Re: [patch] Fix for PR gdb/10757

[Pedro Alves <pedro@codesourcery.com>]

On Tuesday 27 October 2009 00:41:24, Paul Pluzhnikov wrote:
> 
>   static __volatile__ int thread_iteration_in_progress;
>   static __volatile__ int thread_creation_in_progress;
> 
>   __pthread_create_2_1 (...)
>   {
>     while (thread_iteration_in_progress) nanoslep ...;
>     atomic_increment(&thread_creation_in_progress);
>     ... create new thread, put it on thread list ...
>     atomic_decrement(&thread_creation_in_progress);
>     return ...
>   }
> 
> and in
> 
>    td_ta_thr_iter ()
>    {
>      set thread_iteration_in_progress in the inferior to 1
>      while (thread_creation_in_progress in inferior > 0)
>         nanosleep ...
> 
>      iterate over the thread lists ...
> 
>      set thread_iteration_in_progress in inferior to 0
>    }
> 

This does make the race window narrower, but it doesn't
completely kill it, as new threads could have passed the
thread_iteration_in_progress check already as gdb enters the
thread iteration loop.

-- 
Pedro Alves