[gomp4] libgomp.c/target-1.c failing in fn2's GOMP_target_update

[Jakub Jelinek]

On Fri, Nov 08, 2013 at 04:29:03PM +0100, Thomas Schwinge wrote:
> 
> On the gomp-4_0-branch, when using the ID 257 device (host fallback but
> with non-shared memory), I see the libgomp.c/target-1.c test fail in
> fn2's GOMP_target_update call:
> 
>     libgomp: Trying to update [0x601a80..0x601a84) object that is not mapped
> 
> Is this a known issue?  (I have not yet started debugging that, and
> figured someone more familiar with the code may perhaps easily be able to
> tell what's going wrong.)

That is expected, device 257 is just a temporary testing hack, which doesn't support
variables with "omp declare target" attribute.
So, you can only use it for testcases that don't have any #pragma omp
declare target variables, or if they do, they only access them in #pragma
omp declare target functions, but never try to use them or anything related
to them in map/to/from clauses.
The plan is that using the two proposed tables (host table of host_addr, size
pairs and corresponding target table of target_addr) during initialization
of offloading for a particular shared library resp. binary libgomp will
register all those ranges in the mapping table.

> That aside, I'm using the following patch to enable the ID 257 device
> without having the LIBGOMP_PLUGIN_PATH environment variable set; OK for
> gomp-4_0-branch?

I guess it is ok, once we have at least one supported offloading target,
hopefully we'll nuke device 257.

> libgomp: Always set up device 257 if no other device has been found.
> 
> 	libgomp/
> 	* target.c (gomp_find_available_plugins): Don't skip device 257
> 	setup.
> 
> diff --git libgomp/target.c libgomp/target.c
> index c0730a7..d84a1fa 100644
> --- libgomp/target.c
> +++ libgomp/target.c
> @@ -651,11 +651,11 @@ gomp_find_available_plugins (void)
>  
>    plugin_path = getenv ("LIBGOMP_PLUGIN_PATH");
>    if (!plugin_path)
> -    return;
> +    goto out;
>  
>    dir = opendir (plugin_path);
>    if (!dir)
> -    return;
> +    goto out;
>  
>    while ((ent = readdir (dir)) != NULL)
>      {
> @@ -675,7 +675,7 @@ gomp_find_available_plugins (void)
>  	{
>  	  num_devices = 0;
>  	  closedir (dir);
> -	  return;
> +	  goto out;
>  	}
>  
>        devices[num_devices] = current_device;
> @@ -686,6 +686,7 @@ gomp_find_available_plugins (void)
>      }
>    closedir (dir);
>  
> + out:
>    /* FIXME: Temporary hack for testing non-shared address spaces on host.
>       We create device 257 just to check memory mapping.  */
>    if (num_devices == 0)
> 
> 
> Grüße,
>  Thomas



	Jakub