Arnd Bergmann wrote:

On Sunday 04 February 2007 00:49, Maynard Johnson wrote:
 

quoted

I seem to recall looking at this option a while back, but didn't go that 
route since struct spu_context is opaque to me.  With such a teqnique, I 
could then use a simple 16-element array of  pointers to cached_info 
objects, creating them as needed when spu_context->profile_private is 
NULL.  I suppose the better option for now is to add a 
get_profile_private() function to SPUFs, rather than requiring 
spu_context to be visible.
   

Yes, that sounds good. Note that the file providing the 
spufs_get_profile_private (and respective spufs_set_profile_private)
functions needs to be compiled into the kernel then in case oprofile
gets linked in but spufs is a module.
 

Hmm . . . we already depend on the register/unregister functions in 
sched.c, so my patch changes the oprofile Kconfig to default to 'm' and 
'depends on SPU_FS'.

I think it would also be necessary to have another interface for cleaning
up this data when spufs destroys the context. That could possibly
a variation of the existing notifier call, or a new call, or you
establish the convention that if the private pointer is non-NULL,
spufs will kfree it.
 

Yes, I was thnking along the lines of your last suggestion.  I presume 
OProfile gets notified (object_id == 0) before the context is actually 
destroyed.  At that time, we would NULL-out the reference to the 
cached_info, so then SPUFS would kfree it at destroy time.

-Maynard

Arnd <><