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/compiler.h> 9 #include <asm/war.h> 10 11 typedef struct 12 { 13 atomic_long_t a; 14 } local_t; 15 16 #define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) } 17 18 #define local_read(l) atomic_long_read(&(l)->a) 19 #define local_set(l, i) atomic_long_set(&(l)->a, (i)) 20 21 #define local_add(i, l) atomic_long_add((i), (&(l)->a)) 22 #define local_sub(i, l) atomic_long_sub((i), (&(l)->a)) 23 #define local_inc(l) atomic_long_inc(&(l)->a) 24 #define local_dec(l) atomic_long_dec(&(l)->a) 25 26 /* 27 * Same as above, but return the result value 28 */ 29 static __inline__ long local_add_return(long i, local_t * l) 30 { 31 unsigned long result; 32 33 if (kernel_uses_llsc && R10000_LLSC_WAR) { 34 unsigned long temp; 35 36 __asm__ __volatile__( 37 " .set arch=r4000 \n" 38 "1:" __LL "%1, %2 # local_add_return \n" 39 " addu %0, %1, %3 \n" 40 __SC "%0, %2 \n" 41 " beqzl %0, 1b \n" 42 " addu %0, %1, %3 \n" 43 " .set mips0 \n" 44 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 45 : "Ir" (i), "m" (l->a.counter) 46 : "memory"); 47 } else if (kernel_uses_llsc) { 48 unsigned long temp; 49 50 __asm__ __volatile__( 51 " .set "MIPS_ISA_ARCH_LEVEL" \n" 52 "1:" __LL "%1, %2 # local_add_return \n" 53 " addu %0, %1, %3 \n" 54 __SC "%0, %2 \n" 55 " beqz %0, 1b \n" 56 " addu %0, %1, %3 \n" 57 " .set mips0 \n" 58 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 59 : "Ir" (i), "m" (l->a.counter) 60 : "memory"); 61 } else { 62 unsigned long flags; 63 64 local_irq_save(flags); 65 result = l->a.counter; 66 result += i; 67 l->a.counter = result; 68 local_irq_restore(flags); 69 } 70 71 return result; 72 } 73 74 static __inline__ long local_sub_return(long i, local_t * l) 75 { 76 unsigned long result; 77 78 if (kernel_uses_llsc && R10000_LLSC_WAR) { 79 unsigned long temp; 80 81 __asm__ __volatile__( 82 " .set arch=r4000 \n" 83 "1:" __LL "%1, %2 # local_sub_return \n" 84 " subu %0, %1, %3 \n" 85 __SC "%0, %2 \n" 86 " beqzl %0, 1b \n" 87 " subu %0, %1, %3 \n" 88 " .set mips0 \n" 89 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 90 : "Ir" (i), "m" (l->a.counter) 91 : "memory"); 92 } else if (kernel_uses_llsc) { 93 unsigned long temp; 94 95 __asm__ __volatile__( 96 " .set "MIPS_ISA_ARCH_LEVEL" \n" 97 "1:" __LL "%1, %2 # local_sub_return \n" 98 " subu %0, %1, %3 \n" 99 __SC "%0, %2 \n" 100 " beqz %0, 1b \n" 101 " subu %0, %1, %3 \n" 102 " .set mips0 \n" 103 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 104 : "Ir" (i), "m" (l->a.counter) 105 : "memory"); 106 } else { 107 unsigned long flags; 108 109 local_irq_save(flags); 110 result = l->a.counter; 111 result -= i; 112 l->a.counter = result; 113 local_irq_restore(flags); 114 } 115 116 return result; 117 } 118 119 #define local_cmpxchg(l, o, n) \ 120 ((long)cmpxchg_local(&((l)->a.counter), (o), (n))) 121 #define local_xchg(l, n) (atomic_long_xchg((&(l)->a), (n))) 122 123 /** 124 * local_add_unless - add unless the number is a given value 125 * @l: pointer of type local_t 126 * @a: the amount to add to l... 127 * @u: ...unless l is equal to u. 128 * 129 * Atomically adds @a to @l, so long as it was not @u. 130 * Returns non-zero if @l was not @u, and zero otherwise. 131 */ 132 #define local_add_unless(l, a, u) \ 133 ({ \ 134 long c, old; \ 135 c = local_read(l); \ 136 while (c != (u) && (old = local_cmpxchg((l), c, c + (a))) != c) \ 137 c = old; \ 138 c != (u); \ 139 }) 140 #define local_inc_not_zero(l) local_add_unless((l), 1, 0) 141 142 #define local_dec_return(l) local_sub_return(1, (l)) 143 #define local_inc_return(l) local_add_return(1, (l)) 144 145 /* 146 * local_sub_and_test - subtract value from variable and test result 147 * @i: integer value to subtract 148 * @l: pointer of type local_t 149 * 150 * Atomically subtracts @i from @l and returns 151 * true if the result is zero, or false for all 152 * other cases. 153 */ 154 #define local_sub_and_test(i, l) (local_sub_return((i), (l)) == 0) 155 156 /* 157 * local_inc_and_test - increment and test 158 * @l: pointer of type local_t 159 * 160 * Atomically increments @l by 1 161 * and returns true if the result is zero, or false for all 162 * other cases. 163 */ 164 #define local_inc_and_test(l) (local_inc_return(l) == 0) 165 166 /* 167 * local_dec_and_test - decrement by 1 and test 168 * @l: pointer of type local_t 169 * 170 * Atomically decrements @l by 1 and 171 * returns true if the result is 0, or false for all other 172 * cases. 173 */ 174 #define local_dec_and_test(l) (local_sub_return(1, (l)) == 0) 175 176 /* 177 * local_add_negative - add and test if negative 178 * @l: pointer of type local_t 179 * @i: integer value to add 180 * 181 * Atomically adds @i to @l and returns true 182 * if the result is negative, or false when 183 * result is greater than or equal to zero. 184 */ 185 #define local_add_negative(i, l) (local_add_return(i, (l)) < 0) 186 187 /* Use these for per-cpu local_t variables: on some archs they are 188 * much more efficient than these naive implementations. Note they take 189 * a variable, not an address. 190 */ 191 192 #define __local_inc(l) ((l)->a.counter++) 193 #define __local_dec(l) ((l)->a.counter++) 194 #define __local_add(i, l) ((l)->a.counter+=(i)) 195 #define __local_sub(i, l) ((l)->a.counter-=(i)) 196 197 #endif /* _ARCH_MIPS_LOCAL_H */ 198