0800 | [diff] [blame] | 1320 | int do_sysinfo(struct sysinfo *info) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1321 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1322 | unsigned long mem_total, sav_total; |
| 1323 | unsigned int mem_unit, bitcount; |
| 1324 | unsigned long seq; |
| 1325 | |
Kyle McMartin | d4d23ad | 2007-02-10 01:46:00 -0800 | [diff] [blame] | 1326 | memset(info, 0, sizeof(struct sysinfo)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1327 | |
| 1328 | do { |
| 1329 | struct timespec tp; |
| 1330 | seq = read_seqbegin(&xtime_lock); |
| 1331 | |
| 1332 | /* |
| 1333 | * This is annoying. The below is the same thing |
| 1334 | * posix_get_clock_monotonic() does, but it wants to |
| 1335 | * take the lock which we want to cover the loads stuff |
| 1336 | * too. |
| 1337 | */ |
| 1338 | |
| 1339 | getnstimeofday(&tp); |
| 1340 | tp.tv_sec += wall_to_monotonic.tv_sec; |
| 1341 | tp.tv_nsec += wall_to_monotonic.tv_nsec; |
Tomas Janousek | d621414 | 2007-07-15 23:39:42 -0700 | [diff] [blame] | 1342 | monotonic_to_bootbased(&tp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1343 | if (tp.tv_nsec - NSEC_PER_SEC >= 0) { |
| 1344 | tp.tv_nsec = tp.tv_nsec - NSEC_PER_SEC; |
| 1345 | tp.tv_sec++; |
| 1346 | } |
Kyle McMartin | d4d23ad | 2007-02-10 01:46:00 -0800 | [diff] [blame] | 1347 | info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1348 | |
Kyle McMartin | d4d23ad | 2007-02-10 01:46:00 -0800 | [diff] [blame] | 1349 | info->loads[0] = avenrun[0] << (SI_LOAD_SHIFT - FSHIFT); |
| 1350 | info->loads[1] = avenrun[1] << (SI_LOAD_SHIFT - FSHIFT); |
| 1351 | info->loads[2] = avenrun[2] << (SI_LOAD_SHIFT - FSHIFT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1352 | |
Kyle McMartin | d4d23ad | 2007-02-10 01:46:00 -0800 | [diff] [blame] | 1353 | info->procs = nr_threads; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1354 | } while (read_seqretry(&xtime_lock, seq)); |
| 1355 | |
Kyle McMartin | d4d23ad | 2007-02-10 01:46:00 -0800 | [diff] [blame] | 1356 | si_meminfo(info); |
| 1357 | si_swapinfo(info); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1358 | |
| 1359 | /* |
| 1360 | * If the sum of all the available memory (i.e. ram + swap) |
| 1361 | * is less than can be stored in a 32 bit unsigned long then |
| 1362 | * we can be binary compatible with 2.2.x kernels. If not, |
| 1363 | * well, in that case 2.2.x was broken anyways... |
| 1364 | * |
| 1365 | * -Erik Andersen <andersee@debian.org> |
| 1366 | */ |
| 1367 | |
Kyle McMartin | d4d23ad | 2007-02-10 01:46:00 -0800 | [diff] [blame] | 1368 | mem_total = info->totalram + info->totalswap; |
| 1369 | if (mem_total < info->totalram || mem_total < info->totalswap) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1370 | goto out; |
| 1371 | bitcount = 0; |
Kyle McMartin | d4d23ad | 2007-02-10 01:46:00 -0800 | [diff] [blame] | 1372 | mem_unit = info->mem_unit; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1373 | while (mem_unit > 1) { |
| 1374 | bitcount++; |
| 1375 | mem_unit >>= 1; |
| 1376 | sav_total = mem_total; |
| 1377 | mem_total <<= 1; |
| 1378 | if (mem_total < sav_total) |
| 1379 | goto out; |
| 1380 | } |
| 1381 | |
| 1382 | /* |
| 1383 | * If mem_total did not overflow, multiply all memory values by |
Kyle McMartin | d4d23ad | 2007-02-10 01:46:00 -0800 | [diff] [blame] | 1384 | * info->mem_unit and set it to 1. This leaves things compatible |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1385 | * with 2.2.x, and also retains compatibility with earlier 2.4.x |
| 1386 | * kernels... |
| 1387 | */ |
| 1388 | |
Kyle McMartin | d4d23ad | 2007-02-10 01:46:00 -0800 | [diff] [blame] | 1389 | info->mem_unit = 1; |
| 1390 | info->totalram <<= bitcount; |
| 1391 | info->freeram <<= bitcount; |
| 1392 | info->sharedram <<= bitcount; |
| 1393 | info->bufferram <<= bitcount; |
| 1394 | info->totalswap <<= bitcount; |
| 1395 | info->freeswap <<= bitcount; |
| 1396 | info->totalhigh <<= bitcount; |
| 1397 | info->freehigh <<= bitcount; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1398 | |
Kyle McMartin | d4d23ad | 2007-02-10 01:46:00 -0800 | [diff] [blame] | 1399 | out: |
| 1400 | return 0; |
| 1401 | } |
| 1402 | |
Heiko Carstens | 1e7bfb2 | 2009-01-14 14:14:29 +0100 | [diff] [blame] | 1403 | SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info) |
Kyle McMartin | d4d23ad | 2007-02-10 01:46:00 -0800 | [diff] [blame] | 1404 | { |
| 1405 | struct sysinfo val; |
| 1406 | |
| 1407 | do_sysinfo(&val); |
| 1408 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1409 | if (copy_to_user(info, &val, sizeof(struct sysinfo))) |
| 1410 | return -EFAULT; |
| 1411 | |
| 1412 | return 0; |
| 1413 | } |
| 1414 | |
Adrian Bunk | b4be625 | 2007-12-18 18:05:58 +0100 | [diff] [blame] | 1415 | static int __cpuinit init_timers_cpu(int cpu) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1416 | { |
| 1417 | int j; |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 1418 | struct tvec_base *base; |
Adrian Bunk | b4be625 | 2007-12-18 18:05:58 +0100 | [diff] [blame] | 1419 | static char __cpuinitdata tvec_base_done[NR_CPUS]; |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 1420 | |
Andrew Morton | ba6edfc | 2006-04-10 22:53:58 -0700 | [diff] [blame] | 1421 | if (!tvec_base_done[cpu]) { |
Jan Beulich | a4a6198 | 2006-03-24 03:15:54 -0800 | [diff] [blame] | 1422 | static char boot_done; |
| 1423 | |
Jan Beulich | a4a6198 | 2006-03-24 03:15:54 -0800 | [diff] [blame] | 1424 | if (boot_done) { |
Andrew Morton | ba6edfc | 2006-04-10 22:53:58 -0700 | [diff] [blame] | 1425 | /* |
| 1426 | * The APs use this path later in boot |
| 1427 | */ |
Christoph Lameter | 94f6030 | 2007-07-17 04:03:29 -0700 | [diff] [blame] | 1428 | base = kmalloc_node(sizeof(*base), |
| 1429 | GFP_KERNEL | __GFP_ZERO, |
Jan Beulich | a4a6198 | 2006-03-24 03:15:54 -0800 | [diff] [blame] | 1430 | cpu_to_node(cpu)); |
| 1431 | if (!base) |
| 1432 | return -ENOMEM; |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 1433 | |
| 1434 | /* Make sure that tvec_base is 2 byte aligned */ |
| 1435 | if (tbase_get_deferrable(base)) { |
| 1436 | WARN_ON(1); |
| 1437 | kfree(base); |
| 1438 | return -ENOMEM; |
| 1439 | } |
Andrew Morton | ba6edfc | 2006-04-10 22:53:58 -0700 | [diff] [blame] | 1440 | per_cpu(tvec_bases, cpu) = base; |
Jan Beulich | a4a6198 | 2006-03-24 03:15:54 -0800 | [diff] [blame] | 1441 | } else { |
Andrew Morton | ba6edfc | 2006-04-10 22:53:58 -0700 | [diff] [blame] | 1442 | /* |
| 1443 | * This is for the boot CPU - we use compile-time |
| 1444 | * static initialisation because per-cpu memory isn't |
| 1445 | * ready yet and because the memory allocators are not |
| 1446 | * initialised either. |
| 1447 | */ |
Jan Beulich | a4a6198 | 2006-03-24 03:15:54 -0800 | [diff] [blame] | 1448 | boot_done = 1; |
Andrew Morton | ba6edfc | 2006-04-10 22:53:58 -0700 | [diff] [blame] | 1449 | base = &boot_tvec_bases; |
Jan Beulich | a4a6198 | 2006-03-24 03:15:54 -0800 | [diff] [blame] | 1450 | } |
Andrew Morton | ba6edfc | 2006-04-10 22:53:58 -0700 | [diff] [blame] | 1451 | tvec_base_done[cpu] = 1; |
| 1452 | } else { |
| 1453 | base = per_cpu(tvec_bases, cpu); |
Jan Beulich | a4a6198 | 2006-03-24 03:15:54 -0800 | [diff] [blame] | 1454 | } |
Andrew Morton | ba6edfc | 2006-04-10 22:53:58 -0700 | [diff] [blame] | 1455 | |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 1456 | spin_lock_init(&base->lock); |
Ingo Molnar | d730e88 | 2006-07-03 00:25:10 -0700 | [diff] [blame] | 1457 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1458 | for (j = 0; j < TVN_SIZE; j++) { |
| 1459 | INIT_LIST_HEAD(base->tv5.vec + j); |
| 1460 | INIT_LIST_HEAD(base->tv4.vec + j); |
| 1461 | INIT_LIST_HEAD(base->tv3.vec + j); |
| 1462 | INIT_LIST_HEAD(base->tv2.vec + j); |
| 1463 | } |
| 1464 | for (j = 0; j < TVR_SIZE; j++) |
| 1465 | INIT_LIST_HEAD(base->tv1.vec + j); |
| 1466 | |
| 1467 | base->timer_jiffies = jiffies; |
Jan Beulich | a4a6198 | 2006-03-24 03:15:54 -0800 | [diff] [blame] | 1468 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1469 | } |
| 1470 | |
| 1471 | #ifdef CONFIG_HOTPLUG_CPU |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 1472 | static void migrate_timer_list(struct tvec_base *new_base, struct list_head *head) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1473 | { |
| 1474 | struct timer_list *timer; |
| 1475 | |
| 1476 | while (!list_empty(head)) { |
Pavel Emelianov | b5e6181 | 2007-05-08 00:30:19 -0700 | [diff] [blame] | 1477 | timer = list_first_entry(head, struct timer_list, entry); |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 1478 | detach_timer(timer, 0); |
Venki Pallipadi | 6e453a6 | 2007-05-08 00:27:44 -0700 | [diff] [blame] | 1479 | timer_set_base(timer, new_base); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1480 | internal_add_timer(new_base, timer); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1481 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1482 | } |
| 1483 | |
Randy Dunlap | 48ccf3d | 2008-01-21 17:18:25 -0800 | [diff] [blame] | 1484 | static void __cpuinit migrate_timers(int cpu) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1485 | { |
Pavel Machek | a6fa8e5 | 2008-01-30 13:30:00 +0100 | [diff] [blame] | 1486 | struct tvec_base *old_base; |
| 1487 | struct tvec_base *new_base; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1488 | int i; |
| 1489 | |
| 1490 | BUG_ON(cpu_online(cpu)); |
Jan Beulich | a4a6198 | 2006-03-24 03:15:54 -0800 | [diff] [blame] | 1491 | old_base = per_cpu(tvec_bases, cpu); |
| 1492 | new_base = get_cpu_var(tvec_bases); |
Oleg Nesterov | d82f0b0 | 2008-08-20 16:46:04 -0700 | [diff] [blame] | 1493 | /* |
| 1494 | * The caller is globally serialized and nobody else |
| 1495 | * takes two locks at once, deadlock is not possible. |
| 1496 | */ |
| 1497 | spin_lock_irq(&new_base->lock); |
Oleg Nesterov | 0d18040 | 2008-04-04 20:54:10 +0200 | [diff] [blame] | 1498 | spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1499 | |
Oleg Nesterov | 3691c51 | 2006-03-31 02:30:30 -0800 | [diff] [blame] | 1500 | BUG_ON(old_base->running_timer); |
| 1501 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1502 | for (i = 0; i < TVR_SIZE; i++) |
Oleg Nesterov | 55c888d | 2005-06-23 00:08:56 -0700 | [diff] [blame] | 1503 | migrate_timer_list(new_base, old_base->tv1.vec + i); |
| 1504 | for (i = 0; i < TVN_SIZE; i++) { |
| 1505 | migrate_timer_list(new_base, old_base->tv2.vec + i); |
| 1506 | migrate_timer_list(new_base, old_base->tv3.vec + i); |
| 1507 | migrate_timer_list(new_base, old_base->tv4.vec + i); |
| 1508 | migrate_timer_list(new_base, old_base->tv5.vec + i); |
| 1509 | } |
| 1510 | |
Oleg Nesterov | 0d18040 | 2008-04-04 20:54:10 +0200 | [diff] [blame] | 1511 | spin_unlock(&old_base->lock); |
Oleg Nesterov | d82f0b0 | 2008-08-20 16:46:04 -0700 | [diff] [blame] | 1512 | spin_unlock_irq(&new_base->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1513 | put_cpu_var(tvec_bases); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1514 | } |
| 1515 | #endif /* CONFIG_HOTPLUG_CPU */ |
| 1516 | |
Chandra Seetharaman | 8c78f30 | 2006-07-30 03:03:35 -0700 | [diff] [blame] | 1517 | static int __cpuinit timer_cpu_notify(struct notifier_block *self, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1518 | unsigned long action, void *hcpu) |
| 1519 | { |
| 1520 | long cpu = (long)hcpu; |
| 1521 | switch(action) { |
| 1522 | case CPU_UP_PREPARE: |
Rafael J. Wysocki | 8bb7844 | 2007-05-09 02:35:10 -0700 | [diff] [blame] | 1523 | case CPU_UP_PREPARE_FROZEN: |
Jan Beulich | a4a6198 | 2006-03-24 03:15:54 -0800 | [diff] [blame] | 1524 | if (init_timers_cpu(cpu) < 0) |
| 1525 | return NOTIFY_BAD; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1526 | break; |
| 1527 | #ifdef CONFIG_HOTPLUG_CPU |
| 1528 | case CPU_DEAD: |
Rafael J. Wysocki | 8bb7844 | 2007-05-09 02:35:10 -0700 | [diff] [blame] | 1529 | case CPU_DEAD_FROZEN: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1530 | migrate_timers(cpu); |
| 1531 | break; |
| 1532 | #endif |
| 1533 | default: |
| 1534 | break; |
| 1535 | } |
| 1536 | return NOTIFY_OK; |
| 1537 | } |
| 1538 | |
Chandra Seetharaman | 8c78f30 | 2006-07-30 03:03:35 -0700 | [diff] [blame] | 1539 | static struct notifier_block __cpuinitdata timers_nb = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1540 | .notifier_call = timer_cpu_notify, |
| 1541 | }; |
| 1542 | |
| 1543 | |
| 1544 | void __init init_timers(void) |
| 1545 | { |
Akinobu Mita | 07dccf3 | 2006-09-29 02:00:22 -0700 | [diff] [blame] | 1546 | int err = timer_cpu_notify(&timers_nb, (unsigned long)CPU_UP_PREPARE, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1547 | (void *)(long)smp_processor_id()); |
Akinobu Mita | 07dccf3 | 2006-09-29 02:00:22 -0700 | [diff] [blame] | 1548 | |
Ingo Molnar | 82f67cd | 2007-02-16 01:28:13 -0800 | [diff] [blame] | 1549 | init_timer_stats(); |
| 1550 | |
Akinobu Mita | 07dccf3 | 2006-09-29 02:00:22 -0700 | [diff] [blame] | 1551 | BUG_ON(err == NOTIFY_BAD); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1552 | register_cpu_notifier(&timers_nb); |
Carlos R. Mafra | 962cf36 | 2008-05-15 11:15:37 -0300 | [diff] [blame] | 1553 | open_softirq(TIMER_SOFTIRQ, run_timer_softirq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1554 | } |
| 1555 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1556 | /** |
| 1557 | * msleep - sleep safely even with waitqueue interruptions |
| 1558 | * @msecs: Time in milliseconds to sleep for |
| 1559 | */ |
| 1560 | void msleep(unsigned int msecs) |
| 1561 | { |
| 1562 | unsigned long timeout = msecs_to_jiffies(msecs) + 1; |
| 1563 | |
Nishanth Aravamudan | 75bcc8c | 2005-09-10 00:27:24 -0700 | [diff] [blame] | 1564 | while (timeout) |
| 1565 | timeout = schedule_timeout_uninterruptible(timeout); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1566 | } |
| 1567 | |
| 1568 | EXPORT_SYMBOL(msleep); |
| 1569 | |
| 1570 | /** |
Domen Puncer | 96ec3ef | 2005-06-25 14:58:43 -0700 | [diff] [blame] | 1571 | * msleep_interruptible - sleep waiting for signals |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1572 | * @msecs: Time in milliseconds to sleep for |
| 1573 | */ |
| 1574 | unsigned long msleep_interruptible(unsigned int msecs) |
| 1575 | { |
| 1576 | unsigned long timeout = msecs_to_jiffies(msecs) + 1; |
| 1577 | |
Nishanth Aravamudan | 75bcc8c | 2005-09-10 00:27:24 -0700 | [diff] [blame] | 1578 | while (timeout && !signal_pending(current)) |
| 1579 | timeout = schedule_timeout_interruptible(timeout); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1580 | return jiffies_to_msecs(timeout); |
| 1581 | } |
| 1582 | |
| 1583 | EXPORT_SYMBOL(msleep_interruptible); |