Re: [PATCH] [gdb/testsuite] Update xfail in gdb.threads/attach-many-short-lived-threads.exp

[Carl Love <cel@linux.ibm.com>]

Tom:

So I have spent some more time playing with this test.  I have played with adjusting the timeout with no clear improvement in the reliability of the test.

I see that once we hit the EPERM failure, the test skips the tests for the rest of that iteration and then tries to attach again to the same testpid on the next iteration of the test loop.  On Power 10, this results in a timeout on the attach and all the rest of the gdb commands timeout for all subsequent test loop iterations.  So depending on which iteration the error occurs on you get a different number of failures from run to run.

So, it seems like we need handle the EPERM error differently from what is currently being done.  I can think of
three possible ways to handle the error, as I put into the latest update of the issue.  If you have any other ideas on how we could handle the EPERM failures please let me know.  My third suggestion does seem to fix the test but I have to say I am not entirely happy with that fix.

https://sourceware.org/bugzilla/show_bug.cgi?id=31312

Please add your thoughts on my solution and any additional solutions to the bugzilla.  Thanks for your help on this issue.

                        Carl