callfd 32 tools/virtio/ringtest/main.c static int callfd = -1; callfd 68 tools/virtio/ringtest/main.c notify(callfd); callfd 73 tools/virtio/ringtest/main.c wait_for_notify(callfd); callfd 304 tools/virtio/ringtest/main.c callfd = eventfd(0, 0); callfd 305 tools/virtio/ringtest/main.c assert(callfd >= 0);