1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ARCH_MIPS_LOCAL_H 3 #define _ARCH_MIPS_LOCAL_H 4 5 #include <linux/percpu.h> 6 #include <linux/bitops.h> 7 #include <linux/atomic.h> 8 #include <asm/cmpxchg.h> 9 #include <asm/compiler.h> 10 #include <asm/war.h> 11 12 typedef struct 13 { 14 atomic_long_t a; 15 } local_t; 16 17 #define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) } 18 19 #define local_read(l) atomic_long_read(&(l)->a) 20 #define local_set(l, i) atomic_long_set(&(l)->a, (i)) 21 22 #define local_add(i, l) atomic_long_add((i), (&(l)->a)) 23 #define local_sub(i, l) atomic_long_sub((i), (&(l)->a)) 24 #define local_inc(l) atomic_long_inc(&(l)->a) 25 #define local_dec(l) atomic_long_dec(&(l)->a) 26 27 /* 28 * Same as above, but return the result value 29 */ 30 static __inline__ long local_add_return(long i, local_t * l) 31 { 32 unsigned long result; 33 34 if (kernel_uses_llsc && R10000_LLSC_WAR) { 35 unsigned long temp; 36 37 __asm__ __volatile__( 38 " .set arch=r4000 \n" 39 "1:" __LL "%1, %2 # local_add_return \n" 40 " addu %0, %1, %3 \n" 41 __SC "%0, %2 \n" 42 " beqzl %0, 1b \n" 43 " addu %0, %1, %3 \n" 44 " .set mips0 \n" 45 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 46 : "Ir" (i), "m" (l->a.counter) 47 : "memory"); 48 } else if (kernel_uses_llsc) { 49 unsigned long temp; 50 51 __asm__ __volatile__( 52 " .set "MIPS_ISA_ARCH_LEVEL" \n" 53 "1:" __LL "%1, %2 # local_add_return \n" 54 " addu %0, %1, %3 \n" 55 __SC "%0, %2 \n" 56 " beqz %0, 1b \n" 57 " addu %0, %1, %3 \n" 58 " .set mips0 \n" 59 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 60 : "Ir" (i), "m" (l->a.counter) 61 : "memory"); 62 } else { 63 unsigned long flags; 64 65 local_irq_save(flags); 66 result = l->a.counter; 67 result += i; 68 l->a.counter = result; 69 local_irq_restore(flags); 70 } 71 72 return result; 73 } 74 75 static __inline__ long local_sub_return(long i, local_t * l) 76 { 77 unsigned long result; 78 79 if (kernel_uses_llsc && R10000_LLSC_WAR) { 80 unsigned long temp; 81 82 __asm__ __volatile__( 83 " .set arch=r4000 \n" 84 "1:" __LL "%1, %2 # local_sub_return \n" 85 " subu %0, %1, %3 \n" 86 __SC "%0, %2 \n" 87 " beqzl %0, 1b \n" 88 " subu %0, %1, %3 \n" 89 " .set mips0 \n" 90 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 91 : "Ir" (i), "m" (l->a.counter) 92 : "memory"); 93 } else if (kernel_uses_llsc) { 94 unsigned long temp; 95 96 __asm__ __volatile__( 97 " .set "MIPS_ISA_ARCH_LEVEL" \n" 98 "1:" __LL "%1, %2 # local_sub_return \n" 99 " subu %0, %1, %3 \n" 100 __SC "%0, %2 \n" 101 " beqz %0, 1b \n" 102 " subu %0, %1, %3 \n" 103 " .set mips0 \n" 104 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 105 : "Ir" (i), "m" (l->a.counter) 106 : "memory"); 107 } else { 108 unsigned long flags; 109 110 local_irq_save(flags); 111 result = l->a.counter; 112 result -= i; 113 l->a.counter = result; 114 local_irq_restore(flags); 115 } 116 117 return result; 118 } 119 120 #define local_cmpxchg(l, o, n) \ 121 ((long)cmpxchg_local(&((l)->a.counter), (o), (n))) 122 #define local_xchg(l, n) (atomic_long_xchg((&(l)->a), (n))) 123 124 /** 125 * local_add_unless - add unless the number is a given value 126 * @l: pointer of type local_t 127 * @a: the amount to add to l... 128 * @u: ...unless l is equal to u. 129 * 130 * Atomically adds @a to @l, so long as it was not @u. 131 * Returns non-zero if @l was not @u, and zero otherwise. 132 */ 133 #define local_add_unless(l, a, u) \ 134 ({ \ 135 long c, old; \ 136 c = local_read(l); \ 137 while (c != (u) && (old = local_cmpxchg((l), c, c + (a))) != c) \ 138 c = old; \ 139 c != (u); \ 140 }) 141 #define local_inc_not_zero(l) local_add_unless((l), 1, 0) 142 143 #define local_dec_return(l) local_sub_return(1, (l)) 144 #define local_inc_return(l) local_add_return(1, (l)) 145 146 /* 147 * local_sub_and_test - subtract value from variable and test result 148 * @i: integer value to subtract 149 * @l: pointer of type local_t 150 * 151 * Atomically subtracts @i from @l and returns 152 * true if the result is zero, or false for all 153 * other cases. 154 */ 155 #define local_sub_and_test(i, l) (local_sub_return((i), (l)) == 0) 156 157 /* 158 * local_inc_and_test - increment and test 159 * @l: pointer of type local_t 160 * 161 * Atomically increments @l by 1 162 * and returns true if the result is zero, or false for all 163 * other cases. 164 */ 165 #define local_inc_and_test(l) (local_inc_return(l) == 0) 166 167 /* 168 * local_dec_and_test - decrement by 1 and test 169 * @l: pointer of type local_t 170 * 171 * Atomically decrements @l by 1 and 172 * returns true if the result is 0, or false for all other 173 * cases. 174 */ 175 #define local_dec_and_test(l) (local_sub_return(1, (l)) == 0) 176 177 /* 178 * local_add_negative - add and test if negative 179 * @l: pointer of type local_t 180 * @i: integer value to add 181 * 182 * Atomically adds @i to @l and returns true 183 * if the result is negative, or false when 184 * result is greater than or equal to zero. 185 */ 186 #define local_add_negative(i, l) (local_add_return(i, (l)) < 0) 187 188 /* Use these for per-cpu local_t variables: on some archs they are 189 * much more efficient than these naive implementations. Note they take 190 * a variable, not an address. 191 */ 192 193 #define __local_inc(l) ((l)->a.counter++) 194 #define __local_dec(l) ((l)->a.counter++) 195 #define __local_add(i, l) ((l)->a.counter+=(i)) 196 #define __local_sub(i, l) ((l)->a.counter-=(i)) 197 198 #endif /* _ARCH_MIPS_LOCAL_H */ 199