ktrace_node
tracenode = kmalloc(sizeof(struct ktrace_node), M_KTRACE,
ktrdestroy(struct ktrace_node **tracenodep)
void ktrdestroy(struct ktrace_node **);
struct ktrace_node *ktrinherit(struct ktrace_node *);
typedef struct ktrace_node *ktrace_node_t;
struct ktrace_node;
struct ktrace_node *p_tracenode; /* Trace to vnode. */
struct ktrace_node ktrace_node;
if (kread(p->p_tracenode, &ktrace_node, sizeof (ktrace_node)))
vtrans(ktrace_node.kn_vp, NULL, TRACE, FREAD|FWRITE, 0);