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 push \n" 39 " .set arch=r4000 \n" 40 "1:" __LL "%1, %2 # local_add_return \n" 41 " addu %0, %1, %3 \n" 42 __SC "%0, %2 \n" 43 " beqzl %0, 1b \n" 44 " addu %0, %1, %3 \n" 45 " .set pop \n" 46 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 47 : "Ir" (i), "m" (l->a.counter) 48 : "memory"); 49 } else if (kernel_uses_llsc) { 50 unsigned long temp; 51 52 __asm__ __volatile__( 53 " .set push \n" 54 " .set "MIPS_ISA_ARCH_LEVEL" \n" 55 "1:" __LL "%1, %2 # local_add_return \n" 56 " addu %0, %1, %3 \n" 57 __SC "%0, %2 \n" 58 " beqz %0, 1b \n" 59 " addu %0, %1, %3 \n" 60 " .set pop \n" 61 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 62 : "Ir" (i), "m" (l->a.counter) 63 : "memory"); 64 } else { 65 unsigned long flags; 66 67 local_irq_save(flags); 68 result = l->a.counter; 69 result += i; 70 l->a.counter = result; 71 local_irq_restore(flags); 72 } 73 74 return result; 75 } 76 77 static __inline__ long local_sub_return(long i, local_t * l) 78 { 79 unsigned long result; 80 81 if (kernel_uses_llsc && R10000_LLSC_WAR) { 82 unsigned long temp; 83 84 __asm__ __volatile__( 85 " .set push \n" 86 " .set arch=r4000 \n" 87 "1:" __LL "%1, %2 # local_sub_return \n" 88 " subu %0, %1, %3 \n" 89 __SC "%0, %2 \n" 90 " beqzl %0, 1b \n" 91 " subu %0, %1, %3 \n" 92 " .set pop \n" 93 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 94 : "Ir" (i), "m" (l->a.counter) 95 : "memory"); 96 } else if (kernel_uses_llsc) { 97 unsigned long temp; 98 99 __asm__ __volatile__( 100 " .set push \n" 101 " .set "MIPS_ISA_ARCH_LEVEL" \n" 102 "1:" __LL "%1, %2 # local_sub_return \n" 103 " subu %0, %1, %3 \n" 104 __SC "%0, %2 \n" 105 " beqz %0, 1b \n" 106 " subu %0, %1, %3 \n" 107 " .set pop \n" 108 : "=&r" (result), "=&r" (temp), "=m" (l->a.counter) 109 : "Ir" (i), "m" (l->a.counter) 110 : "memory"); 111 } else { 112 unsigned long flags; 113 114 local_irq_save(flags); 115 result = l->a.counter; 116 result -= i; 117 l->a.counter = result; 118 local_irq_restore(flags); 119 } 120 121 return result; 122 } 123 124 #define local_cmpxchg(l, o, n) \ 125 ((long)cmpxchg_local(&((l)->a.counter), (o), (n))) 126 #define local_xchg(l, n) (atomic_long_xchg((&(l)->a), (n))) 127 128 /** 129 * local_add_unless - add unless the number is a given value 130 * @l: pointer of type local_t 131 * @a: the amount to add to l... 132 * @u: ...unless l is equal to u. 133 * 134 * Atomically adds @a to @l, so long as it was not @u. 135 * Returns non-zero if @l was not @u, and zero otherwise. 136 */ 137 #define local_add_unless(l, a, u) \ 138 ({ \ 139 long c, old; \ 140 c = local_read(l); \ 141 while (c != (u) && (old = local_cmpxchg((l), c, c + (a))) != c) \ 142 c = old; \ 143 c != (u); \ 144 }) 145 #define local_inc_not_zero(l) local_add_unless((l), 1, 0) 146 147 #define local_dec_return(l) local_sub_return(1, (l)) 148 #define local_inc_return(l) local_add_return(1, (l)) 149 150 /* 151 * local_sub_and_test - subtract value from variable and test result 152 * @i: integer value to subtract 153 * @l: pointer of type local_t 154 * 155 * Atomically subtracts @i from @l and returns 156 * true if the result is zero, or false for all 157 * other cases. 158 */ 159 #define local_sub_and_test(i, l) (local_sub_return((i), (l)) == 0) 160 161 /* 162 * local_inc_and_test - increment and test 163 * @l: pointer of type local_t 164 * 165 * Atomically increments @l by 1 166 * and returns true if the result is zero, or false for all 167 * other cases. 168 */ 169 #define local_inc_and_test(l) (local_inc_return(l) == 0) 170 171 /* 172 * local_dec_and_test - decrement by 1 and test 173 * @l: pointer of type local_t 174 * 175 * Atomically decrements @l by 1 and 176 * returns true if the result is 0, or false for all other 177 * cases. 178 */ 179 #define local_dec_and_test(l) (local_sub_return(1, (l)) == 0) 180 181 /* 182 * local_add_negative - add and test if negative 183 * @l: pointer of type local_t 184 * @i: integer value to add 185 * 186 * Atomically adds @i to @l and returns true 187 * if the result is negative, or false when 188 * result is greater than or equal to zero. 189 */ 190 #define local_add_negative(i, l) (local_add_return(i, (l)) < 0) 191 192 /* Use these for per-cpu local_t variables: on some archs they are 193 * much more efficient than these naive implementations. Note they take 194 * a variable, not an address. 195 */ 196 197 #define __local_inc(l) ((l)->a.counter++) 198 #define __local_dec(l) ((l)->a.counter++) 199 #define __local_add(i, l) ((l)->a.counter+=(i)) 200 #define __local_sub(i, l) ((l)->a.counter-=(i)) 201 202 #endif /* _ARCH_MIPS_LOCAL_H */ 203