Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | #ifndef _S390_RWSEM_H |
| 2 | #define _S390_RWSEM_H |
| 3 | |
| 4 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 5 | * S390 version |
Heiko Carstens | a53c8fa | 2012-07-20 11:15:04 +0200 | [diff] [blame] | 6 | * Copyright IBM Corp. 2002 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 7 | * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) |
| 8 | * |
| 9 | * Based on asm-alpha/semaphore.h and asm-i386/rwsem.h |
| 10 | */ |
| 11 | |
| 12 | /* |
| 13 | * |
| 14 | * The MSW of the count is the negated number of active writers and waiting |
| 15 | * lockers, and the LSW is the total number of active locks |
| 16 | * |
| 17 | * The lock count is initialized to 0 (no active and no waiting lockers). |
| 18 | * |
| 19 | * When a writer subtracts WRITE_BIAS, it'll get 0xffff0001 for the case of an |
| 20 | * uncontended lock. This can be determined because XADD returns the old value. |
| 21 | * Readers increment by 1 and see a positive value when uncontended, negative |
| 22 | * if there are writers (and maybe) readers waiting (in which case it goes to |
| 23 | * sleep). |
| 24 | * |
| 25 | * The value of WAITING_BIAS supports up to 32766 waiting processes. This can |
| 26 | * be extended to 65534 by manually checking the whole MSW rather than relying |
| 27 | * on the S flag. |
| 28 | * |
| 29 | * The value of ACTIVE_BIAS supports up to 65535 active processes. |
| 30 | * |
| 31 | * This should be totally fair - if anything is waiting, a process that wants a |
| 32 | * lock will go to the back of the queue. When the currently active lock is |
| 33 | * released, if there's a writer at the front of the queue, then that and only |
| 34 | * that will be woken up; if there's a bunch of consequtive readers at the |
| 35 | * front, then they'll all be woken up, but no other readers will be. |
| 36 | */ |
| 37 | |
| 38 | #ifndef _LINUX_RWSEM_H |
| 39 | #error "please don't include asm/rwsem.h directly, use linux/rwsem.h instead" |
| 40 | #endif |
| 41 | |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 42 | #ifndef CONFIG_64BIT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | #define RWSEM_UNLOCKED_VALUE 0x00000000 |
| 44 | #define RWSEM_ACTIVE_BIAS 0x00000001 |
| 45 | #define RWSEM_ACTIVE_MASK 0x0000ffff |
| 46 | #define RWSEM_WAITING_BIAS (-0x00010000) |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 47 | #else /* CONFIG_64BIT */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | #define RWSEM_UNLOCKED_VALUE 0x0000000000000000L |
| 49 | #define RWSEM_ACTIVE_BIAS 0x0000000000000001L |
| 50 | #define RWSEM_ACTIVE_MASK 0x00000000ffffffffL |
| 51 | #define RWSEM_WAITING_BIAS (-0x0000000100000000L) |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 52 | #endif /* CONFIG_64BIT */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | #define RWSEM_ACTIVE_READ_BIAS RWSEM_ACTIVE_BIAS |
| 54 | #define RWSEM_ACTIVE_WRITE_BIAS (RWSEM_WAITING_BIAS + RWSEM_ACTIVE_BIAS) |
| 55 | |
| 56 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | * lock for reading |
| 58 | */ |
| 59 | static inline void __down_read(struct rw_semaphore *sem) |
| 60 | { |
| 61 | signed long old, new; |
| 62 | |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 63 | asm volatile( |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 64 | #ifndef CONFIG_64BIT |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 65 | " l %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 66 | "0: lr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 67 | " ahi %1,%4\n" |
| 68 | " cs %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 69 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 70 | #else /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 71 | " lg %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 72 | "0: lgr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 73 | " aghi %1,%4\n" |
| 74 | " csg %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 75 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 76 | #endif /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 77 | : "=&d" (old), "=&d" (new), "=Q" (sem->count) |
| 78 | : "Q" (sem->count), "i" (RWSEM_ACTIVE_READ_BIAS) |
| 79 | : "cc", "memory"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | if (old < 0) |
| 81 | rwsem_down_read_failed(sem); |
| 82 | } |
| 83 | |
| 84 | /* |
| 85 | * trylock for reading -- returns 1 if successful, 0 if contention |
| 86 | */ |
| 87 | static inline int __down_read_trylock(struct rw_semaphore *sem) |
| 88 | { |
| 89 | signed long old, new; |
| 90 | |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 91 | asm volatile( |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 92 | #ifndef CONFIG_64BIT |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 93 | " l %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 94 | "0: ltr %1,%0\n" |
| 95 | " jm 1f\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 96 | " ahi %1,%4\n" |
| 97 | " cs %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 98 | " jl 0b\n" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 99 | "1:" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 100 | #else /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 101 | " lg %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 102 | "0: ltgr %1,%0\n" |
| 103 | " jm 1f\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 104 | " aghi %1,%4\n" |
| 105 | " csg %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 106 | " jl 0b\n" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | "1:" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 108 | #endif /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 109 | : "=&d" (old), "=&d" (new), "=Q" (sem->count) |
| 110 | : "Q" (sem->count), "i" (RWSEM_ACTIVE_READ_BIAS) |
| 111 | : "cc", "memory"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | return old >= 0 ? 1 : 0; |
| 113 | } |
| 114 | |
| 115 | /* |
| 116 | * lock for writing |
| 117 | */ |
Ingo Molnar | 4ea2176 | 2006-07-03 00:24:53 -0700 | [diff] [blame] | 118 | static inline void __down_write_nested(struct rw_semaphore *sem, int subclass) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | { |
| 120 | signed long old, new, tmp; |
| 121 | |
| 122 | tmp = RWSEM_ACTIVE_WRITE_BIAS; |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 123 | asm volatile( |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 124 | #ifndef CONFIG_64BIT |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 125 | " l %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 126 | "0: lr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 127 | " a %1,%4\n" |
| 128 | " cs %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 129 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 130 | #else /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 131 | " lg %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 132 | "0: lgr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 133 | " ag %1,%4\n" |
| 134 | " csg %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 135 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 136 | #endif /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 137 | : "=&d" (old), "=&d" (new), "=Q" (sem->count) |
| 138 | : "Q" (sem->count), "m" (tmp) |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 139 | : "cc", "memory"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | if (old != 0) |
| 141 | rwsem_down_write_failed(sem); |
| 142 | } |
| 143 | |
Ingo Molnar | 4ea2176 | 2006-07-03 00:24:53 -0700 | [diff] [blame] | 144 | static inline void __down_write(struct rw_semaphore *sem) |
| 145 | { |
| 146 | __down_write_nested(sem, 0); |
| 147 | } |
| 148 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 149 | /* |
| 150 | * trylock for writing -- returns 1 if successful, 0 if contention |
| 151 | */ |
| 152 | static inline int __down_write_trylock(struct rw_semaphore *sem) |
| 153 | { |
| 154 | signed long old; |
| 155 | |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 156 | asm volatile( |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 157 | #ifndef CONFIG_64BIT |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 158 | " l %0,%1\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 159 | "0: ltr %0,%0\n" |
| 160 | " jnz 1f\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 161 | " cs %0,%3,%1\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 162 | " jl 0b\n" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 163 | #else /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 164 | " lg %0,%1\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 165 | "0: ltgr %0,%0\n" |
| 166 | " jnz 1f\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 167 | " csg %0,%3,%1\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 168 | " jl 0b\n" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 169 | #endif /* CONFIG_64BIT */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 170 | "1:" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 171 | : "=&d" (old), "=Q" (sem->count) |
| 172 | : "Q" (sem->count), "d" (RWSEM_ACTIVE_WRITE_BIAS) |
| 173 | : "cc", "memory"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | return (old == RWSEM_UNLOCKED_VALUE) ? 1 : 0; |
| 175 | } |
| 176 | |
| 177 | /* |
| 178 | * unlock after reading |
| 179 | */ |
| 180 | static inline void __up_read(struct rw_semaphore *sem) |
| 181 | { |
| 182 | signed long old, new; |
| 183 | |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 184 | asm volatile( |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 185 | #ifndef CONFIG_64BIT |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 186 | " l %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 187 | "0: lr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 188 | " ahi %1,%4\n" |
| 189 | " cs %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 190 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 191 | #else /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 192 | " lg %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 193 | "0: lgr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 194 | " aghi %1,%4\n" |
| 195 | " csg %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 196 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 197 | #endif /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 198 | : "=&d" (old), "=&d" (new), "=Q" (sem->count) |
| 199 | : "Q" (sem->count), "i" (-RWSEM_ACTIVE_READ_BIAS) |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 200 | : "cc", "memory"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 201 | if (new < 0) |
| 202 | if ((new & RWSEM_ACTIVE_MASK) == 0) |
| 203 | rwsem_wake(sem); |
| 204 | } |
| 205 | |
| 206 | /* |
| 207 | * unlock after writing |
| 208 | */ |
| 209 | static inline void __up_write(struct rw_semaphore *sem) |
| 210 | { |
| 211 | signed long old, new, tmp; |
| 212 | |
| 213 | tmp = -RWSEM_ACTIVE_WRITE_BIAS; |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 214 | asm volatile( |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 215 | #ifndef CONFIG_64BIT |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 216 | " l %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 217 | "0: lr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 218 | " a %1,%4\n" |
| 219 | " cs %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 220 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 221 | #else /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 222 | " lg %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 223 | "0: lgr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 224 | " ag %1,%4\n" |
| 225 | " csg %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 226 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 227 | #endif /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 228 | : "=&d" (old), "=&d" (new), "=Q" (sem->count) |
| 229 | : "Q" (sem->count), "m" (tmp) |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 230 | : "cc", "memory"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | if (new < 0) |
| 232 | if ((new & RWSEM_ACTIVE_MASK) == 0) |
| 233 | rwsem_wake(sem); |
| 234 | } |
| 235 | |
| 236 | /* |
| 237 | * downgrade write lock to read lock |
| 238 | */ |
| 239 | static inline void __downgrade_write(struct rw_semaphore *sem) |
| 240 | { |
| 241 | signed long old, new, tmp; |
| 242 | |
| 243 | tmp = -RWSEM_WAITING_BIAS; |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 244 | asm volatile( |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 245 | #ifndef CONFIG_64BIT |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 246 | " l %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 247 | "0: lr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 248 | " a %1,%4\n" |
| 249 | " cs %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 250 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 251 | #else /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 252 | " lg %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 253 | "0: lgr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 254 | " ag %1,%4\n" |
| 255 | " csg %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 256 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 257 | #endif /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 258 | : "=&d" (old), "=&d" (new), "=Q" (sem->count) |
| 259 | : "Q" (sem->count), "m" (tmp) |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 260 | : "cc", "memory"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 261 | if (new > 1) |
| 262 | rwsem_downgrade_wake(sem); |
| 263 | } |
| 264 | |
| 265 | /* |
| 266 | * implement atomic add functionality |
| 267 | */ |
| 268 | static inline void rwsem_atomic_add(long delta, struct rw_semaphore *sem) |
| 269 | { |
| 270 | signed long old, new; |
| 271 | |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 272 | asm volatile( |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 273 | #ifndef CONFIG_64BIT |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 274 | " l %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 275 | "0: lr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 276 | " ar %1,%4\n" |
| 277 | " cs %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 278 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 279 | #else /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 280 | " lg %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 281 | "0: lgr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 282 | " agr %1,%4\n" |
| 283 | " csg %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 284 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 285 | #endif /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 286 | : "=&d" (old), "=&d" (new), "=Q" (sem->count) |
| 287 | : "Q" (sem->count), "d" (delta) |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 288 | : "cc", "memory"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 289 | } |
| 290 | |
| 291 | /* |
| 292 | * implement exchange and add functionality |
| 293 | */ |
| 294 | static inline long rwsem_atomic_update(long delta, struct rw_semaphore *sem) |
| 295 | { |
| 296 | signed long old, new; |
| 297 | |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 298 | asm volatile( |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 299 | #ifndef CONFIG_64BIT |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 300 | " l %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 301 | "0: lr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 302 | " ar %1,%4\n" |
| 303 | " cs %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 304 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 305 | #else /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 306 | " lg %0,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 307 | "0: lgr %1,%0\n" |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 308 | " agr %1,%4\n" |
| 309 | " csg %0,%1,%2\n" |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 310 | " jl 0b" |
Heiko Carstens | f4815ac | 2012-05-23 16:24:51 +0200 | [diff] [blame] | 311 | #endif /* CONFIG_64BIT */ |
Martin Schwidefsky | 987bcda | 2010-02-26 22:37:31 +0100 | [diff] [blame] | 312 | : "=&d" (old), "=&d" (new), "=Q" (sem->count) |
| 313 | : "Q" (sem->count), "d" (delta) |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 314 | : "cc", "memory"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 315 | return new; |
| 316 | } |
| 317 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 318 | #endif /* _S390_RWSEM_H */ |