static void get_fb_info(struct vmm_fb_info *fb_info)
{
if (!fb_info)
return;
arch_atomic_add(&fb_info->count, 1);
}
// Atomic subtraction. Returns false if the counter drops to zero.
inline bool sub (integer_t decrement)
{
#if defined ZMQ_ATOMIC_COUNTER_WINDOWS
LONG delta = - ((LONG) decrement);
integer_t old = InterlockedExchangeAdd ((LONG*) &value, delta);
return old - decrement != 0;
#elif defined ZMQ_ATOMIC_INTRINSIC
integer_t nv = __atomic_sub_fetch(&value, decrement, __ATOMIC_ACQ_REL);
return nv != 0;
#elif defined ZMQ_ATOMIC_COUNTER_ATOMIC_H
int32_t delta = - ((int32_t) decrement);
integer_t nv = atomic_add_32_nv (&value, delta);
return nv != 0;
#elif defined ZMQ_ATOMIC_COUNTER_TILE
int32_t delta = - ((int32_t) decrement);
integer_t nv = arch_atomic_add (&value, delta);
return nv != 0;
#elif defined ZMQ_ATOMIC_COUNTER_X86
integer_t oldval = -decrement;
volatile integer_t *val = &value;
__asm__ volatile ("lock; xaddl %0,%1"
: "=r" (oldval), "=m" (*val)
: "0" (oldval), "m" (*val)
: "cc", "memory");
return oldval != decrement;
#elif defined ZMQ_ATOMIC_COUNTER_ARM
integer_t old_value, flag, tmp;
__asm__ volatile (
" dmb sy\n\t"
"1: ldrex %0, [%5]\n\t"
" sub %2, %0, %4\n\t"
" strex %1, %2, [%5]\n\t"
" teq %1, #0\n\t"
" bne 1b\n\t"
" dmb sy\n\t"
: "=&r"(old_value), "=&r"(flag), "=&r"(tmp), "+Qo"(value)
: "Ir"(decrement), "r"(&value)
: "cc");
return old_value - decrement != 0;
#elif defined ZMQ_ATOMIC_COUNTER_MUTEX
sync.lock ();
value -= decrement;
bool result = value ? true : false;
sync.unlock ();
return result;
#else
#error atomic_counter is not implemented for this platform
#endif
}
