linux/include/linux/blk-cgroup.h
/**
 * blkg_try_get - try and get a blkg reference
 * @blkg: blkg to get
 *
 * This is for use when doing an RCU lookup of the blkg.  We may be in the midst
 * of freeing this blkg, so we can only use it if the refcnt is not zero.
 */
try and get a blkg reference
@blkg: blkg to get

This is for use when doing an RCU lookup of the blkg.  We may be in the midst
of freeing this blkg, so we can only use it if the refcnt is not zero.
try and get a blkg reference @blkg : blkg to get This is for use when doing an RCU lookup of the blkg . We may be in the midst of freeing this blkg so we can only use it if the refcnt is not zero .
static inline struct blkcg_gq *blkg_try_get(struct blkcg_gq *blkg)
{
	if (atomic_inc_not_zero(&blkg->refcnt))
		return blkg;
	return NULL;
}
static inline struct blkcg_gq * blkg_try_get ( struct blkcg_gq * blkg ) { if ( atomic_inc_not_zero ( & blkg -> refcnt ) ) return blkg ; return NULL ; }
blkg_try_get - try and get a blkg reference
 @blkg: blkg to get
blkg_try_get - try and get a blkg reference @blkg : blkg to get