On 19.07.2022 15:52, Stefano Garzarella wrote: > On Mon, Jul 18, 2022 at 08:19:06AM +0000, Arseniy Krasnov wrote: >> This adds test to check, that when poll() returns POLLIN and >> POLLRDNORM bits, next read call won't block. >> >> Signed-off-by: Arseniy Krasnov <AVKrasnov@xxxxxxxxxxxxxx> >> --- >> tools/testing/vsock/vsock_test.c | 90 ++++++++++++++++++++++++++++++++ >> 1 file changed, 90 insertions(+) >> >> diff --git a/tools/testing/vsock/vsock_test.c b/tools/testing/vsock/vsock_test.c >> index dc577461afc2..8e394443eaf6 100644 >> --- a/tools/testing/vsock/vsock_test.c >> +++ b/tools/testing/vsock/vsock_test.c >> @@ -18,6 +18,7 @@ >> #include <sys/socket.h> >> #include <time.h> >> #include <sys/mman.h> >> +#include <poll.h> >> >> #include "timeout.h" >> #include "control.h" >> @@ -596,6 +597,90 @@ static void test_seqpacket_invalid_rec_buffer_server(const struct test_opts *opt >> close(fd); >> } >> >> +static void test_stream_poll_rcvlowat_server(const struct test_opts *opts) >> +{ >> +#define RCVLOWAT_BUF_SIZE 128 >> + int fd; >> + int i; >> + >> + fd = vsock_stream_accept(VMADDR_CID_ANY, 1234, NULL); >> + if (fd < 0) { >> + perror("accept"); >> + exit(EXIT_FAILURE); >> + } >> + >> + /* Send 1 byte. */ >> + send_byte(fd, 1, 0); >> + >> + control_writeln("SRVSENT"); >> + >> + /* Just empirically delay value. */ >> + sleep(4); > > Why we need this sleep()? Purpose of sleep() is to move client in state, when it has 1 byte of rx data and poll() won't wake. For example: client: server: waits for "SRVSENT" send 1 byte send "SRVSENT" poll() sleep ... poll sleeps ... send rest of data poll wake up I think, without sleep there is chance, that client enters poll() when whole data from server is already received, thus test will be useless(it just tests poll()). May be i can remove "SRVSENT" as sleep is enough. >