Re: [PATCH] Fix error when gdb connect to a stub that tracepoint is running[1/2] reset current_trace_status in the begin of remote_start_remote

[Hui Zhu <hui_zhu@mentor.com>]

Hi Pedro,

What about my patch in 
http://sourceware.org/ml/gdb-patches/2012-01/msg01007.html ?
It make tracepoint cannot be install before remote_get_trace_status.
And after remote_get_trace_status, merge_uploaded_tracepoints can handle 
tracepoint.

Best,
Hui

On 02/09/12 02:31, Pedro Alves wrote:
> On 01/31/2012 08:22 AM, Yao Qi wrote:
>> Patch attached is used to illustrate my thought to fix this problem.  I
>> am not confident on it because I don't know it is correct to change the
>> order of function calls in remote_start_remote.  The "non stop" path in
>> remote_start_remote is not affected by this patch.  In the "stop" path,
>> the order of some functions call is changed, but don't know they are
>> equivalent.
>>
>>     Original                            Patched
>>
>>     start_remote                  merge_uploaded_tracepoints
>>     remote_check_symbols          start_remote
>>     merge_uploaded_tracepoints    remote_check_symbols
>
> The tracepoints module depends on remote_check_symbols (qSymbols), in
> order to detect the IPA is loaded, and so that anything related
> to fast tracepoints works.  On the other hand, if there are already
> fast tracepoints on the target, then the qSymbols business must have
> already have been done in the previous time gdb was connected.
>
> I don't think we're okay with this in non-stop mode though.  We should
> relocate our symbols before we try to merge tracepoints.  Yet, we need to
> merge tracepoints before any breakpoint re-set.  Thing is in non-stop mode,
> you find new inferiors and possibly do re-sets early in remote_start_remote
> (find threads ->  remote_notice_new_inferior ->  notice_new_inferior can do a lot
> behind the scenes).
>
> It may be simpler and safer to just have a way for update_global_location_list
> to know that it shouldn't try to install tracepoints yet (cause we're still going
> through startup)?
>