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-rw-r--r--include/asm-s390/spinlock.h252
1 files changed, 78 insertions, 174 deletions
diff --git a/include/asm-s390/spinlock.h b/include/asm-s390/spinlock.h
index 53cc736b9820..8ff10300f7ee 100644
--- a/include/asm-s390/spinlock.h
+++ b/include/asm-s390/spinlock.h
@@ -11,21 +11,16 @@
11#ifndef __ASM_SPINLOCK_H 11#ifndef __ASM_SPINLOCK_H
12#define __ASM_SPINLOCK_H 12#define __ASM_SPINLOCK_H
13 13
14#ifdef __s390x__ 14static inline int
15/* 15_raw_compare_and_swap(volatile unsigned int *lock,
16 * Grmph, take care of %&#! user space programs that include 16 unsigned int old, unsigned int new)
17 * asm/spinlock.h. The diagnose is only available in kernel 17{
18 * context. 18 asm volatile ("cs %0,%3,0(%4)"
19 */ 19 : "=d" (old), "=m" (*lock)
20#ifdef __KERNEL__ 20 : "0" (old), "d" (new), "a" (lock), "m" (*lock)
21#include <asm/lowcore.h> 21 : "cc", "memory" );
22#define __DIAG44_INSN "ex" 22 return old;
23#define __DIAG44_OPERAND __LC_DIAG44_OPCODE 23}
24#else
25#define __DIAG44_INSN "#"
26#define __DIAG44_OPERAND 0
27#endif
28#endif /* __s390x__ */
29 24
30/* 25/*
31 * Simple spin lock operations. There are two variants, one clears IRQ's 26 * Simple spin lock operations. There are two variants, one clears IRQ's
@@ -41,58 +36,35 @@ typedef struct {
41#endif 36#endif
42} __attribute__ ((aligned (4))) spinlock_t; 37} __attribute__ ((aligned (4))) spinlock_t;
43 38
44#define SPIN_LOCK_UNLOCKED (spinlock_t) { 0 } 39#define SPIN_LOCK_UNLOCKED (spinlock_t) { 0 }
45#define spin_lock_init(lp) do { (lp)->lock = 0; } while(0) 40#define spin_lock_init(lp) do { (lp)->lock = 0; } while(0)
46#define spin_unlock_wait(lp) do { barrier(); } while(((volatile spinlock_t *)(lp))->lock) 41#define spin_unlock_wait(lp) do { barrier(); } while(((volatile spinlock_t *)(lp))->lock)
47#define spin_is_locked(x) ((x)->lock != 0) 42#define spin_is_locked(x) ((x)->lock != 0)
48#define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock) 43#define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock)
49 44
50extern inline void _raw_spin_lock(spinlock_t *lp) 45extern void _raw_spin_lock_wait(spinlock_t *lp, unsigned int pc);
46extern int _raw_spin_trylock_retry(spinlock_t *lp, unsigned int pc);
47
48static inline void _raw_spin_lock(spinlock_t *lp)
51{ 49{
52#ifndef __s390x__ 50 unsigned long pc = (unsigned long) __builtin_return_address(0);
53 unsigned int reg1, reg2; 51
54 __asm__ __volatile__(" bras %0,1f\n" 52 if (unlikely(_raw_compare_and_swap(&lp->lock, 0, pc) != 0))
55 "0: diag 0,0,68\n" 53 _raw_spin_lock_wait(lp, pc);
56 "1: slr %1,%1\n"
57 " cs %1,%0,0(%3)\n"
58 " jl 0b\n"
59 : "=&d" (reg1), "=&d" (reg2), "=m" (lp->lock)
60 : "a" (&lp->lock), "m" (lp->lock)
61 : "cc", "memory" );
62#else /* __s390x__ */
63 unsigned long reg1, reg2;
64 __asm__ __volatile__(" bras %1,1f\n"
65 "0: " __DIAG44_INSN " 0,%4\n"
66 "1: slr %0,%0\n"
67 " cs %0,%1,0(%3)\n"
68 " jl 0b\n"
69 : "=&d" (reg1), "=&d" (reg2), "=m" (lp->lock)
70 : "a" (&lp->lock), "i" (__DIAG44_OPERAND),
71 "m" (lp->lock) : "cc", "memory" );
72#endif /* __s390x__ */
73} 54}
74 55
75extern inline int _raw_spin_trylock(spinlock_t *lp) 56static inline int _raw_spin_trylock(spinlock_t *lp)
76{ 57{
77 unsigned long reg; 58 unsigned long pc = (unsigned long) __builtin_return_address(0);
78 unsigned int result; 59
79 60 if (likely(_raw_compare_and_swap(&lp->lock, 0, pc) == 0))
80 __asm__ __volatile__(" basr %1,0\n" 61 return 1;
81 "0: cs %0,%1,0(%3)" 62 return _raw_spin_trylock_retry(lp, pc);
82 : "=d" (result), "=&d" (reg), "=m" (lp->lock)
83 : "a" (&lp->lock), "m" (lp->lock), "0" (0)
84 : "cc", "memory" );
85 return !result;
86} 63}
87 64
88extern inline void _raw_spin_unlock(spinlock_t *lp) 65static inline void _raw_spin_unlock(spinlock_t *lp)
89{ 66{
90 unsigned int old; 67 _raw_compare_and_swap(&lp->lock, lp->lock, 0);
91
92 __asm__ __volatile__("cs %0,%3,0(%4)"
93 : "=d" (old), "=m" (lp->lock)
94 : "0" (lp->lock), "d" (0), "a" (lp)
95 : "cc", "memory" );
96} 68}
97 69
98/* 70/*
@@ -106,7 +78,7 @@ extern inline void _raw_spin_unlock(spinlock_t *lp)
106 * read-locks. 78 * read-locks.
107 */ 79 */
108typedef struct { 80typedef struct {
109 volatile unsigned long lock; 81 volatile unsigned int lock;
110 volatile unsigned long owner_pc; 82 volatile unsigned long owner_pc;
111#ifdef CONFIG_PREEMPT 83#ifdef CONFIG_PREEMPT
112 unsigned int break_lock; 84 unsigned int break_lock;
@@ -129,123 +101,55 @@ typedef struct {
129 */ 101 */
130#define write_can_lock(x) ((x)->lock == 0) 102#define write_can_lock(x) ((x)->lock == 0)
131 103
132#ifndef __s390x__ 104extern void _raw_read_lock_wait(rwlock_t *lp);
133#define _raw_read_lock(rw) \ 105extern int _raw_read_trylock_retry(rwlock_t *lp);
134 asm volatile(" l 2,0(%1)\n" \ 106extern void _raw_write_lock_wait(rwlock_t *lp);
135 " j 1f\n" \ 107extern int _raw_write_trylock_retry(rwlock_t *lp);
136 "0: diag 0,0,68\n" \ 108
137 "1: la 2,0(2)\n" /* clear high (=write) bit */ \ 109static inline void _raw_read_lock(rwlock_t *rw)
138 " la 3,1(2)\n" /* one more reader */ \ 110{
139 " cs 2,3,0(%1)\n" /* try to write new value */ \ 111 unsigned int old;
140 " jl 0b" \ 112 old = rw->lock & 0x7fffffffU;
141 : "=m" ((rw)->lock) : "a" (&(rw)->lock), \ 113 if (_raw_compare_and_swap(&rw->lock, old, old + 1) != old)
142 "m" ((rw)->lock) : "2", "3", "cc", "memory" ) 114 _raw_read_lock_wait(rw);
143#else /* __s390x__ */ 115}
144#define _raw_read_lock(rw) \ 116
145 asm volatile(" lg 2,0(%1)\n" \ 117static inline void _raw_read_unlock(rwlock_t *rw)
146 " j 1f\n" \ 118{
147 "0: " __DIAG44_INSN " 0,%2\n" \ 119 unsigned int old, cmp;
148 "1: nihh 2,0x7fff\n" /* clear high (=write) bit */ \ 120
149 " la 3,1(2)\n" /* one more reader */ \ 121 old = rw->lock;
150 " csg 2,3,0(%1)\n" /* try to write new value */ \ 122 do {
151 " jl 0b" \ 123 cmp = old;
152 : "=m" ((rw)->lock) \ 124 old = _raw_compare_and_swap(&rw->lock, old, old - 1);
153 : "a" (&(rw)->lock), "i" (__DIAG44_OPERAND), \ 125 } while (cmp != old);
154 "m" ((rw)->lock) : "2", "3", "cc", "memory" ) 126}
155#endif /* __s390x__ */ 127
156 128static inline void _raw_write_lock(rwlock_t *rw)
157#ifndef __s390x__ 129{
158#define _raw_read_unlock(rw) \ 130 if (unlikely(_raw_compare_and_swap(&rw->lock, 0, 0x80000000) != 0))
159 asm volatile(" l 2,0(%1)\n" \ 131 _raw_write_lock_wait(rw);
160 " j 1f\n" \ 132}
161 "0: diag 0,0,68\n" \ 133
162 "1: lr 3,2\n" \ 134static inline void _raw_write_unlock(rwlock_t *rw)
163 " ahi 3,-1\n" /* one less reader */ \ 135{
164 " cs 2,3,0(%1)\n" \ 136 _raw_compare_and_swap(&rw->lock, 0x80000000, 0);
165 " jl 0b" \ 137}
166 : "=m" ((rw)->lock) : "a" (&(rw)->lock), \ 138
167 "m" ((rw)->lock) : "2", "3", "cc", "memory" ) 139static inline int _raw_read_trylock(rwlock_t *rw)
168#else /* __s390x__ */ 140{
169#define _raw_read_unlock(rw) \ 141 unsigned int old;
170 asm volatile(" lg 2,0(%1)\n" \ 142 old = rw->lock & 0x7fffffffU;
171 " j 1f\n" \ 143 if (likely(_raw_compare_and_swap(&rw->lock, old, old + 1) == old))
172 "0: " __DIAG44_INSN " 0,%2\n" \ 144 return 1;
173 "1: lgr 3,2\n" \ 145 return _raw_read_trylock_retry(rw);
174 " bctgr 3,0\n" /* one less reader */ \ 146}
175 " csg 2,3,0(%1)\n" \ 147
176 " jl 0b" \ 148static inline int _raw_write_trylock(rwlock_t *rw)
177 : "=m" ((rw)->lock) \
178 : "a" (&(rw)->lock), "i" (__DIAG44_OPERAND), \
179 "m" ((rw)->lock) : "2", "3", "cc", "memory" )
180#endif /* __s390x__ */
181
182#ifndef __s390x__
183#define _raw_write_lock(rw) \
184 asm volatile(" lhi 3,1\n" \
185 " sll 3,31\n" /* new lock value = 0x80000000 */ \
186 " j 1f\n" \
187 "0: diag 0,0,68\n" \
188 "1: slr 2,2\n" /* old lock value must be 0 */ \
189 " cs 2,3,0(%1)\n" \
190 " jl 0b" \
191 : "=m" ((rw)->lock) : "a" (&(rw)->lock), \
192 "m" ((rw)->lock) : "2", "3", "cc", "memory" )
193#else /* __s390x__ */
194#define _raw_write_lock(rw) \
195 asm volatile(" llihh 3,0x8000\n" /* new lock value = 0x80...0 */ \
196 " j 1f\n" \
197 "0: " __DIAG44_INSN " 0,%2\n" \
198 "1: slgr 2,2\n" /* old lock value must be 0 */ \
199 " csg 2,3,0(%1)\n" \
200 " jl 0b" \
201 : "=m" ((rw)->lock) \
202 : "a" (&(rw)->lock), "i" (__DIAG44_OPERAND), \
203 "m" ((rw)->lock) : "2", "3", "cc", "memory" )
204#endif /* __s390x__ */
205
206#ifndef __s390x__
207#define _raw_write_unlock(rw) \
208 asm volatile(" slr 3,3\n" /* new lock value = 0 */ \
209 " j 1f\n" \
210 "0: diag 0,0,68\n" \
211 "1: lhi 2,1\n" \
212 " sll 2,31\n" /* old lock value must be 0x80000000 */ \
213 " cs 2,3,0(%1)\n" \
214 " jl 0b" \
215 : "=m" ((rw)->lock) : "a" (&(rw)->lock), \
216 "m" ((rw)->lock) : "2", "3", "cc", "memory" )
217#else /* __s390x__ */
218#define _raw_write_unlock(rw) \
219 asm volatile(" slgr 3,3\n" /* new lock value = 0 */ \
220 " j 1f\n" \
221 "0: " __DIAG44_INSN " 0,%2\n" \
222 "1: llihh 2,0x8000\n" /* old lock value must be 0x8..0 */\
223 " csg 2,3,0(%1)\n" \
224 " jl 0b" \
225 : "=m" ((rw)->lock) \
226 : "a" (&(rw)->lock), "i" (__DIAG44_OPERAND), \
227 "m" ((rw)->lock) : "2", "3", "cc", "memory" )
228#endif /* __s390x__ */
229
230#define _raw_read_trylock(lock) generic_raw_read_trylock(lock)
231
232extern inline int _raw_write_trylock(rwlock_t *rw)
233{ 149{
234 unsigned long result, reg; 150 if (likely(_raw_compare_and_swap(&rw->lock, 0, 0x80000000) == 0))
235 151 return 1;
236 __asm__ __volatile__( 152 return _raw_write_trylock_retry(rw);
237#ifndef __s390x__
238 " lhi %1,1\n"
239 " sll %1,31\n"
240 " cs %0,%1,0(%3)"
241#else /* __s390x__ */
242 " llihh %1,0x8000\n"
243 "0: csg %0,%1,0(%3)\n"
244#endif /* __s390x__ */
245 : "=d" (result), "=&d" (reg), "=m" (rw->lock)
246 : "a" (&rw->lock), "m" (rw->lock), "0" (0UL)
247 : "cc", "memory" );
248 return result == 0;
249} 153}
250 154
251#endif /* __ASM_SPINLOCK_H */ 155#endif /* __ASM_SPINLOCK_H */
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