Re: [PATCH net 2/4] net/udpgso_bench_tx: options to exercise TX CMSG

From: Willem de Bruijn
Date: Thu May 23 2019 - 17:49:25 EST


On Thu, May 23, 2019 at 5:11 PM Fred Klassen <fklassen@xxxxxxxxxxx> wrote:
>
> This enhancement adds options that facilitate load testing with
> additional TX CMSG options, and to optionally print results of
> various send CMSG operations.
>
> These options are especially useful in isolating situations
> where error-queue messages are lost when combined with other
> CMSG operations (e.g. SO_ZEROCOPY).
>
> New options:
>
> -T - add TX CMSG that requests TX software timestamps
> -H - similar to -T except request TX hardware timestamps
> -q - add IP_TOS/IPV6_TCLASS TX CMSG
> -P - call poll() before reading error queue
> -v - print detailed results
>
> Fixes: 3a687bef148d ("selftests: udp gso benchmark")

This is not a fix, but an extension. Fixes tags help with backporting
to stable kernels. There is something to be said to backport the main
change and support SO_TIMESTAMPING + UDP_GSO on older kernels,
especially since it is very concise. But the tests should probably be
in a separate patch set targeting net-next.


> Signed-off-by: Fred Klassen <fklassen@xxxxxxxxxxx>
> ---
> tools/testing/selftests/net/udpgso_bench_tx.c | 290 ++++++++++++++++++++++++--
> 1 file changed, 273 insertions(+), 17 deletions(-)
>
> diff --git a/tools/testing/selftests/net/udpgso_bench_tx.c b/tools/testing/selftests/net/udpgso_bench_tx.c
> index 4074538b5df5..a900f016b9e7 100644
> --- a/tools/testing/selftests/net/udpgso_bench_tx.c
> +++ b/tools/testing/selftests/net/udpgso_bench_tx.c
> @@ -5,6 +5,8 @@
> #include <arpa/inet.h>
> #include <errno.h>
> #include <error.h>
> +#include <linux/errqueue.h>
> +#include <linux/net_tstamp.h>
> #include <netinet/if_ether.h>
> #include <netinet/in.h>
> #include <netinet/ip.h>
> @@ -19,6 +21,7 @@
> #include <string.h>
> #include <sys/socket.h>
> #include <sys/time.h>
> +#include <sys/poll.h>
> #include <sys/types.h>
> #include <unistd.h>
>
> @@ -34,6 +37,10 @@
> #define SO_ZEROCOPY 60
> #endif
>
> +#ifndef SO_EE_ORIGIN_ZEROCOPY
> +#define SO_EE_ORIGIN_ZEROCOPY 5
> +#endif
> +
> #ifndef MSG_ZEROCOPY
> #define MSG_ZEROCOPY 0x4000000
> #endif
> @@ -48,9 +55,14 @@ static uint16_t cfg_mss;
> static int cfg_payload_len = (1472 * 42);
> static int cfg_port = 8000;
> static int cfg_runtime_ms = -1;
> +static bool cfg_poll;
> static bool cfg_segment;
> static bool cfg_sendmmsg;
> static bool cfg_tcp;
> +static uint32_t cfg_tx_ts = SOF_TIMESTAMPING_TX_SOFTWARE;
> +static bool cfg_tx_tstamp;
> +static uint32_t cfg_tos;
> +static bool cfg_verbose;
> static bool cfg_zerocopy;
> static int cfg_msg_nr;
> static uint16_t cfg_gso_size;
> @@ -58,6 +70,10 @@ static uint16_t cfg_gso_size;
> static socklen_t cfg_alen;
> static struct sockaddr_storage cfg_dst_addr;
>
> +struct my_scm_timestamping {
> + struct timespec ts[3];
> +};
> +

This and the above should not be needed if including <linux/errqueue.h>

It may be absent if relying on the host header files, but the
kselftest build system should correctly use the files from the kernel
source tree.

> static bool interrupted;
> static char buf[NUM_PKT][ETH_MAX_MTU];
>
> @@ -89,20 +105,20 @@ static int set_cpu(int cpu)
>
> static void setup_sockaddr(int domain, const char *str_addr, void *sockaddr)
> {
> - struct sockaddr_in6 *addr6 = (void *) sockaddr;
> - struct sockaddr_in *addr4 = (void *) sockaddr;
> + struct sockaddr_in6 *addr6 = (void *)sockaddr;
> + struct sockaddr_in *addr4 = (void *)sockaddr;
>
> switch (domain) {
> case PF_INET:
> addr4->sin_family = AF_INET;
> addr4->sin_port = htons(cfg_port);
> - if (inet_pton(AF_INET, str_addr, &(addr4->sin_addr)) != 1)
> + if (inet_pton(AF_INET, str_addr, &addr4->sin_addr) != 1)
> error(1, 0, "ipv4 parse error: %s", str_addr);
> break;
> case PF_INET6:
> addr6->sin6_family = AF_INET6;
> addr6->sin6_port = htons(cfg_port);
> - if (inet_pton(AF_INET6, str_addr, &(addr6->sin6_addr)) != 1)
> + if (inet_pton(AF_INET6, str_addr, &addr6->sin6_addr) != 1)

Please do not include style changes like these. Try to minimize
changes required to add the new feature.