Re: [PATCH] testsuite: Persistent gdbserver cleanup

[Pedro Alves <palves at redhat dot com>]

On 10/23/2013 11:59 PM, Maciej W. Rozycki wrote:
> Hi,
> 
>  We have a number of tests that run `gdbserver' in the persistent mode, to 
> be able to disconnect and reconnect.  That has a side effect of leaving 
> the `gdbserver' behind upon GDB termination at the conclusion of the 
> respective test cases, because no kill request is sent to `gdbserver' at 
> the end of session and as a result of receiving a KILL signal GDB merely 
> disconnects.
> 
>  This causes problems in some remote test environments, such as QEMU in 
> the system emulation mode, where `gdbserver' is run within Linux run on 
> QEMU and QEMU's TCP port forwarding feature is used to communicate with 
> the `gdbserver'.  In this case a single TCP port is used to talk to 
> `gdbserver' and a subsequent test case faces `gdbserver' still running 
> controlling the program used for the test case that has just concluded.  
> 
>  Killing off that `gdbserver' process, while possible, is complicated and 
> I think test cases should try to leave the state clean if possible, so 
> here's my proposal to make the harness explicitly request `gdbserver' to 
> terminate before killing off GDB where the persistent mode has been 
> requested.  Additionally one test case terminated GDB in a disconnected 
> state, so I made it reconnect before completion.
> 
>  No regressions in mips-linux-gnu testing.  OK to apply?

Seems OK.

Though I think this won't work in extended-remote mode, where
"kill" won't actually bring down gdbserver.  I think we'd need to use
"monitor exit" for that instead.  (I think we'd do that with a new
gdbserver_finish hook in gdbserver-support.exp that instead of
hardcoding that gdbserver-specific command in gdb_finish).  But it's fine
with me if you don't want to fix that.

-- 
Pedro Alves