stress-ng should better handle unknown options

[Jeff Lane ]

unning stress-ng sync-file stressor for 240 seconds....
stress-ng: unrecognized option '--sync-file'
Try 'stress-ng --help' for more information.
return_code is 1
*****************************************************************
** Error 1 reported on stressor sync-file!)
*****************************************************************

stress-ng returns output like above when a test case doesn't exist. This could happen where that feature works on one arch, but is not supported on another (e.g. x86_64 vs ppc64el)

So disk_stress_ng should do one of the following:

Maintain separate arch specific test lists and become arch aware to dynamically create test lists at runtime.

OR

Intercept these cases, pass a warning message to logs/output, and pass on these tests.

[Colin Ian King (colin-king)]

I will look at adding a warning and a return code 4 (EXIT_NOT_IMPLEMENTED) to cater for this. I may take me a while to implement because it requires a re-working of most of the 160 or so tests.

How about a pr_info message "<stressor-name>: this stressor is not implemented on this system: <arch> <kernel-release>", e.g.

stress-sync-file: this stressor is not implemented on this system: ppc64el 4.8.0-26-generic

[Jeff Lane  (bladernr)]

That would be pretty cool, honestly, Colin, I didn't even think you'd see this. I mistyped the heading apparently, because I was actually referring to the disk_stress_ng wrapper script.

But now that you bring it up, an exit code other than 1 would be awesome and much easier to trap (and certainly less functional overhead on the user end than wrappers that make decisions based on discovered architecture)

[Jeff Lane  (bladernr)]

Also, much easier than my other idea of a regex match to catch expected messages in output.

[Colin Ian King (colin-king)]

Fix(es) commited:

http://kernel.ubuntu.com/git/cking/stress-ng.git/commit/?id=67d872611b860a79b03dca8c7549e5cee7fec4eb
http://kernel.ubuntu.com/git/cking/stress-ng.git/commit/?id=3b8309886899a070c66360a13fe1ee3180477412

I've uploaded this to debian, hopefully will get sync'd into Ubuntu Zesty in a day or so

[Colin Ian King (colin-king)]

stress-ng V0.07.02 now has been released with fixes to address this. Let me know if it needs further work to assist you with this issue.

[Colin Ian King (colin-king)]

Since this is a plainbox / checkbox bug, can this be assigned to an owner of that project as I believe I have fulfilled the requirement for stress-ng on this side of the issue.

[Sylvain Pineau (sylvain-pineau)]

Sure, thanks Colin