Beginning OpenMP Threads

Beginning OpenMP Threads

[Mohamed Atef]

Hello everyone,
  From OpenMP specs.
"The OpenMP implementation must execute ompd_bp_thread_begin at every
native-thread-begin and initial-thread-begin event. This execution occurs
before the thread starts
the execution of any OpenMP region"

"When terminating an OpenMP thread, the implementation executes
ompd_bp_thread_end."

are these team_start and team_end in team.c file?

Thanks
Mohamed

Re: Beginning OpenMP Threads

[Martin Jambor]

Hi,

it's been a while since I had a serious look into libgomp...

On Fri, Feb 25 2022, Mohamed Atef via Gcc wrote:
> Hello everyone,
>   From OpenMP specs.
> "The OpenMP implementation must execute ompd_bp_thread_begin at every
> native-thread-begin and initial-thread-begin event. This execution occurs
> before the thread starts
> the execution of any OpenMP region"
>
> "When terminating an OpenMP thread, the implementation executes
> ompd_bp_thread_end."
>
> are these team_start and team_end in team.c file?

...but - based on a rather quick look - while I think you correctly
tracked down that gomp_team_start is the place actually creating the
threads, I think that the OMPD implementation wants to execute the
ompd_bp_thread_begin function for each thread and by the native
(pthread) thread.  And, as far as I can tell, that seems to be the
function gomp_thread_start.  At the moment I cannot quite tell if the
end of the function would be a good place for the thread termination
event - or rather if it is sufficient and there may be others, I would
need to dig deeper.  But perhaps this already help?

Martin

Re: Beginning OpenMP Threads

[Mohamed Atef]

Hi,
  Thanks a lot.
The good news is that by the end of this month I think we will finish most
of OMPD.
The remaining parts need OMPT support which is missing in GNU but all the
other functions work perfectly fine.

Finished work,
  Initialization
  Thread handles
  ICVs

remaining work,
  task handles
  parallel region handles

Thanks

Mohamed

On Mon, Mar 7, 2022 at 7:40 PM Martin Jambor <mjambor@suse.cz> wrote:

> Hi,
>
> it's been a while since I had a serious look into libgomp...
>
> On Fri, Feb 25 2022, Mohamed Atef via Gcc wrote:
> > Hello everyone,
> >   From OpenMP specs.
> > "The OpenMP implementation must execute ompd_bp_thread_begin at every
> > native-thread-begin and initial-thread-begin event. This execution occurs
> > before the thread starts
> > the execution of any OpenMP region"
> >
> > "When terminating an OpenMP thread, the implementation executes
> > ompd_bp_thread_end."
> >
> > are these team_start and team_end in team.c file?
>
> ...but - based on a rather quick look - while I think you correctly
> tracked down that gomp_team_start is the place actually creating the
> threads, I think that the OMPD implementation wants to execute the
> ompd_bp_thread_begin function for each thread and by the native
> (pthread) thread.  And, as far as I can tell, that seems to be the
> function gomp_thread_start.  At the moment I cannot quite tell if the
> end of the function would be a good place for the thread termination
> event - or rather if it is sufficient and there may be others, I would
> need to dig deeper.  But perhaps this already help?
>
> Martin
>
>