1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ALPHA_LOCAL_H 3 #define _ALPHA_LOCAL_H 4 5 #include <linux/percpu.h> 6 #include <linux/atomic.h> 7 8 typedef struct 9 { 10 atomic_long_t a; 11 } local_t; 12 13 #define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) } 14 #define local_read(l) atomic_long_read(&(l)->a) 15 #define local_set(l,i) atomic_long_set(&(l)->a, (i)) 16 #define local_inc(l) atomic_long_inc(&(l)->a) 17 #define local_dec(l) atomic_long_dec(&(l)->a) 18 #define local_add(i,l) atomic_long_add((i),(&(l)->a)) 19 #define local_sub(i,l) atomic_long_sub((i),(&(l)->a)) 20 21 static __inline__ long local_add_return(long i, local_t * l) 22 { 23 long temp, result; 24 __asm__ __volatile__( 25 "1: ldq_l %0,%1\n" 26 " addq %0,%3,%2\n" 27 " addq %0,%3,%0\n" 28 " stq_c %0,%1\n" 29 " beq %0,2f\n" 30 ".subsection 2\n" 31 "2: br 1b\n" 32 ".previous" 33 :"=&r" (temp), "=m" (l->a.counter), "=&r" (result) 34 :"Ir" (i), "m" (l->a.counter) : "memory"); 35 return result; 36 } 37 38 static __inline__ long local_sub_return(long i, local_t * l) 39 { 40 long temp, result; 41 __asm__ __volatile__( 42 "1: ldq_l %0,%1\n" 43 " subq %0,%3,%2\n" 44 " subq %0,%3,%0\n" 45 " stq_c %0,%1\n" 46 " beq %0,2f\n" 47 ".subsection 2\n" 48 "2: br 1b\n" 49 ".previous" 50 :"=&r" (temp), "=m" (l->a.counter), "=&r" (result) 51 :"Ir" (i), "m" (l->a.counter) : "memory"); 52 return result; 53 } 54 55 #define local_cmpxchg(l, o, n) \ 56 (cmpxchg_local(&((l)->a.counter), (o), (n))) 57 #define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n))) 58 59 /** 60 * local_add_unless - add unless the number is a given value 61 * @l: pointer of type local_t 62 * @a: the amount to add to l... 63 * @u: ...unless l is equal to u. 64 * 65 * Atomically adds @a to @l, so long as it was not @u. 66 * Returns non-zero if @l was not @u, and zero otherwise. 67 */ 68 #define local_add_unless(l, a, u) \ 69 ({ \ 70 long c, old; \ 71 c = local_read(l); \ 72 for (;;) { \ 73 if (unlikely(c == (u))) \ 74 break; \ 75 old = local_cmpxchg((l), c, c + (a)); \ 76 if (likely(old == c)) \ 77 break; \ 78 c = old; \ 79 } \ 80 c != (u); \ 81 }) 82 #define local_inc_not_zero(l) local_add_unless((l), 1, 0) 83 84 #define local_add_negative(a, l) (local_add_return((a), (l)) < 0) 85 86 #define local_dec_return(l) local_sub_return(1,(l)) 87 88 #define local_inc_return(l) local_add_return(1,(l)) 89 90 #define local_sub_and_test(i,l) (local_sub_return((i), (l)) == 0) 91 92 #define local_inc_and_test(l) (local_add_return(1, (l)) == 0) 93 94 #define local_dec_and_test(l) (local_sub_return(1, (l)) == 0) 95 96 /* Verify if faster than atomic ops */ 97 #define __local_inc(l) ((l)->a.counter++) 98 #define __local_dec(l) ((l)->a.counter++) 99 #define __local_add(i,l) ((l)->a.counter+=(i)) 100 #define __local_sub(i,l) ((l)->a.counter-=(i)) 101 102 #endif /* _ALPHA_LOCAL_H */ 103