passt/test/lib, branch 2022_10_26.f212044

test: Add log file tests for pasta plus corresponding layout and setup

2022-10-26T04:28:41+00:00

To test log files on a tmpfs mount, we need to unshare the mount
namespace, which means using a context for the passt pane is not
really practical at the moment, as we can't open a shell there, so
we would have to encapsulate all the commands under 'unshare -rUm',
plus the "inner" pasta command, running in turn a tcp_rr server.

It might be worth fixing this by e.g. detecting we are trying to
spawn an interactive shell and adding a special path in the context
setup with some form of stdin redirection -- I'm not sure it's doable
though.

For this reason, add a new layout, using a context only for the host
pane, while keeping the old command dispatch mechanism for the passt
pane.

We also need a new setup function that doesn't start pasta: we want
to start and restart it with different options.

Further, we need a 'pint' directive, to send an interrupt to the
passt pane: add that in lib/test.

All the tests before the one involving tmpfs and a detached mount
namespace were also tested with the context mechanism. To make an
eventual conversion easier, pass tcp_crr directly as a command on
pasta's command line where feasible.

While at it, fix the comment to the teardown_pasta() function.

The new test set can be semi-conveniently run as:

  ./run pasta_options/log_to_file

and it checks basic log creation, size of the log file after flooding
it with debug entries, rotations, and basic consistency after
rotations, on both an existing filesystem and a tmpfs, chosen as
it doesn't support collapsing data ranges via fallocate(), hence
triggering the fall-back mechanism for logging rotation.

Signed-off-by: Stefano Brivio

test: Add rudimentary support to run selected tests only

2022-10-14T15:38:24+00:00

To keep this simple, only support tests that have corresponding setup
and teardown functions implied by their path. For example:

  ./run passt/ndp

will trigger the 'passt' setup and teardown functions.

This is not really elegant, but it looks robust, and while David is
considering proper alternatives, it should be quite useful.

Signed-off-by: Stefano Brivio 
Reviewed-by: David Gibson

test: Remove unneccessary pane naming from layout_two_guests

2022-09-29T10:21:23+00:00

This loop goes through and gives a numeric label to each pane, even though
we name the panes properly shortly thereafter.  Looks like a leftover from
some earlier version.  Remove it.

Signed-off-by: David Gibson 
Signed-off-by: Stefano Brivio

test: Use --config-net for namespace setup

2022-09-29T10:21:13+00:00

The setup functions for passt_in_ns and two_guests perform some fairly slow
dhclient calls to configure the network in the namespace before starting
the guest.  This isn't really part of the tests, just necessary for the
operations later.

We can simplify and speed this up a bit by using pasta's '--config-net'
option to configure the networking for us.  As a bonus this means we have
at least a minimal test of the --config-net option itself.

Signed-off-by: David Gibson 
Signed-off-by: Stefano Brivio

test: More robust wait for pasta/passt to be ready

2022-09-29T10:21:07+00:00

When we start passt or pasta, it may take a short time to be ready to
handle packets, especially if running under valgrind.  We have a
number of semi-arbitrary fixed sleeps to account for this.

We can do this more robustly by exploiting the fact that pasta/passt
doesn't write its pidfile until it's ready to go, so if we wait for
the pidfile to be created, we can proceed with confidence.

Signed-off-by: David Gibson 
Signed-off-by: Stefano Brivio

test: Add wait_for() shell helper

2022-09-29T10:20:44+00:00

Add a shell helper function to wait for some command to succeed - typically
a test for something to be done by a background process.  Use it in the
context code which waits for the guest to respond to ssh-over-vsock
connections.

Signed-off-by: David Gibson 
Signed-off-by: Stefano Brivio

test/lib: Don't try to write to perf.js when running demos

2022-09-23T22:11:10+00:00

...it doesn't actually exist, and this error now causes the demo to
stop.

Signed-off-by: Stefano Brivio

test/lib: Drop perf_report_append() from perf_report

2022-09-23T22:09:23+00:00

It's not used anymore. While at it, fix the function name in the
comment to perf_report_append_js().

Signed-off-by: Stefano Brivio

test/lib: Wait for DHCPv4 before starting DHCPv6 client in two_guests test

2022-09-23T00:46:24+00:00

I'm not sure why, but dhclient hangs otherwise. This reflects what we
do in the passt_in_ns setup steps.

Eventually, this whole block could go away if we let pasta configure
this network namespace with --config-net.

Signed-off-by: Stefano Brivio

test/lib: Wait for kernel to free up ports used by iperf3 before reusing them

2022-09-22T14:54:09+00:00

If we start another server on the same port right away, we might fail
to bind the port. A small delay appears to be needed -- I'm not
entirely sure why at this point.

Signed-off-by: Stefano Brivio