The tx and rx test programs are used in a couple of test scripts including "udpgro_bench.sh". Taking this as an example, when the rx/tx programs are invoked subsequently, there is a chance that the rx one is not ready to accept socket connections. This racing bug could fail the test with at least one of the following:
./udpgso_bench_tx: connect: Connection refused ./udpgso_bench_tx: sendmsg: Connection refused ./udpgso_bench_tx: write: Connection refused
This change addresses this by adding routines that retry the socket operations with an exponential back off algorithm from 100ms to 2s.
Fixes: 3a687bef148d ("selftests: udp gso benchmark") Signed-off-by: Andrei Gherzan andrei.gherzan@canonical.com --- tools/testing/selftests/net/udpgso_bench_tx.c | 57 +++++++++++++------ 1 file changed, 41 insertions(+), 16 deletions(-)
diff --git a/tools/testing/selftests/net/udpgso_bench_tx.c b/tools/testing/selftests/net/udpgso_bench_tx.c index f1fdaa270291..4dea9ee7eb46 100644 --- a/tools/testing/selftests/net/udpgso_bench_tx.c +++ b/tools/testing/selftests/net/udpgso_bench_tx.c @@ -53,6 +53,9 @@
#define NUM_PKT 100
+#define MAX_DELAY 2000000 +#define INIT_DELAY 100000 + static bool cfg_cache_trash; static int cfg_cpu = -1; static int cfg_connected = true; @@ -257,13 +260,18 @@ static void flush_errqueue(int fd, const bool do_poll) static int send_tcp(int fd, char *data) { int ret, done = 0, count = 0; + useconds_t delay = INIT_DELAY;
while (done < cfg_payload_len) { - ret = send(fd, data + done, cfg_payload_len - done, - cfg_zerocopy ? MSG_ZEROCOPY : 0); - if (ret == -1) - error(1, errno, "write"); - + delay = INIT_DELAY; + while ((ret = send(fd, data + done, cfg_payload_len - done, + cfg_zerocopy ? MSG_ZEROCOPY : 0)) == -1) { + usleep(delay); + if (delay < MAX_DELAY) + delay *= 2; + else + error(1, errno, "write"); + } done += ret; count++; } @@ -274,17 +282,23 @@ static int send_tcp(int fd, char *data) static int send_udp(int fd, char *data) { int ret, total_len, len, count = 0; + useconds_t delay = INIT_DELAY;
total_len = cfg_payload_len;
while (total_len) { len = total_len < cfg_mss ? total_len : cfg_mss;
- ret = sendto(fd, data, len, cfg_zerocopy ? MSG_ZEROCOPY : 0, - cfg_connected ? NULL : (void *)&cfg_dst_addr, - cfg_connected ? 0 : cfg_alen); - if (ret == -1) - error(1, errno, "write"); + delay = INIT_DELAY; + while ((ret = sendto(fd, data, len, cfg_zerocopy ? MSG_ZEROCOPY : 0, + cfg_connected ? NULL : (void *)&cfg_dst_addr, + cfg_connected ? 0 : cfg_alen)) == -1) { + usleep(delay); + if (delay < MAX_DELAY) + delay *= 2; + else + error(1, errno, "write"); + } if (ret != len) error(1, errno, "write: %uB != %uB\n", ret, len);
@@ -378,6 +392,7 @@ static int send_udp_segment(int fd, char *data) struct iovec iov = {0}; size_t msg_controllen; struct cmsghdr *cmsg; + useconds_t delay = INIT_DELAY; int ret;
iov.iov_base = data; @@ -401,9 +416,13 @@ static int send_udp_segment(int fd, char *data) msg.msg_name = (void *)&cfg_dst_addr; msg.msg_namelen = cfg_alen;
- ret = sendmsg(fd, &msg, cfg_zerocopy ? MSG_ZEROCOPY : 0); - if (ret == -1) - error(1, errno, "sendmsg"); + while ((ret = sendmsg(fd, &msg, cfg_zerocopy ? MSG_ZEROCOPY : 0)) == -1) { + usleep(delay); + if (delay < MAX_DELAY) + delay *= 2; + else + error(1, errno, "sendmsg"); + } if (ret != iov.iov_len) error(1, 0, "sendmsg: %u != %llu\n", ret, (unsigned long long)iov.iov_len); @@ -616,6 +635,7 @@ int main(int argc, char **argv) { unsigned long num_msgs, num_sends; unsigned long tnow, treport, tstop; + useconds_t delay = INIT_DELAY; int fd, i, val, ret;
parse_opts(argc, argv); @@ -648,9 +668,14 @@ int main(int argc, char **argv) } }
- if (cfg_connected && - connect(fd, (void *)&cfg_dst_addr, cfg_alen)) - error(1, errno, "connect"); + if (cfg_connected) + while (connect(fd, (void *)&cfg_dst_addr, cfg_alen)) { + usleep(delay); + if (delay < MAX_DELAY) + delay *= 2; + else + error(1, errno, "connect"); + }
if (cfg_segment) set_pmtu_discover(fd, cfg_family == PF_INET);