1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_GENERIC_LOCAL64_H 3 #define _ASM_GENERIC_LOCAL64_H 4 5 #include <linux/percpu.h> 6 #include <asm/types.h> 7 8 /* 9 * A signed long type for operations which are atomic for a single CPU. 10 * Usually used in combination with per-cpu variables. 11 * 12 * This is the default implementation, which uses atomic64_t. Which is 13 * rather pointless. The whole point behind local64_t is that some processors 14 * can perform atomic adds and subtracts in a manner which is atomic wrt IRQs 15 * running on this CPU. local64_t allows exploitation of such capabilities. 16 */ 17 18 /* Implement in terms of atomics. */ 19 20 #if BITS_PER_LONG == 64 21 22 #include <asm/local.h> 23 24 typedef struct { 25 local_t a; 26 } local64_t; 27 28 #define LOCAL64_INIT(i) { LOCAL_INIT(i) } 29 30 #define local64_read(l) local_read(&(l)->a) 31 #define local64_set(l,i) local_set((&(l)->a),(i)) 32 #define local64_inc(l) local_inc(&(l)->a) 33 #define local64_dec(l) local_dec(&(l)->a) 34 #define local64_add(i,l) local_add((i),(&(l)->a)) 35 #define local64_sub(i,l) local_sub((i),(&(l)->a)) 36 37 #define local64_sub_and_test(i, l) local_sub_and_test((i), (&(l)->a)) 38 #define local64_dec_and_test(l) local_dec_and_test(&(l)->a) 39 #define local64_inc_and_test(l) local_inc_and_test(&(l)->a) 40 #define local64_add_negative(i, l) local_add_negative((i), (&(l)->a)) 41 #define local64_add_return(i, l) local_add_return((i), (&(l)->a)) 42 #define local64_sub_return(i, l) local_sub_return((i), (&(l)->a)) 43 #define local64_inc_return(l) local_inc_return(&(l)->a) 44 45 static inline s64 local64_cmpxchg(local64_t *l, s64 old, s64 new) 46 { 47 return local_cmpxchg(&l->a, old, new); 48 } 49 50 static inline bool local64_try_cmpxchg(local64_t *l, s64 *old, s64 new) 51 { 52 return local_try_cmpxchg(&l->a, (long *)old, new); 53 } 54 55 #define local64_xchg(l, n) local_xchg((&(l)->a), (n)) 56 #define local64_add_unless(l, _a, u) local_add_unless((&(l)->a), (_a), (u)) 57 #define local64_inc_not_zero(l) local_inc_not_zero(&(l)->a) 58 59 /* Non-atomic variants, ie. preemption disabled and won't be touched 60 * in interrupt, etc. Some archs can optimize this case well. */ 61 #define __local64_inc(l) local64_set((l), local64_read(l) + 1) 62 #define __local64_dec(l) local64_set((l), local64_read(l) - 1) 63 #define __local64_add(i,l) local64_set((l), local64_read(l) + (i)) 64 #define __local64_sub(i,l) local64_set((l), local64_read(l) - (i)) 65 66 #else /* BITS_PER_LONG != 64 */ 67 68 #include <linux/atomic.h> 69 70 /* Don't use typedef: don't want them to be mixed with atomic_t's. */ 71 typedef struct { 72 atomic64_t a; 73 } local64_t; 74 75 #define LOCAL64_INIT(i) { ATOMIC_LONG_INIT(i) } 76 77 #define local64_read(l) atomic64_read(&(l)->a) 78 #define local64_set(l,i) atomic64_set((&(l)->a),(i)) 79 #define local64_inc(l) atomic64_inc(&(l)->a) 80 #define local64_dec(l) atomic64_dec(&(l)->a) 81 #define local64_add(i,l) atomic64_add((i),(&(l)->a)) 82 #define local64_sub(i,l) atomic64_sub((i),(&(l)->a)) 83 84 #define local64_sub_and_test(i, l) atomic64_sub_and_test((i), (&(l)->a)) 85 #define local64_dec_and_test(l) atomic64_dec_and_test(&(l)->a) 86 #define local64_inc_and_test(l) atomic64_inc_and_test(&(l)->a) 87 #define local64_add_negative(i, l) atomic64_add_negative((i), (&(l)->a)) 88 #define local64_add_return(i, l) atomic64_add_return((i), (&(l)->a)) 89 #define local64_sub_return(i, l) atomic64_sub_return((i), (&(l)->a)) 90 #define local64_inc_return(l) atomic64_inc_return(&(l)->a) 91 92 #define local64_cmpxchg(l, o, n) atomic64_cmpxchg((&(l)->a), (o), (n)) 93 #define local64_try_cmpxchg(l, po, n) atomic64_try_cmpxchg((&(l)->a), (po), (n)) 94 #define local64_xchg(l, n) atomic64_xchg((&(l)->a), (n)) 95 #define local64_add_unless(l, _a, u) atomic64_add_unless((&(l)->a), (_a), (u)) 96 #define local64_inc_not_zero(l) atomic64_inc_not_zero(&(l)->a) 97 98 /* Non-atomic variants, ie. preemption disabled and won't be touched 99 * in interrupt, etc. Some archs can optimize this case well. */ 100 #define __local64_inc(l) local64_set((l), local64_read(l) + 1) 101 #define __local64_dec(l) local64_set((l), local64_read(l) - 1) 102 #define __local64_add(i,l) local64_set((l), local64_read(l) + (i)) 103 #define __local64_sub(i,l) local64_set((l), local64_read(l) - (i)) 104 105 #endif /* BITS_PER_LONG != 64 */ 106 107 #endif /* _ASM_GENERIC_LOCAL64_H */ 108