1 #ifndef _ARCH_MIPS_LOCAL_H 2 #define _ARCH_MIPS_LOCAL_H 3 4 #include <linux/percpu.h> 5 #include <linux/bitops.h> 6 #include <linux/atomic.h> 7 #include <asm/cmpxchg.h> 8 #include <asm/war.h> 9 10 typedef struct 11 { 12 atomic_long_t a; 13 } local_t; 14 15 #define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) } 16 17 #define local_read(l) atomic_long_read(&(l)->a) 18 #define local_set(l, i) atomic_long_set(&(l)->a, (i)) 19 20 #define local_add(i, l) atomic_long_add((i), (&(l)->a)) 21 #define local_sub(i, l) atomic_long_sub((i), (&(l)->a)) 22 #define local_inc(l) atomic_long_inc(&(l)->a) 23 #define local_dec(l) atomic_long_dec(&(l)->a) 24 25 /* 26 * Same as above, but return the result value 27 */ 28 static __inline__ long local_add_return(long i, local_t * l) 29 { 30 unsigned long result; 31 32 if (kernel_uses_llsc && R10000_LLSC_WAR) { 33 unsigned long temp; 34 35 __asm__ __volatile__( 36 " .set arch=r4000 \n" 37 "1:" __LL "%1, %2 # local_add_return \n" 38 " addu %0, %1, %3 \n" 39 __SC "%0, %2 \n" 40 " beqzl %0, 1b \n" 41 " addu %0, %1, %3 \n" 42 " .set mips0 \n" 43 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 44 : "Ir" (i), "m" (l->a.counter) 45 : "memory"); 46 } else if (kernel_uses_llsc) { 47 unsigned long temp; 48 49 __asm__ __volatile__( 50 " .set arch=r4000 \n" 51 "1:" __LL "%1, %2 # local_add_return \n" 52 " addu %0, %1, %3 \n" 53 __SC "%0, %2 \n" 54 " beqz %0, 1b \n" 55 " addu %0, %1, %3 \n" 56 " .set mips0 \n" 57 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 58 : "Ir" (i), "m" (l->a.counter) 59 : "memory"); 60 } else { 61 unsigned long flags; 62 63 local_irq_save(flags); 64 result = l->a.counter; 65 result += i; 66 l->a.counter = result; 67 local_irq_restore(flags); 68 } 69 70 return result; 71 } 72 73 static __inline__ long local_sub_return(long i, local_t * l) 74 { 75 unsigned long result; 76 77 if (kernel_uses_llsc && R10000_LLSC_WAR) { 78 unsigned long temp; 79 80 __asm__ __volatile__( 81 " .set arch=r4000 \n" 82 "1:" __LL "%1, %2 # local_sub_return \n" 83 " subu %0, %1, %3 \n" 84 __SC "%0, %2 \n" 85 " beqzl %0, 1b \n" 86 " subu %0, %1, %3 \n" 87 " .set mips0 \n" 88 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 89 : "Ir" (i), "m" (l->a.counter) 90 : "memory"); 91 } else if (kernel_uses_llsc) { 92 unsigned long temp; 93 94 __asm__ __volatile__( 95 " .set arch=r4000 \n" 96 "1:" __LL "%1, %2 # local_sub_return \n" 97 " subu %0, %1, %3 \n" 98 __SC "%0, %2 \n" 99 " beqz %0, 1b \n" 100 " subu %0, %1, %3 \n" 101 " .set mips0 \n" 102 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 103 : "Ir" (i), "m" (l->a.counter) 104 : "memory"); 105 } else { 106 unsigned long flags; 107 108 local_irq_save(flags); 109 result = l->a.counter; 110 result -= i; 111 l->a.counter = result; 112 local_irq_restore(flags); 113 } 114 115 return result; 116 } 117 118 #define local_cmpxchg(l, o, n) \ 119 ((long)cmpxchg_local(&((l)->a.counter), (o), (n))) 120 #define local_xchg(l, n) (atomic_long_xchg((&(l)->a), (n))) 121 122 /** 123 * local_add_unless - add unless the number is a given value 124 * @l: pointer of type local_t 125 * @a: the amount to add to l... 126 * @u: ...unless l is equal to u. 127 * 128 * Atomically adds @a to @l, so long as it was not @u. 129 * Returns non-zero if @l was not @u, and zero otherwise. 130 */ 131 #define local_add_unless(l, a, u) \ 132 ({ \ 133 long c, old; \ 134 c = local_read(l); \ 135 while (c != (u) && (old = local_cmpxchg((l), c, c + (a))) != c) \ 136 c = old; \ 137 c != (u); \ 138 }) 139 #define local_inc_not_zero(l) local_add_unless((l), 1, 0) 140 141 #define local_dec_return(l) local_sub_return(1, (l)) 142 #define local_inc_return(l) local_add_return(1, (l)) 143 144 /* 145 * local_sub_and_test - subtract value from variable and test result 146 * @i: integer value to subtract 147 * @l: pointer of type local_t 148 * 149 * Atomically subtracts @i from @l and returns 150 * true if the result is zero, or false for all 151 * other cases. 152 */ 153 #define local_sub_and_test(i, l) (local_sub_return((i), (l)) == 0) 154 155 /* 156 * local_inc_and_test - increment and test 157 * @l: pointer of type local_t 158 * 159 * Atomically increments @l by 1 160 * and returns true if the result is zero, or false for all 161 * other cases. 162 */ 163 #define local_inc_and_test(l) (local_inc_return(l) == 0) 164 165 /* 166 * local_dec_and_test - decrement by 1 and test 167 * @l: pointer of type local_t 168 * 169 * Atomically decrements @l by 1 and 170 * returns true if the result is 0, or false for all other 171 * cases. 172 */ 173 #define local_dec_and_test(l) (local_sub_return(1, (l)) == 0) 174 175 /* 176 * local_add_negative - add and test if negative 177 * @l: pointer of type local_t 178 * @i: integer value to add 179 * 180 * Atomically adds @i to @l and returns true 181 * if the result is negative, or false when 182 * result is greater than or equal to zero. 183 */ 184 #define local_add_negative(i, l) (local_add_return(i, (l)) < 0) 185 186 /* Use these for per-cpu local_t variables: on some archs they are 187 * much more efficient than these naive implementations. Note they take 188 * a variable, not an address. 189 */ 190 191 #define __local_inc(l) ((l)->a.counter++) 192 #define __local_dec(l) ((l)->a.counter++) 193 #define __local_add(i, l) ((l)->a.counter+=(i)) 194 #define __local_sub(i, l) ((l)->a.counter-=(i)) 195 196 #endif /* _ARCH_MIPS_LOCAL_H */ 197