NAME
atomic_add_int,
atomic_add_int_nv,
atomic_add_long,
atomic_add_long_nv —
atomic addition operations
SYNOPSIS
#include
<sys/atomic.h>
void
atomic_add_int(volatile
unsigned int *p, unsigned
int v);
unsigned int
atomic_add_int_nv(volatile
unsigned int *p, unsigned
int v);
void
atomic_add_long(volatile
unsigned long *p,
unsigned long v);
unsigned long
atomic_add_long_nv(volatile
unsigned long *p,
unsigned long v);
DESCRIPTION
The atomic_add set of functions provide an interface for atomically performing add and add-and-fetch operations with respect to interrupts and multiple processors in the system.
The value referenced by the pointer p is incremented by the value v.
CONTEXT
atomic_add_int(),
atomic_add_int_nv(),
atomic_add_long(), and
atomic_add_long_nv() can all be called during
autoconf, from process context, or from interrupt context.
RETURN VALUES
atomic_add_int and
atomic_add_long perform the addition without
returning any knowledge of the value at p.
atomic_add_int_nv and
atomic_add_long_nv return the value at
p after the addition was performed.
SEE ALSO
HISTORY
The atomic_add functions first appeared in NetBSD 5.0 and OpenBSD 5.5.