diff options
Diffstat (limited to 'kern/atomic.h')
| -rw-r--r-- | kern/atomic.h | 107 |
1 files changed, 51 insertions, 56 deletions
diff --git a/kern/atomic.h b/kern/atomic.h index d37a28b..1172009 100644 --- a/kern/atomic.h +++ b/kern/atomic.h @@ -1,4 +1,5 @@ /* + * Copyright (c) 2018 Richard Braun. * Copyright (c) 2017 Agustina Arzille. * * This program is free software: you can redistribute it and/or modify @@ -17,6 +18,12 @@ * * Type-generic memory-model aware atomic operations. * + * For portability reasons, this interface restricts atomic operation + * sizes to 32-bit and 64-bit. + * + * Some configurations may not support 64-bit operations. Check if the + * ATOMIC_HAVE_64B_OPS macro is defined to find out. + * * TODO Replace mentions of "memory barriers" throughout the code with * C11 memory model terminology. */ @@ -26,43 +33,25 @@ #include <stdbool.h> -#include <kern/macros.h> #include <machine/atomic.h> /* * Supported memory orders. */ -#define ATOMIC_RELAXED __ATOMIC_RELAXED -#define ATOMIC_CONSUME __ATOMIC_CONSUME -#define ATOMIC_ACQUIRE __ATOMIC_ACQUIRE -#define ATOMIC_RELEASE __ATOMIC_RELEASE -#define ATOMIC_ACQ_REL __ATOMIC_ACQ_REL -#define ATOMIC_SEQ_CST __ATOMIC_SEQ_CST - -/* - * Type-generic atomic operations. - */ -#define atomic_fetch_add(ptr, val, mo) __atomic_fetch_add(ptr, val, mo) - -#define atomic_fetch_sub(ptr, val, mo) __atomic_fetch_sub(ptr, val, mo) - -#define atomic_fetch_and(ptr, val, mo) __atomic_fetch_and(ptr, val, mo) - -#define atomic_fetch_or(ptr, val, mo) __atomic_fetch_or(ptr, val, mo) - -#define atomic_fetch_xor(ptr, val, mo) __atomic_fetch_xor(ptr, val, mo) - -#define atomic_add(ptr, val, mo) (void)__atomic_add_fetch(ptr, val, mo) - -#define atomic_sub(ptr, val, mo) (void)__atomic_sub_fetch(ptr, val, mo) - -#define atomic_and(ptr, val, mo) (void)__atomic_and_fetch(ptr, val, mo) +#define ATOMIC_RELAXED __ATOMIC_RELAXED +#define ATOMIC_CONSUME __ATOMIC_CONSUME +#define ATOMIC_ACQUIRE __ATOMIC_ACQUIRE +#define ATOMIC_RELEASE __ATOMIC_RELEASE +#define ATOMIC_ACQ_REL __ATOMIC_ACQ_REL +#define ATOMIC_SEQ_CST __ATOMIC_SEQ_CST -#define atomic_or(ptr, val, mo) (void)__atomic_or_fetch(ptr, val, mo) +#include <kern/atomic_i.h> -#define atomic_xor(ptr, val, mo) (void)__atomic_xor_fetch(ptr, val, mo) +#define atomic_load(ptr, memorder) \ +((typeof(*(ptr)))atomic_select(ptr, load)(ptr, memorder)) -#define atomic_swap(ptr, val, mo) __atomic_exchange_n(ptr, val, mo) +#define atomic_store(ptr, val, memorder) \ +atomic_select(ptr, store)(ptr, val, memorder) /* * For compare-and-swap, deviate a little from the standard, and only @@ -73,37 +62,43 @@ * because atomic CAS is typically used in a loop. However, if a different * code path is taken on failure (rather than retrying), then the user * should be aware that a memory fence might be necessary. - * - * Finally, although a local variable isn't strictly needed for the new - * value, some compilers seem to have trouble when all parameters don't - * have the same type. */ -#define atomic_cas(ptr, oval, nval, mo) \ -MACRO_BEGIN \ - typeof(*(ptr)) oval_, nval_; \ - \ - oval_ = (oval); \ - nval_ = (nval); \ - __atomic_compare_exchange_n(ptr, &oval_, nval_, false, \ - mo, ATOMIC_RELAXED); \ - oval_; \ -MACRO_END +#define atomic_cas(ptr, oval, nval, memorder) \ +((typeof(*(ptr)))atomic_select(ptr, cas)(ptr, oval, nval, memorder)) -/* - * Some architectures may need specific definitions for loads and stores, - * in order to prevent the compiler from emitting unsupported instructions. - * As such, only define these if the architecture-specific part of the - * module didn't already. - */ +#define atomic_swap(ptr, val, memorder) \ +((typeof(*(ptr)))atomic_select(ptr, swap)(ptr, val, memorder)) + +#define atomic_fetch_add(ptr, val, memorder) \ +((typeof(*(ptr)))atomic_select(ptr, fetch_add)(ptr, val, memorder)) + +#define atomic_fetch_sub(ptr, val, memorder) \ +((typeof(*(ptr)))atomic_select(ptr, fetch_sub)(ptr, val, memorder)) + +#define atomic_fetch_and(ptr, val, memorder) \ +((typeof(*(ptr)))atomic_select(ptr, fetch_and)(ptr, val, memorder)) + +#define atomic_fetch_or(ptr, val, memorder) \ +((typeof(*(ptr)))atomic_select(ptr, fetch_or)(ptr, val, memorder)) + +#define atomic_fetch_xor(ptr, val, memorder) \ +((typeof(*(ptr)))atomic_select(ptr, fetch_xor)(ptr, val, memorder)) + +#define atomic_add(ptr, val, memorder) \ +atomic_select(ptr, add)(ptr, val, memorder) + +#define atomic_sub(ptr, val, memorder) \ +atomic_select(ptr, sub)(ptr, val, memorder) + +#define atomic_and(ptr, val, memorder) \ +atomic_select(ptr, and)(ptr, val, memorder) -#ifndef ATOMIC_ARCH_SPECIFIC_LOAD -#define atomic_load(ptr, mo) __atomic_load_n(ptr, mo) -#endif +#define atomic_or(ptr, val, memorder) \ +atomic_select(ptr, or)(ptr, val, memorder) -#ifndef ATOMIC_ARCH_SPECIFIC_STORE -#define atomic_store(ptr, val, mo) __atomic_store_n(ptr, val, mo) -#endif +#define atomic_xor(ptr, val, memorder) \ +atomic_select(ptr, xor)(ptr, val, memorder) -#define atomic_fence(mo) __atomic_thread_fence(mo) +#define atomic_fence(memorder) __atomic_thread_fence(memorder) #endif /* KERN_ATOMIC_H */ |