Gitiles
Code Review Sign In
review.evervolv.com / android_kernel_htc_msm8960 / f10bb2544bab75b3e8df15a7b51a833c78cbd77f / . / arch / sparc64 / lib / rwsem.S
blob: 75f0e6b951d61b9ff5ef5ecf4187bac65ea785bf [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]1/* rwsem.S: RW semaphore assembler.
2 *
3 * Written by David S. Miller (davem@redhat.com), 2001.
4 * Derived from asm-i386/rwsem.h
5 */
6
7#include <asm/rwsem-const.h>
8
9 .section .sched.text
10
11 .globl __down_read
12__down_read:
131: lduw [%o0], %g1
14 add %g1, 1, %g7
15 cas [%o0], %g1, %g7
16 cmp %g1, %g7
17 bne,pn %icc, 1b
18 add %g7, 1, %g7
19 cmp %g7, 0
David S. Millerb445e262005-06-27 15:42:04 -0700[diff] [blame]20 membar #StoreLoad | #StoreStore
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]21 bl,pn %icc, 3f
David S. Millerb445e262005-06-27 15:42:04 -0700[diff] [blame]22 nop
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]232:
24 retl
25 nop
263:
27 save %sp, -192, %sp
28 call rwsem_down_read_failed
29 mov %i0, %o0
30 ret
31 restore
32 .size __down_read, .-__down_read
33
34 .globl __down_read_trylock
35__down_read_trylock:
361: lduw [%o0], %g1
37 add %g1, 1, %g7
38 cmp %g7, 0
39 bl,pn %icc, 2f
40 mov 0, %o1
41 cas [%o0], %g1, %g7
42 cmp %g1, %g7
43 bne,pn %icc, 1b
44 mov 1, %o1
45 membar #StoreLoad | #StoreStore
462: retl
47 mov %o1, %o0
48 .size __down_read_trylock, .-__down_read_trylock
49
50 .globl __down_write
51__down_write:
52 sethi %hi(RWSEM_ACTIVE_WRITE_BIAS), %g1
53 or %g1, %lo(RWSEM_ACTIVE_WRITE_BIAS), %g1
541:
55 lduw [%o0], %g3
56 add %g3, %g1, %g7
57 cas [%o0], %g3, %g7
58 cmp %g3, %g7
59 bne,pn %icc, 1b
60 cmp %g7, 0
David S. Millerb445e262005-06-27 15:42:04 -0700[diff] [blame]61 membar #StoreLoad | #StoreStore
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]62 bne,pn %icc, 3f
David S. Millerb445e262005-06-27 15:42:04 -0700[diff] [blame]63 nop
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]642: retl
65 nop
663:
67 save %sp, -192, %sp
68 call rwsem_down_write_failed
69 mov %i0, %o0
70 ret
71 restore
72 .size __down_write, .-__down_write
73
74 .globl __down_write_trylock
75__down_write_trylock:
76 sethi %hi(RWSEM_ACTIVE_WRITE_BIAS), %g1
77 or %g1, %lo(RWSEM_ACTIVE_WRITE_BIAS), %g1
781:
79 lduw [%o0], %g3
80 cmp %g3, 0
81 bne,pn %icc, 2f
82 mov 0, %o1
83 add %g3, %g1, %g7
84 cas [%o0], %g3, %g7
85 cmp %g3, %g7
86 bne,pn %icc, 1b
87 mov 1, %o1
88 membar #StoreLoad | #StoreStore
892: retl
90 mov %o1, %o0
91 .size __down_write_trylock, .-__down_write_trylock
92
93 .globl __up_read
94__up_read:
951:
96 lduw [%o0], %g1
97 sub %g1, 1, %g7
98 cas [%o0], %g1, %g7
99 cmp %g1, %g7
100 bne,pn %icc, 1b
101 cmp %g7, 0
David S. Millerb445e262005-06-27 15:42:04 -0700[diff] [blame]102 membar #StoreLoad | #StoreStore
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]103 bl,pn %icc, 3f
David S. Millerb445e262005-06-27 15:42:04 -0700[diff] [blame]104 nop
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]1052: retl
106 nop
1073: sethi %hi(RWSEM_ACTIVE_MASK), %g1
108 sub %g7, 1, %g7
109 or %g1, %lo(RWSEM_ACTIVE_MASK), %g1
110 andcc %g7, %g1, %g0
111 bne,pn %icc, 2b
112 nop
113 save %sp, -192, %sp
114 call rwsem_wake
115 mov %i0, %o0
116 ret
117 restore
118 .size __up_read, .-__up_read
119
120 .globl __up_write
121__up_write:
122 sethi %hi(RWSEM_ACTIVE_WRITE_BIAS), %g1
123 or %g1, %lo(RWSEM_ACTIVE_WRITE_BIAS), %g1
1241:
125 lduw [%o0], %g3
126 sub %g3, %g1, %g7
127 cas [%o0], %g3, %g7
128 cmp %g3, %g7
129 bne,pn %icc, 1b
130 sub %g7, %g1, %g7
131 cmp %g7, 0
David S. Millerb445e262005-06-27 15:42:04 -0700[diff] [blame]132 membar #StoreLoad | #StoreStore
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]133 bl,pn %icc, 3f
David S. Millerb445e262005-06-27 15:42:04 -0700[diff] [blame]134 nop
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]1352:
136 retl
137 nop
1383:
139 save %sp, -192, %sp
140 call rwsem_wake
141 mov %i0, %o0
142 ret
143 restore
144 .size __up_write, .-__up_write
145
146 .globl __downgrade_write
147__downgrade_write:
148 sethi %hi(RWSEM_WAITING_BIAS), %g1
149 or %g1, %lo(RWSEM_WAITING_BIAS), %g1
1501:
151 lduw [%o0], %g3
152 sub %g3, %g1, %g7
153 cas [%o0], %g3, %g7
154 cmp %g3, %g7
155 bne,pn %icc, 1b
156 sub %g7, %g1, %g7
157 cmp %g7, 0
David S. Millerb445e262005-06-27 15:42:04 -0700[diff] [blame]158 membar #StoreLoad | #StoreStore
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]159 bl,pn %icc, 3f
David S. Millerb445e262005-06-27 15:42:04 -0700[diff] [blame]160 nop
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]1612:
162 retl
163 nop
1643:
165 save %sp, -192, %sp
166 call rwsem_downgrade_wake
167 mov %i0, %o0
168 ret
169 restore
170 .size __downgrade_write, .-__downgrade_write