free_timer
(void) heap_for_each(ctx->timers, free_timer, NULL);
static void free_timer(void *, void *);
callout_init(&cb->free_timer, 0);
callout_reset(&cb->free_timer, 10 * hz, tcplike_send_term, (void *)cb);
callout_init(&ccb->free_timer, 0);
callout_reset(&cb->free_timer, 10 * hz, tcplike_recv_term, (void *)cb);
struct callout free_timer;
struct callout free_timer;