racct: Add some tests

[cyril_freebsdfoundation.org]

Summary

This revision adds some tests for racct. They test the upcoming addition of racct to POSIX shared memory as well as the upcoming fixes to pcpu and cputime calculations.

[markj]

Overall this looks good to me. There are some stylistic nits which I pointed out.

What do you think of adding a short test to verify the runtime accounting? It might be easiest to write a short C program which loops for N seconds (with N == 3 or so, we don't want tests that take too long to run) and exits. alarm(3) would be a useful function there.

tests/sys/racct/Makefile

2

This can be removed, it's a holdover from when we used Subversion. It's not useful anymore.

tests/sys/racct/racct_jail.sh

6 ↗

(On Diff #91531)

It's good form to also set descr to a sentence describing what the test is verifying.

97 ↗

(On Diff #91531)

Rather than checking exit statuses manually, you might consider using atf-check(1).

121 ↗

(On Diff #91531)

Since you're defining names for the parameters, it's a bit nicer to make them locally-scoped:

local jailname i size

jailname=$1
...

135 ↗

(On Diff #91531)

A simpler way to write these kinds of loops is

for i in $(seq 1 $max); do
...
done

Then you don't need to initialize $i or increment it.

[cyril_freebsdfoundation.org]

I have added a test for cputime and pcpu which takes 4 seconds to complete. Since it is a loop that executes another process, the calculations involved are inexact (compared to a loop that simply spins) and we cannot expect a precise value for these measurements.

I have also added another interesting test, for maxproc. It is a currently failing test, but I'm not sure why. The test uses a process to create 6 children, but expects to fail on the last one. In my manual testing, I have found that it instead fails on the 5th child even though maxproc is set to 5 (the parent process does not count as one of the processes, since it is executed using jexec). We can change this to atf_expect_fail, if needed.

[cyril_freebsdfoundation.org]

Adds copyright notices.

[cyril_freebsdfoundation.org]

Remove unnecessary quoting and ignore error messages.