Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | #ifndef __ASM_SPINLOCK_H |
| 2 | #define __ASM_SPINLOCK_H |
Arnd Bergmann | 88ced03 | 2005-12-16 22:43:46 +0100 | [diff] [blame] | 3 | #ifdef __KERNEL__ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | |
| 5 | /* |
| 6 | * Simple spin lock operations. |
| 7 | * |
| 8 | * Copyright (C) 2001-2004 Paul Mackerras <paulus@au.ibm.com>, IBM |
| 9 | * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM |
| 10 | * Copyright (C) 2002 Dave Engebretsen <engebret@us.ibm.com>, IBM |
| 11 | * Rework to support virtual processors |
| 12 | * |
| 13 | * Type of int is used as a full 64b word is not necessary. |
| 14 | * |
| 15 | * This program is free software; you can redistribute it and/or |
| 16 | * modify it under the terms of the GNU General Public License |
| 17 | * as published by the Free Software Foundation; either version |
| 18 | * 2 of the License, or (at your option) any later version. |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 19 | * |
| 20 | * (the type definitions are in asm/spinlock_types.h) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | */ |
Benjamin Herrenschmidt | 945feb1 | 2008-04-17 14:35:01 +1000 | [diff] [blame] | 22 | #include <linux/irqflags.h> |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 23 | #ifdef CONFIG_PPC64 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | #include <asm/paca.h> |
| 25 | #include <asm/hvcall.h> |
Kelly Daly | 1da4403 | 2005-11-01 16:59:20 +1100 | [diff] [blame] | 26 | #include <asm/iseries/hv_call.h> |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 27 | #endif |
| 28 | #include <asm/asm-compat.h> |
| 29 | #include <asm/synch.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | |
Thomas Gleixner | 0199c4e | 2009-12-02 20:01:25 +0100 | [diff] [blame] | 31 | #define arch_spin_is_locked(x) ((x)->slock != 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 33 | #ifdef CONFIG_PPC64 |
| 34 | /* use 0x800000yy when locked, where yy == CPU number */ |
| 35 | #define LOCK_TOKEN (*(u32 *)(&get_paca()->lock_token)) |
| 36 | #else |
| 37 | #define LOCK_TOKEN 1 |
| 38 | #endif |
| 39 | |
Paul Mackerras | f007cac | 2006-09-13 22:08:26 +1000 | [diff] [blame] | 40 | #if defined(CONFIG_PPC64) && defined(CONFIG_SMP) |
| 41 | #define CLEAR_IO_SYNC (get_paca()->io_sync = 0) |
| 42 | #define SYNC_IO do { \ |
| 43 | if (unlikely(get_paca()->io_sync)) { \ |
| 44 | mb(); \ |
| 45 | get_paca()->io_sync = 0; \ |
| 46 | } \ |
| 47 | } while (0) |
| 48 | #else |
| 49 | #define CLEAR_IO_SYNC |
| 50 | #define SYNC_IO |
| 51 | #endif |
| 52 | |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 53 | /* |
| 54 | * This returns the old value in the lock, so we succeeded |
| 55 | * in getting the lock if the return value is 0. |
| 56 | */ |
Thomas Gleixner | 0199c4e | 2009-12-02 20:01:25 +0100 | [diff] [blame] | 57 | static inline unsigned long __arch_spin_trylock(arch_spinlock_t *lock) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | { |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 59 | unsigned long tmp, token; |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 60 | |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 61 | token = LOCK_TOKEN; |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 62 | __asm__ __volatile__( |
Anton Blanchard | 144b9c1 | 2006-01-13 15:37:17 +1100 | [diff] [blame] | 63 | "1: lwarx %0,0,%2\n\ |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 64 | cmpwi 0,%0,0\n\ |
| 65 | bne- 2f\n\ |
| 66 | stwcx. %1,0,%2\n\ |
| 67 | bne- 1b\n\ |
| 68 | isync\n\ |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 69 | 2:" : "=&r" (tmp) |
| 70 | : "r" (token), "r" (&lock->slock) |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 71 | : "cr0", "memory"); |
| 72 | |
| 73 | return tmp; |
| 74 | } |
| 75 | |
Thomas Gleixner | 0199c4e | 2009-12-02 20:01:25 +0100 | [diff] [blame] | 76 | static inline int arch_spin_trylock(arch_spinlock_t *lock) |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 77 | { |
Paul Mackerras | f007cac | 2006-09-13 22:08:26 +1000 | [diff] [blame] | 78 | CLEAR_IO_SYNC; |
Thomas Gleixner | 0199c4e | 2009-12-02 20:01:25 +0100 | [diff] [blame] | 79 | return __arch_spin_trylock(lock) == 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | } |
| 81 | |
| 82 | /* |
| 83 | * On a system with shared processors (that is, where a physical |
| 84 | * processor is multiplexed between several virtual processors), |
| 85 | * there is no point spinning on a lock if the holder of the lock |
| 86 | * isn't currently scheduled on a physical processor. Instead |
| 87 | * we detect this situation and ask the hypervisor to give the |
| 88 | * rest of our timeslice to the lock holder. |
| 89 | * |
| 90 | * So that we can tell which virtual processor is holding a lock, |
| 91 | * we put 0x80000000 | smp_processor_id() in the lock when it is |
| 92 | * held. Conveniently, we have a word in the paca that holds this |
| 93 | * value. |
| 94 | */ |
| 95 | |
| 96 | #if defined(CONFIG_PPC_SPLPAR) || defined(CONFIG_PPC_ISERIES) |
| 97 | /* We only yield to the hypervisor if we are in shared processor mode */ |
David Gibson | 3356bb9f7 | 2006-01-13 10:26:42 +1100 | [diff] [blame] | 98 | #define SHARED_PROCESSOR (get_lppaca()->shared_proc) |
Thomas Gleixner | 445c895 | 2009-12-02 19:49:50 +0100 | [diff] [blame] | 99 | extern void __spin_yield(arch_spinlock_t *lock); |
Thomas Gleixner | fb3a6bb | 2009-12-03 20:01:19 +0100 | [diff] [blame] | 100 | extern void __rw_yield(arch_rwlock_t *lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | #else /* SPLPAR || ISERIES */ |
| 102 | #define __spin_yield(x) barrier() |
| 103 | #define __rw_yield(x) barrier() |
| 104 | #define SHARED_PROCESSOR 0 |
| 105 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | |
Thomas Gleixner | 0199c4e | 2009-12-02 20:01:25 +0100 | [diff] [blame] | 107 | static inline void arch_spin_lock(arch_spinlock_t *lock) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 108 | { |
Paul Mackerras | f007cac | 2006-09-13 22:08:26 +1000 | [diff] [blame] | 109 | CLEAR_IO_SYNC; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 110 | while (1) { |
Thomas Gleixner | 0199c4e | 2009-12-02 20:01:25 +0100 | [diff] [blame] | 111 | if (likely(__arch_spin_trylock(lock) == 0)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | break; |
| 113 | do { |
| 114 | HMT_low(); |
| 115 | if (SHARED_PROCESSOR) |
| 116 | __spin_yield(lock); |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 117 | } while (unlikely(lock->slock != 0)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 118 | HMT_medium(); |
| 119 | } |
| 120 | } |
| 121 | |
Bart Van Assche | 89b5810 | 2008-06-28 16:51:35 +1000 | [diff] [blame] | 122 | static inline |
Thomas Gleixner | 0199c4e | 2009-12-02 20:01:25 +0100 | [diff] [blame] | 123 | void arch_spin_lock_flags(arch_spinlock_t *lock, unsigned long flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 124 | { |
| 125 | unsigned long flags_dis; |
| 126 | |
Paul Mackerras | f007cac | 2006-09-13 22:08:26 +1000 | [diff] [blame] | 127 | CLEAR_IO_SYNC; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 128 | while (1) { |
Thomas Gleixner | 0199c4e | 2009-12-02 20:01:25 +0100 | [diff] [blame] | 129 | if (likely(__arch_spin_trylock(lock) == 0)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | break; |
| 131 | local_save_flags(flags_dis); |
| 132 | local_irq_restore(flags); |
| 133 | do { |
| 134 | HMT_low(); |
| 135 | if (SHARED_PROCESSOR) |
| 136 | __spin_yield(lock); |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 137 | } while (unlikely(lock->slock != 0)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 138 | HMT_medium(); |
| 139 | local_irq_restore(flags_dis); |
| 140 | } |
| 141 | } |
| 142 | |
Thomas Gleixner | 0199c4e | 2009-12-02 20:01:25 +0100 | [diff] [blame] | 143 | static inline void arch_spin_unlock(arch_spinlock_t *lock) |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 144 | { |
Paul Mackerras | f007cac | 2006-09-13 22:08:26 +1000 | [diff] [blame] | 145 | SYNC_IO; |
Thomas Gleixner | 0199c4e | 2009-12-02 20:01:25 +0100 | [diff] [blame] | 146 | __asm__ __volatile__("# arch_spin_unlock\n\t" |
Anton Blanchard | 144b9c1 | 2006-01-13 15:37:17 +1100 | [diff] [blame] | 147 | LWSYNC_ON_SMP: : :"memory"); |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 148 | lock->slock = 0; |
| 149 | } |
| 150 | |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 151 | #ifdef CONFIG_PPC64 |
Thomas Gleixner | 0199c4e | 2009-12-02 20:01:25 +0100 | [diff] [blame] | 152 | extern void arch_spin_unlock_wait(arch_spinlock_t *lock); |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 153 | #else |
Thomas Gleixner | 0199c4e | 2009-12-02 20:01:25 +0100 | [diff] [blame] | 154 | #define arch_spin_unlock_wait(lock) \ |
| 155 | do { while (arch_spin_is_locked(lock)) cpu_relax(); } while (0) |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 156 | #endif |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 157 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | /* |
| 159 | * Read-write spinlocks, allowing multiple readers |
| 160 | * but only one writer. |
| 161 | * |
| 162 | * NOTE! it is quite common to have readers in interrupts |
| 163 | * but no interrupt writers. For those circumstances we |
| 164 | * can "mix" irq-safe locks - any writer needs to get a |
| 165 | * irq-safe write-lock, but readers can get non-irqsafe |
| 166 | * read-locks. |
| 167 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 169 | #define arch_read_can_lock(rw) ((rw)->lock >= 0) |
| 170 | #define arch_write_can_lock(rw) (!(rw)->lock) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 172 | #ifdef CONFIG_PPC64 |
| 173 | #define __DO_SIGN_EXTEND "extsw %0,%0\n" |
| 174 | #define WRLOCK_TOKEN LOCK_TOKEN /* it's negative */ |
| 175 | #else |
| 176 | #define __DO_SIGN_EXTEND |
| 177 | #define WRLOCK_TOKEN (-1) |
| 178 | #endif |
| 179 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | /* |
| 181 | * This returns the old value in the lock + 1, |
| 182 | * so we got a read lock if the return value is > 0. |
| 183 | */ |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 184 | static inline long __arch_read_trylock(arch_rwlock_t *rw) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | { |
| 186 | long tmp; |
| 187 | |
| 188 | __asm__ __volatile__( |
Anton Blanchard | 144b9c1 | 2006-01-13 15:37:17 +1100 | [diff] [blame] | 189 | "1: lwarx %0,0,%1\n" |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 190 | __DO_SIGN_EXTEND |
| 191 | " addic. %0,%0,1\n\ |
| 192 | ble- 2f\n" |
| 193 | PPC405_ERR77(0,%1) |
| 194 | " stwcx. %0,0,%1\n\ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 195 | bne- 1b\n\ |
| 196 | isync\n\ |
| 197 | 2:" : "=&r" (tmp) |
| 198 | : "r" (&rw->lock) |
| 199 | : "cr0", "xer", "memory"); |
| 200 | |
| 201 | return tmp; |
| 202 | } |
| 203 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 204 | /* |
| 205 | * This returns the old value in the lock, |
| 206 | * so we got the write lock if the return value is 0. |
| 207 | */ |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 208 | static inline long __arch_write_trylock(arch_rwlock_t *rw) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 209 | { |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 210 | long tmp, token; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 211 | |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 212 | token = WRLOCK_TOKEN; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | __asm__ __volatile__( |
Anton Blanchard | 144b9c1 | 2006-01-13 15:37:17 +1100 | [diff] [blame] | 214 | "1: lwarx %0,0,%2\n\ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 215 | cmpwi 0,%0,0\n\ |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 216 | bne- 2f\n" |
| 217 | PPC405_ERR77(0,%1) |
| 218 | " stwcx. %1,0,%2\n\ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | bne- 1b\n\ |
| 220 | isync\n\ |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 221 | 2:" : "=&r" (tmp) |
| 222 | : "r" (token), "r" (&rw->lock) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | : "cr0", "memory"); |
| 224 | |
| 225 | return tmp; |
| 226 | } |
| 227 | |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 228 | static inline void arch_read_lock(arch_rwlock_t *rw) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 229 | { |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 230 | while (1) { |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 231 | if (likely(__arch_read_trylock(rw) > 0)) |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 232 | break; |
| 233 | do { |
| 234 | HMT_low(); |
| 235 | if (SHARED_PROCESSOR) |
| 236 | __rw_yield(rw); |
| 237 | } while (unlikely(rw->lock < 0)); |
| 238 | HMT_medium(); |
| 239 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 240 | } |
| 241 | |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 242 | static inline void arch_write_lock(arch_rwlock_t *rw) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 243 | { |
| 244 | while (1) { |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 245 | if (likely(__arch_write_trylock(rw) == 0)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | break; |
| 247 | do { |
| 248 | HMT_low(); |
| 249 | if (SHARED_PROCESSOR) |
| 250 | __rw_yield(rw); |
Jake Moilanen | d637413 | 2005-05-01 08:58:47 -0700 | [diff] [blame] | 251 | } while (unlikely(rw->lock != 0)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | HMT_medium(); |
| 253 | } |
| 254 | } |
| 255 | |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 256 | static inline int arch_read_trylock(arch_rwlock_t *rw) |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 257 | { |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 258 | return __arch_read_trylock(rw) > 0; |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 259 | } |
| 260 | |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 261 | static inline int arch_write_trylock(arch_rwlock_t *rw) |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 262 | { |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 263 | return __arch_write_trylock(rw) == 0; |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 264 | } |
| 265 | |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 266 | static inline void arch_read_unlock(arch_rwlock_t *rw) |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 267 | { |
| 268 | long tmp; |
| 269 | |
| 270 | __asm__ __volatile__( |
Anton Blanchard | 144b9c1 | 2006-01-13 15:37:17 +1100 | [diff] [blame] | 271 | "# read_unlock\n\t" |
| 272 | LWSYNC_ON_SMP |
| 273 | "1: lwarx %0,0,%1\n\ |
Paul Mackerras | 0212ddd | 2005-11-19 20:50:46 +1100 | [diff] [blame] | 274 | addic %0,%0,-1\n" |
| 275 | PPC405_ERR77(0,%1) |
| 276 | " stwcx. %0,0,%1\n\ |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 277 | bne- 1b" |
| 278 | : "=&r"(tmp) |
| 279 | : "r"(&rw->lock) |
Paul Mackerras | efc3624 | 2008-11-05 18:39:27 +0000 | [diff] [blame] | 280 | : "cr0", "xer", "memory"); |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 281 | } |
| 282 | |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 283 | static inline void arch_write_unlock(arch_rwlock_t *rw) |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 284 | { |
Anton Blanchard | 144b9c1 | 2006-01-13 15:37:17 +1100 | [diff] [blame] | 285 | __asm__ __volatile__("# write_unlock\n\t" |
| 286 | LWSYNC_ON_SMP: : :"memory"); |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 287 | rw->lock = 0; |
| 288 | } |
| 289 | |
Thomas Gleixner | e593194 | 2009-12-03 20:08:46 +0100 | [diff] [blame] | 290 | #define arch_read_lock_flags(lock, flags) arch_read_lock(lock) |
| 291 | #define arch_write_lock_flags(lock, flags) arch_write_lock(lock) |
Robin Holt | f5f7eac | 2009-04-02 16:59:46 -0700 | [diff] [blame] | 292 | |
Thomas Gleixner | 0199c4e | 2009-12-02 20:01:25 +0100 | [diff] [blame] | 293 | #define arch_spin_relax(lock) __spin_yield(lock) |
| 294 | #define arch_read_relax(lock) __rw_yield(lock) |
| 295 | #define arch_write_relax(lock) __rw_yield(lock) |
Martin Schwidefsky | ef6edc9 | 2006-09-30 23:27:43 -0700 | [diff] [blame] | 296 | |
Arnd Bergmann | 88ced03 | 2005-12-16 22:43:46 +0100 | [diff] [blame] | 297 | #endif /* __KERNEL__ */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | #endif /* __ASM_SPINLOCK_H */ |