Re: [Myrinet] (No Subject)

Salut Julien,

TOUCHE Julien wrote:
> with your help, i solve the problem with gm_dma_alloc(), but there is 
> always a problem of "incompatibles types assignement" with 
> gm_register_memory()

In the code:
 > *buffer = gm_register_memory(port,
 > 		 
	buffer,
 > 		 
	(unsigned int)(size_mem*sizeof(char))
 > 		 
	);		// DMA transfer register

gm_register_memory return a type gm_status_t. The right code should be :

*buffer = gm_malloc(size_mem*sizeof(char));
if (gm_register_memory (port, *buffer, (unsigned int)
       (size_mem * sizeof(char) != GM_SUCCESS)
{
   /* something bad happen */
}


> when i use
  __GM_DMA__ (see end), it compiles but i have the following
> error:
> "gm_open: send dropped as requested by the client"

There is many errors in the code. For example:
* in allocate_gm_buffer, a piece of memory should be allocated before to 
register it.
* in allocate_gm_buffer, in the call to gm_register_memory, "buffer" 
should be "*buffer";
* in unallocate_gm_buffer, all the "buffer" should be "*buffer";
* The value of remote_address is uninitialized.
* Why do you gm_provide_receive_buffer on "remote_address" before to do 
a gm_directed_send to the same (uninitialized) address on the other node 
? gm_directed_send is like a PUT, you only need to register or dma_alloc 
  on the receiver side the memory you want to write to, and the sender 
only call gm_directed_send with the virtual address of the *buffer on 
the receiving side*.
* you didn't understand the notion of Sizes in GM. I don't blame you, 
it's one of the very bad parts of the API, it took me months to (almost) 
understand what it is. It's like a tag with a relationship with the 
length of the message, insane. Anyway, think about it like a tag with a 
value between 8 and 31. The relationship with the length has been 
relaxed a long time ago actually.

> i have also a mpi test which doesn't execute correctly, i don't know 
> why ? i send a message to another nodes, and it returns but not 
> modified ...

I looked at it very quickly and the buffer "message" is size_mem 
characters, but the MPI operations send/recv size_mem integers (MPI_INT).

>   	message = (char *) calloc(size_mem,sizeof(char));
[...]
> 		  MPI_Send(message, size_mem , MPI_INT, next, TAG, MPI_COMM_WORLD );

Patrick

----------------------------------------------------------
|   Patrick Geoffray, Ph.D.      [email protected]
|   Myricom, Inc.                http://www.myri.com
|   Cell:  865-389-8852          685 Emory Valley Rd (B)
|   Phone: 865-425-0978          Oak Ridge, TN 37830
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