test_iperf3() is a pretty inscrutable mess of nested background processes.
It has a number of ugly sleeps needed to wait for things to complete.

Rewrite it to be cleaner:
  * Use the construct (a & b & wait) to run 'a' and 'b' in parallel, but
    then wait for them both to complete before continuing
  * This allows us to wait for both the server and client to finish, rather
    than sleeping
  * Use jq to do all the math we need to get the final result, rather than
    jq followed by some complicated 'bc' mangling

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Currently all the throughput tests are run for 30s.  This is reflected in
both the actual parameters given to the iperf commands, but also in the
matching sleeps in test_iperf3.

Allow this to be adjusted more easily with a new parameter to test_iperf3.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
[sbrivio: Reflect new parameter in comment to test_iperf3()]
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

These two commands in the DSL to run an iperf client and server are always
used together, and some of the parameters must match between them.  The
iperf3s must also be run more or less immediately after iperf3c, since
iperf3c will run a client in the background after a sleep and requires a
server to be running before it will work.

A bunch of things can be made cleaner if we make a single DSL command that
runs both sides of the test.  For now make the combined command work
exactly like the two commands together did, warts and all.

This does lose the ability for the DSL scripts to give additional options
to the iperf3 server, but we weren't using that anyway.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Currently in at least some of the testcases we kill qemu processes we're
done with by issuing a Control-C to the tmux panel it's running in.  That
makes things harder as we try to move towards allowing "headless" testing
without tmux.

So, instead always use an explicit kill on a pid derived from a pidfile
for killing qemu.  Note that we don't need to remove the pidfiles
afterwards, because qemu does that itself when terminated.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

For the passt and passt_in_ns tests we have a "shutdown" testcase that
checks for any errors from the passt process we were using (including
valgrind warnings).  Do the same for pasta tests, so that we catch any
error codes from the pasta process.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

The "valgrind" test cases are designed to pick up errors reported when
passt is running under valgrind.  But what it actually does is just kill
the passt process, then see if it had a non-zero exit code.  That means it
will equally well pick up any other problems which caused passt to exit
with an error status: either something detected within passt or as a result
of passt being killed by an unexpected signal.

The fact that the "valgrind" test is actually responsible for shutting down
the passt process is non-obvious and can lead to problems when selectively
running tests during debugging.

Rename the "valgrind" tests to "shutdown" tests and run it regardless of
whether we're using valgrind or not.  This allows us to remove an ugly
speacial case in the passt_in_ns teardown code.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Currently the build tests and distro tests share a common setup function.
That works for now, but changes we want to make will mean they need
slightly different setup, so split the setup functions in preparation.

Currently, neither build nor distro tests have any teardown function.
Again, future changes are going to mean we need to do some teardown, so
create some empty for now teardown functions in preparation.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

The DEMO_XTERM and CI_XTERM variables defined in test/lib/term aren't used
anywhere.  Remove them.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

The iperf based test commands create a bunch of .bw and .pid files for
each iperf client and server.  The server side .bw files are cleaned
up afterwards, but the pid files are not, and none of the client side
files are cleaned up.  The latter doesn't really matter when the
client is run on ephemeral guests, but sometimes we run it in a
namespace that shares the filesystem with the host.

Clean up all of these files after the tests.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Before starting the guests, these tests configure addresses in a pasta
namespace using dhclient.  However, because it's a user namespace, it's
not running as "real" root and can't write to the dhclient pid file.
This doesn't stop it working, but causes an ugly error message which we
can avoid by using the --no-pid option.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>