On 2023/3/16 17:19, Dmitry Kozlyuk wrote: > On Thu, Mar 16, 2023 at 4:11 AM fengchengwen <fengcheng...@huawei.com> wrote: >> Because we have no API to know the PMD whether impl specific ops, we could >> only knowed by invoking. >> Except above impl, I also consider the other two: >> 1. just invoke rte_eth_dev_priv_dump without previous printf("Device private >> info") and later error printf. >> and I think people may curious about the extra output without a prompt >> just like "Device private info". >> 2. use fmemopen (the below code), this way will perfect process the PMD >> which not imp ops. >> FILE *f = fmemopen(buf, max-size(e.g. 128KB)); >> ret = rte_eth_dev_priv_dump(port_id, f); >> if (ret == 0) { >> printf("Device private info:\n"); >> printf("%s", buf); >> } >> But the windows platform don't support fmemopen. >> >> Hope for more feedback. > > What if rte_eth_dev_priv_dump() was a documented no-op when "f == NULL"? > This can be implemented in ethdev layer: > 1) if not implemented, return ENOTSUP > 2) if f == NULL, return 0 > 3) else call PMD > Technically, even now a null device handle can be used, but this is > cumbersome and wastes resources for running the API twice.
Thanks your advise. V2 has sent which adopt Thomas's comment: printf("Device private info:\n"); ret = rte_eth_dev_priv_dump(port_id, stdout); if (ret == -ENOTSUP) printf(" none\n"); else if (ret < 0) fprintf(stderr, " Failed to dump private info with error (%d): %s\n", ret, strerror(-ret)); which seem simpler. > . >