diff options
Diffstat (limited to 'include/asm-powerpc/system.h')
| -rw-r--r-- | include/asm-powerpc/system.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/include/asm-powerpc/system.h b/include/asm-powerpc/system.h index b6d330fe8ed3..4b41deaa8d8d 100644 --- a/include/asm-powerpc/system.h +++ b/include/asm-powerpc/system.h @@ -53,6 +53,15 @@ #define smp_read_barrier_depends() do { } while(0) #endif /* CONFIG_SMP */ +/* + * This is a barrier which prevents following instructions from being + * started until the value of the argument x is known. For example, if + * x is a variable loaded from memory, this prevents following + * instructions from being executed until the load has been performed. + */ +#define data_barrier(x) \ + asm volatile("twi 0,%0,0; isync" : : "r" (x) : "memory"); + struct task_struct; struct pt_regs; |