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 static __inline__ long local_cmpxchg(local_t *l, long old, long new) 56 { 57 return cmpxchg_local(&l->a.counter, old, new); 58 } 59 60 static __inline__ bool local_try_cmpxchg(local_t *l, long *old, long new) 61 { 62 return try_cmpxchg_local(&l->a.counter, (s64 *)old, new); 63 } 64 65 #define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n))) 66 67 /** 68 * local_add_unless - add unless the number is already a given value 69 * @l: pointer of type local_t 70 * @a: the amount to add to l... 71 * @u: ...unless l is equal to u. 72 * 73 * Atomically adds @a to @l, if @v was not already @u. 74 * Returns true if the addition was done. 75 */ 76 static __inline__ bool 77 local_add_unless(local_t *l, long a, long u) 78 { 79 long c = local_read(l); 80 81 do { 82 if (unlikely(c == u)) 83 return false; 84 } while (!local_try_cmpxchg(l, &c, c + a)); 85 86 return true; 87 } 88 89 #define local_inc_not_zero(l) local_add_unless((l), 1, 0) 90 91 #define local_add_negative(a, l) (local_add_return((a), (l)) < 0) 92 93 #define local_dec_return(l) local_sub_return(1,(l)) 94 95 #define local_inc_return(l) local_add_return(1,(l)) 96 97 #define local_sub_and_test(i,l) (local_sub_return((i), (l)) == 0) 98 99 #define local_inc_and_test(l) (local_add_return(1, (l)) == 0) 100 101 #define local_dec_and_test(l) (local_sub_return(1, (l)) == 0) 102 103 /* Verify if faster than atomic ops */ 104 #define __local_inc(l) ((l)->a.counter++) 105 #define __local_dec(l) ((l)->a.counter++) 106 #define __local_add(i,l) ((l)->a.counter+=(i)) 107 #define __local_sub(i,l) ((l)->a.counter-=(i)) 108 109 #endif /* _ALPHA_LOCAL_H */ 110